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AN ACCOUNT

OF THE

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPAGTICOIDA

PARTS I & II

MISOPHRIIDjE, LONGIPEDfflXE, CERVINIIDJE, ECTINOSOMID^E

(PART)

WITH 16 ATJTOGKAPHIC PLATES

BERGEN
PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMERMEYER'S FORLAG, CHRISTIANIA
* 1903

INTRODUCTION.

Of all the groups of the Copepoda, that of the Harpacticoida is undoubt-
edly the most extensive, and at the same time the most difficult to examine,
on account of the generally very small size of the forms comprised within it,
some of them being indeed almost undistinguishable to the naked eye. The most
prominent character whereby the present group is distinguished from that of the
Calanoida is, as clearly shown by Dr. Giesbrecht, the very movable articulation of
the last segment of the metasome with the preceding segment, and its firm con-
nection with the 1st segment of the urosome, giving it the appearance of more
properly belonging to that section of the body. Thus far this group perfectly
agrees with that of the Cydopoida, and. indeed Dr. Giesbrecht comprised both in
his division Podoplea. I find it, however, more appropriate to keep these 2 groups
apart, as in other respects they differ from each other rather materially. By
most authors, the group here in question is regarded only as a family, Har-
pacticidce; and the numerous genera comprised within it have of course been ar-
ranged under a series of subfamilies. In accordance with the arrangement adopted
by the present author, as regards the Calanoida, these subfamilies are here re-
corded as true families, and their number has been considerably augmented.
Moreover an attempt has been done to group these families under a few sections,
as will be shown farther on.

The type of the present group is the genus from which its name is
derived, viz., Hqrpactifti* Milne-Edwards; and indeed this genus seems to combine
some of the most characteristic features of the group, and in all probability con-
stitutes a very primitive form. The difference, both as regards the external appear-
ance and the structural details, between this genus and those of the Calanoid and
Cyclopoid groups is very conspicuous ; yet we find many deviations from this
type, tending partly towards that of the Calanoida, partly towards that of the
Cydopoida, and in most cases a very gradual change in one or other direction
may be easily demonstrated.

1 Crustacea.

A.G ;<-i:ards the general shape of the body, in tin' .ureater number of the
form* it is very -lender and more ui- less cylindrical, with m> very pronounced demar-
cation between the anterior and posterior divisions. In some cases, however, tin-
posterior division, including tin- la-t segment of the nietasome. appears abrupth
much narrower than the anterior, which may be more or less expanded. a-> in
the Cyclopoida, tor instance, in the genera J//wy>/wia, /'-< itilnttirlinlitts. lili/n. etc.
In BOme torms both the anterior and posterior divisions appeal' greatly expanded,
whereby the body acipiires a pronouncedly depressed, even leaf-like form, as in
the genera y.ini^. f'i Itiiiiniti. /' i '< > Iliiiiniii. In other cases, quite contrary to this,
the body is found to be highly compressed, for instance in the genus .|////////o///\

The cephalosome is generally coalesced with the 1st segment of the meta-
sorae, though in some lew forms a well-marked demarcation between them ma\
be found to exist. The lateral parts of this section are more or less expanded,
being so deep in some forms, e. g. the genus I.itiii/i/x <lin. that they wholly include
between them tbe oral appendages. It projects in front in a more or less distinct,
generally lamellar rostrum, which in most cases is movably connected with the
cephalic shield. The 3 succeeding segments of the metasome are always well
defined, and are provided with more or less distinct epimeral plates. The last
segment of the metasome, as stated above, has always a very movable articulation
with the preceding segment, whereas it is firmly connected with the 1st segment
of the urosome. Its epimeral plates are generally obsolete, or at any rate much
smaller than on the preceding segments. The urosome is composed of 5 segments,
the first 2 of which, however, in the female are more or less completely coalesced,
though in some forms a distinct suture between them is seen dorsally. In the
male these 2 segments are always distinctly separated, and the 1st of them pro-
jects at the end, on each side of the ventral face, to a small setiferous process.
The caudal rami are in most cases short, and firmly connected with the last
caudal segment. Of the apical setae, as a rule, only the L? middle ones are well
developed, the others lieim: more or less rudimentary. A single eye is generally
present, though in some forms, esp,.ciall\ in those from deep water, no trace of
such an organ is to be found.

The anterior antenna- are. as a rule, of inferior si/e and composed
of a limited number of articulations, ran-l\ (as in the -enus )f^/ihr/n ) ex-
eeding H in all. One of the articulations, -enerally the .",rd or Itli. exhibits
at the end anteriorly a projecting knob, to \\hich a slender sensory appen-
dage is attached, and the succredini: portion of the antenna is generally
abruptly narrowed, forming a well-defined terminal part. In the male both these
antenna- are pn-ln nsile. and often Breath swollen in their outer part. The

posterior antennae are on the whole more strongly built than in the Calanoida,
and are generally tipped with coarse denticulated spines. They always carry a
secondary appendage (outer ramus ) ; but in most cases this appendage is of rather
inferior size as compared with the chief stem (the inner ramus). The mandibles
carry outside a more or less developed palp, and this is also generally the case
with the maxillae. The anterior maxillipeds are short and stout, with several
digitiform processes, the number of which may however be considerably reduced.
The posterior maxillipeds in the majority of forms are pronouncedly prehensile,
terminating in a powerful clawed hand. There are, however, a number of forms
in which these appendages are of a very different structure, and not prehensile
at all. The 1st pair of legs are in some instances of a structure similar to that
of the succeeding pairs; but in the majority of cases they differ rather conspicu-
ously, being more or less transformed into grasping organs. The 3 succeeding
pairs are always natatory and generally have both rami 3-articulate, though the
inner one may sometimes be much reduced in size. The last pair of legs are
very unlike the others, and are never natatory. They are generally lamellar in
structure, biarticulate, and edged with strong setse or spines.

The ova are in most cases carried within a single ovisac attached to the
ventral face of the 1st caudal segment. More rarely 2 ovisacs are present, which
likewise are appended to the ventral face, never, as in the Cyclopoida, laterally
or subdorsally.

With regard to the inner organisation, it may be noted that, unlike what
is the case in the Calanoida, no heart is present (except in the genus Mis&phria),
and that the male genital apparatus is always perfectly symmetrical.

By far the greater majority of forms belonging to the present group are
marine, only a very limited number of genera being represented in fresh water.
Some species seem, however, to prefer brackish water, and so far cannot properly
be said to be either true marine or true fresh-water forms. Contrary to what is
generally the case with the Calanoida, the Harpacticoida are, as a rule, true
bottom forms, to be sought for among algse near the shores, in tidal pools, or in
mud brought up from various depths. But in this respect also there are some
exceptions. Thus the species of the genera Setella, Euterpe, Clytemnestra, Mi-
1'iK-ia, lead a true pelagic life. Some few forms are known to be commensal
with other Crustacea (Sunaristes), or even with Vertebrates (Balcmiopliilus) ; but
no true parasites are as yet known among the Harpacticoida.

The several families comprised within the present group may be arranged
under 2 chief sections. In the one, Achirota, the posterior maxillipeds are of
weak consistency and not prehensile; in the 2nd, Chirognatha, these appendages

an- pronouncedly prehensile, terminating in a more IT less powerful, clawed hand.
Tlic latter section may au r ain be conveniently divided into ~2 subsections, according
to the structure of the 1st pair of le.ns. In the one subsection, Chirognatha

!>/, ,,/,,, <l,i. these legs are of a structure similar to that of the succeeding pairs
and. like them, natatory: in the other sub-section. (.'liii-"<intitli<i 'I'li-h/lnjuJii. they
an- rather unlike the succeeding pairs, and more or less distinctly transformed
into grasping organs.

Section I. Aehirota.

/.'. nun-Is*. This section is far less extensive than the next. It com-
prises. however, as yet, 4 different families, each of which, except the 1st, contains
se\eral well-defined genera. The chief characters common to all of them is the
m>n-prehensile structure of both the posterior maxillipeds and the 1st pair of
legs. In the latter character they agree with those belonging to the 1st sub-
division of the next section.

The greater number of species are true deep-water forms, and it is very
pr<>hable therefore, that on a future closer examination of deep-water deposits,
several additional forms will be detected, requiring perhaps the establishment of
both new genera and new families.

Fam. 1. Misophriidae.

Characters. -Body (///In/nut! in shape, the posterior division (including
the last segment of metasome) being abruptly much narrower than the anterior.
Anterior antennae unusually prolonged, and consisting of numerous articulations;
both antenme in male, as usual, prehensile. Posterior antenna' and oral parts
of a structure rather similar to that in the ('nl<inniil<i. Natatory legs more
i-i/rlnfioiil in shape, and rather powerful, with both mini lri:irticulate. Last pair
of h-^s 3-articulate, and of same appearance in both sexes, < hisae single, ventral.
A heart present, as in the ('iiluiinnln. Male genital apparatus symmetrical,
like that in the other //iirjitx-tirtiitla.

//<//"///>. -This family, established by Prof. Brady, has generally been
placi-d between the Ciiltiiiniiln and Ci/cln/,i,iiln. hein.i,' regarded by some authors
as more nearly related to the former group, by others as nearer to the latter.
In my opinion, it ought more properly to be included in the Ilnr[i/iclifnnl group,

though in some respects it certainly exhibits an apparent resemblance both to the
Calanoida and to the Cyclopoida. That at any rate the typical genus Misophria
cannot be referred to the former group, has been clearly shown by Dr. Giesbrecht;
and he also finds it impossible to class it among the Cydopoida, because the
posterior antennae have a well-developed outer ramus, wholly absent in all known
forms of that group. So far I fully agree with that author; but, on the other
hand, I cannot concur in his opinion that the difficulties in referring this form
to the Harpacticoida are equally great. True, the anterior antennae look rather
different from their comparatively greater length and more numerous articu-
lations; but this character is evidently of far less importance than those referred
to as distinguishing the genus from the Calanoida and Cyclopoida. There is an-
other character, to which Dr. Giesbrecht has called attention, and which, indeed,
seems to be of much greater importance, viz., the presence in Misophria of a
distinct, though rather small and imperfectly developed heart. Such an organ,
as is well known, is wholly absent in both the Cyclopoida and the Harpacticoida,
whereas in the Calanoida it is always present. As, however, several other impor-
tant features (for instance, the mode of articulation of the last segment of the
metasome, and the symmetrical structure of the male genital apparatus) make it
quite unreasonable to place the genus in that group, we must set aside this
peculiarity, and otherwise decide to which of the 2 groups, Cyclopolda, or Har-
pacticoida, it should rightly be referred. For my own part, I consider a character,
not found out by Dr. Giesbrecht, to be quite conclusive, viz. the presence in
Misophria of only a single ventral ovisac.

In addition to the typical genus, Prof. Brady refers 2 other genera to
the family Misophriidce, viz., Pseudocyclops and Cervinia, and to the same family
Mr. Th. Scott subsequently referred another genus, Paramisophria. All these 3
genera must, however, be discarded from the present family, 2 of them, Pseudo-
cyclops and Paramisophria being, as shown by Dr. Giesbrecht, true Calanoids,
whereas the 3rd belongs to a very different family of the Harpadicoida, viz.,
Cerviniidce, to be treated of below. Of course the present family as yet com-
prises only a single genus.

Gen. 1. MiSOphria, Boeck, 1864.

Generic Characters. Body comparatively robust, sub-depressed, with the
anterior division considerably expanded. Cephalosome wholly confluent with the

1-t segment <>i' the inetasome. and produced in iVont to an immobile rostrum.
List segment uf nieta-"iiie abruptly much narrower than tin 1 preceding ones, and
without any distinct epimeral plates. I'rosome rather narrow, and Bubcylindric
in form: u'enital se^im-nt in female with :i well-defined trans\ ersal suture dorsally
in tin- niiddl' ' nidal rami short, with the innermost apical seta well developed,
though ci,iisider:ibl\ shorter than the '2 middle ones. K\ e wholly absent. Anterior
antenna' >leinlei-. atteiniateil. many-jointed, those in male distinctly geniculate.
witli all 3 sections well defined. Posterior antenna' with the inner ramus dis-
tinctly :;-articnlale. and carrying on the tip slender curved set, outer ramus
well developed, tln>ui.di Mualler than the inner, and 6-articulate. Mandibles with
the ma>ticatoi-y jiart lamellai'l\ expanded, and divided into several denticulated
teeth, palp larp 1 , biramoiis. with both rami hiarticulate and carrying slender setse.
MaxilL-e very fully developed, and exhibiting all the parts found in those of the
('iiliiii,,nl<i. inner ramus of palp greatly elongated, Inarticulate. Anterior maxil-
lipeds robust, \\ith the normal number of digitifonn lobes, the outermost bein.n
produced to a strong claw. Posterior maxillipeiK more slender, and resembling
in structure those in the ('nl<in<>i<l<i. terminal part .^-articulate. Natatory le-s
with comparatively broad, flattened rami. those of 1st pair of about equal si/e.
those of the .'j succeeding pairs somewhat unequal, the outer one being the larger.
La-t pair of legs consisting each of 3 flattened joints carrying scattered setae.

Remarlcs.This genus, established by Hoeck. was placed by that author,
with Mime hesitation, among the ( '//i-ln/nnilii. and indeed its external appearance
is pnun.uncedly cyclopoid. There is also in this respect a perplexing similarity
between this genus and some calanoid genera, vi/., Pseudocydops and /'<tr<tini-
tirin. On a closer comjiariMin. it may. hovvexer, at once be distinguished from
the-e -_'eiiera hy the vei-v different mode of articulation of fhelat segment of the
metasome, and Irom the ('//rlii/inn/u by the single ventral ovisac. The genus as
vt compi'iscs only a MiiL r le s|iecjes. tu lie described below.

1. Misophria pallida, l>oeck.

in. i \ ID.

\l- *'/,/,, in jin/Hilii, l'.i...,-U. ii, over '! \ed Gorges K\SI.T rt-ttM-iP' (.|,f|,.>c|.r. Clir. Viil.

I. 1st; i. ,,. 248.

Si/fi-i/ir ( 'htifiicl/i's. l-"i null, . . \ntei-jor division of body rounded oval in
fun, i. with the dor>al lac,, evenly vaulted. Cepbalosome (including the 1st segment
of metasome) occupvin^ about -' of that division, rustral pi'ojection very sfi-on^.
acute at the lip, and pointing straight duwnvvards. i'cnultimate sequent of mela-

some deeply emarginatecl behind, and almost wholly encompassing laterally the
small last segment. Urosome not attaining half the length of the anterior division,
genital segment slightly dilated in its anterior part, and exceeding in length the
remaining segments combined. Caudal rami broader than they are long, and
transversely truncated at the tip, apical setse rather elongated and densely plu-
rnous, the innermost but one fully half as long as the whole body. Anterior an-
tennse about the length of the cephalic segment, and consisting of 16 articulations,
the 3 proximal of which are considerably dilated and densely clothed with partly
ciliated setse. Last pair of legs with the 1st joint conically produced at the end
inside, and carrying on both edges a ciliated seta, that of the inner corner rather
elongated and deflexed; 2nd joint somewhat smaller, and obliquely produced out-
side, with a long seta at the outer corner; last joint oval in form and carrying
on the tip a lanceolate, denticulated spine and a slender seta, outer corner pro-
duced to a small dentiform projection. Ovisac small, rounded, and containing a
very limited number of large globular ova.

Male considerably smaller than female, with the anterior division of the
body less expanded. Genital segment considerably dilated, and generally contain-
ing on each side a large, oval spermatophore. Anterior antennse composed of
only 13 articulations, basal section considerably dilated and 5-articulate. with
several well-developed sensory appendages in front; middle section very sharply
defined from the basal one, narrow fusiform, and consisting of 6 articulations;
terminal section biarticulate. Last pair of legs scarcely different from those in
female.

Colour whitish, with a pale reddish tinge.

Length of female 0.70 mm., of male 0.55 mm.

Remarks. This peculiar Copepod may be easily recognized from any of
the other Harpacticoida, its external appearance deviating, indeed, considerably
from the ordinary type, and more resembling that in forms belonging to quite
different divisions of the Copepoda. It is unquestionably the most anomalous
form of the whole group.

Occurrence and Habits.- I have found this interesting form occasionally
in several places off the west coast of Norway, in depths varying from 20 to 50
fathoms, sandy bottom. Last summer, a single female specimen was captured in
the Trondhjem Fjord, near Agdenaes, in about 50 fathoms. The solitary specimen
examined by Boeck, was taken at Skudesnses, west coast of Norway.

The animal moves in a manner very similar to that observed in some
of the deep-sea Calanoids, for instance Stephos and Pseudocydops, now proceeding
quite slowly in a somewhat rotatory manner produced by rapid vibrations of the

8

posterior antenna- and oral parts. now with quick leaps effected by powerful
strokes of the natatory legs and the urosome. It keeps constantly close to the
bottom.

/' -triluit'tun. English and Scottish coasts (Brady. Scott), Gulf of Naples
Bsbrecht).

Fam. 2. Longipediidae.

('lt<i>-iirt< r*. Body of normal appearance, more or less cylindrical in form.
with no sharp demarcation between the anterior and posterior divisions. (Vpha-
losoine in some cases distinctly detined t'rom tin- 1 st pedigerous segment ; rostrum
lamellar and movably articulated to the cephalic shield. Eye well developed.
Anterior antennae short and stout, consisting of a \ery limited number of articu-
lations densely clothed with partly spinil'orni setse. Posterior antennae with the outer
r.-imus very fully developed, cylindrical, 6- or 7-articulate. Mandibles and maxilke
with well-de\ eloped and abundantly setiferous palj>s. Anterior maxillipeds calaiioid
in striieture ; posterior ones very delicate, lamellar, and fringed with densely plumoiis
set;e. Natatory legs with both rami ,'5-articulate and rather narrow, being armed
outside with strong spines, inside and at the tip with long, partly spinifonn seta-
1st pair not differing greatly from the others. Last pair of legs with the inner
expansion of the proximal joint very small, distal joint well-developed or rudi-
mentary, (hisac single or double.

///>. -In this family 1 propose to comprise the 3 genera Longipedia

ll.-xsr and ( 'mint'llti Scott, which are undoubtedly closely allied,
and together form a natural group of the Arhn-nt/i. It does not answer to the
subfamily L<.\K\I\>< iliiinf of Brady, to which a much wider raii^e is given, also com-
pri-ing. as it does, the genera Zosirne, l-'rli nn*<n and I !nnl//<i. which in my
opinion oiiLdit to be referred to ither families. The most characteristic features
of the present family are the unusually full development of the outer ramus of the
posterior antennae, the likewise largely-developed palps on the mandibles and
maxilla*, and. finally, the peculiar, delicate structure of the posterior maxil-
lipeds. In all these characters there is a great similarity between the 'A above-
named genera, whereas in other resprctx well-marked differences between them

are found to exist.

Gen 2. Longlpedia, Clnns. 1863.

dutr/tclcr*. Body more or less slender, with the anterior divi-
sion conspicuously compressed. Cephalic segment comparatively large and confluent
with the 1st segment of metasome, its lateral parts very deep, forming broad
vertical lamellae, finely ciliated below, and wholly including between them the oral
parts; rostrum well developed, narrow linguiform. Epimeral plates of the 3 suc-
ceeding segments large, vertical, angularly produced behind, and including between
them the bases of the natatory legs. Last segment of metasome not much nar-
rower than the preceding one, but without distinct epimeral plates. Urosome
gradually attenuated behind, genital segment in female with a very distinct trans-
versal suture in the middle dorsally, and exhibiting at the end of the suture, on
each side, a strong recurved dentiform projection; last 2 caudal segments com-
paratively short. Anal opercle produced at the tip to a spiniform process and
generally having a number of smaller denticles on each side. Caudal rami short,
with the apical setse more or less spreading. Anterior antennae rather robust and
much curved, consisting of 5 imperfectly-defined articulations thickly beset with
strong setae, some of which are plumose, others spiniform and strongly pectinate;
those in male terminating in a clawed hand. Posterior antennae with the outer
ramus fully as long as the inner and very flexible, 6-articulate. First pair
of natatory legs considerably smaller than the succeeding ones, with the spine
outside the 2nd joint of the outer ramus remarkably slender and upturned;
2nd pair with the inner ramus greatly elongated, baculiform, the last joint being
much produced and armed with 3 thick apical spines and 3 marginal ones. Last
pair of legs with the distal joint well developed, lamellar, proximal joint carrying
outside a long digitiform process, tipped by a delicate seta, its inner expansion
very narrow and terminating in a slender curved seta. A single ovisac present
in female.

Remarks. This genus, established by Glaus, is easily distinguished from
any of the other Harpacticoida by the peculiar transformation of the inner ramus
of the 2nd pair of legs to a kind of leaping-pole. a character, indeed, which has
given rise to the generic name proposed by Glaus. It moreover differs materi-
ally from the 2 other genera included in the present family in the presence of
only a single ovisac. Oft the Norwegian coast occur 4 different, though very
nearly allied species, to be described below.

2 Crustacea.

10

2. Longipedia eoronata, t'laus.

(I'l. Ill ,t IV).
Lonyipedia coronntu. Chins. Die freilebenden Copepoden, p. 111. I'l. XIV. ti-s 14 24.

s t ,,-fi/if chill-in-!- I-', mull. Body moderately slender, with the anterior
division, seen dorsally, of nearly uniform width throughout, the posterior one
gradually attenuated. Caudal segments \ v ith the posterior edge perfectly smooth.
without the slightest trace of denticles. Anal operde with ~2 sub-qual denticles
on each side, terminal spine rather elongate. Caudal rami a little longer than
they are broad, and somewhat divergent, apical seta 1 apparently (piite smooth and
considerably spreading, the innermost but one slightly exceeding half the length
of the body. Inner ramus of 2nd pair of legs with the terminal joint almost 3
times as long as the first 2 combined, proximal spine of inner edge placed in
front of that of the outer, the latter occurring at about the middle of the joint.
Last pair of legs with the distal joint oblong quadrangular in form, being scarcely
at all expanded distally. inner expansion of proximal joint with a slender denti-
culated spinule inside the base of the terminal seta.

M<il<- not differing much in external appearance from female, but of con-
siderably smaller size, and easily recognizable by the strongly-hooked anterior
antennae and the distinctly 5-articulate urosome. Genital segment exhibiting at
the end on each side a small 3-setose lappet. Last pair of legs slightly (littering
from those in female.

Colour yellowish gray, with a slight greenish tinge, caudal seta? dark brown.

Length of adult female 1.30 mm., of male 1.08 mm.

/.'< /m//7,>. It seems to me beyond doubt that the above-described form
is that originally examined by Claus. and named as above. On the other hand.
scarcely any of the forms recorded by other authors under that name are
identical with Claus's species, but belong to one or other of the 2 nearly-
allied species described below as L. Smlfi and /,. ,,i/nnr. The present species
may be easily distinguished from these ~2 forms by the total absence of any
denticles on the posterior edge of the caudal segments. In the structure of the
inner ramus of the 2nd pair of legs, it agrees with L. ni'mm-; but the last pair
of legs are rather unlike in the 2 forms, as also tin- si/e of the animal.

Occurrence "ml //aliil*. This form is very common in the upper part of
the Christiania Fjord in depths varying from (i to .'{<> fathoms. miidd\ bottom.
I have also taken it abundantly in the Trondhjem Fjord, and more rarely off the
west coast of Norway. It may be easily obtained by placing the muddy deposits
taken up by the aid of the dredge in a shallow vessel with a small amount of

11

water. The specimens will then at once make their appearance, owing to a pecu-
liarity which they have in common with some other Copepoda, namely, that on
touching the surface, they remain floating upon it. The swimming movements of
the animal are rather rapid, and constitute an even progress through the water.
When keeping to the bottom, it may, however, propel itself in a more abrupt,
jerky manner, by employing the long inner rarni of the 2nd pair of legs like a
pair of leaping-poles.

Distribution. Heligoland, Gulf of Naples (Glaus).

3. Longipedia Seotti, G. 0. Sars, n. sp.

(PI. V, fig. 1).
Syn: Longipedia coronata, Brady, Scott (not Glaus).

Specific, Characters. Female. Very like the preceding species, but ot
somewhat larger size, and perhaps more robust form of body. Posterior edge of
caudal segments fringed throughout with delicate denticles. Anal opercle with
one large and 4 smaller denticles on each side, terminal spine very strong.
Caudal rami about as in L. coronata, the apical setae being very strong and dark-
coloured, though perhaps somewhat shorter than in that species. Inner ramus of
2nd pair of legs with the inner proximal spine of the terminal joint placed behind
the spine of the outer edge, the latter occurring in front of the middle; distal
inner spine generally turned outwards. Last pair of legs with the distal joint
sub-spatulate in form, gradually widening towards the tip, inner expansion of
proximal joint with a very small hair-like spinule inside the base of the ter-
minal seta.

Colour yellowish gray.

Length of adult female reaching 1 .50 mm.

Remarks. This is the form recorded by Brady l ) and Scott as L. coro-
nata Glaus. In one of his numerous papers, Th. Scott has called attention to a
character in which the present form differs conspicuously from another smaller
form, at first only regarded by him as a variety (var. minor) of Claus's species.
This character consists in the different position of the inner proximal spine on
the terminal joint of the inner ramus of the 2nd pair of legs. The author seems,
however, to have been unaware of the fact that in Claus's species this spine has

*) As first pointed out, however, by Th. Scott, Brady has under this name confounded
2 very different Copepods, not even belonging to the same genus, only that regarded by him
as the male being referable to the present species.

12

a \rr\ different position 1'roin that in the present form. Another character by
\vhich the present species may In- easily distinguished from /,. coronata Clans. is
the dense fringe of delicate denticle-, with which the po-terior edges of the caudal
. mi nt are ornamented. .Moreo\er the last pair of legs exhibit some well-marked
differences.

Occurrence. I ha\e found this form oec;i-ioiiall\ at . \ale-nnd. we-t Cl
of Norway, aa al-o in the Trondhjem Kjord just lieiieath steep cliffs, in depths
ranging from 6 to 10 fathoms. In habits it exactly agrees with the preced-
ing species.

English and Scottish coasts (Brady, Scott).

4 Longipedia minor, Scott.

(1M. V. &g. 2).

C0ronafa t var. //C/M/-, Th. Scott, AiUilions t.< tin- F,-mii:i .'I' tlit- Kit-Ill <it' Forth, llth
Report of ili.- Fish. TV Ho..r.l I'm- Scot laud, p. I'oo. pi. H. ii-, s . 11 L'O.

Syn: l^nii/ijii-iliii cm-omita, Boeck, Giesln-i-rlit (IM.I Olau

S/,,ri/ir Clittnirln-x. Fi'nmli'. Hody of the usual form, the anterior divi-
sion being considerably compressed, the posterior slightly attenuated. Posterior
edges of last segment of metasome and those of urosome fringed throughout with
delicate denticles. Anal opercle about as in L. S<-<>l/i. Caudal rami short,
-i-ari-ely longer than they are broad, apical setae strong and very much elongated.
the innermost but one almost attaining the length of the whole body. Inner
rannis of j?nd pair of legs much elongated, inner proximal spine of terminal joint
placed in front of that of the outer edge, the latter occurring behind the middle-
La>t pair of legs with the distal joint much narrower and more elongated than
in any of the other speck's, inner expansion of proximal joint with a slender
Miiooth spinule inside the base of the terminal seia.

Coin in- light yellow, mottled with brown.

Length of adult female -c.-ircely exceeding n.sn mm.

/''///"/7rx. Tin- form was at lir-t regarded by Th. Scott as merely a
variety of /,. i-orniinln Clans; but Mihseipient ly it has been recorded by that
author aa a distinct species under the above name. It is unquestionably identical
with the form described in detail by Dr. < iiesbredit as /.. rnrnnntii Clans: and
the form oli-e|-\ed by Uocck also Seems to belong to the same species, to judge
from the drawing he has left behind. Indeed, the present form is closely allied to
-pecies, though at once distinguishable from it b\ the finely denticulated

13

posterior edges of the caudal segments, and the slender form of the distal joint
of the last pair of legs. It is moreover of much inferior "_size.

Occurrence. This form is found rather abundantly along the whole south
and west coast of Norway, from the Christiania Fjord at least as far as the
Trondhjem Fjord. It generally occurs in a few fathoms' depth among algse, and
thus seems to be a more sub-littoral form than the other species of the genus.

Distribution. Kieler Fohrde (Giesbrecht), Scottish coast (Scott), ? coast
of France (Canu).

5. Longipedia rosea, G. 0. Sars, n. sp.

(PI. V, fig-t3).

Specific Characters. Female. Body less compressed than in the other
species and more abruptly attenuated behind ; integuments unusually thin and
pellucid. Rostral plate comparatively broader and more obtuse at the tip. Ge-
nital segment with the lateral denticles rather small; posterior edge of this and
the succeeding segments with only very slight traces of spinules. Anal opercle
with 3 very small denticles on each side near the base, terminal spine compara-
tively shorter than in the other species. Caudal rami short and thick, rounded at
the tip, each with an oblique series of small denticles dorsally; apical setae of
moderate length, and very conspicuously ciliated, especially the 2 middle ones.
Inner ramus of 2nd pair of legs comparatively shorter than in the other species,
inner proximal spine of last joint at about the same level as the outer spine.
Last pair of legs with the distal joint of about the same appearance as in
L. coronatd, proximal joint with the outer digitiform process comparatively short
and thick, inner expansion with a very small spinule inside the base of the ter-
minal seta.

Body semipellucid, of a whitish colour, and variegated with irregular
patches of a bright rosy hue.

Length of adult female 1.20 mm.

Remarks. In the living state, this form is at once recognized from any
of the other species by its peculiar and beautiful colouring; but, as usual, this
character is lost in preserved specimens, which very soon assume a uniformly
whitish colour. On a closer examination, however, the present species may be
easily distinguished by the more slender form of the body, and especially by the
very distinct ciliation of the caudal setee, which, moreover, are not dark-coloured
as in the other species.

14

trrence. Only a very limited number of specimens of this remarkable

form have hitherto come under my notice. They were taken at different times,
ae off the west coast of Norway (Aalesimd). some in the Trondhjem Fjord,
from rather considerable depths, down to Ion fathoms. Si. me apparently imma-
ture specimens were also picked out of a plankton-sample taken from deep
water, a fact that seems to prove that this form is not so absolutely confined to
the bottom, as is the case with the other species of this genus.

Gen. H. SunariSteS, Hesse, L867.

Syn: Luiiifi/x'iliiin. \V.

Generic ('Itm-m-li >*. Body very slender in form, with the anterior divi-
sion scarcely at all compressed, posterior cylindrical in shape. Cephalosome con-

fluent with the 1st pedigerous segment, lateral parts not completely obtecting the

"ial parts at the sides. Epimeral plates of the succeeding segments small, rounded.
(ienital segment in female without any trace of a transversal subdivision, and
without lateral denticles. Anal opercle smooth. Caudal rami somewhat produced
and slightly divergent, apical setae about as in Longipedia. Anterior antenna'
less robust and less arcuate than in that genus, (i-articiilate. and clothed with
MTV Blender, partly ciliated setae; those in male terminating in a very strong
clawed hand. Posterior antennae and oral pails very similar in structure to those
in /jiiiii/ijH'ilni. Natatory legs, however, somewhat dilVerent. 1st pair of nearly
the same size and structure as the rind, inner ramus of the latter quite normal in
female, slightly transformed in male, the 2 posterior pairs of somewhat simpler
structure than the 2 anterior, and provided with unusually long and slender set;e.
Last pair of b-^s in both sexes quite rudimentary. O\isac iloiible.

/,'' iii'/i/,-. -This genus was established in the year |M17 by the French
naturalist, llessr. to include a peculiar Copcpod found by him as a commensal in
the same shell \\ifh a kind of hermit crab. The genus l.uni/i/nili mi of \V. Midler
is iini|iiestiM|i;il.l\ identical \\ith that of Hesse. As indicated by the name pro-
posed by the former author, this genus is. indeed, nearly allied to Lmnji imini,
exhibiting, as it does, a \.-r\ similar structure of both the antenna- and the oral
parts. In other respects, lm\\e\rr. it differs rather materially, as for instance in
the altogether m.rmal appearance of the inner ramus of the 2nd pair of legs, the
rudimentary condition of the last pan of legs, and the presence in the female of

15

2 ovisacs. Moreover the genital segment in the female does not exhibit any trace
of a subdivision, no transversal suture existing dorsally. The genus as yet only
comprises a single species, to be described below 1 ).

6. Sunaristes paguri, Hesse,

(PI. VI & VII).

Sunaristes paguri, Hesse, Ann. d. Sc. Nat., Ser. V, Vol. VII, p. 205.
Syn: Lonyipedina paguri, W. Miiller.

Specific Characters. Female. Body extremely slender and elongated,
with very thin and flexible integuments. Anterior division slightly widening in
front, cephalic segment rather large, exceeding in length the 3 succeeding segments
combined, rostral plate broad and obtusely truncated at the tip. Last segment of
metasome of about the same width as the preceding one. Urosoine occupying more
than half the length of the whole body, genital segment very large, about equal-
ling in length the 2 succeeding segments combined, and scarcely at all dilated in
front; genital region with 2 unequal setiform appendages on each side. Last
segment much shorter than the preceding ones. Caudal rami about twice the
length of that segment, rather narrow and somewhat attenuated distally, apical
seta? slender and indistinctly ciliated, one of them attached to the outer edge at
some distance from the tip. Anterior antennae of moderate length and somewhat
attenuated, with the apical filaments very slender. Posterior antennse with the
outer ramus somewhat shorter than the inner. The 2 anterior pairs of natatory
legs with both rami of about equal size, the 2 posterior pairs with the inner
ramus shorter than the outer, and carrying on the tip 2 setae and a short spine.
Legs of last pair consisting each of only a very small lamella edged with 4 setae,
the outermost one very slender. Ovisacs (according to Hesse) narrow fusiform
and greatly diverging.

Body semipellucid, of a whitish colour with a yellowish tinge.

Length of adult female reaching 3 mm.

Remarks. As above stated, this form was first described by Hesse under
the above name. Subsequently the same form was observed by W. Miiller, who,
being unaware of the earlier description of Hesse, regarded it as new, and re-
corded it under the name of Longipedina paguri. It is an easily recognizable
form, and perhaps the largest of all known Harpacticoida.

Occurrence. Only a solitary female specimen of this interesting form has
hitherto come under my notice. It was taken up in the dredge, together with

J ) In a just received paper Mr. A. Scott describes 3 additional species from the In-
dian Ocean.

16

some gravelly sand, at Hvalor, outside the Ghristiania Fjord, from a few fathoms'
depth. According to the statements of both M. Eesse and \\". Midler, this form
i- i. r fii< -rally found in shells occupied by the common lu'rinit-crah. /'///"/</////'.
l I'liltm-iln*. I have myself. ho\\e\er. failed to detect any specimens under such
circumstances, nor has this been done hy Th. Scott.

Distribution. French roast (Hesse), Scottish coast i Scott i.

Gen. I. Canuella, Scott, 1893.

i,,, i, nr Chiii'iictt r^. Body nearly cylindrical in form, with very thin and
flexible internments. Ophalosome distinctly defined from the 1st segment of the

metalline, its lateral parts not very deep, rostrum well developed, narrow lingui-
lorm. Kpimcral plates .f the pcdir'erous segments small, rounded. Genital seg-
ment in female exhibiting in the middle dorsaUy a well-marked transversal suture,
lateral denticles wanting: that in male conspicuously dilated, and produced at the
ei:d he]o\\ to -2 acute projections comprising between them a somewhat hollowed
area. Anal opercle simple, rounded. Caudal rami more or less eliminated and
rivatly diverrent. apical setae of moderate length. outer edge with a small seta
about in the middle. Anterior antenna- resembling in structure those in Smui-
though somewhat more robust; those in male le>s dilated at the end.
antenna' with the outer '2 joints of the inner ramus imperfectly
defined, outer ramus very powerful. 7-articulate. '. )ral parts on the whole built
upon the same type as in the 2 preceding genera. Natatory legs rather strongly
built, with the outer corner of the joints more or less produced: inner ramus of
Jud pair of normal appearance in both sexes. Last pair ol le-js. as in Xttmiri*tr*.
rudimentary. Ovisac double.

irl,-*. As observed by Th. Scott, this ^enus is closely related to
though exhibiting si ..... dillei-ences. which make it advisable to keep
it apart. ( )ne of these differences, not referred to by that author, though indi-
cated in the figure of the animal riven, consi-ts in the complete separation of the
1-t pediirerous seLiment from the cephalosome. a character \n-y rarely found in
the rruup in question. Amour oflu-r differences ma\ be named the distinct
transversal suture occurrinr in the middle of the dorsal face of' the genital ser-
ment in the female, and the somevv hat different sf ructure of the posterior antenna'.
natatory legs and caudal rami. T\\<> m-arly-aliieii species of this genus occur olV
the Norwegian coast.

17

7. Canuella perplexa, Scott.

(PI. VIII & IX).

Canuella pcr/i/f.i'd, Th. Scott, Notes on Copepocla from the Firth of Forth. Ann. of Scottish

Nat. Hist, 1893, p. 92, PI. II, figs. 13.

Syn : Lonyipedia coronata $ Brady (not Claus).

Specific Characters. Female. Body of almost uniform width throughout,
or very slightly attenuated behind, with rather deep and conspicuous instrictions
between the segments. Cephalic segment comparatively small, somewhat vaulted
above, and with the lateral parts but slightly expanded; rostral plate narrowly
rounded at the tip. 1st segment of metasome well defined, though much shorter
than the others; last segment scarcely narrower than the preceding one. Urosome
much shorter than the anterior division of the body, genital segment but slightly
dilated in its anterior part; the 3 posterior segments gradually diminishing in size.
Caudal rami scarcely twice as long as the last segment, greatly divergent, and
gradually tapering distally; apical setae minutely ciliated, the middle one about
twice as long as the outer, and equalling in length the urosome. Anterior an-
tennae rather robust, and consisting of 5 articulations, some of the setae very
strong and coarsely pectinate. Posterior antennas with the outer ramus fully as
long as the inner, some of the setse very strong, almost spiniform. 1st pair of
natatory legs considerably shorter than the succeeding ones, spines of outer ramus
rather elongated; 2nd pair with the first 2 joints of the inner ramus considerably
produced at the inner corner. Last pair of legs extremely minute, each forming
a thin plate edged with 4 setse, the innermost but one the longest and distinctly
plumous. Ovisacs large, rounded oval in form.

Body semipellucid, of whitish colour, with a faint yellowish tinge.

Length of adult female 1.30 mm., of male 1.25 mm.

Ih'inarl's. Mr. Th. Scott first called attention to the fact that Prof.
Brady, in his Monograph of the British Copepoda, has, under the name of Longi-
pediu t-oronata Glaus, confounded 2 entirely different Copepoda, the one, regarded
by him as the male sex, being in reality a female Longipedia (= L. Seotti G. 0.
Sars), whereas that recorded as the female of Longipedia coronata is the form here
under discussion. This form was then described by Th. Scott as the type of a new
genus under the above name, and its differences from Longipedia were pointed out.
The most conspicuous of these differences is unquestionably the presence of 2
diverging ovisacs. a feature, indeed, very seldom met with in the Harpaeticoid
group; and it is apparently this anomalous character which has given rise to the
specific name perplexa proposed by that author.

3 Crustacea.

Occurrence. The only place on tin- Norwegian coast where I have met
with this form, is at Fredriksvarn. outside the < 'bristiani:i Fjord. It there occurred
not unfrequeiitlv in a few fathoms d.-ptlu on a sandy bottom partly overgrown

b\ algae.

/ > ^i-ilnitinii. -Enirlisli coaM (Brady). Scottish coast (Scott).

8. Canuella furcigera, G. <>. Sars, n.

(PI. X).

Specific Characters. />/>/"/>. Very like the preceding species, hut with
less deep instrirtions between the segments and with the urosome more abruptly,
attenuated. Genital segment with 2 small juxtaposed lanceolate lappets below.
Caudal rami much larger than in ( '. //*//</. ni. equalling in length the 3 posterior
<\iudal segments combined, and generally greatly divergent, each with a well-
marked carina along the dorsal face, middle apical seta more than twice as long
as the outer one, both very indistinctly ciliated. Structure of the several append-
ages almost exactly as in C. perplexa.

Male resembling that of the typical species, though having the genital
segment comparatively more expanded, and the caudal rami much larger.

Colour yellowish gray, with a few interrupted transversal bands of a deep
ochraceous hue.

Length of female 1.40 mm., of male 1.25 mm.

Ii'i ///'///>. Though very closely allied to the typical species, this form
may at once be recognized by the much fuller development of the caudal rami,
which to some extent seem to be mobile, as in some specimens they are found
to be greatly divergent, in others pointing more backwards. Moreover the in-
strictions between the segments are less conspicuous than in ('. //r///A./y/, and the
urosome, at any rate in the male, is more abruptly attenuated.

()<<-, i rr< an'. I have not infrequently found this form in the upper part
of the Christiania Fjord, nut far from the town, in depths ranging from '2 to 7
fathoms, muddy bottom.

19

Fam. 3. Cerviniidae.

Characters. Body more or less slender, with the anterior and posterior
divisions generally well marked off from each other. Cephalosome in some cases
distinctly defined from the 1st segment of the metasome, rostral plate quite im-
mobile, forming the immediate continuation of the cephalic shield. Caudal rami,
as a rule, much elongated, though scarcely divergent. Eye wholly absent. An-
terior antennae comparatively short and robust, 6 7-articulate, and more or less
densely clothed with partly ciliated setae. Posterior antennse with the outer 2
joints of the inner ramus confluent, outer ramus less fully developed than in the
Longipediidce. Mandibles very strong, with the palp generally large, biramous.
Maxillse with the outer appendages (exopodite and vibratory plate) more or less
rudimentary. Anterior maxillipeds short and compact; posterior ones of less deli-
cate structure than in the Longipediidce, and scarcely at all lamellar. Natatory
legs of somewhat varying structure in the different genera. Last pair of legs
small, biarticulate. Ovisac simple.

Remarks. The type of this family is the remarkable genus Cervinia of
Norman, the systematic position of which has been much disputed by carcinologists.
Closely allied to it is a new genus, Cerviniopsis, to be treated of below, as also
the genus Eucanuella of Scott. Finally, I am of opinion that the genus Zosime
of Boeck, though in some points differing conspicuously from the 3 above-men-
tioned genera, ought more properly to be included in the present family. All
the species belonging to this family, are true deep-water forms; and in accordance
therewith are quite devoid of visual organs. They moreover differ materially from
those of the Longipediidce in the fact that the rostral plate is quite immobile
and continuous with the cephalic shield, as also in the very different structure of
the posterior maxillipeds.

Gen. 5. CerVima, Norman, 1878.

Generic Characters. Body slender, attenuated, with very thin and flex-
ible integuments. Cephalosome distinctly defined from the 1st segment of meta-
some, lateral parts but slightly expanded, wholly exposing the oral appendages.
Epimeral plates of the pedigerous segments small, rounded; last segment rather
narrow. Urosome comparatively large, genital segment in female without any

tran>\>Tsal suture dorsally. Caudal rami long and narrow, discontiguous, each
with a small in tin- middlr of the outer edg'-. the L } middle apical seta; of a

p'-cidiar -oft con-M.'iicy. Anterior antenna' consisting "1 7 \vell-detined articu-
lations, none uf \vliieli are particularly expanded; those of male imperfectly prehen-
>ile i?i. posterior antenna' with the inner ramus verj strong, outer comparatively
small. -1-artieiilate. Mandibles \\itli the masticatory part very massive, palp com-
paratively large, with hoth raiui somewhat lamellar, and carrying thick plumose
Maxilla- without anv trace of eitl .podite or vibratory plate. Anterior

maxillipeds with the 1st hasal joint gihhously expanded hehind: posterior ones
1-articulate. last ~2 joints (constituting the terminal parti comparatively small and
armed with ^uniform seta'. 1st pair of nataton lr-s \\ith hoth rami .'J-articulate
and of iioi-mal appearance, the :> succeeding pairs with the inner ramus more or
l.'-s transformed. Last pair of le^s veiy small, with im inner expansion of the
proximal joint.

/'///"//,>.- This -cnus was established by ( 1 an>n A. M. Norman, to in-
clude a peculiar deep-water Copepod found by him off the English coast. The
miens were sent to Prof. Urady for examination, and in the well-known
.Monograph of the latter author, the genus is recorded as a member of the family
Mi,l,lii-inl<i'. This arrangement is unquestionably incorrect, as the genus does
not exhibit any very close all'inity to Mi*n/ihri<i : and Dr. (liesbrecht has also subse-
quently called attention to the unreasonableness of Brady's classification as re^anU
this genus. \\Y do not know at present with certainty more than a single species
belonging to this genus.

9. Cervinia Bradyi, Norman,
in. \i).

inntfl lliiiilin N.>I-III:III. in l!r;idy'< .Monc-r.-ipli c.i'ili.- liriii^li < ' .|p'-|..>-l:i, Vol. I. p. Mi. I'l.XXIN' A.

flgS. 3-13.

>'y ,//)> Characters. 1'^nmlc. Rody slender and elongated, with the an-
terior division >omewhat depi.--<.-d and gradually widenin.u in front. ( 'ephalovoinr
comparatively short and broad, almost truncated in front, with the rostral plate
very small, triangular. La-t segmenl of inetasome much narrower than the pre-
ceding segment. I'rox.me (comprising the caudal rami) fully as long as the
anterior division of the body, genital ^egim-nt very Large, ''quailing in length the
.'{ remaining segments combined, and sli-htlv dilated in its anterior part, but
without any lateral projections; the succeeding segments finely hairy on the ventral
and lateral faces, last segment longer than tie' preceding one and tapering dis-

21

tally; anal opercle somewhat projecting, but perfectly smooth. Caudal rami narrow
linear, about equalling in length the last 2 segments combined, and everywhere
minutely hairy, the 2 middle apical setae slightly unequal and much stronger than
the others, having the outer part minutely annulated and thickly covered with
delicate cilia. Anterior antennae almost attaining the length of the cephalosome,
and slightly attenuated, carrying strong curved setse along the anterior edge and
on the tip, the outer 4 articulations somewhat narrower than the 3 proximal ones.
Posterior antennse with remarkably strong and densely ciliated spines at the tip,
outer ranius not even attaining 1 / 3 of the length of the inner, and much narrower.
Inner ramus of the 3 posterior pairs of natatory legs (in the adult animal) con-
sisting of only 2 joints, the proximal of which, especially in the 2nd pair, is greatly
expanded, and produced at the inner corner to a strong deflexed spiniform process,
in front of which a similarly strong curved spine is attached; distal joint in this
pair produced at the tip, between the 2 innermost spines, to a similar, but smaller
process. Last pair of legs extremely small, with the distal joint scarcely longer
than the proximal one, and provided with one apical seta and 2 small lateral spines.

Body semipellucid, with a pale yellowish tinge.

Length of adult female 1.45 mm.

Remarks. I have been in some doubt about the correctness of my identifi-
cation of the above- described form with Norman's species, because the inner ramus
of the 3 posterior pairs of natatory legs in that species is described by Brady
as 3-articulate, whereas in the Norwegian form it consists of only 2 joints; but
in all other respects it so closely agrees with Brady's description, that I have
not felt justified in establishing a new species on account of this apparent difference,
which may perhaps be due to the circumstance that the specimen dissected by
Brady had not attained its full development. On the other hand, I am of opinion
that the solitary male specimen described by Dr. Giesbrecht from the Gulf of
Naples may more properly be referable to a distinct species, differing, as it does,
very conspicuously in the large size of the rostral plate.

Occurrence. Only a very limited number of specimens of this form, all
of the female sex, have hitherto come under my notice. They were taken at
different times, some off the west coast of Norway, some off the Lofoten Islands,
from considerable depths amounting to 100 fathoms.

Distribution. English and Scottish coasts (Brady, Scott).

22

Gen. 6. CerviniOpSlS, <4. 0. Sars, n.

Generic Characters. General innn of body about as in Cervinia. (Yphalo-
sorae, however, comparatively larger and imperfectly defined from tin- 1 st pedigerous
segment, its lateral parts rather deep. partly including hetueen them the oral
appendages rostral plate largr and broad at the base, Kpimeral plate. of the
HICCeeding >egments slightl\ angular. Uenital segment in female with a well-
marked transversal suture in the middle dorsally. and produced on each side of
the Miture to a recurved spinilonu projection. Caudal rami very narrow, linear,
and contiguous along their whole length, apical setje of normal appearance. An-
tei-ior antenna' very rohust. clavate. 6-articulate, and clothed with strong, partly
spmiform seta-, one of them, issuing from the end of the 4th joint, being tran^-
I'ormed in to a large, almost fusiform appendage curving backwards and clothed along
one of the edges with long cilia, this joint and the 2 outer ones very short and less
distinctly defined. Posterior antennae less robust than in CiTriniti. outer ramus
of larger si/.e, 4-articulate. Oral parts on the whole resembling in structure those
in Cervinia. Natatory legs with both rami .'{-articulate and of about equal si/.e.
Last pair of legs with the distal joint slender, linear, proximal joint quite short
and without any inner expansion. Male unknown.

A 1 - ///'///*.- --This new genus is somewhat intermediate in character between
Cervinia and Em-mini'lln. agreeing in some points more closely with the former,
in others with the latter. ^Krom both of them it differs conspicuously in the
structure of the anterior antennae, and the peculiar appearance of the caud;l rami,
which are so closely squeezed together, that they look like a single appendage.
Off the Norwegian coast occur 2 closely allied species, to be described below.

10. Cerviniopsis clavicornis, G. (). Sars, n. sp.

(PI. XII X XIII. flg. li.

Sjirci/ir ('lini-iicti'r*. Female. Body moderately slender, with the anterior
division somewhat depressed behind and widening in front. Cephalic segment
rather large and deep, exceeding in length the 1 succeeding segments combined;
rostral plate broadly triangular and slightly dellexed. Last segment of metasome
with a distinct dentiform projection on each side. I'rosome (including the caudal
rami) not quite as Ion- as the anterior division: genital segment with the lateral
spinilonn projections \ery strong and prominent. Last caudal segment abruptly
contracted towards the end, anal opercle semilunar. Caudal rami slightly e\c< rding

23

in length the last 2 segments combined, each carrying in front of the middle
outside a very small, hair-like bristle and another stronger one at some distance
from the tip, the 2 middle apical setae very unequal, the inner one more than
twice the length of the outer, both very minutely denticulate. Anterior antennse
pronouncedly claviform in shape, the 3rd joint being considerably expanded, and
arching over the short recurved terminal part. Posterior antennse with the outer
ramus about the length of the 2 outer confluent joints of the inner. Natatory
legs with both rami of normal structure. Last pair of legs with the distal joint
about 4 times as long as the proximal one, narrow linear in form, and carrying
on the tip 2 unequal spines and between them a slender seta. Ovisac of mode-
rate size, oval in form, and containing a rather limited number of large glo-
bular ova.

Colour whitish gray.

Length of adult female 1.60 mm.

Remarks. In its general appearance, this form bears an unmistakable
resemblance to Hhtcanuella splnifera Scott, to be described farther on, and
indeed, I was at first inclined to refer it to that genus. On a closer exami-
nation, however, it is found to differ in some points rather materially, the most
conspicuous difference being the peculiar structure of the caudal rami, also shown
in the succeeding nearly-allied species.

Occurrence. Several specimens of this peculiar form, all of the female
sex, were found many years ago in the 0stnses Fjord, Lofoten Islands. The
specimens were obtained by examining the loose muddy deposits taken up by the
aid of a light dredge from a depth of about 100 fathoms.

11. Cerviniopsis longleaudata, G. 0. Sars, n. sp.

(PI. XIII, fig. 2).

Specific Characters.- Female. Very like the preceding species, but of
somewhat smaller size and more slender form of body. Anterior division, seen
dorsally, of almost uniform width throughout, rostral* plate less broad. Last
segment of metasome without any lateral projections. Urosome (including the
caudal rami) fully as long as the anterior division, lateral projections of genital
segment much smaller than in C. davicornis. Caudal rami exceedingly slender
and elongated, exceeding in length the 3 last segments combined, hair-like bristle
of the outer edge occurring behind the middle. Antennse and oral parts of much
the same structure as in the preceding species. Natatory legs, however, slightly

_ _' 1

differing, 1st joint of inner ramus in the L'nd and 3rd pairs exhibiting an appear-
ance similar to that in Certnnia, the inner corner being vreatly produced, and
the natatory seta transformed in to a -troni: spine. Last pair of legs with the
distal joint comparatively less -lender than in ('. <-liirirnti*. middle apical seta
quite short.

' /'mi- whitish gray.

LI ngth of adult female 1.3(1 mm.

/.'<-//"//.>. Though very closely allied to the preceding species, this form
is unquestionably specifically distinct, diftering not only in the greater length of
the caudal rami. hut also in the smaller si/e of the lateral projections of the
nenital segment, and partly also in the structure of the legs.

Occurrence. < >nly 2 female specimens of this form have hitherto come
under my notice. They were taken from great depths oil the west coasl of Nor-
, the exact locality not being stated.

Gen. 7. Eueanuella, Scott, 1901.

Generic Cli'inn-trr*. General form of body about as in Cerviniopsis.
Cephalosome imperfectly defined from the 1st segment of metasome, and projecting
in front to a conically-pointed rostrum. Epimeral plates of the 3 succeeding
segments well developed, acutely pointed behind. Genital segment in female with
a well-marked transversal suture in the middle dorsally, and produced on each
side to a -tmng spiniform projection. Caudal rami somewhat lamellar, noncon-
tiguous. taperiim distally. Anterior antenna- distinctly 7-articulate. and edged with
ciliated seta\ one of them, issuing from the 4th joint, being much larger than the
others, the 3 outer joints abruptly much narrower than the preceding ones.
Posterior antenna' comparatively feeble] in structure than in the 'J preceding
genera, outer ramus well developed, (-articulate. Oral parts on the \\liole re-

s.'inbling those in < 't,n >iin ;\\\(] ( 'iTr'nt'iii/ivi*. Natatory legs comparatively slender,

with both rami :>-art iciilate. outer ramus of 1st pair unusually strong and much

h mirer than the inner. Last pair of legs about as in Cmwnopsis. Male unknown.

/'< ,,i<trl:s. This -eiius. established by Th. Scott, ought undoubtedly to be

referred to the I'amiU Cerviniidce, as here defined, [n several respects it exhibits,

indeed, a close resemblance to the genus ( 'i IT, ///r/y/.s/.s-, hut differs in some other
points so materially, that it ought more properly to be kept apart. The chief

25

differences from that genus refer to the structure of the anterior antennae and the
caudal rami, partly also to that of the natatory legs. We do not know at present
of more than a single species, to be described below.

12. Eucanuella spinifera, Scott.

(PL XIV).

Eucanuella spinifera, Th. Scott in 19th Report of the Fishery Board for Scotland, Part III,-
Scientific Investigations, p. 245, PL XVIII, figs. 110.

Specific Characters. Female. Body moderately slender and conspicuously
attenuated behind. Cephalic segment comparatively large, exceeding in length the
4 succeeding segments combined, and evenly vaulted above, lateral parts rather
deep, partly including between them the oral appendages, rostrum projecting
considerably. Epimeral plates of the 3 succeeding segments projecting behind in a
somewhat spiniform corner. Last segment of metasome slightly produced on each
side, but without any distinct dentiform projection. Urosome (including the caudal
rami) shorter than the anterior division, genital segment rather broad, with the
lateral projections very prominent. Last caudal segment longer than the pre-
ceding one, and gradually tapering distally; anal opercle somewhat prominent,
semilunar. Caudal rami conspicuously asymmetrical, the right one projecting con-
siderably beyond the left, and nearly as long as the last 2 segments combined^
both gradually tapering distally, and exhibiting outside, at some distance from
the base, a small spinule; dorsal face with 3 delicate bristles, 2 of which occur
near the tip, the 3rd in front of the middle; tip with only 2 setae, the inner of
which is more than twice as long as the outer. Anterior antennae with the 4
proximal joints considerably expanded, 2nd joint armed with a strong spiniform
projection issuing from the upper face and pointing backwards. Outer ramus of
1st pair of legs scarcely inferior in size to that of the succeeding pairs, and
fully twice as long as the inner. Last pair of legs with the outer digitiform
process of the proximal joint rather thick, distal joint narrow linear, with one
apical and 2 lateral setae. Ovisac comparatively small, rounded.

Colour whitish gray.

Length of adult female 1.30 mm.

Remarks. The above-described form is unquestionably identical with that
recorded by Th. Scott under the above name. It may at once be recognized
from any of the other Cerviniidce by the characteristic structure of the caudal
rami, as also by the conically-produced rostral plate.

4 Crustacea.

Occurrence. Some few specimens of this form, all of the female sex, have
been taken at different times, from depths of 50 60 fathoms. One of the spe-
cimens was found at Hanko, lower part of the Christiania Fjord, the others otf
the west coast of Norway.

. Scottish coast (Scott).

Gen. 8. ZOSime, Boeck, 1872.

Gh neric r/m/wr//r.--. Body of comparatively robust form, with the anterior
and posterior divisions, at any rate in female, well marked off from each other.
Cephalosome confluent with the 1st pedigerous segment, and produced in front to
a short and broad rostral plate. Epimeral plates of the 3 succeeding segments
w.-ll developed, sub-angular. Last segment of metasome abruptly narrower than
the preceding one. Urosome in female somewhat flattened, with the segments
more or less expanded laterally, in male more cylindrical in form. Genital seg-
ment in female with a very distinct transversal suture in the middle dorsally.
Caudal rami of moderate length, discontiguous, the 2 middle apical setse of a
soft consistency similar to those in Cn-rin/n. Anterior antennae short and stout,
densely setiferous, 6-articulate. Posterior antenna? with the outer 2 joints con-
fluent, outer ramus 3-articulate. Oral parts differing somewhat in structure from
those in the other Or/ -ii/i '/<!. Mandibles with the palp tri-lobate, inner lobe
confluent with the basal part, the other 2 constituting the 2 rami. Maxillae with
2 small knob-like projections outside the pal]). Anterior maxillipeds short and
compact, with 4 digitiform lobes; posterior ones of comparatively simple structure,
3-articulate. First pair of natatory legs much smaller than the others, with the
inner ramus bi-articulate; the 3 succeeding pairs with both rami slender, 3-arti-
culate. Lust pair of legs somewhat resembling those in the EctinosomidcB, proxi-
mal joint exhibiting inside a well-marked setiferous expansion, distal joint im-
|H -fleetly defined.

//(///"//..-.This genus, established by Boeck, was considered by th.it
author. a> .il-o by Prof. Brady, to be most nearly related to the genus Ectinosornu.
\\hirh in the present Account is regarded as the type of a distinct family, Ecfi-
<//'"/". < >n .1 close) examination, however, I find that it should more properly
be referred to the family ('frrininln 1 , as here defined. True, the last pair of legs,
as also the posterior m;txilliped. exhibit some resemblance to those in the genus

27

Ectinosoma; but in all other respects this genus is very different, and apparently
more nearly related to the 3 preceding genera. We do not know at present with
certainty more than a single species belonging to this genus.

13. Zosime typiea, Boeck.

(PL XV).

Zosime typiea, Boeck, Nye Slsegter og Arter af Saltvandscopepoder. Chr. Vid. Selsk. Forhandl.

1872, p. 46.

Specific Characters. Female. Body rather short and stout, somewhat
depressed, with a very conspicuous constriction in the middle. All segments
having the posterior edge distinctly denticulate dorsally, the denticles of the penulti-
mate caudal segment being in particular very coarse and partly bifid at the tip.
Cephalic segment rather large, considerably exceeding in length the 3 succeeding
segments combined, rostral plate short and broad, blunt at the tip, and carrying
2 small apical bristles ; the 3 succeeding segments with the epimeral plates some-
what exstant laterally. Last segment of metasome abruptly much narrower than
the preceding ones, and produced on each side to a slight dentiform corner.
Urosome (including the caudal ranii) about the length of the anterior division,
its 3 anterior segments forming on each side well-marked lamellar expansions
each terminating in an acute recurved corner; last segment very small. Caudal
rami about 3 times as long as they are broad, slightly constricted at the
base, and transversely truncated at the end. outer edge finely denticulate and
carrying, at some distance from the tip, a small bristle; the 2 middle apical seta3
rather coarse and very unequal, the inner one twice as long as the outer, and
exhibiting near the base a peculiar angular bend. Anterior antennae with the
2nd joint much the largest, and equal in length to the succeeding 4 joints com-
bined. Posterior antennae with the outer ramus somewhat shorter than the inner.
Last pair of legs with the inner expansion triangular and carrying 3 slender setae,
distal joint not distinctly defined from the proximal one, truncated at the tip and
provided with 3 apical and one lateral seta.

Colour whitish gray.

Length of adult female 0.55 mm.

Remarks. It seems to me somewhat questionable, whether the form de-
scribed under this name by British authors (Brady, Scott) is in reality identical
with Boeck's species. Prof. Brady, for instance, indicates the length of the animal
to be 0.80 mm., whereas the largest of my Norwegian specimens only measures

0.55 mm. in length; and further the h'gures of the animal given by that author
and by Th. Scott do not fully agree with the form examined by me. Finally,
on comparing my drawings with those given by the above-named authors, I also
find some differences in the structural details.

Occurrence. I have found this form occasionally in the upper part of the
Christiania Fjord in depths of about 16 fathoms, muddy bottom. The specimen
\amined by Boeck was likewise from that locality.

/' ttribution.? British Isles (Brady, Scott).

Fam. 4. Ectinosomidae.

( 'hurrt< /*. Body of a peculiarly smooth appearance, and more or less
fusiform in shape, with no very conspicuous demarcation between the anterior and
posterior divisions. Cephalosome wholly confluent with the 1st pedigerous segment.
and produced in front to a more or less prominent rostral plate continuous with
the cephalic shield. Epimeral plates of the 3 succeeding segments well developed.
Last segment of metasome without such plates. Urosome consisting in female of
\. in male of 5 segments, the last one generally small and more or less cleft at
tin- end. Caudal rami discontiguous, divergent, with the 2 middle apical seta?
more or less elongated. No true eye present. Anterior antennae comparatively
-mall, and composed of a limited number of articulations. Posterior antennae
with strong denticulated spines at the tip, outer ramus slender, 2- or 3-articulate.
< >ral parts differing rather greatly in their structure from those in the preceding
f:imilie-. Natatory legs powerfully developed, with both rami 3-articulate and
densely spinous. Last pair of legs lamellar and edged with strong spiniform set;e.
Ovisac single.

Hi-murk*. This family, the type of which is the genus Erl'unwniiii of Boeck,
\liibits several well-marked differences from the preceding ones, both as regards
the external appearance ;md the structural details; ami as there are several genera,
which so far closely agree \\itli each other, the establishment of this new family
may be fuliy justified. It comprises as yet 4 genera, all of which are represented
in the fauna of \ur\\ay.

Misophriidae

Copepoda

Harpacticoida

PL!

.. /or

G.O. Sars autogr.

Misophria pallida, Boeck

Tryklidi" private Opmaaling Chra

Misophriidae

Copepoda

Harpacticoida

6.0. Sars autoqr.

Misophria pailida, Boeok
(continued)

Trykii den private Jpmaaling Chra

Longipediidae

Copepoda

Harpaciicoida

P1I.

G.O. SaTS autogr.

frykti den private Qpmaating Chra

Longipedia coronata ; Glaus

Longipediidas

Copepoda

Harpacticoida

H.IV

III- I
/ III '

'm

^iMfc

6.0. Sars autogr.

Longipedia coronata, Glaus
(continued)

Tryktiden private Optnaaling.Chra

Longipediidae

Copepoda

Harpacticoida

:

G.O Sars autogr.

1 Longipedia Scotti G.O. Sars

2 Longipedia minor, Scott

I-vM i den private Opmaalinq ChrA

Longipediidae

Copepoda

Harpacticoida

pirn.

G Sars autogr

Sunaristes paguri, Hesse

Trykriden private Opmaaltng.Chra

Longipediidas

Copepoda

Harpaciicoida

HA/K.

\

G Sars autogr

Tryktiden privrte Opmaaling Chr&

Sunaristes paguri, Hesse
(continued)

Longipediidas

Copepoda

Harpacticoida

P1.W

x-.

;- /

6.0. Sars avitogr.

Canueila perpiexa, Scott.

Tryktiden privale Opmaaling.Chra

Longipediidae

Copepoda

Harpacticoida

a*

G.O Sars autogr.

Canuella perplexa, Scott
(continued)

Trykl i den private

Longipediidae

Copepoda

Harpacticoida

HX

t

i -

/

-^4 MMiM.

ifWTP'***.**'/? I V-' S 'J i I

a^&fe ; .

I //

4 /

G.O. SaTS autogr.

Tryktiden private

Canuella furcigera, G.O.Sars

Cerviniidae

Copepoda

Harpaciicoida

PXT

-A

f-
\

I
H

-

^ ^feJ

?

G.O. Sars autogr.

Cervinia Bradyi^ Norman

CerviniidaB

Copepoda

Harpacticoida

PlXtt

6.0. SaTS autogr.

Tryktiden private Opwaaling,Chra

Cerviniopsis clavicornis, - G Sars

Cerviniidae

Copepoda

Harpaciicoida

P1M

s

.

' '

GO Sars autogr. Trykfiden pnvat* Opmaalinj.Chra

1 Cerviniopsis clavicornis, G Sars
(continued)

Cerviniidae

Copepoda

Harpacticoida

6.0. Sars autogr.

Eucanueiia spinifcra, Scott.

Cerviniidae

Copepoda

Harpaciicoida

PLW

'.ogr.

Zosime Tvpica Boeck

Tryktiden private

Ectinosomidas

Copepoda

Harpacticoida

HXVC

6.0. Sars autogr.

Ectinosoma Sarsi, Boeck

Ttyktiden private Opmaating,Chra

AN ACCOUNT

OF THE

CRUSTACEA

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS III & IV

ECTINOSOMID^E, HARPACTICID.E

(PART)

WITH 16 AUTOGRAPHIC PLATES

BERGEN

PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMERMEYER/S FORLAG, CHRISTIANIA

1904

29

Gen. 9. EctillOSOma, Boeck, 1864.

Generic Characters. Body more or less slender, pronouncedly fusiform
in shape, with the anterior division scarcely broader than the posterior. Ce-
phalic segment gradually attenuated in front, and produced to a tongue-shaped
hyaline rostral plate, arching over the bases of the anterior antennae; lateral parts
not very deep, almost wholly exposing the oral appendages. Epimeral plates of
the 3 succeeding segments acute-angular behind. Last segment of metasome scarcely
narrower than the preceding segment. Urosome gradually attenuated behind,
genital segment without any trace of a transversal suture in the middle, last
segment rather small and more or less deeply cleft. Caudal rami comparatively
short, diverging, the 2 middle apical setse closely juxtaposed and considerably
thickened at the base. Anterior antennae rather small, 5 7-articulate, and clothed
with slender setse. Posterior antennae with the outer 2 joints confluent, outer
ramus much more slender than the inner, and distinctly 3-articulate. Anterior lip
compressed and more generally projecting in front to an acute recurved point.
Mandibles sharply curved, with ihe masticatory part deeply cleft and armed with
a limited number of simple teeth, outside which is attached a thickish seta; palp
comparatively large, with the basal part much elongated, both rami uniarticulate,
the inner one abruptly recurved and tipped with long setae, outer ramus compara-
tively small. Maxillae with the masticatory part armed with 3 or 4 strong, claw-
like spines, palp divided into several setiferous lobes. Anterior maxillipeds con-
sisting of 2 thickish basal joints, very movably articulated the one to the other,
terminal part rudimentary, carrying 2 slender, claw-like spines curved anteriorly.
Posterior maxillipeds issuing inside the anterior, slender, straight, 3-articulate,
middle joint narrow and elongated, terminal joint small, tri-setose. First pair of
natatory legs scarcely smaller than the others, with the inner ramus longer than
the outer. Last pair of legs closely approximate, and each consisting of 2 well-
defined joints, the proximal one forming inside a large lamellar expansion carrying
2 spiniform setae, distal joint trilobate, each lobe tipped with a similar seta.

Remarks. This genus was established in the year 1864 by Boeck, to
include 3 Norwegian species, one of which, E. melaniceps, is perhaps identical
with the form recorded by Baird as Canthocamptus minuticornis (Miiller). Subse-
quently several new species have been added, chiefly by Prof. Brady and Th. Scott.
The latter author, in his interesting Revision of the British Species of the Genera
Bradya and Ectinosoma, records no less than 13 different species belonging to
the present genus, and nearly the same number have been observed by myself off

_ 30

the Norwegian coast. The species arc ratlin- difficult to distinguish from one
another, en accnimt of their rather uniform external appearance, and the ge-
nerally small size and inconspicuous colour of the animal. Two of the best
distingishing characters arc undoubtedly the structure of the last pair of legs and
the relative length of the set:e with which they are fringed. In these characters
there are scarcely two species which fully agree with each other. All the species
have in common the peculiarity that the specimens remain floating on the surface
of the \\ater. when they come in contact with it. a circumstance which essentially
facilitates the collecting of them from any mud brought up by the aid of the dredge.

M. Ectinosoma Sarsi, Boeck.

ll'l. XVI).

Sarsii, r->-k. N;. M.-'-^-ter og Arter af SultvaiulseopriMxl.-r. Chr. Vid. Selsk. For-

liaudl. 1872, ].. l.\
Syii: EctinOSOma .-/'/'///'/'ex. linuly.

Sj,,,-i(ir Characters. Female. Body somewhat robust, fusiform, greatest
width excelling '/ 5 of the length, and occurring somewhat in front of the middle.
Cephalic segment about equalling in length the 3 succeeding segments combined,
r<tral plate evenly rounded at the tip. Urosome only slightly exceeding in length
the exposed part of metasome, posterior edge of the segments densely fringed
with delicate spinules. Caudal rami comparatively short, scarcely longer than the
last segment, apical setse not much elongated, the innermost but one about equal
in length to the urosome exclusive of the caudal rami. Anterior antennae short
and thick .~i-articulate. Posterior antennae with the outer ramus almost as long
as the inner, middle joint very small. Anterior lip with an acute recurved process
in front. Natatory h gs with the rami rather broad, all the spines coarsely
denticulate, setse very strong. Last pair of legs sub-quadrangular in outline, inner
expansion of the proximal joint rather narrow and extending almost as far as
the distal joint, the latter somc\\liat longer than it is broad, and exhibiting on
the lower side, near the base, a transverse row of 4 small denticles, immediately
below which a slender bristle is attached; marginal spines of both joints unusually
short, not extending beyond the middle of the genital segment.

Mody of an uniform pale \ello\\ish 1m,., ,,r straw-coloured.

Lenu'th of adult female reaching to !..")( mm.

/'' narfa. This is the largest of all the known species, and may more-
over in the living state be rer.^iii/ed by its pale yellow colour. The structure
of the last pair of le^s i> also characteristic from the unusual shortness of the

31

marginal spines. The E. spinipes of Brady is unquestionably identical with
Boeck's species.

Occurrence. I have found this form not unfrequently in the upper part
of the Christiania Fjord, as also in the Trondhjem Fjord, in depths ranging from
10 to 20 fathoms. Mr. Scott records it also from Finmark.

Distribution. British Isles (Brady, Scott), coast of France (Canu), Novaya
Zenilia, Spitsberg (Scott).

15. Eetinosoma neglectum, G-. 0. Sars, n. sp.

(PI. xvir, fig. i).

Specific Characters. Female. Very like the preceding species, but of
somewhat smaller size and less robust form of body. Cephalic segment about
the length of the 4 succeeding segments combined, and gradually narrowed in
front, rostral plate evenly rounded at the tip. Urosome considerably longer than
the exposed part of the metasome, posterior edges of the segments very finely
spinulose. Caudal rarni somewhat divergent, nearly twice as long as they are
broad, apical setae not much elongated. Anterior antennae resembling in structure
those in E. Sarsi, being rather robust and 5-articulate. Anterior lip with an
acute recurved projection in front. Last pair of legs somewhat resembling those
in E. Sarsi, but with the distal joint more unequally trilobate, the outermost lobe
occurring considerably farther forward than the innermost, marginal setae both
of this joint and the inner expansion of the basal one much more elongated,
partly extending beyond the genital segment.

Male considerably smaller than female, and easily recognizable by the
prehensile character of the anterior antennae, and by the subdivision of the genital
segment.

Colour light brown or corneous, with dark reddish shadows in front.

Length of adult female 1.30 mm., of male 0.70 mm.

Remarks. This form is closely allied to E. Sarsi, and has most prob-
ably been confounded with it by other authors. On a closer comparison, it is
however found to differ rather markedly in the structure of the last pair of legs,
the marginal setae of which are much more elongated. In the living state it is
moreover at once distinguished from that species by its different colour.

Occurrence. I have met with this form rather abundantly in several
places of the Norwegian coast, from the Christiania Fjord to Vadso. It is gene-
rally found in depths ranging from 10 to 20 fathoms, muddy bottom. No doubt
it will also be found to occur out of Norway.

32

if,. Ectinosoma propinqvum, Scott.

(PI. XVII, rig. 2).

,'. Tli. & A. Scott. 1J. -\i-ion of thf Hritish (\.p.-po. hi belonging to the genera

i:r;n!\.i :in>l BctfflOBOma; I'ran-act. Linn. Soc. London, Vol. VI. I':irt .">, p. 4_>8, PI. 36, figs. 19,
_'7. \>\: I'l. 37, figs. i'. !.'. 32, 65; PI. :w, ti-s. 9, 23, 34, o4.

Specific Cli<tiiirtri-x. /'/ ni'ilf. General form of body resembling that of
the 2 preceding species. Cephalic segment, however, seen clorsally, more abruptly
runtrarted in front, with the rostral plate more horizontal and narrowly spoon-
shaped. I 'rusunie comparatively shorter and less attenuated behind. Caudal rami
\ery short. scarcely as long as they are broad, and considerably divergent. An-
terior antenna\ as in the 2 preceding species, 5-articulate and rather stout.
Anterior lip with a very acute recurved projection in front. Last pair of legs
comparatively small, with the marginal spines unusually short, not extending beyond
the middle of the genital segment.

Colour dark corneous.

Length of adult female 0.86 mm.

/.'< ///"//>. I think I am right in identifying the above-described form with
Scott's E. />r]ii>/i/rti,,i. with which it seems to agree fairly well in most of the
anatomical details, though being somewhat inferior in size. It is closely allied
to I-', in <ili rfiini. and may easily be confounded with that species. On a closer
examination, however, it is found to differ, not only in its much inferior size,
but also in the narrowly e\serted and spoon-shaped rostral plate, the much shorter
caudal rami. and the structure of the last pair of legs, which, in the shortness
of the marginal spines, more resembles that in E. Xr*i.

Occurrence. I have found this form in 2 widely distant localities, viz.,

at Hvulor, lower part of the Ghristiania Fjord, and in the Trondhjem Fjord at

lemes and Bejaii. the depth ranging from 3 to 20 fathoms. Mr. Scott also

rerun]- it li-uin Kinmark, and it thus seems to occur along the whole Norwe-

gian roa-t.

/>/>//;///;//. -Firth of Kurth (Scott. Ceylon (A. Scott).

17. Ectinosoma elongatum, G. <). Sars, n. sp.

MM. XVIII. HIT. 1).

finmarchicum t

S/,,ri/ir ( 'Imnirfn-s Female. I'.ody extremely slender and elongated,
with the cephalic segment, seen dorsally, abruptly contracted in front, rostral

plate narrowly spoon-shaped and nearly horizontal. Caudal rami of moderate
size, about equalling in length the last segment, and tapering somewhat distally,
apical seta? not very divergent. Anterior antennae more slender than in the 3
preceding species, and composed of 6 well-defined articulations. Anterior lip
obtusely rounded in front, without any trace of a recurved projection. Natatory
legs comparatively more slender than in the 3 preceding species. Last pair of
legs of moderate size, with the distal joint rather broad and somewhat oblique,
apical spines slender, setiform, and rather unequal, the innermost being much
shorter than the other 2, inner expansion of proximal joint with a transverse row
of delicate spinules at the base, outer seta much shorter than the outermost one
of the distal joint.

Colour pale yellowish.

Length of adult female 0.88 mm.

Remarks. This is a very slender species, and in so far resembles a form
briefly recorded by Th. Scott from Finmark under the name of E. finmarchicum.
It is, however, of somewhat smaller size, and moreover, to judge from the figures
given, seems to exhibit some difference in the structure of the last pair of legs
and in the inter-relative length of their marginal spines.

Occurrence. The only locality where I have hitherto met with this form,
is at Selven, near Agdenses, Trondhjem Fjord. It here occurred not unfrequently
in a depth of 3 6 fathoms, muddy sand.

18. Ectinosoma Herdmani, Scott.

(PI. XVIII, fig. 2).

Ectinosoma Herdmani, Th. & A. Scott, Revision, &c. p. 432, PI. 36, figs. 16, 44; PI. 37, figs. 3,

16, 29, 54; PL 38, figs. 7, 25, 33, 47.

Specific Characters. Female. Body slender, sublinear in form, with the
cephalic segment, seen dorsally, considerably attenuated in front, rostral plate
narrowly exserted, spoon-shaped. Caudal rami very short, not nearly as long as
they are broad, apical seta? somewhat divergent. Anterior antennae slender, 6-ar-
ticulate. Anterior lip obtusely produced in front. Last pair of legs comparatively
small, with the marginal spines short and thick, all of about the same size.

Colour whitish, semipellucid.

Length of adult female scarcely exceeding 0.60 mm.

Remarks. This form, first described by Th. & A. Scott, somewhat re-
sembles E. elongatum in the general form of the body, but is rather inferior in

5 Crustacea.

!x distinguished l.y the iiim-li shorter caudal rami and
: ili.- last pair of ICL'-.

l-.-und ,, nally, t"irether with A', ekngatum, at Selven.

,: Tananger, south coast ol Norway,
[nth ..f Forth. Me ol Man (Scott).

L9. Ectinosoma melanieeps, Boeck.

(I'l. XIX. ti- I).

,1.- \.<! N-.r-.-s K\M,r ia-ttagne Copepoder. Chr.
Vi.l. S.-lsk. K.'i-li. !*;. I'. 80.

'li-n-inHi'tus mtftuMcOrntt, liainl (Ui't .Miill'Tl.

I-', null,. Body moderately slender, subfusiform in

tpe, \vith thf iTphalir M-iiini-iit. N,.,-II d>rs:illy. .gradually contracted in front.

i.tu-.-l\ ruiind.-d .-it the tip. Caudal rami about as long as they

I. innnniiist apical s-ta m<>r' i-lniiL'atfd than in most other species.

n- antriina- rathiT sh-ndt-r and at tt-nuatiMl. composed of 7 well-defined

Ant.-iK-i lip with an angular projection in front. Last pair of legs

iinidrr listal joint comparatively broad and somewhat oblique, with the

apiral -pin.-s si, nd. -r. -. 'tito rm and rather micipial. appendicular bristle issuing

:u tin- margin ln-t\\crii the '1 outiTmoM >|iines; inner expansion of proximal

juint i-omparatni-ly small, with tin- inner apical spine quite short and remarkably

brn;id. lam iM.latr in fnnu. and coar>ely srrratc on the edges.

IIP L'layish white, with a very conspicuous dark shade occupying the

: part i.f the cephalie segment.

I.eiiL'th nf adult leinale n.H."> mm.

/' I' -'-ins t" me \ri-\ probable thai the form recorded by Baird

- the present spei'ie>. As, however, the identification

i m with ' " >i." of ( >. Kr. Midler cannot properly be ac-

spi-cp-s must hear the name pri.pn^cd t'oi' it by Hoeck. It is easily

' ; >le from an\ oi the other -| l.y the dark-coloured cephalic segment,

which indeed has -i\en ris.- to the sprciiie name assigned to it by

The i ir of Ir^s also exhiliit srveral peculiarities in their structure.

I i- l"im is \cr\ common ahm- the whole south and west

rwa\ in i-omparati\e]y shallow \\ater amoiiL' alga-, and may be easily

in sjut,. oi its small s )/r . i,\ the dark-coloured anterior part of the body.

" oti.. of th- pi.-, nt genus, "n touching the surface of the

35

water, it remains floating upon it, and may thus easily be picked up from any
freshly-taken sample.

Distribution. British Isles (Brady, Scott), Spitsbergen (Scott).

20. Eetinosoma Normani, Scott.

(PL XIX, fig. 2).

Eetinosoma Normani, Th. & Scott, Eevision, c., p. 435, PL 36, figs. 21, 29, 39; PL 37, figs. 12,

26, 34, 51 ; PI. 38, figs. 5, 18, 42, 45.

Specific Characters. Female. Body somewhat more robust than in E.
melaniceps, with the cephalic segment, seen dorsally, evenly contracted in front,
rostral plate short aud obtuse at the tip. A bright red pigmentary patch present
on each side of the cephalic segment, just within the lateral edge and between
the insertions of the anterior and posterior antennae. Caudal rami of about the
same appearance as in E. melaniceps, but with the innermost apical seta consider-
ably shorter. Anterior antenna? likewise very similar in structure, though perhaps
a little shorter. Anterior lip with an acute recurved projection in front. Last
pair of legs not unlike those in E. melaniceps, distal joint, however, comparatively
narrower, with the innermost apical spine longer, extending about as far as the
outermost, appendicular bristle, as in E. melaniceps, issuing from the margin
between the 2 outermost spines ; inner expansion of proximal joint with the outer
spine more slender and only very slightly lanceolate.

Colour uniformly whitish grey.

Length of adult female 0.55 mm.

Remarks. The above-described form is unquestionably that recorded by
Messrs. Th. & A. Scott under the name of E. Normani. At first I believed it to
be E. erythrops of Brady, on account of the very conspicuous red pigmentary
patches occurring within the lateral edges of the cephalic segment in front. But
Messrs. Th. & A. Scott describe as Brady's species a very different form, un-
known to me, though apparently referable to the Fauna of Norway, having been
recorded by one of these authors from Finmark. The species here under discussion
is nearly allied to E. melaniceps, though at once distinguished by its uniform
colour and the very conspicuous red ocular patches in front. It is also rather
inferior in size.

Occurrence. Only 2 specimens of this form have hitherto come under
my notice. They were both taken in the upper part of the Christiania Fjord

36^

from a depth of about 6 fathoms, muddy bottom. Th. Scott records this form
also from Vadso. Finmark.

I)itrilnit',,,n. Firth of Forth, Barrow Strait (Th. Scott), Ceylon (A.Scott).

21. Ectinosoma curticorne, Boeck.

(PI. XX, fig. 1).

/>/ "n iusnm >-H,-t'u-oriic. Boeck, Nye Sltegter og After af Saltvandscopepoder. Chr. Vid. Selsk.

Forh. 1872, p. 45.

- ('Imrm-trrx. fa-male. Body moderately slender, fusiform in shape,
greatest width in front of the middle. Cephalic segment, seen dorsally, evenly
i-Miitraeted in front, rostral plate comparatively short and bluntly rounded at the
tip. Caudal raini nearly twice as long as they are broad and slightly divergent.
Anterior antenna? very short, though composed of 6 well-defined articulations, the
Nt (if which exhibits inside a very conspicuous dark pigmentary patch. Anterior
lip with a blunt prominence in front, clothed at the hind edge with long cilia.
Last pair of legs well developed, clothed on the lower face with several trans-
verse rows of delicate spinules, distal joint somewhat unequally trilobate, apical
-pinex \ery slender and elongated, setiform, the innermost one longer than the
outermost; inner expansion of proximal joint extending about to the middle of
the distal joint.

Colour dark brown or corneous.

Length <>t' adult female 0.70 mm.

/,'< murk*. This form, first recorded by Boeck, may be easily distinguished
from any of the preceding species by the unusually short anterior antennas and
the very conspicuous dusky pigment-patch inside the 1st joint of the latter.
The form of the anterior lip and the structure of the last pair of legs are also
rather characteristic. In the opinion of Th. Scott, the Bmdya Edirftnkii of
Ricard is identical with this species.

Occurrence. Only very few specimens of this form have hitherto come
under my notice. Tiny were all of them taken in the upper part of the Christi-
ania Fjord in a depth of 6 20 fathoms, muddy bottom. The specimen observed
by Hoerk was also from the Christiania Fjord. Th. Scott, however, records this
form from 2 localities of the, Finmark coast, viz., Biigo Fjord and Vadsti.

/>i~t,-il,,iti,,)i. Scottish coast (Scott), Spitsbergen (Scott).

37

22. Ectinosoma gothiceps, Giesbrecht.

(PL XX, fig. 2).

Ectinosoma gothiceps, Giesbrecht, Die freilebenden Copepoden der Kieler Fohrde, p. 106, PI. I,

figs. 3, 12; PI. IV, figs. 17, 35; PI. V, fig. 3; PI. VII, fig. 8; PI. VIII, figs. 10, 11; PI. IX, fig. 17;

PL X, figs. 10, 21; PI. XI, fig. 13; PL XII, figs. 6, 10.

Syn? Ectinosoma pygmoeum, Scott.

Specific Characters. Female. Very like the preceding species, but of
much smaller size and somewhat less slender. Cephalic segment, seen dorsally,
evenl} 7 contracted in front, rostral plate of moderate size and obtusely acuminate
at the tip. Caudal rami very short, not nearly so long as they are broad. An-
terior antennse short, 6-articulate, resembling those in E. curticorne, but without
any pigmentary patch inside the 1st joint. Anterior lip with a short acute pro-
jection in front. Last pair of legs comparatively smaller than in E. curticorne,
but with the marginal spines very long and considerably thickened at the base;
distal joint shorter and less unequally trilobate than in the above species, outermost
apical spine considerably longer than the innermost; inner expansion of proximal
joint very short.

Colour whitish gray.

Length of adult female 0.45 mm.

Remarks. The above-described form is unquestionably that recorded by
Dr. Giesbrecht as E. gothiceps, and I am also of opinion that the E. pygmceum
of Scott is referable to the same species. It is closely allied to E. curticorne,
but of much inferior size, and is moreover distinguished by the short caudal rami,
the absence of the pigmentary patch on the anterior antennae, and also by the
somewhat different structure of the anterior lip and the last pair of legs.

Occurrence. I have met with (his small species occasionally in several
places both on the south and west coasts of Norway, as also in the Trondhjem
Fjord, in moderate depths.

Distribution. Kiel Bay (Giesbrecht), Firth of Forth, Isle of Man (Scott).

23. Ectinosoma mixtum, G. 0. Sars, n. sp.

(PL XXI, fig. 1).

Specific Characters. Female. Body moderately slender, with the cephalic
segment, seen dorsally, gradually contracted in front, rostral plate well developed
and somewhat deflexed, narrowly rounded at the tip. Caudal rami about as long

38

as they an- broad, apical setae rather slender. Anterior antennae comparatively
short, though longer than in the -2 preceding species, and composed of 6 arti-
culation^. Anterior lip with a small recurved projection in front. Last pair of
legs of moderate size, with the marginal spines very unequal, distal joint much
longer than the proximal one and subquadrangular in form, innermost apical
spine very short, appendicular bristle, as in most other species, remote from the
margin: inner expansion of proximal joint extending almost to the tip of the distal
joint, outer spine remarkably thickened, somewhat resembling that in E. melani-
>/*. though considerably more elongated.

Colour grayish white.

Length of adult female 0.58 mm.

/A nun 7.-.V. I cannot identify this form with any of the species described
by Messrs. Th. iv; A. Scott. The specific name here proposed refers to the some-
what mixed characters, some of which resemble those of E. ctoitconie, and some

those of A,', iiii'ltniirt j,*.

On-ill ,; nee. Only some few specimens of this form have hitherto come
under my notice. They were taken in the upper part of the Christiania Fjord,
near the town, in a depth of about 3 fathoms, muddy bottom.

24. Ectinosoma brevirostre, (T. 0. Sars, n. sp.

(PL XXI, fig. 2).

Body comparatively slender and somewhat
compressed, with the cephalic segment, seen dorsally, but slightly contracted in
ti'.nt. rostral plate remarkably short and blunt at the tip. Caudal rami longer
than they are broad, and somewhat obliquely truncated at the tip, apical setae of
moder.-ite length. Anterior antenna?, more slender and attenuated than in E. mix-
lii'ni. but, as in that species, 6-articulate. Anterior lip with a similar acute
recurved projection in front. Last pair of legs with the proximal joint rather
lar.L'e and broad, distal joint considerably shorter, being scarcely longer than it
is broad, imiermo-t Apical spine exceeding half the length of the outermost one,
appendicular bristle issuing near the margin; inner expansion of proximal joint
nely extending beyond the middle of the distal joint, and exhibiting at the
b:i-e an oblique transverse row of delicate spimiles. outer apical spine of quite
normal appearance.

' ',!!, yellowish gray.

Length of adult female <>.nf) mm.

39

Remarks. This new species is chiefly characterised by the unusually short
rostral plate, a character which has given rise to the specific name here proposed.
In its general appearance it somewhat resembles E. gracile, Scott, the body being,
as in that form, considerably compressed. It differs, however, very markedly in
the structure of the anterior maxillipeds, which is quite normal, as also in that
of the last pair of legs.

Occurrence. Only a single, but well-preserved ovigerous specimen of this
form was found last summer at Bejan, outer part of the Trondhjem Fjord, in a
depth of 2030 fathoms.

25. Ectinosoma gracile, Scott.

(PI. XXII, fig. 1).

Ectinosoma gracile, Th. & A. Scott, Revision, p. 429, PI. 36, figs. 18, 37; PI. 37, figs. 13, 28, 45;

PI. 38, figs. 3, 27, 30.

Specific Characters. Female. Body exceedingly slender and much com-
pressed, seen dorsally, almost linear in form. Cephalic segment evenly contracted
in front, rostral plate somewhat deflexed and blunt at the tip. Caudal rami about
as long as they are broad, apical setse rather slender. Anterior antennaB com-
paratively slender and attenuated, though composed of only 6 articulations, the
penultimate one being very narrow and elongated. Anterior lip with the usual
recurved projection in front. Anterior maxillipeds unusually powerful, with the
2nd basal joint more than twice as long as the 1st, and considerably dilated at
the base, apical claws very slender and minutely denticulate. Last pair of legs
comparatively small, but with the marginal spines rather elongated, distal joint
regularly trilobate, with the innermost apical spine longer than the outermost;
appendicular bristle some distance from the margin; inner expansion of proximal
joint unusually short.

Colour whitish gray.

Length of adult female 0.55 mm.

Remarks. This is a rather anomalous form, differing, among other things,
from the other known species of this genus very markedly in the structure of the
anterior maxillipeds. I have been enabled to prove the identity of this form
with that described by Mr. Scott, by comparing it with some specimens kindly
sent to me by that author.

c. SOUK- i'c\\- specimens nt' this form were found last summer
in the Trondhjcm Fjord, at Agdeiues. They occurred in a depth of about 50
athonis, "ii a bottom consisting cf coarse s : ,nd.

Distribui Firth of Forth. Me of Man (Scott).

Gen. i<>. Pseudobradya. G. 0. Sars, n.

Syn: Brmli/fi, Scott (part).

(' /// ric ( 'Itunn-t, /-.-. General form of body resembling that of Ectinosoma,
being more or less pronouncedly fusiform. Caudal rami often much elongated.
Anterior antenna' comparatively short, with the proximal joints more or less ex-
panded. Posterior antenna' with the outer ramus poorly developed and in some
cases consisting of only 2 joints. Anterior lip not forming any projection in front.
Mandibles and maxilla' resembling in structure those in ft-tini>*i>in<t. Anterior
maxillipeds generally very small, with the 2 basal joints bent at almost a right
aiiL-lc. terminal part consisting of 3 well-defined, though very short joints carrying
comparatively short setae. 2 of which are generally spiniform. Posterior maxil-
lipeds le-.s Render than in l-j-lnin*i>Di. Last pair of legs generally very large,
lamellar, though somewhat varying in shape in the different species, distal joint
ahvay^ well developed, appendicular bristle in some cases very strong and issuing
from the lower face of the proximal joint.

/A ///",/>. This new genus is established to include a number of species
referred by Mr. Scott to the genus Ilr<i<li/n of Boeck, chiefly on account of some
similarity in the structure of the posterior maxillipeds. These appendages are,
ho\\c\er. in reality not nearly so powerfully developed as in Brartya, and on a
clo^-r comparison, several other differences in the anatomical details are found
to exist, which would seem to warrant the establishment of a separate genus,
-oinewhat intermediate in character hetween A'l-fiiiovuittti and I>r<t<li/<i. Among these
ditlen-iici-s may lie mentioned the poor development of the outer ramus of the posterior
antenna-, the somewhat ditlereiit shape of the posterior maxillipeds and the very
hiL'hlv de\e|u|,.-d last pair of h The caudal rami, moreover, in most of the

Species, arc unusually prolonged, and the general form of the body is rather unlike
that in Hi-mli/n. and much more resembling that in l-j-ti ni^nnui . Of the 5 species
.! scribed by Mr. Sc,,;t and referable to the present genus, I have succeeded in
tinding '2 olf the Norwegian toast, and also .1 :;rd species which I regard as

lK-\\ to scie|.

41

26. Pseudobradya minor (Scott).

(PI. XXII, fig. 2).

Bradya minor, Th. & A. Scott, Eevision, p. 425, PL 35, figs. 5, 9, 13, 21, 24, 31, 35, 42; PI. 36,

figs. 5, 9.

Specific Characters. Female. Body unusually short and stout, pronoun-
cedly fusiform, with the greatest width in the middle. Cephalic segment, seen
dorsally, gradually tapering in front, rostral plate prominent, nearly horizontal,
and obtusely acuminate at the tip. Caudal rami of moderate size, scarcely longer
than they are broad, apical seise not much elongated. Anterior antennae somewhat
less abbreviated than in the other species, and composed of 6 well-defined arti-
culations, the 1st of which exhibits inside a very conspicuous dark pigmentary
patch. Outer ramus of posterior antennse about the length of the 1st joint of the
inner, and very narrow, 3-articulate. Anterior lip quite evenly rounded in front.
Anterior maxillipeds with the 2nd basal joint somewhat longer than the 1st.
Natatory legs rather strongly built. Last pair of legs of moderate size and
clothed on the lower face with several rows of delicate spinules, marginal spines
not much elongated and but slightly unequal; appendicular bristle normal, issuing
from the lower face of the distal joint; the latter oval in form, with the outermost
lobe occurring far in front of the innermost; inner expansion of proximal joint
comparatively short, scarcely extending to the middle of the distal joint.

Colour yellowish brown.

Length of adult female 0.54 mm.

Remarks. The above-described form is unquestionably identical with that
recorded by Mr. Scott as Bradya minor. It may easily be recognized from any
of the other species by the unusually short and robust form of the body, and by
the very conspicuous black pigmentary patches inside the 1st joint of the anterior
antennse.

Occurrence. Some specimens of this form were found last summer in
the Trondhjem Fjord, at Selven, near Agdenses, in a depth of 3 6 fathoms,
muddy sand.

Distribution. Firth of Forth, Liverpool Bay (Scott).

27. Pseudobradya acuta, G. 0. Sars, n. sp.

(PI. XXIII, fig. 1).

Specific Characters. Female. Body rather slender, subfusiform in shape,
with very thin and soft integuments. Cephalic segment, seen dorsally, considerably

6 Crustacea.

42

mntracted in front, with the rostral plate nearly horizontal and terminating in
;i \,i\ arutt- point. Urosome rather massive and but slightly attenuated behind.
i.lal ranii comparatively large and broad, about twice as long as the last seg-
iii. -nt. apical setffl slender and elongated. Anterior antenna? very short, 6-arti
culate. with tin.- proximal joints considerably expanded. Posterior antennas with
the outer ramus very narrow, .'{-articulate, the first 2 joints quite short. Anterior
ma\illip.'<U extremely -mall, with the 2nd basal joint scarcely larger than the 1st.
Natatory legs comparatively more slender than in the preceding species. Last
pair of h-i:> very largely developed and quite smooth below, marginal spines much
elongated, setiform, some of them extending as far as the tip of the caudal rami;
di>tal joint oblong oval in form, and regularly trilobate at the end, appendicular
brittle unusually prolonged and issuing from the lower face of the proximal joint;
inner expansion of the latter extending about to the middle of the distal joint,
outer apical spine rather elongated, though somewhat shorter than the inner.

lour whitish gray.

Length of adult female 0.70 mm.

/// iiirlcx. This form, which I cannot identify with any of the species
described by Mr. Scott, is easily recognizable by the acutely produced rostral
plate, and the large size of the Jast pair of legs, the marginal spines of which
are more elongated than in any other form known to me.

Occurrence. Only 2 specimens of this form, both adult females, were
found, together with the preceding species at Selven, Trondhjem Kjord.

28. Pseudobradya similis (Scott).

(PL \\lll. fig. 2).

/;/./,///,/ nmtfw, Th. & A. Sr.,tt, Revision, ].. -liM. PI. 35, fi^a. 3, 7, 16, 27, 33, 41, 48, PL 36,

figs. 3, 10.

Specific ('li<ir<i<-tn:<. /'\-iini/c. Body moderately slender, with highly chiti-

ni/.ed integuments. Cephalic segment, seen dorsally, evenly contracted in front,
tral plate -omewliat deilex.-d and obtuse at the tip. Urosome less massive
than in /'. ocuta, >li.L f litly tapering distally. Caudal rami remarkably large and
elongated. equalling in length the last 2 segments combined ; apical setae compara-
tively short. Anterior antenna- resembling in structure those in /'. acuta. Last
pair of leL's comparatively, large, though somewhat less broad than in /'. acuta,
and clothed on the lower face with several transverse rows of delicate spinules,
marginal Spin 68 of moderate length and somewhat unequal; distal joint oblong

43

oval in form, unequally trilobate at the end, the outermost lobe occurring far in
front of the innermost one; appendicular bristle very strong, spiniform, and, as
in P. acuta, issuing from the lower face of the proximal joint; inner expansion
of the latter rather narrow, and extending somewhat beyond the middle of the
distal joint, outer apical spine very small.

Colour yellowish brown.

Length of adult female 0.59 mm.

Remarlfs. This form, the identity of which with Brady a similis of Scott
I cannot doubt, may be easily distinguished from any of the 2 preceding species
by the remarkably prolonged caudal rami, in which respect it agrees with 2 other
species described by Mr. Scott, viz., P. elegans and P. hirsuta. It is, however,
of much smaller size than either of these species.

Occurrence. Only 2 specimens of this form were found last summer,
together with the 2 preceding species at Selven, Trondhjem Fjord.

Distribution. Firth of Forth (Scott).

Gen. 11. MiCFOSetella, Brady & Robertson, 1873.

Generic Characters. Body very slender, with the anterior division scarcely
broader than the posterior. Cephalic segment projecting in front in a short, de-
flexed rostrum. Epimeral plates of this and the 3 succeeding segments well
developed, partly including between them the oral appendages and the basal parts
of the natatory legs. Caudal rami short, with the 2 middle apical setae greatly
elongated. Anterior antennae slender and elongated, with only scattered bristles;
those in male distinctly geniculate, terminal part rather prolonged. Posterior
antennse with the outer ramus much shorter and narrower than the inner, 3-arti-
culate. Anterior lip not produced in front. Mandibles with the palp very large,
distal joint spatulate in form and about the size of the proximal one, carrying
at the lower edge a remarkably strong spiniform seta, clothed along one of the
edges with long cilia; outer ramus very small. Maxillae of more simple structure
than in Ectinosoma, the palp apparently consisting of only 2 setiferous lobes.
Anterior maxillipeds comparatively small, resembling in structure those in Ectino-
soma. Posterior maxillipeds, however, more strongly built, with the middle joint
rather expanded. Natatory legs with the rami slender and narrow. Last pair
of legs built, on the whole, upon the same type as in Ectinosoma,

44

Remarks.- This genus was established in the year 1873 by Messrs. Brady
& K'..bertson to comprise a small Harpacticoid, M. utlnntim B. & R., taken by
them in the open sea by the aid of the surface-net. The genus was subsequently
withdrawn by Prof. Brady, who in his Monograph described it as Kcthitixtmiii
.itl,intin<m. believing that the anatomical differences were not sufficient to remove
it from that genus. I'r. (ii.-sbrecht has, however, again restored the original
genus, adding another nearly-related form. M. ro*-a (Dana). I am also myself
of ..pinion that the genus M',,-r<i*<'trlln ought to be maintained, differing, as it does,
fmiii />/, '. not only in the peculiar habits of the species, but also in some

anatomical details mentioned in the above diagnosis. Of the 2 hitherto known
species, only one belongs to the fauna of Norway.

29. Mierosetella norvegica (Boeck).

(PI. XXIV).

,><>i-i-i't/i<-fi. Hot-ek. Ovf>rsit over de ved Norges Kyster iagttagne Copepoder. Chr. Vid.

Selsk. Forh. 1864, p. 281.

SVM: Ectinosoma attanticum, Brady.

Specific Characters Female. Body extremely slender, nearly linear in
tiirm. the greatest width scarcely exceeding '/H of the length. Cephalic segment

*

only very -lightly vaulted above, seen dorsally, gradually contracted in front,
rostrum short and abruptly deHexed. Urosome about half the length of the an-
ti-iior division of the body, segments clothed with several circlets of delicate
-pinnies. Caudal ranii scarcely longer than they are broad, apical setae more or
less divergent, the innermost but one about twice the length of the urosome.
\nterior antennae exceeding half the length of the cephalic segment, and composed
of 'i articulations, terminal part fully as long as the proximal one. Last pair of
legs \\ith the distal joint scarcely as long as the proximal one, and rounded in
form, innermost apical spine very small, the other 2 considerably elongated,
setiform. appendicular bristle normal; inner expansion of proximal joint large,
extending as far as the distal joint, inner apical spine much shorter than the outer.

Mnl<- somewhat smaller than female, and easily recognizable by the geni-
culate anterior antenme and the bipartite genital segment.

Body pellucid, white, with a faint yellowish tinge.

Length of adult female 0.46 mm., of male 0.38 mm.

/A ///'///>. - There cannot, in my opinion, be any doubt that the form briefly
recorded by Boeck as Nr/ //a nnn-cij'iL-a is this species, and therefore, according

45

to the rules of priority, the specific name proposed by Boeck ought to be preferred
to that subsequently given to this form by Messrs. Brady and Robertson. It
differs from the 2nd species, M. rosea, in its much inferior size, and in the less
elongated caudal setae.

Occurrence. Unlike what is generally the case with the Harpacticoida,
this form is a true pelagic animal, scarcely ever to be found at the bottom. [
have observed it in several places off the Norwegian coast, and always near the
surface of the sea and generally at a considerable distance from the shore. In
some plankton-samples examined by me, it occurred in great abundance.

Distribution. British Isles, Atlantic Ocean, widely distributed. Arctic
Ocean, Mediterranean, Pacific, Red Sea, Indian Ocean.

Gen. 12. Bradya, Boeck, 1872.

Generic Characters. General form of body not unlike that of Ectinosoma,
anterior division, however, somewhat broader and slightly depressed. Rostral plate
comparatively short and blunt at the tip. Urosome conspicuously narrower than
the anterior division of the body; caudal rami not much elongated, and wide
apart. Anterior antennae short and stout, densely setiferous, and composed of
6 or 7 articulations. Posterior antennas with the outer ramus more fully developed
than in the other genera of this family, being scarcely shorter than the inner,
subfusiform, and distinctly 3-articulate. Anterior lip not produced in front. Man-
dibles with the cutting edge divided into numerous teeth, palp rather large, with
the outer ramus more fully developed than in the other genera. Maxillae normally
developed, the palp having outside 2 setiferous lamellae. Anterior maxillipeds
rather powerful, with the 2 basal joints bent at nearly a right angle, terminal
part short, but distinctly 3-articulate, and clothed with several short setae, one of
which is much stronger than the others and claw-shaped. Posterior maxillipeds
likewise rather fully developed, 1st joint carrying at the end inside a strong de-
flexed seta, and another smaller one at the outer corner, middle joint lamellarly
expanded and provided with an oblique row of delicate spinules, last joint im-
perfectly defined at the base, and carrying 4 ciliated setae. Natatory legs with
the rami comparatively broad. Last pair of legs poorly developed, with the distal
joint rather small or wholly absent.

46

Remarks. In the restriction here adopted, this genus is chiefly charac-

-I h\ tlir Mimewhat dilated and depressed anterior division of the body, the

rather full de\elopmeiit of the -uter rainus of the posterior antenna?, and partly

als,,. hv tin- structure of tin- ~2 pairs of maxillipeds and the last pair of legs.

T\\. \\.-ll-il-tiiied species of this -eiius .n-ur off the Norwegian coast.

30. Brady a typiea, Boeck.
(PI. \\v).

/. ././//<; //// . Boeck, NV Blaegter og AM.T af Salt vamlsmpepocler. Chr. Vicl. Selsk.

IsTi'. p. 47.

>m,-,ic\> rs. - /'< male. Anterior division of body moderately dilated,
-t \\iilth scarcely attaining half the length; rostral plate slightly deflexed
and narrowly rounded at the tip. E))iincral plates projecting behind in an acute
corner. I'm-miir exceeding half the length of the anterior division, last segment
ileeply cleft. Caudal ranii a little longer than they are broad, and considerably
divergent, apical seta3 of moderate length. Anterior antenna? short and thick,
con.->i>tiiiL, r of 7 \voll-derined articulations, the penultimate one with a remarkably
-tnuiLr seta in tmnt. last joint very small, nodiform. Anterior maxillipeds with
the 2nd basal joint smaller than the 1st, unguifonn spine not very strong. Last
pair uf leL'^ rather distant the one from the other, marginal spines very unequal,
some of them rather slender, setiform; distal joint well defined, though compara-
tively Muall. Bubquadr angular, with the outermost apical spine much smaller than
the other j. appendicular bristle slendei- and elongated; inner expansion of proximal
joint with -2 unequal spine> at the tip.

( 'nln /if whitish ^ra\ .

L-'ii-th of adult female 0.90 mm.

Remarks. This form was lirst recorded by Boeck. and subsequently de-
ilied and figured b\ Prof. Brady in his well-known Monograph. It is easily
i ' -ni/ahle from any of the other species referred hy Mr. Scott to this genus,
both by the outer li.ilutu-, and by some of the anatomical details.

^""" I have met with th^ form in several places on the Norwe-

gian coast From the Christiania Fjord to Trondhjem Fjord. Mr. Th. Scott records
i' ;I|MI 1'rom Kinmaik. It occurs in depths ranging from 10 to 30 fathoms,
muddy In, tinm.

Distribution. British Uh-s (Brady, Scott).

47

31. Brady a dilatata, G. 0. Sars. n. sp.

(PI. XXVI).

Specific Characters. Female. Anterior division of body considerably
dilated, seen dorsally, broadly oval in form, with the greatest width exceeding
half the length. Rostral plate well developed, narrowly rounded at the tip.
Urosome scarcely more than half as long as the anterior division of the body,
and much narrower. Caudal rami about as in B. typica. Anterior antennae com-
posed of only 6 articulations, the last 2 being confluent. Posterior antenna?,
mandibles, maxillae, and posterior maxillipeds, of much the same structure as in
B. typica. Anterior maxillipeds, however, considerably more powerful, with the 2nd
basal joint fully as large as the 1st, and the apical claw remarkably strong.
Natatory legs rather short, with unusually broad, flattened rami. Last pair of
legs very small and imperfectly developed, each forming a simple setiferous lam-
ella, without any trace of subdivision.

Colour whitish gray.

Length of adult female 1.20 mm.

Remarks. This form, though closely agreeing with B. typica in most of
the structural details, may be at once distinguished by the much broader form of
the anterior division of the body, the very powerfully developed anterior maxil-
lipeds, and the peculiar rudimentary condition of the last pair of legs. It also
grows to a considerably larger size.

Occurrence. Only 2 female specimens of this form have hitherto come
under my notice. They were taken many years ago in the upper part of the
Christiania Fjord, in a depth of about 30 fathoms.

Section II. Chirognatha.

Remarks. As stated above, the forms belonging to this section are chiefly
characterised by the structure of the posterior maxillipeds, which, unlike those
in the preceding section, constitute more or less powerful prehensile organs,
terminating in a clawed hand. Of the 2 subsections into which it is divided, that
of the Dactylopoda is by far the most extensive, and I propose to treat of this
subsection in the first place.

48

Subsection i. Dactylopoda.

Character, Kir-t pair of legs unlike the others, and more or less

distilirth prehensile.

Fam. 5. Harpacticidae.

Cli<ii-iirl, /-. I'x-dy of various form, in some cases slender .and compressed
sub-depress, -d. in other cases much abbreviated and flattened. Rostrum well
defined at the base, and to some extent mobile. Eye present. Anterior antennae
:nparati\el\ -lender, with the proximal part consisting of 4 well-defined joints,
terminal part of 4 >r r> mneh smaller articulations; those in male strongly pre-
hensile, terminating in a clawed hand. Posterior antennae rather powerful, biarti-
culate. distal joint inure or less spatulate, and armed at the tip with 3 strong,
daw-like spine-, and behind them with \ geniculated setre, outer ramus comparatively
small, and issuing from the middle of the proximal joint. Mandibles highly in-
crustateil. with short and blunt cutting teeth, palp of moderate size, with 2 slender
n\ed rami. .Maxillie normal. Anterior maxillipeds short and stout, with
ral digitifnrm lobes in front, the outermost one carrying an unguiform spine.
l'u-terir maxilliped- more or less powerfully developed, subcheliform. First pair
nf h-^s with both rami distinctly prehensile and very unequal, the outer one being
much the longer, and armed at the tip with a number of curved claws, the inner
one with a single such claw. Natatory legs with both rami 3-articulate, the outer
niie hein^ the larger. Last pair of legs lamellar, biarticulate, proximal joint in
female mure or less expanded inside. Ovisac single.

"Remarks. In the restriction here adopted, this family is chiefly charac-
teri-ed h\ the structure of the 1st pair of legs, the rami of which are very unequal
in leiiL'th and both prehensile. It comprises at present 3 genera, all of which
are represented in the fauna of Norway.

49

Gen. 13. HarpaCtlCUS, M.-Edwards, 1838.

Syn: Arpacticus, Baird.

Generic Characters. Body slender, compressed, or slightly depressed,
tapering behind. Urosome normal, with none of the segments expanded laterally,
and considerably narrower in male than in female. Caudal rami short, more or
less divergent, one of the apical setoe considerably elongated. Rostrum conically
produced, and more or less curved downwards. Anterior antennae in female 8- or
9-articulate; those in male very strong, with the 1st joint divided into 2 articu-
lations, last joint of the proximal part globularly expanded, terminal part very
movable, claw-shaped. Posterior antennae with the apical spines simple, outer
ramus composed of only 2 joints. Posterior maxillipeds generally very powerful,
with the hand considerably expanded. First pair of legs with the outer ramus
biarticulate, and nearly twice as long as the inner, apical claws but slightly
curved. Inner ramus of 2nd pair of legs in male with the middle joint produced
at the end outside to a long deflexed mucroniform projection; 3rd pair of same
with the outer ramus exceedingly strong, curving more or less inwards, and having
the spines very coarse, whereas the natatory seta? are rudimentary. Last pair of
legs of moderate size, with the marginal spines, as a rule, not much prolonged,
distal joint oval, inner expansion of proximal joint in female comparatively broad,
in male rudimentary.

Remarks. This genus was established as early as the year 1838 by
M.-Edwards, to include the Cyclops chelifer of 0. Fr. Miiller. Several additional
species have subsequently been described by different authors ; but some of these
species are now generally referred to other genera, or even to quite different
families. One of the most characteristic features by which the present genus
is distinguished from the 2 other genera of this family, is the peculiar trans-
formation in the male of the outer ramus of the 3rd pair of legs, which constitutes
a most powerful prehensile organ, by the aid of which, apparently, the female is
grasped during copulation. To the fauna of Norway belong 4 distinct species, to
be described below.

32. Harpaeticus chelifer (Muller).

(PI. XXVII & XXVIII).
Cyclops chelifer, 0. Fr. Miiller, Entomostraca, p. 114, PL XIX, figs. 1 3.

Specific Characters. Female. Body pronouncedly compressed, especially
in its anterior part, seen dorsally, very narrow, with the greatest width quite in

7 Crustacea.

50

front, and gradually tapering behind. Cephalic segment rather large and deep,
with the rostrum very prominent. Epimeral plates of the 3 succeeding seg-
ments rounded at the lateral corners. Last pedigerous segment comparatively
small. Urosome not attaining half the length of the anterior division, posterior
edges of the segment finely spinulose. Caudal rami about as long as they are
broad, and somewhat divergent, apical setae rather slender, the innermost but one
about twice the length of the urosome. Anterior antennae comparatively slender
.^-articulate, terminal part not attaining ' :i of the length of the antenna. Posterior
ant. -nn;e very greatly developed, outer ramus, however, small, with 6 setae. Pos-
terior maxillipeds exceedingly large and powerful, hand nearly globose in form,
with the palm somewhat hollowed, its upper angle coarsely denticulate, dactylus
\.TV ^trong and curved. First pair of legs rather strongly built, joints of the
outer ramus of about equal length, the distal one armed at the tip with 3 finely
denticulated claws; inner ramus 3-articulate, the outer 2 joints very small and
imperfectly defined, apical claw of same appearance as those of the outer ramus.
Natatory legs with the outer ramus much stronger than the inner, 1st joint the
largest, terminal joint rather narrow, with 4 coarse spines outside gradually in-
creasing in length distally. Last pair of legs with the inner expansion of the
proximal joint moderately broad, and provided with only 3 marginal spines.
Ovisac generally not very large, oval in form.

.I/"/' somewhat larger than female, with the urosome narrower. Anterior
antennae very powerful, hand strongly dilated, dactylus simple. Outer ramus of
3rd pair of legs exceedingly large and robust, with the 1st joint fully as long as
the other 2 combined, last joint spatulate, armed with 3 very thick spines. Last
pair of legs much smaller than in female, distal joint oblong quadrangular in
form, proximal one not at all expanded inside.

( 'nli ,n r light yellow.

Length of adult female 0.90 mm., of male about 1 mm.

/// marks. -The above-described form is unquestionably that originally
recorded by ( >. Kr. Miiller as Cyi-fuji* clu-lifcr. In some cases, however, quite
different forms have been identified with Miiller's species. Prof. Brady has ap-
parently confounded this species with H. grodlis of Glaus, and some of the figures
given in his Monograph seem indeed to be more properly referable to that form.
<>n a closer examination, the present species may be easily recognized by the
pronouncedly compressed form of the body, and by the unusually large posterior
maxillipeds. Moreover, both in the structure of the antenn;e and of the legs,
well-marked ditl'erences from the other species are found to exist.

Occurrence. This is one of the commonest of our Harpacticoids, being

51

found rather abundantly along the whole Norwegian coast, from the Christiania
Fjord to Vadso. It is a true littoral form, occurring in quite shallow water close
to the shore, among algae, and not infrequently left in tidal pools together with
other littoral species. It moves in a somewhat jerky manner; but it is more
frequently found clinging to the algae or other submarine objects. The two sexes
are often found tied together in copula, the male having a firm hold of the female
by the aid of his powerful clawed anterior antennae, which are inserted within
the hind edge of the cephalic segment of the female.

Distribution. British Isles (Brady), Heligoland (Glaus), coast of Bohuslan
(Coll. Cleve), coast of France (Canu), Arctic Ocean (Scott), coast of North America,
Ceylon (A. Scott).

33. Harpaeticus uniremis, Kroyer.

(PI. XXIX).
Harpaeticus uniremis, Kroyer, in Gaimard's Voyage en Scandinavie, PL 43, fig. 1, a p.

Syn : Harpaeticus nordlandicus, Boeck.
chelifer, var. arctica, Poppe.

Specific- Characters. Female. Body moderately slender, subdepressed,
with the greatest width equalling about y 3 of the length, and occurring a little
in front of the middle. Cephalic segment rather large, but less deep than in
H. chelifer, rostrum broader and more obtuse at the tip. Epimeral plates of the
3 succeeding segments somewhat expanded laterally, and acutely produced at the
lateral corners. Last segment of metasome rather broad. Urosome gradually
somewhat coarctated behind, with the hind edges of the segments coarsely spinulose
ventrally. Caudal rami very short, scarcely as long as they are broad, apical
setae slender, the innermost but one more than twice as long as the urosome.
Anterior antennae moderately slender, 9-articulate, terminal part considerably
exceeding half the length of the proximal one. Posterior antennae about as in
H. chelifer. Posterior maxillipeds rather strongly built, though not nearly so
powerful as in that species, hand rounded oval in form. First pair of legs re-
sembling in structure those in H. chelifer, but with a greater number of claws
at the tip of the outer ramus. Last pair of legs with the inner expansion of the
proximal joint very large and broad, carrying 4 marginal spines, distal joint
comparatively smaller.

Male, as usual, somewhat larger than female, with the urosome narrower
and distinctly 5-articulate. Anterior antennae with the dactylus securiform in
shape, projecting outside in a strong spiniform process. Outer ramus of 3rd pair
of legs somewhat less powerfully developed than in H. chdifer, 1st joint shorter

52

than the other 2 combined, last joint armed with 4 spines, the innermost rather
slender. Last pair of legs very small.

Colour gray, with a slight yellowish green tinge.

Length of adult female 1.23 mm., of male 1.33 mm.

/,', ,,M /,/>>. --This form was figured, but not described, by Kroyer in the
Atlas to Qaimard's well-known work "Voyage en Scandinavie". It is much the
largest of our Harpactici. and is moreover easily recognizable by its comparatively
broad, sub-depressed body. The I/<tr/><irt/<;is n<>nlltnnl'irn* of Boeck is unquestio-
nably identical with this species; and the form recorded by Mr. S. A. Poppe as
//<////'/>//'//> flu /i/'ir. var. arrticd, is also referable to the same species.

Occurrence. I have met with this form rather frequently along the whole
Norwegian coast, from the Christiania Fjord to Vadso. It is not, however, like
the preceding species, a littoral form, but is only found in depths ranging from
20 to 100 fathoms, muddy bottom.

Distribution. Behring Sea (Poppe), Bear Islands, Spitsbergen (Scott).

34. Harpacticus graeilis, Glaus.

(PI. XXX, fig. 1).
H<n inn-Hi ax 1/rin'iljs. Clans. Dir (Veilebenden Copepoden. p. 1H5, PI. XIX, tig. iJO.

s\n: Harpacticus elongatus : Boeck.
chelifw, Giesbrecht (not Muller).

r*. FeiiKilr. Body rather slender, with the anterior
division slightly depressed, the posterior considerably narrower. Rostrum rather
prominent. Caudal rami very short, not nearly as long as they are broad, apical

i- slender and divergent. Anterior antennae rather elongated, attaining the
length of the cephalic segment, 9-articulate, terminal part scarcely exceeding in
h'liLrth of the proximal part. Posterior antennae with the outer ramus normal.
Posterior maxillipeds resembling in shape those in H. /n/n-niii*. First pair of
l<\L f s c'.in|iarativelv more slender than in the 2 preceding species, with the distal
joint of the outer ramus shorter than the proximal one; inner ramus with the
outer 2 joints confluent. Last pair of legs with the distal joint oblong in form;
inner expansion of proximal joint well developed, though less broad than in H.
HHII-I mi*, marginal spines of both joints rather slender, setiform.

Mali exhibiting the usual differences from the female. Outer ramus of

I pair of legs considerably incurved, last joint with 3 thickish spines and a
long ciliated seta at the inner corner. Last pair of legs very small, with the
distal joint somewhat club-shaped, the 2 outermost setae spiniform.

53

Colour whitish, with a slight yellowish tinge, and generally banded dors-
ally with dark brown.

Length of adult female 0.66 mm.

Remarks. I cannot doubt that the above-described form is that originally
recorded by Glaus as H. gracilis. The H. elongatus of Boeck is the same species,
and this is unquestionably also the case with the form described by Dr. Gies-
brecht as H. chelifer, Miiller. Prof. Brady seems to have been acquainted with
both these forms; but he only regarded H. gracilis as a variety of H. chelifer,
though in reality it is very distinct both in the external form and in the structure
of some of the appendages.

Occurrence. I have found this form occasionally in several places of the
Norwegian coast, as far as to the Trondhjem Fjord. It is, like H. chelifer, a
littoral form, occurring in comparatively shallow water among algae.

Distribution. British Isles (Brady), Kiel Bay (Giesbrecht), Mediterranean
at Messina (Glaus).

35. Harpacticus flexus, Brady.

(PJ. XXX, fig. 2).

Harpacticus flexus, Brady & Kobertson, Ann. Mag. Nat. Hist. ser. 4, Vol. XII, p. 134, PI. IX,

figs. 1721.

Specific Characters. Female. Form of body resembling that in H. gracilis,
though perhaps still more slender. Rostrum less prominent. Caudal rami
broader than they are long. Anterior antenme unusually short, being scarcely
half as long as the cephalic segment, 9-articulate 7 terminal part about half the
length of the proximal one. Posterior antennae with the outer ramus very narrow
and provided with only 3 setae. Posterior maxillipeds rather unlike those in the
3 preceding species, the hand being narrow fusiform and the dactylus very slender.
First pair of legs of much the same structure as in H. gracilis. Last pair of legs
likewise rather similnr, but with the distal joint comparatively smaller, and the
marginal spines shorter, scarcely setiform.

Colour rather peculiar, the greater part of the anterior division being
tinged with deep crimson, cephalic segment and urosome white.

Length of adult female 0.70 mm.

Remarks. This form, first described by Messrs. Brady & Robertson, may
be easily distinguished from the other species of the present genus by the shortness
of the anterior antennae and the rather different shape of the posterior maxillipeds.
In the living state it is moreover readily recognized by its peculiar and beautiful
colouring.

"' '

,'. Only some few specimens of this form have hitherto come
under inv notice. They were taken, some in the upper part of the Christiania
Fjord. ami some "tV the west coasl of Norway in comparatively shallow water

Distribution. British Isles (Brady).

Gen. 14. TigTiOpUS, Xonnan. 1868.

Genet I < 'li",-a<-l> /-x. General form of body resembling that in Hnriiti<-firit*.
though comparatively more attenuated behind. Anterior antennae more robust, in
male \er\ -tn>ng. siibchelate. Posterior antennae with the outer ranius composed
of 4 di-tinctlx-detiiied articulations. Oral parts on the whole resembling in structure
those in //<ii-iirtii-*. First pair of legs, however, with the outer rainus distinctly
rticulate. last joint small but well defined, and armed at the tip with a number
of sharply curved claws. Inner ramus of 2nd pair of legs in male with the middle
joint produced at the end both outside and inside in a deHexed spine; outer
ramus of :'jrd pair of exactly the same appearance in the 2 sexes. Last pair of
h-i:- of a structure similar to that in /I<n-j>arti<-ns, but with the marginal spines
\ery -lender, setiform.

/'/ murks. This genus, proposed in the year 1868 by Norman, is closely
related to //iii'iinrticiis, and was not, indeed, accepted by Prof. Brady in his
.Monograph. Yet it seems to me that the genus ought to be maintained, on ac-
count of -omc \\ell-marked diti'erences to be found in the structural details in both
sexi The L'eim-, i ontains as yet only a single species, to be described below.

3<). TigriopUS fulvus (Fischer).

(I'l. XXXI ^ XXXII i
HarpacticUS /ulrn-,. S.-l,. l-'i-i-lnT. I'.i-iir-iL:'' /.ur Kenutnls- dcr l-'.ni nmust rakcu. Alili. d. Ki'mi^.

Bayer. Aka.i.. Vol. VIII. () . (;r.ti, I'l. I, figs. :{< :i:i: I'l. II. li.irs. :;i :$!>.

S\n- HIII-IIHI-HCHN <-hfli/'r>-. Lilljfliitrtf (not
< iii-tiron/is. i;..r.-U.

CrdBsiCOrniSj l?rad\ \

Tiiji-iujiiiK l.illjrln-yji.

ifit Characters. l-\i/uilc. Anterior division of body much broader
than the posterior and, seen dorsally, oblong oval in form. Rostrum comparatively

55

short and blunt at the tip. Urosome rather narrow, almost linear in form, with
the segments finely spinulose at the hind edges. Caudal rami somewhat longer
than they are broad, apical setse rather slender, the innermost but one more than
twice as long as the urosome. Anterior antennae somewhat exceeding half the
length of the cephalic segment, 9-articulate, the proximal joints comparatively
thick and robust, terminal part rather slender. Outer ramus of posterior antennae
with the 1st joint longer than the other 3 combined. Anterior maxillipeds com-
paratively broad; posterior ones with the hand oblong quadrangular in form, palm
not defined, dactylus strong and curved. First pair of legs rather strongly built,
outer ramus with the 1st joint about the length of the other 2 combined; last
joint armed with 5 very sharp and smooth claws and 2 setse; inner ramus with
the outer 2 joints imperfectly defined, and carrying on the tip a strong claw-like
spine. Last pair of legs with the inner expansion of the proximal joint very large,
extending somewhat beyond the distal joint, and armed with 5 slender spines, one
of which is very long; distal joint oval in form, with 5 similar spines. Ovisac
very large.

Male about the same size as the female, but having the posterior division
of the body considerably narrower. Anterior antenna? very strong, hand nearly
globose, dactylus simple, claw-shaped. Inner ramus of 2nd pair of legs with the
middle joint considerably expanded, outer projection smooth, inner somewhat
longer, and densely hairy in its outer part. Last pair of legs very small, prox-
imal joint but very slightly expanded inside, and provided with a solitary seta,
distal joint oval, with 4 spiniform setae.

Colour dark yellow or orange.

Length of adult female 1.20 mm.

Remarks. This form was first described by Prof. Lilljeborg, who, how-
ever, erroneously identified it with Cyclops chelifer of 0. Fr. Miiller. It was
some years afterwards recorded by Seb. Fischer as Harpacticus full-its, and the
specific name proposed by that author ought accordingly to be retained and pre-
ferred to those given to the species by Boeck and Norman, which are of
later date.

Occurrence. This form is found along the whole Norwegian coast, and
often in great abundance, in small rock-pools at, or more generally somewhat
above, high-water-mark. The water in these pools is more or less brackish and
often exhibits a very high temperature by long exposure to the sun. I have also
occasionally found this form in perfectly fresh water, but in no cases at any great
distance from the shore, and it is reasonable, therefore, to assume that at times

_56

i, places, hy hea\y storms or excessively high tides, are exposed to some .ad-
mixture ! salt \\ater.

/i,.ti-ilmti"n. British Isles (Brady), coasts of Sweden (Lilljeborg), France
IU), Madeira ( Kischeri. Kernm-h-n Mauds (Brady).

Cm. 15. ZaUS, Goodsir, 1845.

Generic Characters. Pody short and broad, flattened, with the segments
of tin- anterior division lainellarly expanded laterally. Rostral plate broad, sub-
trnncate at the tip. Lust pedigerous segment very small, without any distinct
epimeral plates. I'rosome narrower than the anterior division, though having the
anterior segments somewhat expanded laterally; genital segment in female with
distinct traces ot' a subdivision. Caudal rami short, with the normal number of

e. Anterior antenna- in female 9-articulate, terminal part comparatively short;
those in male strongly prehensile. Posterior antennae well developed, with the
-pines of the terminal joint in most cases densely fringed with cilia on the one
due; outer ranuis comparatively small, Inarticulate. Oral parts on the whole
re-. -milling in structure those in I/ariHtrfintx: posterior maxillipeds, however,
comparatively smaller. First pair of legs, as in Htiri>tirt'-nx. with both rami
distinctly prehensile and of very unequal length, the outer one being much the
longer and biartieulate, tipped by a number of strong claws. The 3 succeeding
pairs rathei- --lender, and of exactly same structure in the two sexes. Last pair

of le^s i e or less extended laterally, distal joint comparatively large, inner

expansion of proximal joint in female very broad, though not much prominent,
in male rudimentary. <>\isa<- broad, flattened.

/,'< inn,/,-. -This -einis, established as early as the year 1845 by Goodsir,
has h\ most ant hoi's been referred to the family I'dli/lmlir, on account of the
broad flattened body. The several appendages, however, are built upon the very
same t\pe as in the ^r-nus /l<ti-j>ir/<-n*, and the present genus ought therefore
more properly to be included in the family //or/xii-lii-iiltc as here defined. It may
be noted hen-, that one of the characters assigned to this genus by Prof. Brady,
"head distinct from cephalothorax" does not hold stand. The head is in
n-alit\. a- in most other I larpacticoids, wholly united with the 1st pedigerous

fluent; nor is the outer minus of the 1st pair of legs, as indicated by that
author, .''.-articulate, but like that in Hiifjinrt/r/i*. only composed of 2 joints.

Copepoda

Ectinosomidas Harpaciicoida

PLXVH

6.0. Sars

^ Fctinosoma neglectum, G.O.Sars

propinqvum, Scott.

Copepoda

Ectinosomidae Harpacticoida

P1.XVBT

Sars autonr.

.- , r\ n O

1 Ectmosoma elongatum, G. 0. Sars

2 " Herdmani Scott

Trykti den private Opmaalinq.CTira

Copepoda

Ectinosomidae Harpacticoida

PLXK

:

m

s.o. S.TS

1 Ectinosoma melamceps, Boeck

Normani, Scott.

Ectinosomidae

Copepoda

Harpacticoida

P1XX

curficorne, Boeck Tryk " denpnVlrte0pmaalm9 ' Chra
gothiceps, Giesbrecht

Copepoda

Ectinosomidae Harpacticoida

pixxr

vj ,*4 N

G Sars autogr.

1 Ectinosoma mixtum, G.O.Sars

Trykl i den private Opmaalmg.Chra

brevi rostre, G 0. Sars

Ectinosomidae

Copepoda

Harpacticoida

P1.XXE

/<V '

+. ,11

- Owf

'<";~iyr<irt<

G.O. Sars autogr.

i_ . . . . _ Trvkl i den private Opmaalinq.Chra

1 Ectmosoma gracile, Scott.

2 Pseudobradya minor (Scott.)

Ectinosomidae

Copepoda

Harpacticoida

Rxxnr

v

ST! 10 j i i r\ f. n Trvkhden onvate Opmaalmg.Chra

Pseudobradya acuta, G.O.Sars

similis (Scott)

Ectinosomidae

Copepoda

Harpacticoida

Pixav

G SaTS aut03IV Microsetella atlantica ; Brady

Trykt i den private Opmaaling.Chra

Ectinosomidae

Copepoda

Harpacticoida

PI .XXV

"

\

',

II \ M

*

G Sars autogr.

Bradya typica, Boeck.

Norsk I i;h Offici.i Kr a

-Ectinosomidae

Copepoda

Harpacticoida

PLXXVI

v

." $4

: ;\ '

LJEUui

G.O Sars autogr.

Bradya dilatata, G.O. Sars

Norsk li!h.0fficn Kr?

HarpacTicidae

Copepoda

Harpacticoida

PI. XXVII

' * :

C.O Sars autogr. Norsk li:h Official Kr

Harpacticus chelifer, (Muller).

Harpacticidae

Copepoda

Harpacticoida

P1.XXV1II

G.O Sars autogr.

Harpacticus chelifer, (Mullen).
( continued .)

Norsk lith-Offici.i Kr?

Harpacticidae

Copepoda

Harpacticoida

PL

. i *

/

GO Sars autogr.

KorsklilhOfficm Kr?

Harpacticus uniremis,Krdyer .

Harpacticidae

Copepoda

Harpacticoida

P1.XXX

-:V

4

-

G.O.Sars autogr.

1 Harpacticus gracilis, Glaus.

2 flexus, Brady.

Norsk lith.Officin Kr?

Harpacticidae

Copepoda

Harpacticoida

P1.XXXI

w

4

GO Sars autogr

Tigriopusfulvus, Fischer.

Norsk li'.hOffiri.i Kr?

Harpacticidee

Copepoda

Harpacticoida

PI. XXXII

".<

Pi mi

'. ',' '.'.
:

n -'

.

t '"'"I <nr,KMI<l ""'"'

G.O.Sars autogr.

Tigriopus fu I vus, Fischer.

( continued ;

Norsk lithOfficin Kr a

AN ACCOUNT

OF THE

CRUSTACEA

OP

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS V & VI

HARPACTICID^] (concluded), PELTIDIID^, TEGASTHXE, FOR-

CELLIDHDJE, IDYIDJE (part)

WITH 16 AUTOGRAPHIC PLATES

BERGEN
PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMERMEYER'S FORLAG, CHRISTLANIA

.1904

Three distinct species of this genus belong to the fauna of Norway. Mr.
Poppe has moreover described a 4th species from the Behring Sea as Z. Anrdii,
and another species is recorded by Prof. Brady from the Kerguelen Islands, but
it is erroneously identified by him with one of the northern species (Z. j>innlnx).

35. Zaus spinatus, Goodsir.

(PI. XXXI).

Zaus spinatus, Goodsir, On several new Species of Crustaceans allied to Saphirina. Ann. Mag.

Nat. Hist. Vol. XVI, pag. 326, PL XI, figs. 18.

Syn: Zaus spinosus, Glaus.

Specific Characters. Female. Anterior division of body, seen dorsally,
oval in outline, though scarcely attenuated behind. Cephalic segment narrowly
rounded in front, rostrum slightly prominent, obtuse at the tip. Last pedigerous
segment very small and becoming suddenly much narrower than the others.
Urosome about half the length of the anterior division, genital segment rather
broad, with the lateral parts expanded, and finely setiferous at the edges; the 3
succeeding segments rapidly diminishing in size. Caudal rami about as long as
they are broad, and obtusely truncated at the tip, the innermost but one of the
apical seta? rather elongated, exceeding half the length of the body. Anterior
antennae moderately slender, almost attaining the length of the cephalic segment,
terminal part longer than the preceding joint. Posterior antennae with the ter-
minal joint about the length of the basal one, its 3 spines clothed outside with
a dense brush of cilia. Posterior maxillipeds with the hand quadrate in form,
dactylus comparatively short, with a secondary spine at the base inside. First
pair of legs with the distal joint of the outer ramus shorter than the proximal
one, and widening considerably towards the end, apical claws bordered on one
side with a dense comb-like series of cilia; inner ramus exceeding half the length
of the outer and only biarticulate, last joint very small, with a single apical claw of
the same appearance as those on the outer ramus. Natatory legs with the spines
outside the last 2 joints of the outer ramus bordered on one side with a comb-
like series of cilia. Last pair of legs of moderate size, distal joint much smaller
than the proximal one, and broadly oval in form; inner expansion of the latter
rather broad, with the edge evenly convex and densely ciliated between the setae.

Male considerably smaller than female, with the urosome narrower and
distinctly 5-articulate. Anterior antennae very strongly built, 6-articulate, 2nd
joint quite short, - 3rd large, gradually widening distally, penultimate considerably

8 Crustacea.

_

tiunetird. last -mall, daw-like and very mobile. Last pair of legs with the distal
joint of exactly tin- same appearance as in the female, proximal one. however,
much smaller ami not at all expanded.

< ..lour pale yellow, sometimes with a faint rosy tinge.

L'-ngth of adult female 0.56 mm., of male 0.-14 mm.

/,' .mirk*. This form was hrietly described l>y Goodsir as early as the
yi-ar Is)."., and has subsequently been observed l>y several other autliors. The
Arctic form, '/,. Aurelii of Poppe, is very nearly related to this species, scarcely
dillering except in the form of the distal joint of the last pair of legs, which is
comparatively narrower and more produced at the tip.

Occurrence. ] have met with this form not unfre<|iiently along the greater
part of the Norwegian coast, and I am disposed to helieve that the form recorded
hy Th. Scott from Kinmark as '/.. Auriln Poppe, may more properly he referable
to the present species. It is a strictly littoral form, living near the shore among
al^-e. ;md is occasionally left in tidal pools together with other littoral species.
The flattened form of its body makes it very easy for it to run along the fronds
of the alga' or other smooth objects. Male and female are often found tied to-
gether in copula, as figured by Clans.

I >,-.!, i/,,itinn. British Isles (Goodsir), Heligoland (Glaus), coast of France
(<'anu). Arctic Ocean, at Xuvaja Xemlia and Fran/ Josef's Land (Scott).

36. Zaus abbreviates, G. 0. Sars. n. sp.

(I'l. XXXIIi.

Body \ cry Hat, shield-like, rounded oval
in outline, with the segments of the anterior division lamellarly expanded later-
ally. Cephalic segment broadly rounded in front, rostrum broad, lamellar, obtusely
truncated at the tip. Last pedigerous segment very small. I'rosome comparative!}
short and broad, not nearly attaining half the length of the anterior division;
ir> nital segment considerably expanded and densely ciliated at the edges, postero-
lateral corners of tbis ;,nd tbe succeeding se-iueiit conicallv produced. Oaudal
rami about as in '/. >/////'//,/>. Anteriui 1 antenna' with the terminal part ver\ short.
-cMi-cely longer than the preceding joint. Posterior antenna' and oral parts re-
sembling in structure those parts in the preceding species. First pair of legs like-
wise rather sjinjhir, though \\ith the distal joint of the outer ramus comparatively
longer and lc^> dilated to\\;inls the end: inner ramus ai-med at the tip with 2
Bpines, one of which is digitiform and quite smooth. Natatory legs comparatively

59_

more slender than in Z. xpiixthfx, spines outside the last 2 joints of the outer
ramus provided, as in that species, with a dense brush of cilia on one of the
edges. Last pair of legs differing conspicuously in form from those in the other
known species, distal joint rather large and somewhat lozenge-shaped, outer margin
convex, inner straight, apex narrowly produced, both edges densely ciliated;
proximal joint constricted in the middle, with the posterior edge deeply concaved
and quite smooth between the marginal setae, 2 of which, attached close to the
extremity, are considerably elongated.

Body of a light yellow colour, with a dark orange transverse band across
the back, occupying the dorsal parts of the 2 anterior free segments of metasome;
urosome more or less .deeply tinged with the same colour.

Length of adult female 0.62 mm.

R&marTcs. This form may be easily distinguished both from Z. xj>int/ix
and Z. Aurelii by its short, broad, shield-like body, and by the characteristic
form of the last pair of legs. It is very strange that this distinct species, which
most probably also occurs off the Scottish coast, has quite escaped the attention
of that diligent observer, Th. Scott. It has perhaps been confounded by him with
Z. spinatus.

Occurrence. The present species is by no means rare off the west coast
of Norway. It is however never found close to the shore, like Z. sjtittattis. but
seems to be restricted to the region of the red algse, where it often occurs in
considerable numbers.

Distribution. Polar islands north of Grinnell Land (2nd Fram Expediton).

37. ZaUS Goodsiri, Brady.
(Pi. xxxv).

Zaus Goodsiri, Brady, Monograph of British Copepoda, Vol. II, p. 156, PI. LXVf, figs. 1013.

Syn: Zans ovalis, Glaus (uot Goodsir).

Specific Characters. Female. Body oblong in form and much depressed,
with the integuments very much incrusted. Cephalic segment large and broadly
rounded in front, rostrum broad, lamellar. Epimeral plates of the 3 succeeding
segments tongue-shaped, with a nodiform projection at the base anteriorly. Last
segment of metasome comparatively larger than in the 2 preceding species, thougl
much narrower than the other .segments. Urosome equal in length to about
of the anterior division, genital segment rather large and, like the succeeding
segment, produced at the postero-lateral corners to conical projections finely cili-

i

_ G0

ouSide: last segment very small and deeply cleft. Caudal rami nearly
twice as long as they an- broad, and each produced at the tip outside to a
dentiform projection; apical seta 1 unusually short, the innermost but one scarcely
exceeding half the length of the urosome. Anterior antenna' comparatively shorter
ami stouter than in the 2 preceding species. Posterior antenna with the terminal
joint comparatively short and much dilated distally. spines of outer edge pro-
vided with short cilia on the one side. Mandibles, maxilhe and anterior maxil-
lipeds about as in the other species. Posterior maxillipeds, however, considerably
Wronger, with the hand oval in form, and the dactylus very coarse. First pair
of le.L'N rather slender, distal joint of outer ramus scarcely widening at all towards
the end. apical claws with short cilia; inner ramus distinctly 3-artieulate, last 2
joints small, but well defined, apical claws very strong. Natatory legs resembling
in structure those in the 2 preceding species, but with the innner ramus com-
paratively shorter. Last pair of legs very large, distal joint oblong oval in form
and densely hirsute; inner expansion of proximal joint lamellar, transversely
truncated at the tip. which is finely denticulate at the edge, and provided with 4
very unequal setse, the outermost rather small, the next much elongated, the 2
innermost very coarse and spiniform.

Body of a dark yellow colour, with a broad reddish brown transverse
I tarn! across the back, occupying the dorsal parts of the 3 tirst free segments of
metasome.

Length of adult female 1.40 mm.

/iV///"/7>'. I fully agree with Prof. Brady in saying that the identification
by ('laus of this form with N/r/v/y/r ovalis Goodsir, cannot properly be sanctioned;
and the name proposed by Brady is now also generally accepted by other authors.
It is an easily recognizable species, being much larger than any of the others,
ami also differs conspicuously in the more elongated form of body.

Occurrence.- Only a few specimens of this form, all of them females,
have hitherto come under my notice. They were found oil' the west coast of
Norway, in depths varying from 20 to 50 fathoms.

/>isli-ilintinn. P.riti>h [sles (Brady), Heligoland ( ( 'laus). Arctic Ocean we>t
of Spitsbergen (Scott), Polar islands north of (Jrinnell Land (2nd Fram Fxpedition).

61

Fam. 6. Peltidiidae.

Characters. Body short, depressed, with greatly incrusted integuments.
Cephalic segment large, more or less flattened, rostrum immobile, not defined at
the base. Epimeral plates of the 3 succeeding segments, in some cases also of
the last, lamellarly expanded. Urosome short and broad, generally bent down-
wards. Eye present. Anterior antennaB 6 9 articulate, in male slightly trans-
formed. Posterior antenna? distinctly 3-articulate, outer ramus comparatively
small, biarticulate. Mandibles not very strong, palp slender, bi- or uniramous.
Maxillae comparatively small. Anterior maxillipeds with 3 slender setiferous lap-
pets inside, terminal joint incurved and generally armed at the tip with a slender
claw. Posterior maxillipeds terminating in a strongly clawed hand. First pair
of legs with the inner ramus natatory, the outer distinctly prehensile. Natatory
legs with both rami slender, 3-articulate. Last pair of legs of the same appear-
ance in the two sexes, biarticulate, more or less falciform, proximal joint scarcely
expanded. Ovisac single, rounded, extending in front between the bases of the
natatory legs.

Remarks. In the restriction here adopted, this family is chiefly charac-
terised by the short depressed form of body, the short more or less incurved
urosome, the immobile rostrum, and the structure of the 1st and last pais of legs.
In the structure of the posterior antennae and the oral parts, well-marked differ-
ences from the Harpactiddas are also to be found. The family comprises as yet
3 genera, 2 of which are represented in the fauna of Norway.

Gen. 16. Alteutha, Baird, 1845.

Syn: Carillus & Sterope, Goodsir.
Peltidium, Brady (not Philippi).

Generic Characters. Body more or less oval in outline, with the lateral
parts of the cephalic segments inflexed ventrally. Epimeral plates of last segment
of metasome much smaller and more rounded than those of the 3 preceding seg-
ments. Genital segment large and expanded, the succeeding segments of urosome
short and tapering rapidly. Caudal rami short and broad, lamellar, each with a
strong spine on the lower face, apical seta3 comparatively short, 3 of them placed
close together at the inner corner. Anterior antennae of moderate length, 8- or

62

9-articulatc. Mandibular palp distinctly biramous. Maxillae with the palp normally
developed, endopodal part somewhat produced. Anterior maxillipeds with the
terminal joint of moderate length, and tipped with a slender claw. Posterior
maxillipeds with the basal part uni- or Inarticulate. First pair of legs 'with both
rami 3-articulate, terminal joint of outer ramus armed with several hook-like
claws of unequal size. Last pair of legs very strongly built, and extending along
the sides of the urosome, distal joint large, sword-shaped, and armed with strong
spines at the tip.

Remark*. This genus was established in the year 1845 by Baird, to
include one of the 2 species described below. The 2 genera, Steropr and ('ni-illn*.
recorded by Goodsir, are both apparently synonymous with Baird's genus. Prof.
Brady erroneously referred the species of this genus to Pellnlunn Philippi, from
which the present genus is clearly distinguished both by the general aspect of
the body, and the structure of the several appendages. We know at present of
3 distinct species of this genus. 2 of which belong to the fauna of Norway.

38. Alteutha interrupta (Goodsir).

(PL XXXVI & XXXVII).
Sterope intn-nqita, Goodsir, Ann. & Mag. Nat. Hist. Vol. XVI, p. 32(i, PI. XI, tig. 10.

Sj-n: Altentlni hopyroidcs, Claus.
norvegica, Boeck.

r<'Jti(linni interniplum, Brady.
conophorum, Poppe.

Specific Character*. Female. Body rather compact, somewhat vaulted
above, and capable of rolling itself into a ball; seen dorsally, oval pyriform in
outline, with the greatest width in front of the middle, and gradually tapering
behind. Cephalic segment occupying about half the length of the anterior division,
postero -lateral corners rounded, rostral projection short, de-flexed, obtuse at the
tip. Epimeral plates of the 3 succeeding segments only slightly produced at the
posterior corners; those of last segment well defined, though less prominent than
the preceding ones, and evenly rounded at the tip. Urosome short and flattened,
with the genital segment broad and expanded in front, elypeil'orm: postero-lateral
corners of this and the 2 succeeding segments eonieally prodnerd. Caudal rami
only slightly longer than they are broad, subquadranglllar in form, and obliquely
truncated at the tip, tlie innermost but one of the apical seta' much dilated in
its proximal part. Eye large, placed near the frontal margin. Anterior antenna'
rather slender, 8-articulate, 2nd joint much the largest. Posterior maxilliprds

as

with the hasal part uniarticulate, hand narrow oblong in form. First pair of legs
very slender, with the first 2 joints of the outer ramus subequal in size, last joint
very small and armed with 5 claws gradually increasing in length inwards; inner
ramus much shorter than the outer, all 3 joints setiferous. Last pair of legs
with the proximal joint very short, distal joint oblong, flattened, with 3 strong
spines at the tip, and 2 smaller ones on the outer edge, surface transversely
rugulose.

Male differing but little from female in external appearance, though
easily recognizable by the more strongly built and prehensile anterior antennae.
Urosome distinctly 5-articulate, 1st segment much the largest and provided on
each side, at the postero-lateral corners, with a small appendage tipped with a
strong spine.

Colour dark chocolate brown, anterior part of cephalic segment lighter.

Length of adult female 1.20 mm.

Remarks. I think Prof. Brady is quite right in considering the Sterope
interrupta of Goodsir to be the present species, and as the specific name ~bopy-
ru'ules, proposed by Glaus and accepted by most other authors, is of much later
date, it ought to give place to that given to the species by Goodsir. The Alteutha
norveyica of Boeck is the same species, as is also most certainly the Peltidium
conophorum of Poppe. I have often met with specimens in which the middle of
the 3 setse issuing from the inner corners of the caudal rami has been broken
off near the base, giving it exactly the appearance figured by Poppe from his
solitary specimen.

Occurrence. This is one of our commonest Copepoda, occurring rather
abundantly along the whole south and west coast of Norway, at least up to the
Trondhjem Fjord. It is generally found in depths varying from 2 to 20 fathoms
among Laminariae and other algse, and is easily observable even to the naked
eye, on account of its dark-coloured body. It is rather an active little creature,
swimming about with considerable speed and a somewhat rolling motion, now
and then affixing itself to the fronds of the alga? or the walls of the vessel in
which it is observed. When disturbed, it rolls itself almost into a ball, and
remains in this attitude quite immovable for some time.

Distribution. British Isles (Brady), Heligoland (Glaus), Baltic (Poppe),
coast of France (Canu), Mediterranean (Canu).

64

39. Alteutha depressa, Baird.

(PI. XXXVIII).
il'jn-i-ssn, Bainl, Brit. Entomostraca, p. '2\*>, PI. XXX. figs. 1. -2.

S\n: Carillus oblongus, Goodsir.

Pcltldliun . 2>iii-jmri'i(in. White (not Pliilippi).

Alteutha purpurocincta, Norman.

Pcltiilinm </(/'/ *>/( >H, IJraily.

Eupelte purpurocincta,

Specific Cliiirncl'Ts. Female. Body much depressed, seen dorsally. oblong
oval in form, with the greatest width about the middle. Cephalic segment very
large, considerably exceeding in length the 4 succeeding segments combined,
postero-lateral corners acutangular, rostrum large and prominent, truncated at
tin- tip. Epimeral plates of the first 3 free segments of metasome acutely pro-
duced behind, especially those of 3rd segment. Last Segment with the epimeral
plates evenly rounded and far less prominent. Urosome short and broad, of a
structure similar to that in the preceding species. Caudal rami of exactly the same
appearance as in that species, apical setie, however, shorter, and none of them
conspicuously thickened at the base. Eye placed rather far back. Anterior
antenna? comparatively shorter and stouter than in A. intm-tt/it/i. and distinctly
9-articulate. Posterior antennae, mandibles, maxilla' and anterior maxillipeds of
a structure very similar to that in the preceding species. Posterior maxillipeds.
however, somewhat different, the basal part being distinctly biarticulate, and the
hand shorter and broader, oval fusiform in shape. First pair of legs comparatively
more robust, with the inner ramus almost as long as the outer, and without the
seta inside the middle joint. Natatory legs resembling those in A. infci'rtijitii.
except that in the inner ramus of 4th pair some of the seta? are spinit'onu. Last
pair of legs very large and robust, falciform, proximal joint rather large, distal
one conically tapered, and armed at the tip with 3 very coarse spines.

Body of a yellowish olive colour, with a dark purplish blue transverse
band across the middle, occupying the whole of the first. .''> free segments of
metasome. ,

Length of adult female 1.HO mm.

Rewtflrfe. Allthough the figures and description of this form given by
Baird are rather poor. I must agree with I'rof. Brady in thinking that they in
all probability refer to the present species. It is also, as opined by the same
author. \<T\ likely that the ('tirillu* ol^niiinx of Goodsir is the same species. Mr.
Norman, uho considered the species as new, described it under the name of

purpurocincfa, a name which has been accepted by several other authors.

65

The species has been referred by Canu and also by Th. Scott to the genus Eu-
pelte of Glaus; but in this view I cannot by any means agree, since Glaus ex-
pressly states that in this genus the inner ramus of the 1st pair of legs consists
of only 2 joints. It is true that the present species differs somewhat from A, inter-
rtt/>ta in the structure of the anterior antennae and posterior maxillipeds; but in
all other respects it exhibits so great a resemblance to that species, that it can
hardly be separated generically.

Occurrence. This form is not nearly so common as A. interrupt. I
have, however, taken it occasionally in several places off the west coast of Nor-
way, as also in the Trondhjem Fjord. It occurs in depths varying from 6 to 20
fathoms, on a sandy or gravelly bottom.

Distribution. British Isles (Brady), coast of France (Canu).

Gen. 17. Peltldium, Philippi, 1839.

Syn : Oniscidium, Glaus.
Reticulina, Cleve.

Generic Characters. Body short, flattened, strengthened with very con-
spicuous anastomosing chitinous stripes. Cephalic segment very large and ex-
panded, lateral parts not inflexed vent-rally; rostrum more or less prominent.
Epimeral plates of all the segments of metasome, including those of the last,
lamellarly produced, tongue-shaped, recurved. Urosome very short, with the
genital segment expanded on each side like those of metasome; distal part very
small and soft-skinned. Caudal rami narrow, with one of the apical setse
considerably elongated. Eye apparently consisting of 3 separate parts, one
median and 2 lateral. Anterior antennae comparatively short, 6 8-articulate.
Posterior antennae of about the same structure as in Altcutha. Mandibular palp
uniramous. Maxillae with the palp imperfectly developed, wanting the exopodal
appendage. Anterior maxillipeds with the outermost of the lateral lappets very
slender, terminal joint likewise exceedingly elongated and narrow, produced at the
tip to a short digitiform process. Posterior maxillipeds with the basal part uni-
articulate; hand very large. First pair of legs with the outer ramus resembling
that in Alteutha, inner comparatively broad, lamellar, biarticulate. Natatory legs
slender, of normal structure. Last pair of legs wholly obtected by the epimeral
parts of the body, biarticulate, falciformly curved, distal joint armed at the tip and
outer edge with strong spines.

9 Crustacea.

*. This j^enns was established as early as the year 1839 by
Philippi. to include the species described below. The genus Oniscidium of Glaus
is unquestionably identical with Philippi's genus, as is also the genus Reticulina,
recently established by Prof. Cleve. The genus is especially characterised by the
verv conspicuous net-work of chitinous stripes strengthening the body, as also by
the unusual development of the epimeral plates of the last segment of the meta-
some and the 1st of the urosome. Of the several appendages, the anterior max-
illipeds and the 1st and last pair of legs in particular are of a characteristic
structure. In addition to the typical species, 5 new species have recently been
n-corded by Mr. A. Scott from Ceylon. The form described by Prof. Cleve as
/iV tn-nhini iitiririlli from the Malay Archipelago is in all probability identical
with one of these species.

40. Peltidium purpureum, Philippi.

(PI. XXXIX & XL).

1'i-lfitlhtitt jiurpureinn. Philippi, Wiegnumn's Arcliiv f. Natuvyescliiohte 1839. p. 131, PI. IV,

tiLTS. 12, 13.

Syn: Oniscidiiini <in>nihii. Glaus.

Spet-i/ir Characters. Female. Hody, seen dorsally, oval quadrangular in
outline, greatest width in front of the middle and exceeding halt the length.
Cephalic segment very large, occupying nearly half the body, postero-lateral
corners acutely produced, frontal margin angular on each side, rostrum large
and prominent, transversely truncated at the tip. Free segments of metasome
each produced dorsally in the middle to a triangular, posteriorly-pointing pro-
jection; genital segment with 2 similar dorsal projections. Epimeral plates all
of uniform appearance, tongue-shaped and curving posteriorly; those of genital
segment extending beyond the extremity of the urosome, and having a much
smaller acute lappet behind. Caudal rami far apart, suhlinear in form, the inner-
most hut one of the apical setffl much coarser than the others, and exceeding the
iirovuine in length. Anterior antenna' not attaining half the length of the cephalic
inent. 7-artieulate and densely setiferous. 1st pair of legs with the 2nd joint
of the outer ramus somewhat longer than the 1st, last joint small and armed
with ') strong daws and a curved seta; inner ramus of ahout the same length
aa the outer, distal joint fully as long as the proximal one and provided at the
tip with 2 et|iial--i/.i'd seta', and at the inner edge with a much coarser ciliated
spine. La>t pair of legs with the distal joint evenly curved, and armed with 6
strong ciliated spines, 3 of which issue from the outer edge.

67

Male somewhat smaller than female, but otherwise of a very similar
external appearance. Anterior antennae, as usual, prehensile. Appendicular lappet
of genital segment replaced by a small trisetose piece.

Body in both sexes tinged all over with a rich carmine.

Length of adult female 1.05 mm.

Remark*. This is an easily recognizable form, being distinguished from
all our other Copepoda both by its general appearance and the beautiful colour
of the body. The Oniscidium armatum of Glaus seems to be identical with the
present species.

Occurrence. I have met with this form in several places on the west coast
of Norway, as also in the Trondhjem Fjord, in depths varying from 6 to 20
fathoms, sandy bottom. It is at once observable, even with the naked eye, owing
to its unusual colour.

Distribution. Scottish coast (Scott), Mediterranean (Philippi).

Fam. 7. Tegastidae.

Characters. Body short and compact, highly compressed, with very hard
integuments. Cephalic segment large, in some cases with a chitinous stripe across
the back, indicating the posterior limit of the head; lateral parts very deep and
terminating behind in a triangular promontory; rostrum short, deflexed, not de-
fined at the base. Epimeral parts of the 3 succeeding segments rudimentary.
Last segment of metasome more or less completely coalesced with the genital
segment, which more generally forms a large and highly chitinized dilatation
below, armed with variously formed projections. Distal part of urosome, as a
rule, very small and thin-skinned. Caudal raiui short, with the normal number
of setae. Eye well-developed, trilobate. Anterior antennas slender, 6 8-articulute,
and but sparsely setiferous; those in male transformed in the usual manner.
Posterior antennae 3-articulate, with a very small outer ramtis; terminal joint
wanting the usual geniculate setae. Oral parts, except the posterior maxillipcds
very small; the latter well developed, terminating in a strongly clawed hand.
First pair of legs imperfectly prehensile, both rami short, uniarticulate. Natatory
legs with the rami extremely slender, the inner one being the longer. Last pair
of legs of different shape in the two sexes, proximal joint in female greatly ex-
panded, in male simple.

/i 1 marks. The forms belonging to this family exhibit several apparently
very anomalous character-, e-pecially as regards tin- uvneral form of the body,
the structure of the 1st pair of legs, and the composition of the genital apparatus.
Yet in the structure of the greater nnmher of the appendages, they seem to come
nearest to the /'///'</////. \\\ spite of the very dis-imilar external appearance of
the body. Two nearly-related genera of this family are represented in the Nor-
\\euian fauna: and I regard the form recorded by Clans under the name of Am//-

N as the t\pe of a .'il'd -ellllS.

Gen. is. Tegastes, Norinan, L903.

Syn: Aiiii/itiinii-. fl:iii> (not

Generic ('lntnn-t<r.<. Body, seen laterally, almost circular in outline, with
the hack raucli cur\ed. and the genital segment greatly produced below. Outer
segments of urosome generally very short and retractile. Anterior antenna? 8-
articulate. with the first 2 joints considerably larger than the others. Posterior
antenn;e rather slender, with the terminal joint not dilated distally, one of the
apical spines very strong and prolonged; outer ramus Inarticulate, with the last
joint extremely minute. Mandibular palp uniramous, biarticulate. Maxilla' with
the palp elongated, biarticulate, exopodal and epipodal appendages wanting. An-
terior maxillipeds with the outermost lateral lobe considerably dilated at the end
and ean-yiiiLr .'! thiekisli seta', terminal joint scarcely produced at the tip. Poste-
rior maxillipeds with the ha-al part tiniarticulate. hand of dift'erent form in the
dift'Triit species. First pair of legs with the rami scarcely longer than the 2nd
bas.-d joint, the outer one considerably narrower than the inner. Natatory !
with both rami distinctly 3-articiilate. La-t pair of le^s of moderate si/e. inner
expan-ion of proximal joint in female triangular, distal joint very narrow and not
extending be\ ond the jtroximal. with ~2 slender setffi at the tip. \o true ovisac

present ill female. olil\ a -iliule OVUm beiliu r received belueeii the lamella' of the

last pair of legs. The ovoid spermatophore in male contained in a large cornet-
xhaped reservoir i--uing from the genital segment iii trout, and terminating in a
two-lipped, beak-like extremity.

/.' marks. This L r euus was est.-ibiisbed jn the year l*i'>:; by clans, to include

SOme V'TY peciiliai' Copcpoda. ->omc nf which lie found oil' I leligola nd. and others
in the Mediterranean. As however the generic name Ami/moitr jiroposed by him

69

had been used by 0. Fr. Miiller in quite a different sense, viz., to designate
some common larval forms (Nauplii), it cannot properly be accepted, and the
Canon Norman has therefore recently proposed to substitute for this name that
of Tegastes, the type being considered by him to be T. satyr us of Glaus, which
species certainly belongs to the present genus in the restriction here adopted.
No less than 5 different species referable to this genus have been observed by
the present author off the Norwegian coast.

41. Tegastes falcatus (Norman),
(ri. XLI).

Amymone falcata, Norman, Brit. Assoc. Beport, 1868, p. 296.

Syn: Amymone sphxrica, Brady (not Glaus).
rubra, Boeck (1872).

^l>ecific Characters. Female. Cephalic segment very deep, with the
postero-lateral corners greatly produced, acuminate; no chitinous stripe across
the back. Genital segment produced below into 2 strong, posteriorly-curving
hook-like projections. Distal part of urosome only very slightly projecting. The
innermost but one of the caudal setse peculiarly transformed, lancet-shaped. Pos-
terior maxillipeds rather powerful, with the hand oblong oval in form, and densely
ciliated along the palmar edge. Last pair of legs with the distal joint extending
to the tip of the inner expansion of the proximal one, the latter with 3 short
seise along the curved anterior edge, and 2 unequal ones at the tip.

Male a little smaller than female, and easily recognizable by the prehensile
character of the anterior antennre, and by the large, acutely-beaked spermatophore-
reservoir. None of the caudal setse transformed. Last pair of legs very narrow,
with the proximal joint small and simple.

Body of a golden yellow colour, variegated with a dark reddish brown
pigment, especially along the ventral face and the posterior edges of the segments.

Length of adult female 0.46 mm.

Remarks. This form was first briefly described by Norman from the
Shetland Isles as Amymone falcata. It was subsequently erroneously identified
by Prof. Brady with A. sphamca of Glaus, which is a very different species, and
does not even belong to the same genus. The form recorded by Boeck as A. rubra
is identical with Norman's species. It is the largest of the Norwegian species,
and is moreover easily recognizable by the dark red colour of the body, and by
the 2 very hooked projections of the genital segment.

70

Occur r< ii'-' . I have found this form not (infrequently in several places
off the west coast of Norway, as also in the Trondhjem Fjord; and Mr. Scott
also records it from Finmark (as .-1. .^jm-ricn). It generally occurs in depths
varying from 3 to 20 fathoms, on a sandy bottom, and is easily observable, even
with the naked eye. owing to its dark red colour and peculiar tremulous movements.

Distribution. J&ritish Isles (Brady), Shetland Isles (Norman). Arctic Ocean:
off Franz Josefs Land and Novaja Zemlia (Scott), Ceylon (A. Scott).

42. Tegastes flavidus, G. 0. Sars, n. sp.

(PI. I-XII. Ii-. 1).

r Chui-iirters. Femnlc. Cephalic segment about as in the preceding
species, with no trace of a chitinous stripe across the back. Genital segment
with 2 projections below, the anterior one obtuse at the tip and not recurved,
the posterior one broadly claw-shaped. Distal part of urosome much more pro-
minent than in any of the other species; caudal setae normal. Posterior maxil-
lipeds somewhat less strong than in the preceding species, with the hand narrow
oblong in form. Last pair of legs with the distal joint not extending to the tip
of the inner expansion of the proximal one. the latter only provided with 2 setae
in front. Spermatophore-reservoir in untie bluntly beaked at the tip.

Colour light yellowish gray.

Length of adult female 0.40 mm.

/.V///'//7,>. Though nearly allied to T. fttlcnlns. this form may be easily
distinguished by the blunt anterior projection of the genital segment, the feebler
posterior maxillipeds. and the unusually prominent distal part of the urosome.
The last pair of legs and the male spermatophore-reservoir are moreover somewhat
different in form. Finally, the colour of the body is rather different in the two species.

Occurrence. \ have only met with this f'nrin in 2 localities of the west
const of Norway. \i/.. at Kal\a;i^ and I'lg^esliiimes. In both places it occurred
rathd- sji.-irsely at a depth of about .'5 fathoms, muddy sand.

13. Tegastes longimanus (Glaus).

(I'l. XUI, Bg. 2).

.' Alijut"H' I'li/i/niiiiiiil. Chin-;. In.' t'rri|.'|pc'ii>l'ii ( ''>|i>'|>< "|IMI. |>. II"'. I'l. XX. li^'s. I :i. II.

('lni)-rlii.<. I-'iti/n/i. Cephalic segment with a distinct chitinous
-tripe across tin- back indicating the posterior limit of the head, postero-lateral

corners less acutely produced than in the 2 preceding species. Ventral protuber-
ance of genital segment narrowly produced, with the tip slightly hilobed and the
posterior edge projecting in a blunt tooth. Distal part of urosome only slightly
projecting, caudal seise normal. Posterior maxillipeds rather strong, with the hand
oval triangular in form, palmar edge angularly curved above the middle. Last
pair of legs resembling those in T. flaridus; inner expansion of proximal joint,
however, with 3 setse along the anterior edge.

Body of a pale yellow colour, and minutely speckled with reddish brown.

Length of adult female 0.33 mm.

Eemarls.li is with considerable hesitation that I refer this form to
Chius's species. Both the description of this species and the 2 figures given by
that author are rather poor, and scarcely suffice for an exact determination; yet
the form of the posterior maxillipeds, as represented by Glaus in fig. 14, exhibit
at any rate some resemblance to that in the present species. The characteristic form
of the ventral protuberance of the genital segment at once distinguishes this
species from any of the others here described; but unfortunately this part has
been wholly omitted in Claus's figure of the animal (fig. 13).

Occurrence. Some few specimens of this form were taken, together with
T. flavidus, at Eggesbonaes, west coast of Norway.

Distribution. Heligoland (Glaus), British Isles (Brady).

44. Tegastes grandimanus, G. 0. Sars, n. sp.

(PI. XLII, fig. 3).

Specific Characters. Female. Cephalic segment, as in T. longimanus,
provided with a distinct chitinous stripe across the back, postero-lateral corners
obtusely acuminate. Ventral protuberance of genital segment terminating in 2
unequal projections, the anterior obtuse, the posterior tooth-like and extending
behind. Distal part of urosome scarcely projecting. Posterior maxillipeds exceed-
ingly powerfully developed, hand very broad, with the palmar edge much curved
in the middle, and deeply concave below, dactylus strong and curved. Last pair
of legs with the distal joint rather short, extending little beyond the middle of
the inner expansion of the proximal one.

Colour not yet stated.

Length of adult female 0.42 mm.

Remarks This forms seems to be most nearly related to T. longimcmus
Glaus, but is of considerably larger size, and has the posterior maxillipeds much

72

more powerfully developed. In the form of the ventral protuberance of the genital
segment, it somewhat resembles T. fl/-i<lt{*: but the anterior projection is more
obtuse, and the posterior scarcely unguiform at all.

Occurrence. Only a single female specimen of this form has hitherto
come under my notice. It was taken in the same place in which 7'. lr>ii</ii>iniin*
occurred.

45. Tegastes nanus, G. 0. Sars, n. sp.

(PI. XLII, fig-. 4).

c Characters. Female. Cephalic segment, as in the 2 preceding
species, with a distinct chitinous stripe across the hack, postero-lateral corners
much produced, acuminate. Ventral protuberance of genital segment terminating
in 2 blunt projections, the posterior one recurved. Distal part of urosome only
slightly prominent. Posterior maxillipeds of moderate size, hand narrow oblong
in form, with the palm not defined. Last pair of legs resembling in structure
those in T. grandii>ians. Spermatophore-reservoir of mule rather thick, with the
beak short, recurved.

Colour yellow, variegated with chestnut-brown.

Length of adult female 0.31 mm.

Remarks. This is the smallest of the Norwegian species, and moreover
easily recognizable, when alive, by the light brown colour of the body.

Occurrence. In addition to the 2 above-mentioned localities of the west
coast of Norway, I have found this form occasionally at Aalesund and ('hristian-
sund in moderate depths.

Gen. ID. Parategastes, <*. o. Sars, n.

S\ n : AII/I>I<IIIC. Clans (purl ).

Generic Character*. General form of body resembling that in
the genital segment being expanded below in a similar manner, and the distal
part of the urosome much shortened. Anterior antenna; composed of only 6 or
7 articulations. Posterior antenna- with the outer ramus uniarticulate. Anterior
maxillipeds with the ~2 ]>n> \imal lateral lobes rephierd by simple setae, outermost
lobe less broad than in Tr<i/t*f<:<. and provided with only 2 seta? at the tip, ter-

73

minal joint produced at the tip to a long digitiform process. 2nd and 3rd pairs
of legs with the outer ramus very short, Inarticulate. Last pair of legs in female
very large, with the inner expansion of the proximal joint broad and vaulted,
distal joint somewhat dilated towards the end, with a single short apical seta.
No true ovisac present in female. Male spermatophore-reservoir very prominent.
RemarJcs.The type of this new genus is Amymone xplncrn-a of Claus,
which, though resembling the species of Tegastes, as regards external appearance,
exhibits some well-marked differences in anatomical details, which entitle it to be
separated generically. The 4 new species of Tegastes recently described by Mr.
A. Scott from Ceylon, also seem, according to the structure of the anterior antennae
and the natatory legs, to be more properly referable to the present genus.

46. Parategastes sphaericus (Glaus).

(PI. XLIII).
Amymone splicerica, Clans, Die freilebenden Copepoden, p. 114, PI. XX, figs. 1- 9.

Syn: Amymone nigrans, Scott.

Specific Characters. Female. Cephalic segment with a well-marked chi-
tinous stripe across the back, postero-lateral corners moderately produced, obtusely
acuminate, rostrum slightly prominent at the tip. Genital segment produced below
to a rather massive, nearly quadrangular prominence, with the anterior corner
somewhat exserted and tongue-shaped, the posterior unguiform and recurved, and
exhibiting in the middle, between the two, a smaller recurved dentiform projection
on each side. Distal part of urosome only slightly prominent. Anterior antennae
rather slender, 7-articulate. Posterior antennae with the outer rarnus extremely
small, bisetose. Posterior maxillipeds of moderate size, hand oblong fusiform in
shape. 4th pair of legs with the inner ramus extremely slender, terminal joint
linear, without any lateral setae, apex armed with 2 unequal spines. Last pair
of legs with the distal joint extending somewhat beyond the tip of the inner ex-
pansion of the proximal joint, the outermost of the lateral setae much elongated.

Male resembling the female in external appearance, but having the pos-
tero-lateral corners of the cephalic segment transversely truncated at the tip.
Anterior antennae, as usual, prehensile, with the 4th joint rather large, the last
claw-shaped. Last pair of legs very narrow, with the proximal joint not expanded,
distal joint linear, with 2 slender setae at the extremity. Spermatophore-reservoir
very large, terminating in 2 acute lappets.

'b*-
10 Crustacea.

74

Body of a dark cinereous colour, variegated with a sooty brown, or almost
black pigment.

Length of .-idult female 0.35 mm.

//' //"'//>. -There cannot in my opinion lie any doulit that this is the
true AmymoVH >////"r/V// of Clans, and the form recorded hy Hoeck under this
name is also unquestionably the same specie. Mr. Scott, who on the authority
of Prof. Brady helie\ed the Anii/iiiniir fulnilti of Norman to lie the ( 'lausian spe-
cies, descrihcd the present form as a new species under the name of J. )ii<irn*.
It is easily recogni/ed from any of the species of 7'rr/f /.-/ * hy the form and
armature of the ventral prominence of the genital segment, as also by the very
dark colour of the body.

Occurrence. -This form is rather common in the upper part of the Chris-
tiania Fjord, near the shore among al-a'. and also occurs occasionally off the
\\est coast of Norway. In spite of its small size, it is easily observable on ac-
cuiint of the very dark colour of the body, the animals, when alive, looking like
rapidly moving, black granules.

Distribution. Scottish coast (Scott), Heligoland (Claus), coast of Krance
1 1 'aim t. Mediterranean (Claus), Ceylon (A. Scott).

Fam. 8. Porcellidiidse.

( 'li'ii-iirl<'i-x. Body much depressed, shield-like, with some of the segments
imperfectly defined, and with the urosome short and flattened. Inarticulate. An-
terior antenna 1 short, and composed only of a limited number of articulations.
P'l-terior antenna- .'l-ai'ticulate, with a well-developed outer raimis. ( )ral parts on
the whole of rather peculiar structure, mandibular palp \er\ largeh de\eloped:
posterior maxillipeda imperfectly siihchelilbrm. Kirst (>air of legs with both rami
flattened and \er\ dissimilar, the' inner one distinctly prehensile. Nataton legs
normal. \ <;(<\ paii' of le-s ver\ differeiit in the two sexes. Sexual difference on
the whole very much pronounced. A single flattened ovisac present in female.

/>'< ,IK/,/,-<. This family is as yet only represented h\ a single ^eiius. vi/..
/',,rr//nl/iiiii Claus. which in several respects deviates considerably from the typical
Harpacticoida. In the short depressed form of the body, it somewhat recalls the

75

Pelinlnthe, to which family it was indeed referred by Claus; but the structure of
the several appendages is very different, and more approaches that in the fol-
lowing family, the Idyldiv.

Gen. 2<. POrCellidium, Claus. 18(50.

Syn: Tliyone, Philippi (not Oken).

Generic Characters. Body short and flattened, with the cephalic segment
very large and expanded; rostrum broad, lamellar, not denned at the base.
Epimeral plates of the first 2 free segments of metasome tongue- shaped, those
of 3rd segment in female rudimentary, in male well developed. Last segment in
both sexes without any trace of epimeral plates, and in female imperfectly defined
behind. Urosome short and flattened, in both sexes composed of only 2 segments,
the anterior one large and lamellar, the posterior small, subquadrate. Caudal
rami more or less lamelliform, with very short apical seise. Eye present, of usual
structure. Anterior antennae short, 6-articulate, in male strongly prehensile.
Posterior antennae with the outer ramus uniarticulate. Mandibles very strong,
with the palp excessively large, lamellar, indistinctly 3-lobed, and provided out-
side with numerous thick plumose setse. Maxillse with the palp normally developed.
Anterior maxillipeds comparatively short and stout, with 2 unequal setiferous
lobes inside, terminal joint rather broad, incurved, with several strong spiniform
setse on the tip. Posterior maxillipeds rather small, 3-articulate, 1st joint pro-
vided in front with an oval ciliated lamella, 2nd joint tapered distally, with a
short deflexed lobe inside, last joint very small, with 2 short incurved claws at
the tip. First pair of legs with the outer ramus 3-articulate and very delicate,
being edged outside with soft plumose setae, inner ramus biarticulate, 1st joint
large and triangular in form, last small and armed with 2 subequal claws, densely
fimbriate on one side. Natatory legs with both rami 3 -articulate, inner ramus in
1st pair much larger than in the 2 succeeding pairs. Last pair of legs in female
distinctly biarticulate, distal joint large, lanceolate; those in male much smaller,
uniarticulate, sub-quadrate, terminal edge aculeate.

Remarks. This genus was established as early as the year 1839 by
Philippi, to include a Mediterranean species, T. viridis; but as the name Tlii/mn
proposed by him had been previously appropriated by Oken for a genus of Holo-
thuroida, it was changed by Claus to Parcel Htliitm. The latter author records 3

76

species of this genus from the Mediterranean, one of which may be the
riritl/s of Philippi, and Mr. A. Scott has recently added 3 new species from
Ceylon. To the Norwegian fauna belongs only a single species, to be described
below.

47. Porcellidium fimbriatum, Glaus.

(PI. XLIV & XLV).
J''i'i-JHiUinn fimbriatum, Clans, Die freilebenden Copepoden, p. 140, 1M. XX11, fig. 1. .

Syn : Porcellidium fasciatum, Boeck.
viride. Brady (male).

subrotundum, Norman (young).

a. Female. Body oval quadrangular in outline, width
somewhat exceding ~/ z of the length. Cephalic segment very broad and flattened,
obtusely truncated in front, with the lateral corners rounded ; rostrum slightly
prominent, broad, lamellar, truncated at the tip. Epimeral plates of the 2 suc-
ceeding segments large and closely contiguous, being, like the cephalic segment,
surrounded by a narrow hyaline rim; those of 4th segment very small and easily
overlooked. Last segment imperfectly defined. Urosome almost semicircular in
outline, genital segment expanded on each side to a thin lamella finely ciliated
at the edge and encompassing laterally the small quadrate terminal segment to-
gether with the caudal rami. The latter spatulate in form, about twice as long
as broad, and slightly widening distally, tip transversely truncated and provided
with 5 very small setse, one of which issues from the inner corner, the others
nearer to the outer one; moreover 2 similar setse issue from the dorsal face of
each ramus. Anterior antennae scarcely extending beyond the antero-lateral cor-
ners of the cephalic segment, angularly bent at the base, and consisting of 6
articulations rapidly diminishing in size distally. Posterior antennae with the 1st
joint much larger than the others, outer ramus about the length of the middle
joint, and carrying 6 plumose setse. First pair of legs with the outer ramus
gradually tapering distally, 1st joint much larger than the others, seta? of outer
edge bulbously dilated at the base, terminal joint with 4 such setae, and more-
over with a slender apical spine and a strong plumose seta inside. Last pair of
legs with the distal joint very large, lanceolate, extending between the epimera
of the 2nd free segment of metasmne and the lateral expansions of the genital
segment, so as to look like a pair of epimeral plates. 1 ) Ovisae. almost wholly
covered by the urosome.

') They have ;ilso bri'ii n-^nnlrd us such by 1'rol'. l!r:idy. \vhu rn , iiu-i msly describes
the lateral r\|iaii-i'ni of tin- ^mital segment a.s the last pair uf kg.s.

_ 77

Male considerably smaller than female and of a rather different external
appearance. Cephalic segment transversely truncated in front, with the lateral
corners sub-angular; rostrum almost obsolete. 3rd free segment of metasome
with w T ell-developed epimeral plates of the same appearance as those of the 2 pre-
ceding- segments. Genital segment but slightly expanded, and not encompassing
laterally the distal part of the urosome. Caudal rami much shorter than in fe-
male, being considerably broader than they are long. Anterior antennse very
strongly built and angularly bent at the base, 4-articulate, 3rd joint considerably
dilated, last joint unguiform and very mobile. Last pair of legs spatulate, inter-
calated between the epimeral plates of the 3rd free segment of metasome and
the urosome, tip obliquely truncated and armed with a row of 6 short spines.

Body in both sexes of a clear yellowish green colour, and generally
provided dorsally with a dark violet transverse band across the posterior part
of the cephalic segment, urosome in female tinged at the base with a similar colour.

Length of adult female 0.90 mm., of male 0.60 mm.

^Remarks. The remarkable sexual difference occurring in this form has
led Prof. Brady, and perhaps also Claus, to describe the two sexes as 2 different
species. There cannot, in my opinion, be any doubt that the form recorded
by Prof. Brady as P. riridv, and regarded as identical with P. dentatum of Claus,
is nothing but the male of the present species. True, a figure is also given of
the supposed female of P. viride; but the specimen drawn is certainly not adult,
and appears to be a young male, in which the anterior antennse have not yet
been fully transformed. Nor can I doubt that the P. subrotundum of Norman
is founded upon immature specimens of the present species (compare the figure
of such a specimen given on the accompanying plate). The Porcellidium fasciatum
of Boeck is not, as opined by Prof. Brady, identical with Aspidiscus favciutti*
Norman, but is most certainly the present species. Whether Philippi's species is
the male of this species or a distinct form, it is very difficult to decide. The female
of the present species, at any rate, is easily recognizable by the greatly expanded
genital segment and by the characteristic form of the caudal rami.

Occurrence. I have met with this form rather frequently in several places
on the west coast of Norway, as also in the Trondhjem Fjord. It lives, as a rule,
on the fronds of Laminarise, to which it applies its flattened body so closely,
that it is only with great difficulty that it can be loosened from its hold, when
alive. On employing its natatory legs, the animal runs about rather quickly along
the fronds or other smooth objects, with an even, gliding motion.

Distribution. British Isles (Brady), Mediterranean (Claus), Ceylon
(A. Scott).

78

Fam. 9. Idyidae.

rx. Body more or less depressed, with the posterior division be-
coming abruptly much narrower than the anterior, both with the normal number of
segments. Eye distinct or wanting. Anterior antennae more or less slender, 8- or
9-articulate, distinctly prehensile in male. Posterior antennae 3-articulate, with
the outer ramus well developed. Oral parts differing somewhat in structure in
the different genera. First pair of legs, as a rule, with both rami 3-articulate,
but of rather different structure, the inner one generally the longer and always
prehensile. Natatory legs normal. Last pair of legs more or less extended
laterally, proximal joint but slightly expanded, distal joint more or less elongated.
A single ovisac present in female.

]\rniark*. The forms belonging to this family are chiefly characterised
by the sharp demarcation between the anterior and posterior divisions of the
body, the former being more or less expanded ami depressed, the latter abruptly
much narrower. In the structure of the several appendages, some approach may
be found, partly to that in the Poycclliiliiilti'. partly to that in the Thnl^tr'nl"'.
The shape of the last pair of legs is, however, rather different from that in either
of those 2 families, and agrees more with that found in the Peltidiidce. AYe
know as yet of 6 different genera belonging to this family, all of which are re-
presented in the fauna of Norway.

Gen. '2\. ASpidiSCUS, Norman. L868.

S\n: Scnli-Uiilnun. l!r;idy (not Clan-).

('< IKT'IC Characters. Anterior division of body much expanded and de-
pressed, clypcil'orm, with the dorsal face slightly vaulted and very smooth. Ce-
phalic segment large and evenly curved in front, and, like the epimeral plates.
bordered by a narrow hyaline rim; rostrum lamellar, distinctly defined at the
base. Kpimeral plates of the first 3 free segments of inetasome well developed,
imbricate, recurved: .'!rd segment fornicate behind, arching over the very small
la>t ^cLMnent. as also over the anterior part of the nrosome. The latter abruptly
much narrower than the anterior division and gradually tapering distally, genital
segment scarcely expanded. Caudal rami very small, but with the apical setae
much elongated and extending straight backwards. Kye distinct, of usual

79

structure. Anterior antennae of moderate length, not dilated in the middle, 9-
articulate. Posterior antennae with the apical setae comparatively short, outer
ramus fully as long as the inner and 3-articulate, with one of the apical setae
much elongated. Mandibular palp rather large and complex, produced in front
to a digitiform, finely ciliated process. Maxillae with the epipodal plate very
large and tipped with 2 exceedingly strong plumose setae, Maxillipeds com-
paratively small and simple in structure, the anterior ones without any lateral
lobes, terminal joint small and tipped with 2 ciliated spines; the posterior ones
with a single comparatively short claw at the tip. First pair of legs rather large
and of a very delicate structure, with both rami flattened and somewhat resembling
those in the genus Porcellidium; inner ramus, however, distinctly 3-articulate,
with the 1st joint large and dilated in the middle, the outer 2 comparatively
short, last joint carrying 2 digitiform claws densely fimbriate on one side. Na-
tatory legs with both rami of nearly equal length, middle joint of inner ramus
in 1st pair with 2 setae inside, in the 2 succeeding pairs with only one. Last
pair of legs differing somewhat in shape in the two sexes, those in female rather
coarse, with the proximal joint elongated and scarcely at all expanded, distal
joint more or less lamelliform.

Remarks. This genus was established by Norman in the year 1868, to
include a form found by him off the Shetland Isles and named A. fasciatus. The
genus was not, however, accepted by Prof. Brady, who in his Monograph referred
Norman's species to the genus Scutellidlnm Glaus (= = Psamathe Philippi), to which
genus it certainly exhibits a close relationship. I think, however, that Norman's
genus ought to be maintained, since 2 nearly-related species exist showing the very
same characteristic differences from Claus's genus, which likewise comprises 2 or 3
closely-related species. The most characteristic feature of the present genus
consists in the peculiar fornicate condition of the 3rd free segment of the meta-
some, a character not found in any other Copepoda with which I am acquainted.
Moreover, on a closer comparison, several well-marked differences are found to
exist in the structure of some of the appendages. The genus comprises, as above
stated. 2 well defined species, to be described below.

48. Aspidiseus littoralis, G. 0. Sars, n. sp.

(PI. XLVI & XLVI1).
Syn: Scutditdhim fasciatum, Brady (not Norman).

Specific Characters. Female. Anterior division of body very broad,
scarcely narrowed behind. Cephalic segment large, occupying more than half

the length of the anterior division, edges evenly curved throughout, postero-
lateral corners acutely produced and applying closely against the 1st pair of
epimeral plates; rostrum but slightly projecting, broad, lamellar, with the terminal
edge evenly curved. Epimeral plates of the first 2 free segments of metasome
much produced and closely imbricate; those of 2nd segment extending as far
hack as the tip of the succeeding pair. 3rd segment highly fornicate behind,
wholly obtecting the last segment and the anterior half of the genital segment,
posterior edge slightly arched and bordered with a broad hyaline rim. Urosome
scarcely l /z as long as the anterior division, and having the segments very sharply
defined. Caudal rami extremely small, the innermost but one of the apical setce
almost 3 times as long as the urosome. Anterior antennae scarcely more than
half as long as the cephalic segment and rather narrow, terminal part slightly
exceeding in length the 2 preceding articulations combined. Posterior antenna'
with the spines outside the terminal joint coarsely denticulated on the one side.
Last pair of legs rather elongated and curving evenly behind, proximal joint only
very slightly widened towards the end, distal joint about the same length as the
proximal one, and narrow oblong in form, with 4 delicate setre at the end, outer
face and edges densely hairy. Ovisac large, rounded oval, and somewhat flattened.

M'tlf considerably smaller than female, and having the anterior division of
the body less expanded, and oval in outline. Epimeral plates less produced, those
of the 2nd free segment of metasome not extending to the tip of the succeeding
pair. Urosome narrower and distinctly 5-articulate. Anterior antenna? more
strongly developed than in female, and hinged between the 5th and (ith articu-
lation. Last pair of legs considerably smaller than in female, with the proximal
joint much shorter than the distal one.

Body in both sexes generally of a uniform golden yellow colour, occa-
sionally exhibiting on the back 2 irregular patches of a dark red hue. the one
occupying the centre of the cephalic segment, the other the dorsal part of the
.".rd free segment of metasome.

Length of adult female about 1 mm., of male 0.70 mm.

/.'' nuti'l.:--. This fi.rm has been described and figured by Prof. Brady in
liis well-known Monograph, as Sriil,-/li<lii<in /'tixrittlifin. as it was believed to be
identical both with the form recorded by Boeek as furrr/liil/nni l'xc'nit/tiii. and
with that described by Norman as . |\//^//.vf//x fnxc'ialn*. It has been stated above
that Boeck's species is undoubtedly quite a different form. vi/.. /'o/rc///</m/// /////-
ln-'i<il nut Clans, and 1 also regard it as beyond doubt that Norman's rather full
description of his A*i>i<lisi-n* /'nsrinl/ts does not refer to the present, but to the
next species, for which reason it has been necessary to give a ne\\ specific name

Harpacticidae.

Copepoda

Harpacticoida.

Pl.XXXffl

1 .

*

; >
^

G.O.Sars autogr. Norsk Lithqr. Officin.

Zaus spmatus, (Goodsir.)

Harpacticidae.

Copepoda

Harpacticoida.

PL JQKIV.

G.O. Sars autoqr. -y r> r\ O ~

Zaus abbreviatus , G.O. oars.

Norsk Lithgr. Officm.

Copepoda

Harpacticidae. Harpacticoida.

PL XXXV.

iV

.. /

,

G.O. Sars autogr.

Zaus Goodsiri , Brady

Norsk Lithgr. Officin.

Peltidiidae.

Copepoda

Harpactieoida.

Pi. xxxvi.

-,

:-

* . ^_ . /

.

V \!>^_-#

:

V-StitVi^fJ^-r . >ffl'

ft

G.O.Sars autogr. Norsk Lithgr. OfTicin.

Alteutha interrupta (Goodsir.)

Peltidiidae

Copepoda

Harpacticoida.

G.O. Sars autogr. . , Norsk Lithgr Officin

Alteutha mterrupta (GoodsirJ

i /-. ,. ~ -t-i ^i \

Peltidiidae.

Copepoda

Harpacticoida.

PI. -XXXVI II

I i .-./, _ .j. ', '._

Hf^

/^ - """, ' c 'r

:

G.O, Sars autog r.

Alteutha depressa, Baird

Norsk Lithgr. OfTicin.

Peltidiidae.

Copepoda

Harpacticoida.

Pl.XXXK.

**,

>;

?

itf^^ J _** "" ~^ *^

' "\f *^

f .s' v

^4

ij

G.O. Sars autogr. . Norsk Lithgr. Officm.

Peltidium purpureum, Phil.

Peltidiidae

Copepoda

Harpacticoida.

GO. Sars autogr. ... _, ., Norsk Lithgr. Officin.

Peltidium purpureum, Phil,
(continued)

Tegastidae

Copepoda

Harpacticoida.

PL XL!

V-,

/?,-

.

\ M

1 1 Jri. ,, i

,/zy-

<

. ^

t. -^

!

1 m

- |H

'lf^ ::. i 'A>a

/I
I

G 0. Sars autogr.

Norsk Lithgr. Offlcin.

Tegastes falcatus, Norman.

Tegastfdae

Copepoda

Harpacticoida.

PI. XLH

<ffly\ I i i *v. -, t IFF - :

: "M< .;> A :.... I >^

m

/A-

G.O.Sars autogr. Norsk Lithgr. Officin.

ITegastes flavidus, G.O. Sars.-2.T. longimanus,(Cls).-
S.T.grandimanus, G.O. Sars.-4.T.nanus, G.O, Sars.

Tegastidae

Copepoda

Harpacticoida.

PI. XLEI.

G.O.Sars autogr. Norsk Lithgr. Qfficin.

Parategastes sphaericus (Glaus)

Porcellidiidae

Copepoda

Harpacticoida.

Fl.XLK

^ . r v ? ? '' ,- -..-- 'TKifc-'iF-- u.^4 1* L Hi - rt.' r.if'" . t_ii '.,1

G.O. Sars autogr.

Porcellidium fimbriatum , Cls .

Norsk Lithgr. Officin.

Porcsliidiidag

opepoda

Harpacticoida.

H.XLV

G.Q.Sars autogr.

Porcellidium fimbriatum CIs
(continued)

Norsk Lithgr. Officin.

idyidae

Copepoda

Harpacticoida.

PLXLVI

,< ^

,

iPTi

2 ' I - *-' ' (

xK i I ' %

' I i

$ ' i

i ;^|;; . i 1

'/> ,J( ' ;-,- r. ''>,' 'i-' 1 -** 1 .-* ' V

-"" '-

, I ' I

It' '-t \Jc ' ' ''-. S"'Xi"*y>-''."* !r ' : i

xoi 'B ' -^sjg'f '' " .-*>- ' / ] !'.(

^ ; ] ': . ,&21f S * '

^ / I ' .. ^.^'^^^ : !'' -

,p / ,^.,.^@2 ii^:";-fe>;^

X" '.. ' ' ? ' , ill', \ X 1 -^,''

''/-? \ t '

'/A^f, nnM

m \

:/ \/

/ ; \^"^^' ^ 3

// ; 1 C- J-^ : fS ';

/ A; ,,' i -, : -71^^- V* ' '

! . ' : " , ^i-n-^L^^a- v " /

^ r^Tj? i -'

: ' M-il^/^^4

^- '/ ' r ' ;.-f/ i

^-w r^^v

x --jv M /.-,v .

'
-'

^i /./%
i I

^ ; v '

cs p ;

' ; I I fi ^ i!
^ K 1 M

Hi S ; ' -f~~

M

^ -- ifr^^

!' i SS
tfl ---h --4.,, i

G.O.Sars autogr.

^ rt c

Aspidiscus Siitorahs, G.O.

Idyidae

Copepoda

Harpacticoida.

FLXEVH

la.O. Sars autoqr.

.. ^ n o

Aspidiscus httorahs, G.O. Sars.
(continued)

Norsk Lithgr. Officin.

idyidae

Copepoda

Harpacticoida.

FLXLW

, A,

>

; </

* tSv- ffv ** ^t^ fc'J '\"L xi I

I ;:

v

'

ICitf;

: '51Pig^-U^-^^^-?V '

/: ; ! vTl!:; .%

/ .>;;:-'- ;.". ---3 ti^ ;/'..-,. ;^/i. M.>

ift ,'Xs;/f ? ',-,:-':''' , ; ; . i .- \

\ /M

/? / n t it Vi x i\

i /J JO

' ^-

IIIII

mm

\*M1r.M$\

l.v JAWX'/? ;'A\v v '-fi'W/'K f'./AvAi!

^.wi 'im

G.O.Sars autogr.

Aspidiscus falcatus, Norman

Norsk Lithgr. Officin.

AN ACCOUNT

OF THE

CRUSTACEA

OF

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPAGTICOIDA

PARTS VII & VIII

IDYID^E (continued), THALESTRID^E (part)

WITH Iti AUTOGRAPHIC PLATES

BERGEN

PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMERMEYER'S FORLAG, CHRISTIANIA

1905

81

to the species "here under discussion. It may easily be distinguished from Norman's
species by its more robust form, and especially by the great development of the
2nd pair of epimeral plates in the female. The colour of the body is morcmrr
rather different in the two species.

Occurrence. I have taken this form rather abundantly in some places on
the west coast of Norway, for instance, at Haugesund, Kopervik and Bukken. It
is a sub-littoral form, being found close to the shore on the fronds of Lamwana
<lit/itta at low-water mark. The animal, like the species of PorceH/iUniii. has
the power of applying its body very firmly to any objects, so that it can only
be loosened with considerable difficulty when alive. After the collecting-vessels
have been emptied therefore, the greater number of the specimens remain in the
bottles, firmly attached to the sides. On shaking the bottles with some fresh water,
however, the specimens very soon leave their hold and can be emptied out with
the water. In this manner I was enabled, during my last excursion, to secure a
great number of specimens.

Distribution. British Isles (Brady).

49. AspidlSCUS fasciatus, Norman.

(PI. XL VIII).

Aspidiscus fasciatus. Norman, Last Report on Dredging among the Shetland Isles. Brit. Assoc.

Report for 1868, p. 298.

Specific Characters. Female. Very like the preceding species in its ge-
neral appearance, but of somewhat smaller size and less robust form of body.
Anterior division broadly oval in outline, slightly narrowed both in front and
behind. Eostrum somewhat more prominent than in A. littoralis, though exhibiting
a very similar form. Epimeral plates of the first 3 free segments of metasome
less produced behind, 2nd pair not extending nearly as far as the tip of the
succeeding pair; posterior edge of 3rd segment straight, scarcely at all limbate.
Last segment of metasome, as in the preceding species, wholly obtected by the
fornicate hind part of the 3rd segment. Urosome with the segments somewhat
less sharply defined than in A. littoralis. Caudal rami extremely small, but with
the apical setae excessively elongated, the innermost but one almost attaining the
length of the whole body. Antennae, oral parts and anterior pairs of legs of almost
exactly the same structure as in A. littoralis. Last pair of legs, however, differ-
ing conspicuously in form; proximal joint less curved, and considerably dilated
towards the end; distal joint shorter than the proximal one, and broadly oval or

11 Crustacea.

82

lamelliform. being coarsely denticulate both at the edge and the outer face, mar-
ginal Betffi MTV delicate, and only :> in number.

M" : .-mbling that of tin- pi- -ceding species, but somewhat more slender

in fiinn.

l'.ml\ in both sexes of a pah- \elhnv colour, with a broad transverse
Kami of a rich crimson across tin- back, occupying the dorsal parts of the tirst

_'iuents ..|' nietasonie.

I. .ii-th of adult female 0.80 nun.. of male u.iiu mm.

/.'<//<>///>. This is unipie>tionabl\ the species originally described by Nor-
man from thr Shetland Nlcs nndei- the above name. His statements about the
colour of the animal 1 ) leave no doubt as to the correctness of this assumption.
Though very nearly related to the pn 'ceding species, this form may be easily
iiiLMiished l.y the le-> robust body, hut especially by the uniform appearance
if tin- rpimeral phi' The form of the last pair of legs in the female is al>o

conspicuously different, and. as above -tated. the colour of the body is very
characteristic.

nee. I have found this form not (infrequently in several places

on the west .-oast of Norway, as also in the Trondhjem Fjord. It occurs only in
depths varying from ii to I'D fathoms, generally on Lnin'inni'tu tnci-lnti 'n/n. but also
on other al.u f :'. and never in the littoral /one.

/ )i*tril>iiHf,it. -Shetland Isles (Norman).

Gen. 22. Psamathe, I'liilippi. ISKi.

S\n: Srul,-U'nli\nn. Glaus.

' luinicl' , . \nterior division of bod\ -oineuliat depressed, though

ly 1\ peiiorm. and \\ithout an\ hyaline rim at the edges. Rostral projection

obtuse, not lamellar, nor distinctly delined at the hase. Kpimeral plates of the

tirst :; free segments of metasome discontig ...... s at the tips, not imbricate. Last

nient of metas,,me |'reel\ exposed behind. \ery small, and without any distinct
epimeral pl.-r I'rosome more m- less elongated, and slightly dilated in its

anterior p; t rt. uidal rami well developed, though rather shoi't. apical seta-

-lender :md -omewhat di\ ei -ent. |-!\ e normally developed. Anterior antenna'

''"I'i'ir |-;il''. "itli a nili\-ri,|,,nrr.| l'.i-ci;i ,.n id,. L>i,,l :iinl :Jnl. nrLJinl. :!nl. and lili
! '-"|'li:i: ' 1111:111).

83

(in female) somewhat dilated in the middle, 9-articulate, terminal part abruptly
narrowed. Posterior antennae with the outer ramus less fully developed than in
Aspidiscus. Mandibles, maxillse and anterior maxillipeds of a structure very similar
to that in the above-named genus. Posterior maxillipeds, however, differing in the
presence of 3 strong claws at the tip. First pair of legs, as in Aspidiscits, very
delicate, with both rami 3-articulate, though differing conspicuously in structure
from those in that genus, outer ramus much shorter than the inner, with the
terminal joint very small, and carrying on the tip a number of closely-disposed
pulvilliform spines; inner ramus with the 2nd joint well developed, the last one
carrying 2 densely fimbriate spines. Natatory legs with the middle joint of the
inner ramus in all pairs carrying 2 setae. Last pair of legs less strongly built
than in Aspidiscus, proximal joint comparatively short and bilobed at the end,
distal joint oblong, lamellar. Ovisac normal.

Remark*. This genus was established by Philippi in the year 1840, to
include a species found by him in the Mediterranean at Sorrento. The genus
Scutellidium of Glaus is unquestionably identical with Philippi's genus, and as
that name is of much later date, it must cede the place to that proposed by
Philippi. The genus is nearly allied to Aspidiscus, but differs in some characters
rather conspicuously, both as regards the external appearance of the body and
the anatomical details. In addition to the typical species, 2 other closely-related
forms have been described, the one, Scutellidium Arthur i Poppe, from the Behring
Sea, the other, 8. plumosum Brady, from New Zealand.

50. Psamathe longicauda, Philippi.

(PI. XLIX).
Psamalhc luiKj'iatwla, Philippi. in Wiegm. Archiv f. Natuvgesch. 1840, p. 189. PI. IV, iig. 1.

Syn: Scutellidium thisboides, Claus.

Specific Characters. female. Anterior division of body moderately ex-
panded, oval in form, and scarcely at all narrowed behind. Cephalic segment
occupying about half the length of the anterior division, and gradually contracted
anteriorly, front narrowly rounded. Epimeral plates of the 3 succeeding segments
of moderate size, discontiguous at the tips; 4th segment rather broad, with tlir
posterior edge only very slightly incurved in the middle. Last segment of meta-
sorne extremely small, but wholly uncovered. Urosome about half the length of
the anterior division, and gradually tapered behind; genital segment somewhat
dilated in front, and imperfectly divided in the middle, lateral edges in this and

84

tin- '2 Miecr.-ding segments finely ciliated; anal segment comparatively short and
deeply incited in the middle. Caudal raini about as long as they are broad and
transversely truncated at the tip. apical seta' much elongated, the innermost but
one exceeding twice the length (if the urosome. Anterior antenna 1 rather robust
and deiiseh setiferous. the first 3 joints rather large and inflated. 4th joint much
>ln>rter and produced at the end anteriorly to a conical process carrying the
sensory filament, terminal part abruptly attenuated and not attaining half the
length of the proximal part, last joint linear and fully as long as the other 4
combined. Posterior antenna; with the outer ramus scarcely exceeding half the
length of the inner, and 4-articulate. First pair of legs with the outer ramus
scarcely longer than the basal joint of the inner, and carrying on the tip 4 pulv-
inular. recurved spines accompanied by a slender ciliated seta. Last pair of legs
with the terminal joint more than twice as long as the basal one. and narrow
lozenge- shaped in form, with one short apical seta and 4 more slender lateral
ones, edges of the joint densely hairy.

Colour yellowish, with a more or less distinct rosy tinge, outer part of
anterior antennae dark violaceous.

Length of adult female 0.88 mm.

//' Him-/,:--. The above-described form is unquestionably that recorded by
Chins and other authors as Scutellidium ////V>o /</*>. the identity of which with
Philippi's r^iiiinilln /t,ni/'irtiii<lti I cannot doubt. Whether the 2 forms described as
Si-iit, Hull, mi Ai'fhnri Poppe and S. jiln-nn^tim Brady, are in reality specifically
distinct from the type, seems to me somewhat questionable.

Occurrence. This form seems to be of very rare occurrence off the Nor-
wegian coast. I only succeeded last summer in securing a few female specimens
;it Kopervik and Bukken in the lower part of the Stavanger Fjord. The spe-
cimens occurred together with A*iii<lixcn* /ittni-u/is close to the shore on the
fronds of I,<IIII'IH<II-'I<I il/i/it/itu at low-water mark.

/i'~h i/Hiti'iii. British Isles (Brady), coast of France (('ami), Mediterranean
(I'hilippi. Clans), Black Sea (Karawaiew), ? Fran/, Josef Land (Scott).

Gen. :>:*. MaehairopUS, I'.rady. iss;{.

leric Characters. Anterior division of body much depressed, with the
cephalic segment \er\ large, rostral projection obtuse, not defined at the base.

85

Epimeral plates of the 3 succeeding segments discontiguous at the tips. L;isl
segment of metasome very small, but wholly exposed. Urosome of modern! <>
length and much narrower than the anterior division, genital segment distinctly
divided in the middle. Caudal rami resembling those in L'xauitilhr, but witli the
apical setce less elongated. Eye quite normal. Anterior antennae comparatively
slender, 9-articulate, not dilated in the middle. Posterior antenme with the outer
ramus more fully developed than in Psamathe. Mandibles with the palp rather
large, though of quite normal structure. Maxillae with the epipodal lobe well
developed and, as in Psamathe, carrying 2 large plumose setae. Maxillipecls com-
paratively more strongly built than in that genus, the anterior ones with 2
well-developed lateral lobes, the one close to the base, the other at the junction
with the slender unguiform terminal joint; the posterior ones terminating in a
strong claw accompanied by 3 or 4 slender setae. First pair of legs with the
inner ramus much as in Psamathe, outer ramus rather short and stout, with the
middle joint thickened, and armed on the lower face, close to the base, with a
strong, claw-like spine curving outwards, last joint very short, with the 4 apical
spines not pulvinular, being bent outwards and, like those in the genns Idya.
densely ciliated along the outer part of the anterior edge. Middle joint of inner
ramus in 2nd pair of legs with 2 natatory setae, that in the 2 succeeding pairs
with only a single such seta. Last pair of legs comparatively smaller than in
Psamathe, and more lamellar.

Remarks. This genus was established in the year 1883 by Prof. Brady,
to include a species, M. idyoides Brady, found during the Challenger Expedition
at the Kerguelen Islands. As observed by that author, the genus is somewhat
intermediate between Psamathe (Scutellidium) and Idya, resembling in some par-
ticulars the former genus, in others the latter. Among the characters assigned to
this genus by Prof. Brady, is the presence of 2 widely-distant eyes; but this
statement must, I suppose, be due to a miscomprehension, the chitinous thicken-
ings at the insertion of the anterior antennae having in all probability been mis-
taken for eyes. The true visual organ, as in most other Harpacticoida, very soon
becomes inconspicuous in preserved specimens through the dissolving action of the
alcohol. There still remain, however, sufficient characters in support of this genus;
and its validity is moreover now proved by the discovery in the northern oce;m
of another form, which, though closely agreeing with the type in all essential
anatomical details, is yet evidently specifically distinct.

86

51. Machairopus minutus, G. 0. Sars, n. sp.

(PI. L).

Si>i'rific C/M/wr /</>-. Femalf. Form of body comparatively short and
stout, with the anterior division broad and depressed, the posterior abruptly much
narrower. Cephalic segment about the length of the 3 succeeding ones combined,
and, seen dorsally, almost crescent-like, being evenly rounded in front and having
the lateral corner much expanded. Penultimate segment nearly transversely trun-
cated behind. Last segment of metasome very small, but wholly uncovered. Uro-
some scarcely attaining half the length of the anterior division, and gradually
tapering behind, lateral edges of the segments finely ciliated. Caudal rami about
as long as they are broad, and transversely truncated at the tip, innermost but
one of the apical set;c not nearly attaining twice the length of the urosome.
Anterior antennae rather slender and gradually attenuated, 2nd joint but little
longer than the 3rd, 4th about half the length of the latter, terminal part half
as long as the proximal part, with the last joint shorter than the other 4 com-
bined. Posterior antennae with the outer ramus about half the length of the inner,
and 4-articulate. First pair of legs of almost exactly the same structure as in the
type species. Last pair of legs with the basal joint somewhat lamellar, and pro-
duced at the end inside to a conical process carrying 2 plumose setae, terminal
joint scarcely longer than the basal one. and of oval form, narrowly truncated
at the tip, and provided with 3 apical and one lateral plumose seta.

Body of whitish colour, with a broad rosy band across the cephalic seg-
ment, and another of the same colour across the anterior part of the urosome.

Length of adult female 0.65 mm.

/ii'innrl,'*. This is a much smaller species than that originally described
by Brady, the length of which is recorded to be almost twice as large (1.30 mm.).
In its external appearance this form looks very like some species of the genus
A///", especially 7. minor Scott, and at the first sight may be easily confounded
with that species. On a closer inspection, however, it is distinguished by the
comparatively broader and more depressed anterior division, and by the rather
different structure of the anterior antenna 1 . The colour also is rather characteristic.

Ori-tiiTi'itm. -I have occasionally found this interesting form in several
places on the west coast of Norway, for instance at Aalesund, Christiansund,
ll;ui'_ r '--imd ;ind Kopervik. It is a strictly littoral form, occurring close to the
shore among algae.

Distribution. Polar inlands north of Grinnell Land (2nd Fram Expedition).

87
Gen. 24. Idya, Philippi, 1843.

Syn: Thisbe,

Generic Characters. Body more or less distinctly depressed, with the
anterior and posterior divisions sharply defined. Cephalic segment of moderate
size and narrowly produced in front, rostral projection short and obtuse, not de-
fined at the base. Epimeral plates of the 3 succeeding segments rather broad.
lamellar, obtuse at the tips. Last segment of metasome very small. Urosome
moderately slender, with the genital segment in female more or less distinctly
divided in the middle, genital tubercles in male each armed with a strong
posteriorly-pointing spine. Caudal rami generally short but, with some of the
apical setae much elongated. Eye normal. Anterior antennae more or less slender
and attenuated, 8-articulate, sensory filament of 4th joint very fully developed;
those of male slightly transformed, subprehensile. Posterior antennae with the
outer ramus well developed, 4-articulate. Anterior lip rather prominent, tapering
distally, terminal edge minutely denticulate. Mandibles with the masticatory part
rather slender and coarsely dentated at the tip, palp of comparatively simple
structure, though distinctly biramous. Maxillae with the palp only very slightly
lobular, epipodal lobe wholly absent. Both pairs of maxillipeds uncinate at the
tip, the anterior ones biarticulate, with a single very slender lateral lobe at the
junction of the two joints, the posterior ones distinctly 3-articulate, with a single
slender apical claw. First pair of legs with both rami 3-articulate, but rather
unequal in size and structure, the inner one much longer than the outer and
having the penultimate joint more or less prolonged, the last very small with 2
comparatively short claws; outer ramus with the spine of the 1st joint, as a rule,
much elongated, that of 2nd joint issuing from near the end, last joint provided
at the inner corner with 2 slender ciliated setae, and along the obliquely trun-
cated end with 4 outward-curving spines gradually increasing in length, and each,
like that of the 2nd joint, penicillate at the tip, or clothed on one edge with a
limited number of long cilia. Natatory legs comparatively largely developed, with
the rami nearly equal and the joints rather broad sublamellar; middle joint of inner
ramus in all pairs with 2 natatory setae. Last pair of legs more or less slender,
extended laterally, proximal joint only very slightly expanded inside, distal joint
generally narrow, linear; those in male not very different, though somewhat
smaller than in female.

Eemarks. This genus was established in the year 1843 by Philippi, to
include a Mediterranean species, I. barbigem Phil. Prof. Lilljeborg did not recog-
nise the Philippian genus, and established a new genus, Thixbe. for the reception

__88

of the form, previously described by Baird as Canthocamptus f'tir<-tns, a species
which is undoubtedly closely allied to, if not identical with, that recorded by
Philippi. Boeck was the first to call attention to this fact, and therefore restored
the Philippiun genus, which is now generally accepted. The genus is chielly
characterised by the comparatively simple structure of the oral parts, and by the
peculiar penicillate appearance of some of the spines issuing from the outer ramus
of the 1st pair of legs. It seems to comprise numerous species, which, however,
are so closely, related that they were not recognized as such by earlier carcino-
logists, but only as accidental varieties of the same species. To Dr. Tli. Scott
is due the statement by a careful anatomical examination, that these supposed
varieties in reality ought to be considered as distinct species, since their distinc-
tive characters have proved to be perfectly constant and independent of external
conditions. Dr. Scott has described 6 different species from the Scottish coast,
and 1 have myself been enabled to distinguish no less than 9 Norwegian species,
to be described below. The genus seems to be represented in all parts of the
oceans, and I have even found one or two species of this genus in the Cas-
pian Sea.

52. Idya furcata (Baird).

(PI. LI, PI. LII, fig. 1).

*, lininl, Brit. Entoinostraca. p. 210. PI. XXV, figs. 1 & 2, PI. XXX.
figs. 1 6.

''. Syn : I'li/n liiii-biyrrd, Philippi.

S/,rri/!<- ('liai-iirln:*. Fcni'ilr. Body moderately slender, with the anterior
division, seen dorsally, regularly oval or elliptical in outline, being evenly nar-
rowed both in front and behind. Urosome about half the length of the anterior
division and gradually tapered behind, genital segment very distinctly divided in
the middle. Caudal rami scarcely as long as the anal segment, outermost and
innermost apical set;e comparatively short, the latter somewhat angularly bent
at the base. Anterior anteim;e of moderate length and gradually tapered
distally. 2nd joint exceeding the 3rd in length, 4th joint shorter than either of
thc>e joins, terminal part about twice the length of the 4th joint. First pair of
h-gs with the outer ramus extending somewhat beyond the 1st joint of the inner,
L ; nd joint of the latter but slightly attenuated, last joint very small, with the
apical daws comparatively short and somewhat unequal, the one quite smooth,
the other penicillate at the tip. Last pair of legs with the inner expansion of

89

the proximal joint broadly rounded and carrying 3 setee, the middle one rather
slender, the other 2 very small, distal joint moderately elongated, sublinear in
form, with 5 slender setse, 3 of which issue from the tip, 2 from the outer edge
close to the end. Ovisac oval in form and generally very large, containing
numerous ova or embryos, its colour varying, according to the development, from
dark green to light yellowish red.

Male much smaller than female and of more slender form. Anterior an-
tenme more strongly built and distinctly geniculate. Last pair of legs of smaller
size than in female, one of the apical setse of the distal joint transformed to a
strong ciliated spine.

Body in female of a whitish colour, and more or less distinctly banded
transversally with a clear crimson ; ovarial tubes generally of a very dark colour.

Average length of adult female about 1 mm., of male 0.65 mm.; maximum
length ,of deep-water variety 1.50 mm.

Remarks. The specific name furcata assigned to this form by Baird.
refers to the strong development of the sensory filament issuing from the 4th
joint of the anterior antennas, which gives these organs the appearance of being
bifurcate at the end. This is, however, a feature common to all the species of
this genus. Whether the lily a barbie/era of Philippi in reality belongs to this spe-
cies or to some nearly-allied form, it is impossible at present to decide with per-
fect certainty; but as the present species is by far the commonest, there is good
reason for believing the two to be identical. In any case, however, the specific
name proposed by Baird must be retained as the older one. Besides the usual
littoral form, another form of considerably larger size is occasionally met with
in somewhat greater depths among decaying alga3. I have carefully compared
this form with the usual one, but have failed to detect any perceptible anatomical
difference.

Occurrence. This is perhaps the commonest and most widely distributed
of all our Harpacticoida, being found everywhere along the Norwegian coast, and
generally in great numbers, close to the shore among alga?. It is also very often
left in tidal pools together with other littoral forms. It is a very active little
creature, swimming about with great speed, now and then affixing itself to the
fronds of the algae or to the walls of the vessel in which it is being observed.

Distribution. Arctic Ocean, widely distributed, British Isles, Kattegat,
coast of France, Mediterranean, the Red Sea (A. Scott), New Zealand (Brady),
Chatham Islands (the present author).

12 Crustacea.

_ 9n

53. Idya minor, Scott.

O'l. Ml. Bg. -2).
/.///</ mi,,",-. Tli. S.-..U. in AimaN nf Sr,,ttisli Nat. Hist. iSMti. p. _!:.'S. I'l. IV. li--. 11 17.

Clti-it<-trr..- /''i-niuli'. Form of body on the whole considerably
shorter and stouter than in ./. ftin-tiln. with tin.- anterior division only very slightly
contracted behind, and the e])iincral plates more closely contiguous. Urosome
about halt' the length of the anterior division, and of nearly uniform width through-
out. Caudal rami very short, with the apical setae less elongated than in the
other species. Anterior antennae comparatively shorter than in 1. furrnfn. with
the 'Jnd and Mrd joints of about equal length. First pair of legs with the outer
minus scarcely extending beyond the 1st joint of the inner; 2nd joint of the
latter comparatively longer and more attenuated than in /. fmrata. Last pair
of legs with the inner expansion of the proximal joint narrowly rounded at the
tip. the outermost of the '> marginal seta3 considerably longer than the innermost;
distal joint subspatulate in form, gradually widening towards the end.

Colour whitish.

Length of adult female 0.57 mm.

Remarks. This is the smallest of the Norwegian species of I<lt/<i, and
thus fully deserves the name given to it by Th. Scott. The si/e of the Norwe-
gian specimen^ is even inferior to that recorded by Scott, which gives the length
of the animal as 0.7<) mm. It is, moreover, easily distinguished from Itli/a
f'nrrntft by the much shorter and more compact form of body, in which respect
it somewhat resembles the above-described Mii<-li(iin>]><t* Hthntttt*.

()<-rn-rn<-<: I have found this form occasionally in several places on the
west coast of Norway in comparatively shallow water, on a muddy bottom.

i. Scottish coast (Scott), Fran/ Josef Land (same author).

54. Idya ensifera (Fischer).

il'l. Ull. liir. 1).

Y7,,\/,, ensifera, s.-i,. Fi>ri,,.r in Ai.liitmil. d. K. Bayer. Aka.1. Vol. VI 1 1. p. titis. n. ill.

tins. 6770.

Specific < 'liiti-iirt, />-. ]<'<I,KI/>. (u-neral form of body about as in /. f'ur-
i. l'i-o>oiin-. houever, comparatively more slender, exceeding half the length
of the anterior division. Caudal rami very short, apical set;e. on the Other hand
much elongated, the outermost and innermost ones being much longer than in
/. /ttrcil'i. Anterior antenn.-e likeuise more elongated than in that sprcics. and

91

inure richly setiferous, 3rd joint rather narrow and somewhat exceeding in length
the 2nd. First pair of legs with the inner ramus fully twice as long as the outer,
2nd joint comparatively slender, apical claws of about the same structure as in the
2 preceding species. Natatory legs with the rami more slender than in /. /'///-
cata, the 3rd joint of the outer ramus in 4th pair being especially of a very nar-
row form. Last pair of legs with the inner expansion of the proximal joint nar-
rowly rounded and having all 3 marginal setae well developed, distal joint exceed-
ingly slender and elongated, narrow linear in form, and having one of the lateral
setae at some distance from the others.

Body of a whitish colour, faintly tinged with light red.

Length of adult female about 1 mm.

Remarks. I think I am right in considering the above-described form to
be identical with that recorded by Seb. Fischer as Thisbe ensifera. In size and
external appearance it is very like 1. furcata, and was also adduced to that
species by Prof. Brady. On a closer examination, however, it is found to differ
in the more elongated and more richly setiferous anterior antennae, and especi-
ally in the exceedingly slender form of the distal joint of the last pair of legs.
In the structure of the other legs also, and in the relative length of the caudal
setae, well-marked differences from 1. farcata are found to exist.

Occurrence. This form is by no means unfrequent off the Norwegian
coast. In the upper part of the Christiania Fjord, for instance, it occurs rather
plentifully in depths ranging from 6 to 20 fathoms; and I have also met with it
in several localities on the west coast, and even in Fimnark.

Distribution. Madeira (Fischer).

55. Idya tenera, G. 0. Sars, n. sp.

(PI. LIII, fig. 2).

Specific Characters. Female. Form of body very slender, with the an-
terior division, seen dorsally, oblong fusiform in outline, and the epimeral plates
separated by deep lateral incisions. Urosome about half the length of the anterior
division, and gradually tapering distally. Caudal rami very short, apical setce
somewhat less elongated than in I. ensifera. Anterior antennae moderately slender,
with the 3rd joint fully as long as the 2nd. First pair of legs with the inner
ramus comparatively shorter than in I. ensifera and more resembling that in I.
fnrcata, 2nd .joint, however, scarcely longer than the 1st. Last pair of legs with

92

the proximal joint only very slightly expanded inside, but carrying tin- .'> usual
marginal setae; distal joint rather slender, resembling in form that in /. /'//rc'itn.

Body of a whitish colour, without any distinct pigmentary ornament.

Length of adult female 0.78 mm.

/,'-///"//>. -This new species is nearly allied to 1. fuinitn. hut is of much
-mailer si/e and more slender form of body. In the relative length of the joints
of the anterior antenna 1 , it somewhat resembles /. ensifera; but the structure of
the 1st and last pairs of legs is rather different.

Occurrence. I have found this form in considerable abundance in some
localities on the west coast of Norway, for instance at Her0, Kopervik and Buk-
keii. and occasionally also off the Finmark coast. It is a sublittoral form, gener-
ally oc( urring near the shores in campany with /. /'/// C'I/K. ovigerous females of
both species being at once distinguished by their very different size.

5H. Idya longieornis, Scott.

(I'l. I, IV. fig. I i.

/////,/ /.i,/./,', ../-,/iV 'I'll. Bcott, iii Ann. ,< .M:ii:. .!' X:it. Hi-t. S.T. i. V>1. XV. p. Itil. I']. XVII.

flgs. lo 17.

r*. Fcmtilr. Korm of body rather slender, with the
anterior division, seen dorsally, ova! fusiform in outline, epimeral plates com-
paratively broad, subcontiguous, except the last pair. Urosome about half the
length of the anterior division and rather narrow, only slightly tapering distally.
< 'audal mini -hurt, apical seta?, however, much elongated. Anterior antennae ex-
ceedinglj slender and attenuated, with the :$rd and 4th joints unusually narrow
and elongated, both being of about e<|iial length, and somewhat exceeding that of
the 2nd joint: terminal part extremely narrow, and scarcely longer than the 4th
joint. First pair of le^s of inconsiderable si/e in proportion to the body, and
somewhat re>embling in structure those in /. /'nrciitn, the outer ramus extending
considerably he\ind the 1st joint of the inner. Last pair of le^s \\ ith the prox-
imal joint only vi-ry slightly expanded inside, the innei-most of the marginal setae
comparatively slmrt : distal joint very narrow, linear in form, being nearly (i times
as IOIIL' aa it is broad.

Mody of a whitish colour, with a slight bluish ureen tinge, and exhibiting
at the posterior part of the cephalic segment a short transverse band of a dark
\io|;ieroiis hue. and another similar band across the middle of the urosome: an-
ti-rior antenii;i- with a small patch of the same colour near the end.

Length of adult female 1 .."id mm.

93

Remarks. This is one of the larger species of Iili/a, the length being
recorded by Scott as even reaching 1.70 mm. The Norwegian specimens ,-uv not
quite as large, but otherwise agree perfectly with the description given by that
author. The species is especially characterised by the peculiar appearance of the
anterior antennae in the female, these appendages being quite unusually slender,
and particularly distinguished by the great length and narrowness of the 3rd and
4th joints.

Occurrence. I took this form, many years ago, at Christiansund and
Sauesund, close to the shore among algse; and even at that time I recognized it
as a distinct species, to which the provisional name /. nobilis was given. It seems
to be rather local in its occurrence, as no specimens have been found in the
large material collected during recent years in other parts of the coast.

Distribution. Scottish coast (Scott).

57. Idya elegantula, G. 0. Sars, n. sp.

(PI. LIV, fig. 2).

Specific Characters. Female. Body moderately slender, with the anterior
division, seen dorsally, oval in outline, being only slightly narrowed behind. Cephalic
segment very large, considerably exceeding in length that of all the free segments
of metasome combined, and gradually tapering in front to an obtuse point. Epi-
meral plates closely contiguous, and rounded at the tips. Urosome about half the
length of the anterior division, and slightly attenuated distally, with the genital
segment imperfectly divided in the middle. Caudal rami somewhat more produced
than in the 4 preceding species, but otherwise of a very similar appearance.
Anterior antennae very slender, resembling in structure those in /. longicornis,
but with the 3rd joint comparatively more elongated, exceeding in length
both the preceding and succeeding joints. First pair of legs with both rami
unusually slender, the inner one being, as usual, the longer, and having the 2nd
joint much longer than the 1st and greatly attenuated distally; apical spines of
outer ramus more slender than in any of the 4 preceding species. Last pair of
legs with the distal joint much elongated, sublinear in form, one of the marginal
setse placed at rather a long distance from the others. Ovisac containing only a
very limited number of comparatively large ova.

Body of a pale yellow colour, with several interrupted transverse bands
of a clear chestnut brown across both the anterior and posterior divisions

Length of adult female 0.80 mm.

94

,-*. -In the structure of the anterior antenna 1 this form somewhat
resembles /. l<i<jie<>nii*. It is, however, of much inferior si/e, and moreover dif-
fers conspicuously from that species in the peculiarly slender form of the 1st pair
of legs, in which respect it agrees more closely with the succeeding species. /.
<li-<irilix. Scott.

OiTitri-i-iire. Only a solitary female specimen of this beautiful species has
as yet come under my notice. It was taken, many years ago, at Christiansund
in a depth of 50 60 fathoms. The figure of the animal here given is a copy
of the coloured drawing made from the specimen when still alive.

58. Idya graeilis, Scott.

(I'l. LV, litr. 1).

i/rai-ilis. Th. Semi. Additions i,, the Fauna of the Firth \' Forth: IHlh Annual Ur|n>rt <>t'
the Fishery Board for Scotland, p. 171, 1*1. IV, liys. lo-lM.

Body comparatively slender, attenuated he-
hind. Cephalic segment rather broad, and somewhat exceeding in length that of
the 3 succeeding segments combined. Epimeral plates broadly rounded, subconti-
guous. Urosome considerably exceeding half the length of the anterior division,
and gradually tapering distally. Caudal rami unusually produced, being nearly
twice as long as they are broad, outermost and innermost of the apical seta)
comparatively short, seta of the outer edge somewhat remote from the apex.
Anterior antennas of moderate length, 2nd joint the largest, 3rd and 4th of about
equal length. First pair of legs with both rami very slender, somewhat re-
sembling in structure those in I. clrj/fnttiiln. inner ramus, as usual, the longer,
with the 2nd joint nearly twice as long as the 1st and much attenuated distally;
apical claws of this ramus comparatively short. Terminal spines of outer ramus,
on the other hand, exceedingly slender, each with only a few cilia at the tip.
Last pair of legs with the proximal joint comparatively small, distal joint, how-
ever, rather elongated, oblong fusiform in shape, with one of the marginal setae
considerably remote from the others, issuing nearly from the middle of the
outer edge.

M"l' not much smaller than female, and exhibiting the usual sexual dif-
ferences. In the 2nd pair of legs, moreover, the seta of the 1st joint of the
inner ramus is peculiarly modified, being transformed into a strong spine minutely
hidentate at the tip.

i 'olour nut yet determined.

Length of adult female about 1 mm.

95

Remarks. This form, recently described by Th. Scott, may, on a close
examination, be at once distinguished from any of the other species of My a by
the unusual production of the caudal rami. The structure of the 1st and last
pair of legs, moreover, is rather characteristic.

Occurrence. On examining the preserved material collected during the
last 2 years from the sublittoral region off the west coast of Norway, at Aale-
sund, Kopervik and Bukken, I have succeeded in finding several specimens, both
females and males, of this distinct species. It also occurs off the Finmark coast,
as proved by the examination of some samples taken by Mr. Nordgaard and
kindly forwarded to me.

Distribution. Scottish coast (Scott).

59. Idya angusta, G. 0. Sars, n. sp.

(PL LV, fig. 2).

Specific Characters. Female. Body exceedingly slender and elongated, with
the anterior division, seen dorsally, oblong in form. Cephalic segment exceeding
in length that of the 3 succeeding segments combined, and, as usual, conically
produced in front. Epimeral plates discontiguous, being separated by deep lateral
incisions. Urosome extremely narrow, cylindrical in form, and exceeding half the
length of the anterior division, genital segment distinctly divided in the middle.
Caudal rami comparatively short, apical setae, however, much elongated. Anterior
antennae slender, with the 3rd joint rather elongated, exceeding in length both
the preceding and succeeding joints. First pair of legs less slender than in the
2 preceding species, 2nd joint of inner ramus scarcely longer than the 1st, last
joint imperfectly defined and having the apical claws comparatively elongated and
subequal, both penicillate at the tip. Last pair of legs unusually small, distal
joint oval in form, being scarcely more than twice as long as it is broad, one of
the marginal setae attached to about the middle of the outer edge.

Colour not yet determined.

Length of adult female 0.87 mm.

Remarks. In the exceedingly slender and narrow form of the body, this
species bears a strong resemblance to a form described by Mr. A. Scott from
the Irish Sea as I. elongata. It differs very essentially, however, in the much
more slender and elongated anterior antennae, these appendages in the Irish form
being, on the contrary, unusually short and compact. The structure of the 1st
and last pairs of legs also seems, to judge from the figures given, to be rather
different in the 2 species.

_ 96

Occurrence. Only a solitary female specimen of this form has as yet
come under my notice. It was taken, many years ago. at Her0, west coast of
Norway, the depth not heing recorded.

61 >. Idya finmarehiea, G. 0. Sars. n. sp.

(I'l. LYI).

c C1i(tr<tftr/-s. /'"rn/nle. Body of comparatively robust form and
much depressed, with the anterior division, seen dorsally, broadly oval in form.
Cephalic segment considerably expanded, and about the length of the 3 succeed-
ing segments combined. Epimeral plates broad and rounded at the tips, sub-
contiguous. Urosome about half the length of the anterior division, and gradually
tapering distally. genital segment very distinctly divided in the middle, anal seg-
ment extremely small. Caudal rami somewhat produced, though comparatively
shorter than in 7. <jnicUix, innermost and outermost of the apical setae compara-
tively short, seta of outer edge placed about in the middle. Anterior- antenna?
rather short and stout, not nearly attaining the length of the cephalic segment,
2nd joint the largest, though scarcely longer than the 3rd. Posterior antennae and
oral parts, as also the natatory legs, of exactly the same structure as in I. j'ur-
ciitn. First pair of legs, however, rather different, with the rami comparatively
more slender, the inner one being, as usual, the longer and having the 2nd joint
of greater length than the 1st, though scaicely at all attenuated distally; last
joint very small, but well defined, and carrying on the tip 2 remarkably slender
subequal claws, both perfectly smooth. Terminal spines of outer ramus rather
slender, each witli only a few cilia at the tip. Last pair of legs rather fully
developed, basal joint moderately expanded inside, with 2 of the marginal set;e
very small, terminal joint large, oblong fusiform in shape and densely hairy, one
of the marginal seta.- remote from the others, and attached somewhat beyond the
middle of the outer edge. Ovisac large.

( 'olour not yet determined.

Length of adult female 1.20 mm.

/.'< ///"//>. At first I believed this form to be the 1. <-ltttlt<i- of Scott, on
account of the peculiarly slender form of the :ipic;il claws of the inner ramus of
the 1st pair of leg-. Having recently, however, through the kindness of Th.
Scott, had the opportunity of examining one of his specimens. I find that these
2 forms are evidently specifically distinct the one from the other. 7. i-lnllin' is
a much ^mailer and more slender specie-. ;iml has the .-interior antenna' consider-

97

ably more elongated than the Norwegian species. Well-marked differences also
seem to exist between the 2 species in the structure of the 1st and last pair

of legs.

Occurrence. Several specimens of this interesting form were found in
some samples kindly forwarded to me by Mr. Nordgaard, who took them of!'
the Finmark coast, partly at Repvaag, partly at Mehavn. Farther south this
species does not seem to occur, being in all probability a true arctic form.

Gen. 25. IdyOpSlS, G. 0. Sars, n.

Generic Characters. Body short and depressed, somewhat resembling in
form that in Idya, the anterior division being more or less expanded, the poste-
rior abruptly much narrower. Rostral projection small, not defined at the base.
Anterior antennae not much elongated, 8-articulate, sensory filament of 4th joint
much smaller than in Idya. Posterior antennae with the outer ramus well devel-
oped, 3- or 4-articulate. Anterior lip of usual form. Mandibles with the palp
rather fully developed, biramous. Maxilla? of quite normal structure, the epipodal
lobe being well defined. Anterior maxillipeds of rather compact form, with all
the lateral lobes distinctly developed, the outermost armed with one or two strong
claws; terminal part distinct. 3-articulate, setiferous. Posterior maxillipeds well
developed, 3-articulate, carrying on the tip 3 strong claws. First pair of legs
with the outer ramus much shorter than the inner, and somewhat resembling that

in Idt/a, the lateral and apical spines being provided along the outer part of
one edge with slender cilia, inner ramus distinctly 3-articulate, with the 1st joint
rather large, the other 2 much smaller and subequal in size, last joint carrying
2 slender claws on the tip, and inside 2 short seise. Natatory legs resembling
in structure those in Iflija, middle joint of inner ramus, however, in the posterior
pair with only a single seta. Last pair of legs, as in Idya, extended laterally,
distal joint narrow and elongated.

Remarks. This new genus somewhat resembles Itlya, as regards the
general form and composition of the body, but differs rather essentially in some
of the anatomical details, especially in the structure of the oral parts,
defined species of this genus occur off the Norwegian coast.

13

98

61. Idyopsis dilatata, ft. 0. Sars. n. sp.

(PI. LVH, fig. 1).

Anterior division of body much dilated,
with the cephalic segment very largely expanded, and ahout twice as long as the
3 succeeding segments combined, lateral edges boldly curved, front bluntly
rounded. Kpimeral plates rather narrow, acutangular at the tips. Last segment
of nietasome extremely small, but wholly exposed. Urosome comparatively short,
m it attaining halt' the length of the anterior division, genital segment rather large
and expanded, its lateral edges minutely indented in the middle and h'nely cili-
ated. Caudal rami about as long as they are broad, and obtusely truncated at
the tip: apical setje of moderate length. Eye well developed. Anterior antenna 1
comparatively slender, though not nearly attaining the length of the cephalic seg-
ment. 2nd joint much the largest, terminal part considerably shorter than the last
2 joints of the proximal part combined. Posterior antenna) with the first 2 joints
imperfectly defined, outer ramus 3 -articulate. First pair of legs with the outer
ramus scarcely exceeding in length the 1st joint of the inner, and having all 3
joints of about equal si/e. Last pair of legs very narrow, with the proximal joint
scarcely at all expanded inside, distal joint narrow fusiform in outline, with one
of the marginal setae attached to about the middle of the outer edge. Ovisac
rounded, containing only a limited number of comparatively large ova.

Body of a pale yellowish colour, with a slight rosy tinge; ovarial tubes
reddish brown, forming on each side, within the cephalic segment, a remarkably
large ca-cal dilatation.

Length of adult female about half a millimetre (0.48 mm.).

/'< murk*. This form may be easily recognised by the remarkably broad
and flattened cephalic segment, a character which has given rise to the specific
name here proposed.

On-urrcnrf. Some few female specimens of this species have been found
at different times oft' the west coast of Norway (Skjerjehavn, Sauesund) in depths
ranging from 10 to .'50 fathoms.

. Polar Islands north of (irinnell Land (2nd Fram Kxped.).

99

62. Idyopsis pusilla, G. 0. Sars, n. sp.

(PL LVII, fig. 2).

Specific Characters. Female. Anterior division of body less expanded
than in the preceding species. Cephalic segment moderately dilated, and not
nearly twice as long as the 3 succeeding segments combined. Epimeral plates
comparatively broader and less extant, especially those of the last pair, which
are obtuse at the tip. Urosome, as in the preceding species, rather short, genital
segment less expanded, but more deeply indented on each side in the middle.
Eye inconspicuous. Anterior antennse comparatively shorter and stouter than in
I. clilatata, with the terminal part about the length of the 2 preceding joints
combined. Posterior antennae with the first 2 joints distinctly defined, outer ramus
comparatively short, but distinctly 4-articulate. Anterior maxillipeds remarkably
large and robust, claw of outermost lobe coarsely spinulose on the one edge.
First pair of legs closely resembling in structure those in I. clilatata, but with
the outer ramus somewhat longer than the 1st joint of the inner. Last pair of
legs with the proximal joint quite short, but produced inside to a narrow lingui-
form lamellar expansion, carrying on the tip 3 setse, the middle one rather elon-
gated; distal joint narrow fusiform in outline, seta of outer edge placed close to
the apex.

Colour whitish.

Length of adult female 0.43 mm.

Remark*. Though nearly allied to the preceding species, and evidently
congeneric with it, this form is at once distinguished by the less expanded an-
terior division of the body, as also by the comparatively shorter and stouter an-
terior antennse. The last pair of legs, also, are rather different in the 2 species.

Occurrence. Only 2 female specimens of this form have hitherto come
under my notice. They were found, many years ago, at Mager0, south of the
entrance to the Trondhjem Fjord, in a depth of about 40 fathoms.

Gen. 26. Idyella, Gr. 0. Sars, n.

Generic Characters. General form of body rather resembling that in
Idya, the 2 chief divisions being very sharply defined from one another.
terior antennse comparatively short, and angularly bent at the b;>

1 1 III

1'o-terior ;int'iiii:i i comparatively -lender, .'{-articulate, with the outer ramus short,
Inarticulate. Mandibles, maxilla- and anterior maxillipeds resembling in structure
those part- ii: /</'/<///.-/>. 1'o-terior maxilliped-. ho\\e\vr. much more slender, and
having a very movable articulation between tin- tirst '2 joint-, last juint carrying
an elongated daw accompanied liy ~1 or .'! -lender seta'. Kiist pair of legs with
the outer ramii- about as in /<///"/<>/>. inner ramus. however, only composed of '1
join!- \er\ niovahlx articulated together, the lust one carrying outside 3 short
-eta' and at the tip 2 very slender claws. Natatory legs with the ranii rather
-lender and -uheipial in length, middle joint of inner ramus carrying in the 2
anterior pair- ~1 seta', in the posterior pair 1. Last pair of legs slender and. as
in /'///"//*/> . extended laterally.

Remarks. -This uenus is nearly allied to Jtli/<iji*is, but differs in sonic
particular-, e-pedally as regards the structure of the posterior maxillipeds and
that of the 1st pair of legs. Of this genus also. ~2 well-defined species have been
found off the Norwegian coast.

''>. Idyella pallidula, (^. <>. Sars. n. p.

(PI. I.VIII, Ii-. 1 ).

s/nfir Characters. Female. Anterior division of body rather broad and

d-pri'--ed : seen dor-ally, oval fusiform in outline, with the greatest width some-
what hchind the middle. Cephalic segment very large, about twice as long as
the :; -m-cerdiiig -egments cnmbined. and gradually tapering anteriorly, front
conically produced. Kpimeral plates Bub-COntigUOUS, obtuse at the ti}is. Last
-lament of meta-ome very small. t'rosome not attaining half the length of the
anterior dhision. genital segment produced on each side, somewhat in front of
the middle, to an ol>lii|iiel\ posteriorly-pointing triangular lobe; Jnd segment
-imple. Caudal rami short, with the usual number of -eta', one of them issuing
from the middle of the outer edge, the L' middle apical seta' rather slender. Kye
wholly ab-ent. Anterior antenna' scarcely attaining half the length of the cephalic
-euim-nt and clothed with comparatively short Bet, L'nd joint the largest, terminal
part about the length of the '2 preceding joint- combined. Posterior maxillipeds
uith the midille joint xcai-cely at all dilated, siiblinear in form. First pair of
legs with the outer ramus much curved and somewhat exceeding half the length
of the inner, proximal joint of the latter rather broad, lamellar, with a strong
pliimo-.' seta in the middle of the inner cd.ue. distal joint much narrower than
the proximal one, and more than half its length. Last pair of h -- \er\ narrou.

11)1

proximal joint scarcely at all expanded inside, distal joint somewhat longer, with
one of the marginal seta3 attached to the outer edge in front of the middle.

Colour pale whitish, with a slight yellowish grey tinge.

Length of adult female about half a millimetre.

Remark*. This form may be easily recognised by the conically produced
frontal part, the peculiar form of the genital segment, and the total absence of
any visual organ.

Occurrence. I have only met with this peculiar Copepod in the upper
part of the Christiania Fjord, where some few female specimens were found in a
depth of about 30 fathoms, muddy bottom.

64. Idyella exigua, G-. O. Sars, n. sp.

(PI. LVIIT. fio. 2).

Specific Characters. Female. Anterior division of body somewhat less
expanded than in the preceding species, with the cephalic segment of inferior
size, not attaining twice the length of the 3 succeeding segments combined, and
more evenly contracted anteriorly, front narrowly rounded. Urosome somewhat
exceeding half the length of the anterior division, genital segment exhibiting on
each side 2 successive triangular lobes separated by a deep median incision ; 2nd
segment with the posterior corners conically produced. Caudal rami about as in
I. paUiilnla. but with the seta of the outer edge obsolete. Eye very conspicuous
even in preserved specimens, exhibiting 4 dark-coloured lenticular bodies arranged
in pairs in the usual place. Anterior antennae comparatively more robust than
in the preceding species, with the terminal part shorter, not attaining the length
of the 2 preceding joints combined. Posterior maxillipeds with the 2nd joint
conspicuously dilated beyond the middle. First pair of legs resembling in struc-
ture those in 1. pallidula, but with the proximal joint of the inner ramus less
broad and fully twice as long as the distal one. Last pair of legs less slender,
proximal joint produced at the end inside to a narrow conical projection carrying
2 slender setse; distal joint densely hairy, with one of the setse issuing from the
lower face in front of the middle. Ovisac rounded, only containing a limited
number of comparatively large ova.

Colour not yet determined.

Length of adult female 0.44 mm.

Remarks. This form is unquestionably congeneric with the preceding
one, as it exhibits the same characteristic structure of the posterior maxillipeds and

102

<>!' the 1-t pair of legs. It may, however, at once be distinguished from that
vj>rrie> by the very distinctly develo})cd eye, and also by the characteristic form
of the genital segment.

Ore//, )> i ice. On examining more closely some samples taken last summer
at Hukken. in the lower part of the Stavanger Fjord, just below a steep hill. I
Mieeeeded in finding several specimens of this small Cope-pod. Among them was
alo a male specimen, which exhibited sexual differences from the female quite
analogous to those found in the genus l<li/.

Fam. 10. Thalestridae.

i-tt. Body of rather variable form, in some cases much depressed,
in others almost cylindrical or even compressed laterally, the 2 chief divisions,
however, never being so sharply defined from each other as in the Idyidce.
K\e. as a rule, well developed, in some cases of rather complex structure.
Anterior antenrue not much elongated, and generally composed of 8 or 9 articu-
lations; those in male distinctly geniculate. Posterior antennae with the first 2
joints imperfectly defined, outer ranius comparatively small. Oral parts on the
whole normal; posterior maxillipeds terminating in a more or less strong clawed
hand. First pair of legs with both rami, as a rule, prehensile, armed at the tip
with unguiform spines. Natatory legs with both rami 3-articulate, the outer one
the longer; inner ramiis of 2nd pair of legs in male more or less transformed.
Last pair of legs foliaceous, not extended laterally, and much larger in female
than in male, covering the ovisac more or less entirely. The latter always single.
I,': nun /,.-. -This is perhaps the most extensive of all the Harpacticoid
families, comprising, as it does, even in the restriction here adopted, numerous
genera and species. The family to which it bears the closest relationship, is
unquestionably that of the l)n>*n<-c'i<ln', to be treated of farther on. the chief dist-
inction between the two being the duplieitv or non-duplicity of the ovisac.

103

Gen. 27. ThaleStriS, Glaus, 1863.

Generic Characters. Body robust, more or less curved ventrally, with
very thick and tough integuments. Cephalic segment large and somewhat com-
pressed in front, with the epimeral parts deflexed and more or less deep, in-
cluding between them most of the oral parts ; rostral projection short and thick,
deflexed, not detined at the base. Epimeral plates of the 3 succeeding segments
very thin and deflexed. Last segment of metasome not much narrower than the
the others, though with the epimeral plates less fully developed. Urosome in
female 4-articulate, with the genital segment more or less expanded and exhibiting
only slight traces of a subdivision; that of male distinctly 5-articulate. Caudal
rami with the apical setae, as a rule, very unequally developed. Eye large, in
some cases combined with lenticular thickenings of the integument. Anterior an-
tennae (in female) 9-articulate, 4th joint with the usual sensory filament. Posterior
antenna with the terminal joint rather coarse, and armed with strong claw-like
spines and geniculated setae; outer ramus comparatively small, biarticulate. Man-
dibles thickly incrusted, with the cutting edge coarsely dentate, palp well devel-
oped, biramous, with the basal part more or less expanded distally. Maxillae
with all parts well developed. Anterior maxillipeds short and compact, with a
strong claw at the outermost of the lateral lobes. Posterior maxillipeds very
powerful, hand more or less strongly dilated, terminal claw strong and curved.
First pair of legs with both rami 3-articulate and rather slender, subequal in
length, middle joint of outer ramus much elongated, last 2 joints of inner one
short, number of apical claws on the inner ramus 2, on the outer 2 or 3. Second
pair of legs with the middle joint of inner ramus carrying 2 natatory setae, in
male confluent with the last joint, and armed outside with one or 2 deflexed
spines. Last pair of legs in female generally very large, with both joints folia-
ceous, the proximal one forming a broad lamellar expansion inside.

Remarks. This genus, established by Claus, is here taken in a much
more limited sense than has been done by that author and by most other carcinolo-
gists. In the restriction here adopted, it is chiefly characterised by the compara-
tively robust body (which generally exhibits a more or less pronounced ventral
curvature), the unusually thick and tough integuments, and the nature of the ros-
trum, which forms the immediate continuation of the cephalic shield, without
being defined from it by any suture or indentation at the base. There are 5
species belonging to the Norwegian fauna, which will be described below.

65. Thalestris longimana, daus.

(I'l. MX i IA).
Cl;m<. Di.- I'rfilebenden <'npi'|ii>.|i-ii. p. 1:1O. PI. XVIII. figs. 1 11.

Sjicri/ii- Chnrnrtri-*. l-"<'nmi< . liody very robust, with the back more or
less curved, and the segments of the anterior division sub-imbricate dorsally.
i 'ephalic ^cgment of very large si/e. and conspicuously compressed in its an-
terior part, the epimeral parts being very deep and arcuate. Rostral projection
short and blunt at the tip. JJrosome scarcely exceeding half the length of the
anterior division, and having the segments very sharply defined; genital segment
large and broad, seen dorsally, quadrangular in form, with the lateral parts lamel-
larly expanded; last segment very small, often almost wholly concealed by the
preceding segment. Caudal rami comparatively short, not much longer than they
are broad, and transversely truncated at the tip. each with a short seta at about
the middle of the outer edge, innermost but one of the apical setne much coarser
than the others, and about equal in length to the urosome. Eye large and very
conspicuous in living specimens. Anterior antennae scarcely exceeding half the
length of the cephalic segment, 2nd joint much the largest, about equal in length
to the -2 succeeding joints combined, terminal part of about the same length.
Anterior maxillipeds less compact than in the other species, with the claw of the
outermost lateral lobe smaller, terminal part distinctly developed, narrow cylin-
drical and inarticulate. Posterior maxillipeds exceedingly large and powerful, with
the hand considerably dilated, and forming a prominent angular projection below,
defining the palm in front, the latter deeply concaved in the middle, with the edge
densely spinulose throughout; terminal claw very strong and provided at the ba-e
inside with a slender spine. First pair of legs with both rami of equal length,
the outer one somewhat narrower than the inner, and angularly bent near the
ha^e. each ramu> armed at the tip with '2 unequal claws finely denticulate along
the eoncase edge, and accompanied inside by a small, hair-like bristle: terminal
joint of outer ramiis. moreover, exhibiting on the outer ed^e -2 minute spinules.
L.-i>t pair of legs exceedingly large, extending beyond the limits of the genital
-eminent: distal joint oblong oval in form, and evenly rounded at the tip: inner
expansion of proximal joint extending as far as the distal one. and somewhat
narrowed in its outer part: marginal seta 1 of both joints comparatively short
and Dimple.

Mulr >ome\shat smaller than female, and easily recognised by the more
strongly built and geniculate anterior antennae and the distinctly ">-articulate uro-
Inner ramii^ of _?nd pair of legs transformed in the usual manner. Last

105 .

pair of legs rather unlike those in female, and much smaller, distal joint narrow
oblong in form, with some of the marginal seise, spiniform, inner expansion of
proximal joint quite short, scarcely extending to the middle of the distal joint,
and provided with only 3 marginal setse, the outermost one spiniform. Genital
tubercles with 3 subequal setse.

Body of a golden yellow colour, more or less variegated with a dark
reddish brown pigment, especially along the ventral face and at the posterior
edges of the segments.

Length of adult female 1.40 mm., of male 1.20 mm.

Remarks. This form I regard as the type of the genus Thalestris, in the
restriction here adopted. It is one of our larger Harpacticoids, and is moreover
easily recognizable by its very robust form and the exceedingly powerfully devel-
oped posterior maxillipecls, which somewhat resemble those in Harpacticus clu'Ufi'r.

Occurrence. I have found this form not unfrequently in several localities
of the west coast of Norway, as far as to the Trondhjem Fjord, in moderate
depths among algse. It moves in the usual somewhat jumping manner. When
disturbed, it curves its body more or less sharply ventrally, and remains in this
attitude quite motionless for some time.

Distribution. British Isles (Brady), Heligoland (Clans), coast of France
(Canu).

66. Thalestris gibba (Kr0yen.

(PL LXI).
Harpacticus gibbus, Kvayer, in "Gaimard" Voyage en Scandiiiavie, PI. 43, tigs. 2. a p.

Syn: Thalestris polaris, Scott.

Specific Characters. Female. Body somewhat more slender than in the
preceding species, otherwise of a very similar aspect, with the back more or less
gibbously curved, and the integuments very thick and tough. Cephalic segment,
as in T. longimana, of considerable size and somewhat compressed anteriorly,
with the epinieral parts rather deep and curved in the middle; rostral projection
more prominent than in that species, and acutangular at the tip. Posterior edges
of all the segments minutely crenulated. Urosome considerably exceeding half
the length of the anterior division, and having the segments very sharply defined,
the genital one of moderate size and less expanded than in T. longimana; last
segment very small. Caudal rami unusually produced, being nearly 3 times as
long as they are broad, apical setse, on the other hand, much shorter than in

14 Crustacea.

106

tin; >aid species, the innermost but one scarcely attaining half the length of the
uro>ome. seta of the outer edge placed near the tip. and. like the outermost of
the apical seta 1 , reduced to a small, knob-like spine. Anterior antenna 1 with the
2nd joint somewhat shorter than in T. luiuj'niiiout, terminal part nearly half the
length of the proximal part. Posterior maxillipeds less powerfully developed than
in that species, with the hand less dilated and the palm only slightly concaved,
being defined in front by an obtuse angle. First pair of legs resembling in struc-
ture those in T. loiiiiumnni. but with the rami somewhat narrower, apical claws
scarcely at all denticulate. Last pair of legs well developed, though not nearly
as large as in T. Imii/iniana. extending only somewhat beyond the middle of the
genital segment, distal joint rounded oval in form and somewhat exserted at the
tip. inner expansion of the proximal joint broadly rounded at the end, and scarcely
extending as far as the distal joint; marginal setoe of both joints comparatively
more elongated, some of them spiniform and minutely ciliated.

Mult- differing from the female in a manner analogous to that in the
preceding species. Last pair of legs rather similar, but having the distal joint
more attenuated towards the end, and the inner expansion of the proximal joint
>till shorter, with the 3 marginal set3 very unequal, the middle one being much
elongated, whereas the outermost one is much reduced in si/e.

< 'olour of body, except the dorsal face of the cephalic segment, very dark-
bluish grey or almost black.

Length of adult female 1.50 mm.

l\< -murks. This form was first figured (but not described) by Kroyer in
the above-quoted work as Hnrficficus yllilms. It was subsequently described by
Th. Scott as a new species under the name of Thalcstri* /><>l<ir/*, he not having
been aware of the fairly recognizable figures given of this species by Kroyer. It
is nearly allied to T. /n>/<iiii/>ui<i. though easily distinguishable by its more slender
form, and especially hy the much more produced caudal rami. \Ylirn alive, it
i- aUo rero-ni/ed at once by the very dark colour of its body.

<><->-ii rri-ncr. I have found this form in several localities on the west coa>t
of Norway, and northwards along the whole Finmark coast as far as Vads0. In
some places it oceiirrt-d in great numbers on a muddy bottom covered with de-
eaying alga-, the depth being about 20 fathoms.

/)i*lrilittli'>ii. Fran/. -losef Land (Scott I.

107

67. Thalestris rufoviolaeens, claus.

(PI. LXIl).
TJialcstris rufoviolaeens, Claus. Die Copepodenfauna von Nizzn, p. 83. PL IV, figs. 18 2^.

Specific. Characters. Female. Body comparatively short and stout, some-
what resembling in form that in T. longimana. Cephalic segment very large,
with the epimeral parts deep and greatly curved in the middle; rostral projection
somewhat prominent and acute at the tip. Urosome comparatively short, scarcely
attaining half the length of the anterior division, genital segment large and rather
broad in its anterior part; last segment, as usual, very small. Caudal rami ex-
tremely short, considerably broader than they are long, and densely clothed
at the end with delicate filaments, the 2 larger of the apical setse rather slender.
and issuing close together from a knob-like projection at the inner corner
below, outermost seta rather elongated and distant from the others. Anterior
antennae of the usual structure, 2nd joint rather large and tumid, terminal part
nearly half the length of the proximal part. Posterior maxillipeds of moderate
size, resembling those in T. gibba. First pair of legs likewise rather similar,
though with the inner ramus somewhat shorter than the outer. Last pair of legs
of quite extraordinary size, extending even beyond the 2nd caudal segment, both
joints broad, foliaceous, and ornamented on the surface with a peculiar, as it
were bipinnate marking; marginal setse of both joints comparatively small and
simple. Ovisac small, rounded, and almost wholly concealed by the lamellae of
the last pair of legs.

Male exhibiting the usual sexual differences from the female.

Body of a whitish colour, variegated with irregular patches, partly of a
reddish, partly of a deep violaceous hue.

Length of adult female 0.90 mm.

Remarks. The above-described form is unquestionably identical with that
originally recorded by Glaus as T. rufoviolaeens. On the other hand the form so
named by Brady does not belong to this species, but apparently to the next. The
most characteristic features of the present form are the peculiar structure of the
caudal rami and the extraordinary size of the last pair of legs in the female.

Occurrence. Only 2 or 3 specimens of this form have hitherto come
under my notice. They were taken, many years ago, at Hero, west coast of Nor-
way, in moderate depths among alga?.

Distribution. Mediterranean at Nice (Claus).

108

'. Thalestris brunnea, G. 0. Sars, n. s

(I'l. I, Mil).
Syn: 7 /ml si, -is ,-itf',ii-iultii;-iix. \\\-,\<\\ (not Clans 1 .

dm/ -urii'i^. Fcniitlc. Body very robust and somewhat depressed

throughout its whole length; seen dorsally. slightly tapering behind. Integu-
ments coarsely chitinized. Cephalic segment large and broad, occupying ratlin-
more than half the anterior division, epimeral parts less deep than in the 3 pre-
ceding species; rostral projection strong, detiexed, acutangular at the tip. Posterior
dge of this and the 3 succeeding segments minutely crenulated. Urosome some-
what exceeding half the length of the anterior division, and slightly narrowed
behind, genital segment almost twice as broad as it is long, and, like the 2 suc-
ding segments, having the lateral edges minutely ciliated; penultimate segment
forming a triangular prominence behind, arching over the small last segment.
Caudal rami short and broad, densely spinulose at the edges and with the apical
setae of inconsiderable length, the innermost but one being about half as long as
the urosome. Eye very large and conspicuous in the living animal. Antennae
differing but little in structure from those in the other species. Mandibular palp.
however, somewhat less fully developed, the basal part being only very slightly

xpanded distally. Anterior maxillipeds remarkably short and compact, with the
innermost lateral lobe rather large, and divided into 2 diverging lappets, each

arrying a thickish plumose seta, claw of outermost lobe very strong; terminal
part rudimentary. Posterior maxillipeds likewise of an unusually compact struc-
ture. basal joint very short, hand much curved outside, palmar edge straight and
imperfectly defined in front, terminal claw strong and much curved at the tip.
Kir-t pair of legs with the outer ramus somewhat longer than the inner, and
-iirerly narrower, terminal joint armed with 3 unequal claws finely denticulated
on the one edne. and moreover, at the inner corner, with a rather long curved
-eta, and outside the claws with a small spinule; inner ramus. as usual, carrying
on the tip '1 claws, which are likewise finely denticulate and somewhat less un-
equal than in the preceding species. Last pair of legs of moderate size, extend-
ing somewhat beyond the middle of the genital segment, distal joint broadly oval
in form and obtuse at the tip. inner expansion of proximal joint rather large.
with 2 of the marginal setae considerably produced and spiniform.

Colour of body, except the dorsal face of the cephalic segment, a deep
brown, posterior edges of the 1 segments still darker.
Length of adidt female about 1 millimetre.

Jdyidas.

Copepoda

Harpacticoida.

Fl.XUX.

\' )

autogr. p sam athe lonqicauda, Phil. " rsk Uth 9 r - Offfcin -

Jdyidas.

Copepoda

Harpacticoida.

FLL.

a\U* h - ./;

/fr (*' .?.y- '//

m I \
- ,

G.O. Sars autogr.

M L j. r> n n Norsk Lithqr. Officin.

Macnairopus minuius, G.O.Sars.

Jdyid

ae.

Copepoda

Harpacticoida.

PI LL.

GO. Sars autogr.

Jd_ya furcata , (Baird)

Norsk Lithgr. Officin.

Jdyidae

Copepoda

Harpacticoida.

PI.UI

G.O. Sars autogr.

I.Jdya Furcata , (continued )
2.Jdya minor, Scott

Norsk Lithgr. Offic'm.

Jdyidaa

Copepoda

Harpacticoida.

PI. LIE.

('J

"*- -\ Ti///^'

G.O.Sars eutogr.

I. Jdya ensifera (Fischer.)
2.Jdya tenera, G.O.Sars

Norsk Lithgr. Officin

Jdyidae.

Copepoda

Harpacticoida.

PI.UV

G. O.Sars eutoqr. i i i i ' r\ _u_

I Jdya longicopnis, Scott.
2 Jdya elegantula , 6. O.Sars

Norsk Li+hgr. OffTcin

Jdyidas

Copepoda

Harpacticoida.

PI. LV

G.O.Sars autogr , , ... o Norsk Lithqr. Offlcin

I. Jdya gracihs , Scott
2 Jdya angusta , G.O.Sars

Jdyidas.

Copepoda

Harpacticoida.

PI LVI.

6. 0.Sars autogr.

Jdya finmarchiQa , G.O. Sans

Norsk Lithgr. OffTcin

Jdyidaa.

Copepoda

Harpacticoida.

PL LVU

G.Q.Sars autogr.

I Jdyopsis dilalata, G.O.Sars
2.Jdyopsis pusilla, G.O.Sars

Norsk Lithgp. Officin

Jdyidae.

Copepoda

Harpacticoida.

PLLVIII.

'.'.v-',..
;

6. 0.Sars autogr.

Udyella pallidula G.O.Sars
2.Jdyella exigua, G.O.Sars

Norsk Lithgr. Officin

Thalestridae

Copepoda

Harpacticoida.

P1.L1X

G.O.Sars autogr.

Thalestris longimana, CIs.

Norsk Lithcjr. Offlcin

Thalestndae.

Copepoda

Harpacticoida.

PL LX.

G.O.Sars autogr.

Thalestris longimana, CIs,
(continued)

Norsk Lithgr. Dfflcin

Thalestridae

Copepoda

Harpacticoida.

PL LIT

6.0. Sars eutogr

Thalesiris gibba (Kroyer)

Norsk Lilhgr. Officin

Thalestridae.

Copepoda

Harpacticoida.

PI. LXIl.

e.O.Sars

Thalestris rufoviolacens, CIs.

Norsk Lithqr. Offioin

Thalestridse.

Copepoda

Harpacticoida.

PI. LXI1I.

6. 0.Sars autogr. Norsk Lithgr. OffTcin

Thalestris brunnea, G.O.Sars

Thalestridae,

Copepoda

Harpacticoida.

PI. LXIV.

G.O.Sars autoqr. Norsk Lithgr. Offlcin

Thalestris purpurea, G.O.Sars

AN ACCOUNT

OF THE

CRUSTACEA

OF

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS IX & X

THALESTRHLE (continued)

WITH 16 AUTOGRAPHIC PLATES

BERGEN
PUBLISHED BY THE BERGEN MUSEUM

/ SOLD BY

ALB. CAMMEEMEYEE'S FOELAG, CHEISTIANIA

1905

109

Remarks. This form has been erroneously identified by Prof. Brady with
T. rufoviolacens of Glaus, from which it differs conspicuously both as regards the
general form of the body and some of the anatomical details. The figure of the
animal given by Brady is somewhat misshapen, apparently owing to a strong
pressure of the mounted specimen from which the drawing was made.

Occurrence. Some few female specimens of this form were found, many
years ago, off the west coast of Norway, at Molde and Christiansund.

Distribution. British Isles (Brady).

69. Thalestris purpurea, G. 0. Sars, n. sp.

(PI. LXIV).

Specific Characters. Female. General form of body very similar to that
in T. brunnea, being conspicuously depressed throughout. Cephalic segment, how-
ever, seen dorsally, more regularly rounded in front, and having the lateral cor-
ners more produced. Rostral projection abruptly recurved, with the tip bluntly
rounded. Penultimate segment of urosome forming a thin expansion behind, arch-
ing over the last segment and divided into 4 regularly rounded lobules. Caudal
rami of much the same structure as in T. brunnea. Eye still larger than in that
species, and on each side applied to a distinct lenticular thickening of the integu-
ment. Antennae, mandibles, maxillae and anterior maxillipeds almost exactly as
in T. brunnea. Posterior maxillipeds, however, comparatively less powerfully
developed, hand less curved outside, and not having the palm at all defined in
front. First pair of legs resembling in structure those in T. brunnea, though
having the apical claws of both rami somewhat more elongated. Last pair of
legs likewise very similar, distal joint, however, more oblong in form, and the
marginal spines of proximal joint less elongated.

Colour of body a deep crimson, dorsal face of cephalic segment some-
what lighter.

Length of adult female 0.96 mm.

Remarks. This form is very closely allied to T. brunnea, and indeed
preserved specimens of the two may be easily confounded. In the living state,
however, the present form is at once recognized by the deep crimson colour of its
body. On a closer comparison, some well-marked differences in the anatomical
details are also found to exist, proving these 2 forms to be in reality specifically
distinct. The shape of the rostrum is rather different, for instance, and the pos-
terior maxillipeds are somewhat dissimilar in size. The regularly 4-lobate lamellar

15 Crustacea.

110

expansion of the penultimate caudal segment is moreover very characteristic of
tin- present species.

Urnirri in-' . 1 have only met with this form very occasionally, though
in several places, on the west coast of Norway. It occurred in moderate depths,
among alga} and Hydroida.

Gen. 28. ParathaleStriS, Unuly & Robertson, 1873.

Generic ('li<tr<-t<'>\<. -Body more slender than in Tltnl<'*fi-i$, generally
cylindrical in form, or somewhat compressed laterally, never depressed, nor ex-
liihiting the marked curvature of the anterior division characteristic of that genus.
('phalic segment of moderate size, with the epimeral parts less deep than in
'/'//'//<>///' x; rostrum forming a short triangular plate movably articulated to the
cephalic shield. Urosome more elongated than in the said genus, with none of the
segments lamellarly expanded. Caudal rami generally short, but with the apical
seta} much elongated. Eye well developed. Antenna} and oral parts on the whole
resembling in structure those appendages in Thiilt'dnx. First pair of legs likewise
rather similar, with both rami more or less slender and subequal in length, 2
of the apical claws of the outer one generally well developed. Inner ramus of
i ; nd pair of legs in male transformed in a similar manner to that in Tlil<'*lri*,
its middle joint in female carrying 2 natatory setae, that of the 2 succeeding pairs
only a single such seta. Last pair of legs of moderate size, with both joints lamel-
lar, those in female, as usual, much larger than in male. Ovisac large, pyriform.

Hi -murk*. This genus was established in the year 1873 by Messrs. Brady
and Robertson, to include a species previously recorded by Norman as Thnlr*h-i*
Cluiisi. It was, however, subsequently withdrawn by Prof. Brady, who did not
find sufficient evidence for the generic separation of the said species. In sub-
dividing the old genus 'I'hnlt'slrix. however, into several nearly-allied genera. I
find it. convenient to restore the present genus, which, in addition to the above-
named species, also comprises a number of other related forms, some of which
\\ill be described below. The genus is chiefly distinguished from '/'hli'*fri* (in
tin- restri'-tion here adopted) by the more slender form of the body, the inferior
Size ot the cephalic segment, and especially by tin- nature of the rostrum, which
is sharply defined from the cephalic shield, and to a certain extent mobile. To
the Norwegian fauna belong I species lelerahle to this genus.

Ill

70. Parathalestris Clausi (Norman).

(PI. LXV & LXVI).
Thalestris Clausi, Norman, Brit. Assoc. Eeport 1868, p. 297.

4 Specific, Characters. Female. Body moderately slender and conspicuously
compressed, being rather strongly built, with the integuments highly chitinized.
Cephalic segment about the length of the 4 succeeding segments combined, epime-
ral parts only slightly arched; rostrum very short and blunt at the tip. Urosome
scarcely half as long as the anterior division, and without any distinct lateral
rows of spinules on the segments, genital segment about the length of the remaining
3 segments combined. Caudal rami quadrangular and but slightly divergent,
apical setae of moderate length. Anterior antenna comparatively short, 9-arti-
culate, distal part about half the length of the proximal one. Posterior antennae
rather robust, with the distal joint considerably expanded at the end, spines of
the anterior edge very strong and distinctly denticulate. Posterior maxillipeds
powerfully developed, with the hand very broad, dactylus strong and curved. 1st
pair of legs comparatively strongly built, with the outer ramus a little shorter
than the inner but somewhat stouter, terminal joint lamellarly expanded and
having the 2 innermost claws very strong and, like the much smaller 3rd one,
finely pectinate on the concave edge; apical claws of inner ramus likewise dis-
tinctly pectinate and somewhat unequal, the inner one being the longer. Last
pair of legs rather broad, foliaceous, distal joint rounded oval in form, inner
expansion of proximal joint broadly triangular and extending as far as the distal
one, marginal setae of both joints comparatively short.

Male somewhat smaller than female, and exhibiting the usual sexual dif-
ferences. Last pair of legs much smaller than in female, distal joint short and
broad, cordate, witli the marginal setae more or less spiniform, inner expansion
of proximal joint scarcely extending beyond the middle of the distal one, and
carrying 3 marginal setae, the outermost shorter than the others and spiniform.

Colour generally golden yellow.

Length of adult female 1.05 mm.

Remarks. This form, first described by Norman, is closely allied to P.
harpacticoides of Glaus, but is of larger size, and on the whole of more robust build,
both as regards the body itself and its appendages.

Occurrence. -I have met with this form rather abundantly along the whole
Norwegian coast, from the Christiania Fjord to Vadso, in the littoral zone among
algae, and, like other littoral forms, it is not infrequently left in tidal pools.

Distribution. British Isles (Brady), coast of France (Canu).

112

71. Parathalestris harpacticoides (Glaus).

(PI. LXVII).
Tlialestris harpactoides, Claus, Die freilebenden Copepoden, p. 133, PI. XIX, figs. 2 11.

Specific r//'//v/r/,rs. F< j /nnl<'. Very like the preceding species,* hut of
smaller size and on the whole less strongly built. Cephalic segment comparatively
larger, considerably exceeding in length the 4 succeeding segments combined;
rostrum somewhat more prominent. Urosome exceeding half the length of the
anterior division and having the segments more sharply marked off from each
other, all, except the last provided on each side with a very conspicuous oblique
row of spinules. Caudal rami about as in P. Clausi. Anterior antennae com-
paratively more slender, with the distal part exceeding half the length of the
proximal one. Posterior maxillipeds far less powerful, with the hand oblong oval
in form and the dactylus more slender. 1st pair of legs of a structure very
similar to that in P. Clauni, though having the outer ramus comparatively nar-
rower and scarcely shorter than the inner. Last pair of legs with the distal joint
less broad, oblong oval in form, inner expansion of proximal joint likewise nar-
rower and extending scarcely as far as the distal joint; marginal setae of both
joints more elongated than in P. Clausi.

.!/'//< exhibiting similar differences from the female to those in P. Clttnxi.
Last pair of legs, however, conspicuously differing in shape from those in the
male of that species, the distal joint being much narrower and scarcely at all di-
lated at the base, inner expansion of proximal joint very slight, with 3 marginal
setse, none of which are spiniform, innermost seta the shortest.

Colour generally dark olivaceous.

Length of adult female 0.73 mm.

7iV>mo7-N. As stated above, this form is closely allied to P. Clni<*i, ex-
hibiting a very similar structure of the 1st pair of legs. On a closer comparison,
however, some well-marked differences in the structural details are found to exist,
proving these two forms to be in reality specifically distinct, though unquestionably
congeneric. An easily recognizable external character is also found in the oblique
rows of spinules on the sides of the caudal segments, of which scarcely any trace
i> found in /'. Cl>ni*i.

Occurrence. -This is also a rather common form, being found along the
whole south and \\rst coasts of Norway in the littoral and sub-littoral regions
among alga;. In the upper part of the Christiania Fjord this form is by far the
most frequent.

l>/.--ti-ilmtitj)i. Heligoland (Claus), British Isles (Brady), coast of Bohuslan
(Coll, deve).

113

72. Parathalestris hibernica (Brady & Rob.).

(PI. LXVIII).

Thalcstris hibernica, Brady Kobertson, in Ann. & Mag. Nat. Hist., ser. 4, Vol. XII. p. 135,

PI. VIII, figs. 1719.

Specific Characters. Female. Body conspicuously compressed and very
slender and elongated, with the integuments rather thin and pellucid. Cephalic
segment scarcely exceeding in length the 4 succeeding segments combined, epimeral
parts much curved in the middle, rostrum of moderate size. Urosome about
half the length of the anterior division and having the segments quite smooth.
Caudal rami short quadrangular, with the outermost of the apical setae consider-
ably thickened at the base. Eye very large and conspicuous in the living animal.
Anterior antennae rather slender, with the distal part exceeding half the length
of the proximal one. Posterior antennae less strongly built than in the 2 pre-
ceding species. Mandibular palp with the inner expansion of the basal part rather
narrow and prominent, outer ramus small, with only a single apical seta. Pos-
terior maxillipeds powerfully developed, with the hand large, sub-crescentic in
shape, and irregularly angular, palmar edge deeply concaved and defined in front
by a distinct projecting corner, dactylus very strong and curved. 1st pair of
legs much feebler in structure than in the 2 preceding species, both rami slender
and tapering distally, the outer one a little shorter than the inner, with the ter-
minal joint scarcely at all expanded, claws slender and quite smooth, the inner-
most one very much elongated, equalling in length the 2 preceding joints com-
bined; apical claws of inner ramus very unequal, the inner one much elongated,
the outer very small. Last pair of legs considerably smaller than in the 2 pre-
ceding species, distal joint oval in form, inner expansion of proximal joint rather
broad and extending considerably beyond the distal one. Ovisac generally very
large, pyriform.

Male with the last pair of legs, as usual, less fully developed than in
female, distal joint rather small and having only 5 marginal setae, inner expansion
of proximal joint not nearly extending as far as the distal one, and carrying 3
unequal setse.

Body semipellucid, of a light greenish hue and generally filled with clear
oil-bubbles.

Length of adult female 1.14 mm.

Remarks. This is a very distinct and easily recognizable form, being
especially distinguished by its slender and elongated body, as also by the struc-
ture of the posterior maxillipeds, and the 1st and last pairs of legs.

114

'. I have met with this form occasionally in several places of
the west coast of Norway, for instance at Kopervik, Aalesund and Christiansund,
in the- littoral region among alga.'. It is, however, not nearly so common as the
2 preceding species.

Di*h'ilinti<t. British Isles (Brady).

73. Parathalestris Jacksoni (Scott).

(PI.

i, Th. Scott, Report, on marine ami I'resh water Crustacea from Franz Josef
Land, Linn. Boc. Jcurn. Vol. XXVJ1. p. 109, PI. 8, figs. 39.

-jfic Cltdractrrx. 7<V/m//r. Body elongated, but rather strongly built,
with highly chitinized integuments and the segments very sharply marked off from
each other. Cephalic segment about the length of the 4 succeeding segments
combined, epimeral parts evenly curved, posterior edge, like that of the 3 suc-
ceeding segments, minutely crenulated; rostrum short and blunt, well defined at
the base, tip minutely bifid. Urosome slender tapering distally. genital segment
very distinctly divided in the middle. Caudal rami unusually prolonged, being
more than twice as long as they are broad and slightly attenuated distally, apical
setae normal. Anterior antennae of moderate length, with the distal part scarcely
half as long as the proximal one. Anterior maxillipeds rather compact, with the
claw of the outermost lobe unusually short. Posterior maxillipeds powerfully de-
veloped, hand large, oval fusiform, with the palmar edge slightly concaved. 1st
pair of legs moderately strong, outer ramus fully as long as the inner, 2 of the
apical claws very strong and curved; apical claws of inner ramus very unequal,
the inner one more than 3 times as long as the outer. Last pair of legs well
developed, foliaceous, distal joint very large, ovate, inner expansion of proximal
joint scarcely extending beyond the middle of the distal one, marginal setie of
modi-rate length.

Mnlr exhibiting the usual sexual differences.

Colour yellowish brown, somewhat darker at the end of the segments,
dorsal face of cephalic segment of a lighter hue.

Length of adult female 2.20 nun.

Remarks. --This form was first described by Th. ISc.ott from Kran/ Josef
Land. It is one of the largest Harpactiroida, and by its strongly built body,
tlir sharp demarcation of the segments, and the unusually prolonged caudal rami,
somewhat resembles certain species of the genus Tlt<i/<'.--tri* (in the restriction here

115

adopted), for instance, T, gibla Kr0yer. It is however a true Parafhalestris as
proved both by the structure of the rostrum and that of the several appendages.

Occurrence. Off the Finmark coast this form is by no means rare.
I found it, for instance, many years ago in considerable abundance at Vadso;
and in some samples taken by Mr. Nordgaard at Repvaag (Porsanger Fjord),
and kindly sent to me for examination, it was also rather common. Though
undoubtedly a true arctic form, it also occurs occasionally far out of the arctic
region, for instance in the outer part of the Trondhjem Fjord, at Bejan, and in
the Storfjord, inside Aalesund. A single specimen of this form was even taken
as far south as Grimstad, off the south coast of Norway.

Distribution. Franz Josef Land (Scott), Polar Islands north of Grinnell
Land (2nd Fram Exped.).

Gen. PhyllOthaleStriS, G. O. Sars, n.

Generic Characters. Body somewhat compressed in front, more flattened
behind, with the cephalic segment very large and deep. Rostrum abruptly de-
flexed and apparently immobile, though defined from the cephalic segment by a
well market! suture. Epimeral plates of the 3 succeeding segments rather fully
developed. Urosome of moderate length, with the genital segment in female very
large and flattened. Eye large and of rather complicated structure. Anterior an-
tennce slender, 9-articulate; posterior ones less strongly built than in Parathalestris,
outer ramus biarticulate. Oral parts on the whole normal. 1st pair of legs of
a structure similar to that in Thalestris. Natatory legs likewise rather similar,
though having the terminal spine of the outer ramus shorter. Last pair of legs
in female of enormous size, foliaceous, wholly obtecting the ovisac below.

Remarl-s. The type of this new genus is the Thalestris mysis of Glaus,
a form which in some characters, and more particularly in the enormous deve-
lopment of the last pair of legs in the female, differs conspicuously from the other
Thalcstr'ulce, so that it ought more properly to be generically separated. We do
not ;at, present know any other form . that can be associated with it in the
same genus.

116

74. Phyllothalestris mysis (Glaus).

(PI. LXX & LXXT).
Tliakstris mi/sis, Die freilebenden Copepoden, p. 130, PI. XVIII, figs. 1216.

Specific C'lixructcrs. Female. Body moderately slender, with the anterior
division slightly vaulted dorsally. Integuments rather thin, and exhibiting a finely
sqitamous sculpture. Cephalic segment considerably exceeding in length the 4
succeeding segments combined, epimeral parts thin and pellucid, much curved
in the middle, and almost wholly comprising between them the oral parts ; rostrum
very strong, acuminate, and pointing straight down. Epimeral plates of the 3
succeeding segments closely contiguous and acutangular behind. Last segment of
metasome scarcely narrower than the preceding one, but much less deep. Uro-
some exceeding half the length of the anterior division, and having the genital
segment very large and expanded, clypeiform. Caudal rami short, quadrangular,
with the 2 middle apical setae much elongated and somewhat divergent, the inner
one about twice the length of the urosome. Eye very large and conspicuous in
the living animal, with 2 successive pairs of lenticular bodies, anterior extremity,
seen laterally, drawn out into 2 diverging lobules. Anterior antennae with the
distal part scarcely half as long as the proximal one. Posterior maxillipeds rather
slender, with the hand narrow fusiform, palmar edge straight, outer edge angular
in the middle, dactylus slender and elongated. 1st pair of legs with the rami
slender and attenuated, the outer one somewhat longer than the inner, both having
mie of the apical claws strongly developed, falciform. Last pair of legs extending
almost to the end of the penultimate caudal segment, both joints greatly expanded,
foliaceous, the distal one oval or elliptical in form, with 6 short marginal seta?
densely crowded together at the tip, the outermost but one very coarse, spiniform;
inner expansion of proximal joint extending as far as the distal joint and car-
rying 5 short marginal setae, 4 of which are attached close together at the bluntly
rounded tip, the 5th at a considerable distance from these on the inner edge.

Mtil<- of smaller si/e than female, and exhibiting the usual sexual dif-
ferences. Last pair of legs rather dissimilar and of much inferior size, distal
joint narrow oval in shape, and provided with only 5 marginal setae; inner expan-
sion of proximal joint very slight, with only 2 unequal spines at the tip.

Body generally of a fine rosy or light carneous colour, with the tip of
the urosome together with the caudal setae very dark.

Length of adult female 1.40 mm.

KemarJes.Th\s is an easily recognizable form and indeed one of our
I'mc^t Elarpacticoida, distinguishing itself both by its comparatively large si/e and
the general form of the body, as also by its peculiar colour.

117

Occurrence. I have met with this beautiful form in several places both
on the south and west coasts of Norway, as also in the Trondhjem Fjord, but
nowhere in any considerable number. It is generally found in depths ranging
from 6 to 20 fathoms among Laminarise and other algse. The movements of the
animal are particularly rapid and graceful.

Distribution. British Isles (Brady), Mediterranean (Glaus), Gulf of Suez
(A. Scott), Ceylon (same author).

Gen. 30. Hall thai 6StriS, G. 0. Sars, n.

Generic Characters. -Body elongated, subcylindrical in form, with no sharp
demarcation between the 2 chief divisions. Cephalic segment comparatively small
and somewhat depressed, rostrum short, but uell defined at the base. Epimeral
plates poorly developed. Urosome very large and massive, with the caudal rami
unusually prolonged and divergent. Eye normal. Anterior antennre of usual
structure, 9-articulate. Posterior antennae with the outer ramus rather narrow,
biarticulate. Oral parts on the whole normal; posterior maxillipeds, however,
unusually compact. 1st pair of legs resembling in structure those in Thalestris.
Natatory legs likewise of a very similar structure. Last pair of legs of moderate
size, with the distal joint the more prominent.

Remarks. This new genus is founded upon the peculiar form first recorded
by Kroyer as Harpacticus Groni, and subsequently described by Brady under the
name of Thalestris serrulata. According to the structure of the 1st pair of legs,
this form is indeed more nearly related to Thalestris than to Harpacticus, and
unquestionably belongs to the family Thalestridcc. It cannot however properly be
referred to the genus Thalestris in the restriction here adopted, and it also dif-
fers very markedly from the other Thalestridse, both in its whole external ap-
pearance and more particularly in its habits, it being one of the few Harpac-
ticoida, which leads a true pelagic life. The generic name here proposed refers
to this latter peculiarity.

16 Crustacea.

118

75. Halithalestris Croni (Ki-r.yor).

(I'l. LXX1I).
I'l-'nii, KroyiT, ill Caimanl's ..Ynyage en Scandinavie". /uol., I'l. 4:5. ti^s. H, a n.

Byn: Tlmlestris s<rrnl<itti, Hrady.

Body very slender and elongated, and of
a peculiar smooth appearance, recalling that found in the forms belonging to the
family IJ-ttHaxanttilti'. Cephalic segment scarcely exceeding in length the 3 suc-
ceeding ones combined, and tapering anteriorly to an obtuse point, epimeral parts
but very slightly developed; rostrum short, somewhat cleflexed. Epimeral plates
of the 3 succeeding segments small, not covering laterally the basal parts of the
legs. Last segment of metasome scarcely narrower than the preceding one.
Urosome very greatly developed, exceeding the anterior division in length, and fully
equal to it in depth, segments fringed along the posterior edge ventrally with deli-
cate spinules, genital segment, as usual, the largest, though not attaining the
length of the 2 succeeding segments combined, last segment rather short and
deeply cleft at the end. Caudal rami very much elongated, almost attaining
half the length of the urosome and more or less divergent, outer edge with 3 or
4 slight serrations, tip obliquely truncated, apical seta; not much elongated, the
2 middle ones distinctly denticulated. Eye rather large and conspicuous in the
living animal. Anterior antenna) of moderate length, distal part somewhat ex-
ceeding half the length of the proximal one. Posterior maxillipeds of a very
compact structure, hand much dilated, almost semicircular in outline, palmar edge
straight and having inside a curved row of strong denticles, dactylus strong and
curved. 1st pair of legs with the outer ramiis fully as long as the inner, but
much narrower, 3 of the apical claws well developed and finely denticulated on
the concave edge; apical claws of inner ramus rather unequal, the inner one very
-tnmg and twice as long as the outer. Last pair of legs extending scarcely beyond
tlir middle of the genital segment, distal joint oval in form, with 2 of the mar-
ginal seta- rather elongated, inner expansion of proximal joint triangular, extending
somewhat beyond the middle of the distal one. the middle of the marginal setoc
much longer than the others. Ovisac very large.

Body semipellucid of a light greenish hue. and generally tilled with clear
oil-bubbles of various sixes.

Length of adult female 2.30 mm.

/A mnr/,". As stated above, this form was first figured (but not described)
by Krnver in the \\ell-kno\\n work by (nlaimard. and referred to the genus Httr-
The Tltttlrsh-ix *n'i 'iil'iln of Brady, described from a solitary male

119

specimen, is unquestionably identical with Kriiyer's species. It is one of our
largest Harpacticoida, and differs sconsiderably in its outward appearance from the
other Thalestridae, a fact which may no doubt be accounted for by its very dif-
ferent habits.

Occurrence. Only a very limited number of specimens of this peculiar
form, all of them females, have hitherto come under my notice. They were taken
partly off the Fimnurk coast, partly off the west coast of Norway, and in every
instance in the open sea at a considerable distance from the shore and near the
surface, together with other pelagic animals.

Distribution. British Isles (Brady), coast of Spitsbergen (Scott).

Gen. 31. RhynehOthaleStHS, G. 0. Sars, n.

Generic Characters. Body more or less robust, with the 2 chief divisions
rather sharply marked off from each other. Cephalic segment large and deep,
with the rostrum very prominent and very mobile. Urosome comparatively
short, with the anterior segments more or less expanded laterally. Caudal rami
short, but with the apical setae rather elongated. Eye well developed. Anterior
antennae of usual structure, 9-articulate. Posterior antennae with the proximal
part distinctly divided in the middle, outer ranius composed of 3 well-defined
joints. Oral parts normal and lather fully developed. 1st pair of legs of a
structure similar to that in Thalestris. Natatory legs with the spines of the outer
ramus coarsely denticulate, middle joint of inner ramus in all the pairs carrying
2 setae inside. Last pair of legs of moderate size, with the distal joint more
prominent than the proximal one.

Remarks. This new genus is chiefly characterised by the unusually sharp
demarcation of the 2 divisions of the body, and more particularly by the strong
development of the rostrum, a character which has given rise to the generic name
here proposed. In the structure of the several appendages also some well-marked
differences from the preceding genera are found to exist, especially as regards
the posterior antennae and the natatory le.gs. Two well-defined Norwegian species
are referable to this genus, both having been previously described as species of
the genus Thalestris.

120

76. Rhynehothalestris rufoeineta (Norman).

(PI. LXXIII \ LXXIV).

Tlialestris rufoeineta Norman (M. S.), in Hr;nl\'s IMon<><rraf of British Copepoda, Vol. 11, p. 125,

PI. LVII, figs. 19.

Spec'ifn- ( 'haracters. Female. Body somewliat robust, with the anterior
division evenly vaulted dorsally. Cephalic segment considerably exceeding in length
the 4 succeeding segments combined, epimeral parts evenly arched and rather deep;
rostrum very long and slightly curved, narrow linguiform in shape and acuminate
at the tip. Epimeral plates of the 3 succeeding segments rather large, acutan-
gular. Last segment of metasome considerably narrower than the preceding ones.
Urosome scarcely exceeding half the length of the anterior division, genital seg-
ment very large and expanded, sub-quadrangular in outline and distinctly divided
in the middle, posterior corners acutely produced and fringed with delicate spinules;
2nd segment likewise produced at the posterior corners, the 2 posterior segments
simple. Caudal rami quadrangular, broader than they are long, outermost of the
apical setse spiniform and scarcely half as long as the innermost, the 2 middle
setse very strong and elongated. Anterior antennae with the 1st joint unusually
prolonged, distal part not nearly attaining half the length of the proximal one.
Posterior antenna) with the outer ramus rather fully developed, middle joint much
shorter than the other 2. Posterior maxillipeds of moderate size, hand oblong
fusiform, with the outer edge sub-angular in the middle, inner straight, dactylus
slender. 1st pair of legs with the rami not very slender, the outer one a little
longer than the inner, with 2 of the apical claws well developed, apical claws of
inner ramus rather unequal. Natatory legs with the inner ramus shorter, but
broader, than the outer. Last pair of legs with the distal joint broadly oval in
form, inner expansion of proximal joint rather large, though not extending as far
as the distal one.

Mute with the inner ramus of both the 2nd and 3rd pairs of legs pecu-
liarly transformed, that of 2nd pair having the 2 outer joints coalesced and car-
rying on the tip a remarkably strong somewhat hamiform spine, that of 3rd pair
distinctly 3-articulate, with the last joint obliquely tapered and terminating in a
small lamella provided inside with a short Hexuose bristle, inner edge with a
regular series of 5 strong seta?. Last pair of legs, as usual, smaller than in
li-malc, with the inner expansion of the proximal joint shorter and provided with
only 3 spine-like setae.

Body of a clear yellowish hue, more or less distinctly banded with dark
reddish brown, sometimes, especially in male specimens, with the whole of the

121

1st free segment of the metasome and part of the 2nd dark red, anterior antennae
and basal part of the legs more or less tinged with chestnut brown.

Length of adult female slightly exceeding 1 mm.

'Remarks. This form was first detected by Norm and and was described
and figured under the MSname proposed by that author in Brady's well-known
Monograf. It is a very fine and easily recognizable species, being especially
distinguished by the very prominent rostrum, and in the living state also by the
beautiful colouring of the body.

Occurrence. I have met with this form occasionally in several places both
off the south and west coasts of Norway, as also in the outer part of the Trond-
hjem Fjord. It generally occurs in depths ranging from 6 to 20 fathoms among
Laminariae and other alga3.

Distribution. British Isles (Brady), coast of France (Canu).

77. Rhynchothalestris helgolandiea (Clans).

(PI. LXXV).
Thalestris liclyolandica, Glaus, Die freilebenden Copepoclen, p. 131, PI. XVII, fiys. 12 21.

Syn: Thalestris curticauda, Boeck.

Specific Characters. Female. Body comparatively short and stout, with
the anterior division somewhat depressed and very sharply marked off from the
posterior. Cephalic segment large and deep, with the epimeral parts abruptly
curved in front of the middle; rostrum somewhat smaller than in the preceding
species but of a very similar structure. Last segment of metasome abruptly much
narrower than the others, with the epimeral parts very small, acute. Urosome
unusually short, not nearly attaining half the length of the anterior division,
genital segment imperfectly divided in the middle, and much dilated, with the
lateral edges lamellar and strongly arcuate; posterior corners of this and the
succeeding segment slightly produced. Caudal rami very short, apical setse of
moderate length. Anterior antennae rather slender and of a similar structure to
that in R. rufocincta. Posterior antennae likewise rather similar, though having
the outer ramus less fully developed, with the terminal joint much shorter. Pos-
terior maxiilipeds unusually slender and elongated, with the hand rather narrow
and almost crescent-like in shape, dactylus very long, falciform. 1st pair of legs
much more slender than in the preceding species, with both rami rather narrow,
the outer one being the longer and having the terminal joint scarcely at all ex-
panded, one of the claws much longer than the others ; inner ramus likewise with

122

one of the apical claws very slender and elongated. Natatory legs with the rami
more slender than in R. rufocincta and nearly equal in length, middle joint of
inner ramus considerably produced at the outer corner, terminal joint of same
ramus rather elongated, with the outermost of the setse of the inner edge trans-
formed to a slender, coarsely denticulated spine. Last pair of legs with the distal
joint much elongated, narrow oblong in form, inner expansion of proximal joint
comparatively short, triangular, not nearly extending to the middle of the distal
joint. Ovisac comparatively small, rounded.

Male with the inner ramus of the 2nd pair of legs only very slightly
transformed. Last pair of legs with the distal joint considerably shorter than in
female and having the marginal setse spiniform; inner expansion of proximal joint
very slight, almost obsolete, with only 2 unequal marginal spines.

Body of a dark yellowish hue, with the posterior half of the anterior
division tinged, especially along the ventral face, with deep chocolate brown.

Length of adult female 0.74 mm.

Remarks. This form, first described by Glaus, may be easily recognized
by its short, stout body, and especially by the unusual shortness of the uro-
some. Moreover the very sharp demarcation between the 2 chief divisions of the
body is rather characteristic. Though differing rather conspicuously in some of
the anatomical details from R. rufocincta, it ought in my opinion to be referred
to the same geniu, since in other respects these 2 forms exhibit a perfect agree-
ment. The Thalcstrls curticauda of Boeck is unquestionably identical with
Claus's species.

Occurrence. I have taken this form occasionally off the south coast, more
frequently off the west coast, of Norway, in localities similar to those in which
R. rufocincta occurs.

Dittrilntlion. Heligoland (Claus), British Isles (Brady), Spitsbergen (Scott).
Fran/, Josef Land (same author).

. H2. Mierothalestris, G. o. Sars. n.

('liitritcliT*. Body slender, subcylindrical in form, with no very
obvious demarcation between the 2 divisions. Cephalic segment of moderate size,
rostrum small, but well defined. Epimeral plates poorly developed. Urosome
with none of the segments expanded laterally; caudal rami short. Anterior an-
tcnnte attenuated, 9-articulate. Posterior antenna) with the proximal joint not

123

divided, outer ramus small, Inarticulate. Oral parts on the whole less fully de-
veloped than in the preceding genera. 1st pair of legs with the rami very nar-
row and rather unequal, the inner one being much the longer and only composed
of 2 joints, the distal one very small; outer ramus with 3 well-developed claws
at the tip. Natatory legs slender, with the outer ramus much longer than the
inner, setae of the inner edge in both rami poorly developed; inner ramus of 3rd
pair of legs in male slightly transformed. Last pair of legs with the distal joint
much more prominent than the proximal one.

RemarTcs. This new genus is founded upon the form recorded by Glaus
as Thalestris forficida, a species which has proved to differ very markedly in several
respects from the other Thalestridse, not being referable to any of the genera
treated of in the preceding pages. We do not know at present with certainty
more than a single species, to be described below.

78. Microthalestris forficula (Glaus).

(I'l. LXXVI).
Thalestris forficula. Clans, Die freilebenden Copepoden, p. 131, PI. XVII, figs. 7 11.

Syn : TlKilcstrls karmensis, Boeck.
forficuloides, Scott.

Specific Characters. Female. Body narrow and elongated, seen dorsally,
almost linear in form, with rather thin and flexible integuments. Cephalic seg-
ment scarcely longer than the 3 succeeding ones combined, epimeral parts not
very deep, but evenly curved; rostrum very narrow, lanceolate. Epimeral plates
of the 3 succeeding segment small and rounded behind. Last segment of meta-
some scarcely narrower than the preceding ones. Urosome considerably exceeding
in length half the anterior division, and cylindric in form, with the segments densely
spinulose at the hind edge both ventrally and laterally, genital segment about
the length of the 2 succeeding ones combined, and distinctly divided in the mid-
dle. Caudal, rami very short, with the innermost but one of the apical setae
greatly developed, abruptly bent at the base, and about twice as long as the
urosome. Anterior antennae of moderate length and densely clothed with rather
long seta3, distal part considerably exceeding half the length of the proximal one.
Posterior antennae with the distal joint but slightly dilated, apical setae compara-
tively strong, spiniform, outer ramus small, with the 2 joints subequal in length.
Mandibular palp with the basal part only slightly expanded, outer ramus very
small. Posterior maxillipeds not very strong, hand oval in form, with the palmar

124

edge slightly convex and carrying in the middle a slender seta. 1st pair of legs
with the outer ramus much shorter than the inner, spine of the middle joint at-
tached close to the end, apical claws rather slender and gradually increasing in
length inwards, inner ramus with the proximal joint very narrow and elongated,
seta of the inner edge attached far in front of the middle, distal joint very small
and slightly expanded outside, apical claws of moderate size, the inner one twice
as long as the outer. Natatory legs with the terminal joint of the outer ramus
fully as long as the other 2 combined, and of narrow linear form, setae of the
inner edge in both rami much reduced in number. Last pair of legs with the
distal joint oblong hastate in form, densely spinulose on the edges, and provided
with 8 marginal setae, 3 of which issue from the inner edge; inner expansion of
proximal joint triangular and not nearly extending to the middle of the distal one.

Mule considerably smaller than female, and having the inner ramus of
3rd pair of legs (not that of 2nd pair) transformed, the terminal joint being pro-
duced at the tip to a long mucroniform spine. Last pair of legs very small,
with the distal joint subdivided into 2 or 3 successive segments.

Colour pale yellow.

Length of adult female 0.58 mm.

Remarks. This form was first described by Glaus from the Mediterranean,
at Messina, and has subsequently been found to occur also in the northern oceans.
The Thalestris Jcarmensis of Boeck is unquestionably identical with Claus's species,
and the form recorded by Th. Scott under the name of T. for/indoides has also
proved to be the same species. By its slender cylindrical and very flexible body
this form (lifters conspicuously from the other Thalestridae, and so far exhibits
a pronounced similarity to certain forms belonging to the family Cawthocamptidce.

Occurrence. I have met with this form not unfrequently in several places
both on the south and west coasts of Norway, as also in the Trondhjem Fjord,
in the littoral region among algae. On account of its small si/e and inconspicuous
colour, it is, however, easily overlooked.

Disti-Hi/itiun. Mediterranean (Glaus), British Isles (Scott), ? Gulf of Guinea
(same author), coast of Bohusliln (coll. Gleve), Spitsbergen (Scott), Franz Josef
Land (do.). Polar Islands north of Giinnell Land (2nd Fram Kxped.).

125
Gen. 33. DaCtylOpUSla, Norman, 1903.

Syn : Nauplius, Philippi (not Miillev).
Dactylopus, Claus (not Gill).

Generic Characters. Body, as a rule, rather stout, tapering behind, with the
anterior division more or less depressed and generally not sharply marked off from
the posterior. Cephalic segment large, but not very deep, rostrum well defined at
the base. Urosome with none of the segments expanded laterally; caudal rami
short. Anterior antenna) comparatively short, with a somewhat varying number
of joints. Posterior antennae with the proximal joint not divided in the middle,
outer ramus composed of 3 well-defined joints. Oral parts normal. 1st pair of
legs with the outer ramus generally much shorter and stouter than the inner,
terminal joint lamellar and armed with 4 strong outward-curving claws and a
slender seta inside the latter; inner ramus distinctly 3-articulate, with the outer
2 joints quite short, the last carrying 2 strong claws. Natatory legs well deve-
loped, with the rami rather broad, the inner one somewhat shorter than the outer
and having 2 setffi inside the middle joint; inner ramus of 2nd pair of legs in
male conspicuously transformed, biarticulate, with a strong spine outside the distal
joint. Last pair of legs in female with both joints generally broad and lamellar ;
those of male, as usual, much smaller.

Remarks. This genus was established as early as the year 1840 by
Philippi ; but the name he applied to the genus, Nauplius, cannot properly be
accepted, since it was used by 0. Fr. Midler in a very different sense, and at
present is in general use to distinguish the well-known earliest larval stage of lower
Crustacea. Nor can the generic name proposed by Claus, Dactylopus, be employed,
as it was appropriated some years previously by Gill for a genus of fishes. For
this reason, the Rev. A. M. Norman has recently proposed the change of the Clausian
name to Dactylopusia. 1 ) The genus was taken by Claus in a much wider sense
than here adopted, and Boeck had already called attention to the fact that some of
the Clausian species of Dactylopus ought to be separated generically. Still, how-
ever, recent British authors refer to this genus forms, which, by the presence of
2 ovisacs, clearly show themselves to belong to quite a different family, viz., the
Diosacehlir, to be treated of farther on. Even in the restriction here adopted,
this genus seems to comprise a great number of species from different parts of
the oceans. To the Norwegian fauna belong at least 5 well-defined species, to
be described below.

') Should perhaps more properly have been Dacti/lopodia.
17 Crustacea.

126

79. Daetylopusia thisboides (Glaus).

(PI. LXXVII & LXXVIII, %. 1).

Da<-t[/]aj>iiN thisboides, Glaus, Die freilebcndi-n Copcpoden, \>. 127, PI. XVI, figs. 24 28.

Specific ClinriK-tcr*. Fcinuli-. Body moderately slender, conspicuously
dilated in front and gradually tapered behind. Cephalic segment rather broad,
depressed, evenly arcuate in front, and scarcely longer than the 3 succeeding
segments combined; rostrum of moderate size, obtuse at the tip. Epimeral plates
of the 3 succeeding segments comparatively small and rounded at the posterior
corners. Urosome exceeding half the length of the anterior division, genital seg-
ment of moderate size and considerably broader in front than behind. Caudal rami
short and broad, apical seta?, however, rather elongated, the innermost but one
almost twice as long as the urosome. Anterior antenna? rather short and densely
setiferous, composed of 8 joints, 4 of which belong to the distal part, the latter
about as long as the 3 preceding joints combined. Posterior antenna? with the
outer ramus well developed, terminal joint about the length of the other 2 com-
bined. 1st pair of legs moderately strong, outer ramus scarcely more than half
as long as the inner, apical claws only slightly curved and finely spinulose on
the concave edge; inner ramus scarcely narrower than the outer, with the apical
claws strong and distinctly spinulose, the outer one exceeding half the length of
the inner. Last pair of legs with the distal joint not very large, rounded oval in
form and more or less exstant, so as to be generally wholly visible in the dorsal
view of the animal, marginal seta? 6 in number, some of them very slender and
elongated; inner expansion of proximal joint very large and broad, foliaceous,
extending beyond the tip of the distal joint, and provided inside the inner edge
with a regular row of short transverse chitinous stripes. Ovisac large, pyriform.

Mai/ much smaller than female, and exhibiting the usual sexual differences.
Inner ramus of 2nd pair of legs with the distal joint somewhat curved at the tip,
which carrier -2 rather unequal spines, spine of outer edge very strong and con-
spicuously expanded at the base. Last pair of legs much smaller than in female,
distal joint short, cordate in form, with only 5 marginal seta 1 . 2 of them spini-
toini; inner expansion of proximal joint very slight, with :j subequal marginal
spines.

I'xidy of a golden yellow hue, with a chestnut-coloured transverse band
the .-interior part of the genital segment.

Li'ii.nlh of adult female about 1 nun.

lt< ///"//>. This form I regard as the type of the present genus. It is the
and finest of the Norwegian species, and is moreover easily recognizable

127

by the general form of the body and more particularly by the structure of the
last pair of legs in the female.

Occurrence. Off the west coast of Norway this form is by no means of
rare occurrence in the littoral region. I have taken it rather plentifully at
Aalesund and Christiansund, as also in the outer part of the Trondhjem Fjord,
and it is also recorded by Th. Scott from the Finmark coast.

Distribution British Isles (Brady), coast of France (Canu), Mediterranean
(Glaus), the Red Sea (A. Scott), Bear Island (T. Scott), Franz Josef Land (same
author).

80. Daetylopusia negleeta, G. 0. Sars, n. sp.

(PI. LXXVIII. fig. 2).

Dactylopm thisboides (brackish water variety), Brady, Monograph of British Copepoda, Vol. 11,

p. 108, PI. LIV, figs. 1416.

Specific Characters. Female. Body somewhat more slender than in D.
thisboides, and less regularly tapered behind. Cephalic segment less broad, with
the rostrum more prominent. Urosome with the segments more sharply marked
off from each other, each with a very conspicuous transverse row of spinules near
the hind edge ventrally and laterally. Anterior antennse comparatively more
slender and distinctly 9-articulate, distal part exceeding the length of the 3 pre-
ceding joints combined. Posterior antenna? with the outer ramus comparatively
smaller. 1st pair of legs with the outer ramus considerably exceeding half the
length of the inner, apical claws of moderate length and scarcely spinulose, apical
claws of inner ramus very unequal, the inner one more than twice as long as the
outer. Last pair of legs rather different in shape from those in D. tliisboides,
distal joint comparatively larger, oval cordate in form and edged with 7 not much
elongated setffi, 2 of which issue from the inner edge; inner expansion of proximal
joint much smaller than in D. thishoides, extending only slightly beyond the middle
of the distal joint; none of the marginal setse remarkably elongated.

Male having the distal joint of the inner ramus of 2nd pair of legs
scarcely curved at the tip, apical spines subequal in length, spine of outer edge
more slender than in D. thisboides and attached rather in front of the middle.
Last pair of legs resembling in shape those of female, but of smaller size and
with only 3 marginal spines on the proximal joint.

Colour pale yellow.

Length of adult female 0.85 mm.

12s

/' marks. This form was considered by Prof. Brady as only a variety
of J>. ////>//-/'/'-. It is. however, certainly specifically distinct, as is clearly
proved, both by tbe distinctly 9-articulate anterior antenna. 1 and by the rather
different structure of tbe last pair of legs. Moreover, tbe inner transformed
raiuus of tbe -Mid pair of legs in tbe male exhibits characteristic differences from
that in the male of 1). fltis/in'/ili-*.

( )rriii'i'i nc>'. I have hitherto only observed this form in a single locality,
viz. in the immediate vicinity of Trondhjem, where some few specimens were taken
from tidal pools.

ion. British Isles (Brady).

81. Dactylopusia vulgaris, G. 0. Sars (ne\\- name).

(PI. LXXIX, tig. 1).

Drtr////oy/).s >'//.'./;. Clans. Die freilebenden Copepoden, p. 12H, PI. XVI, figs. 1 6 (not = Can-

thocamptus Strihni, Bainl).

c Characters. Female. Body considerably shorter and stouter than
in the 2 preceding species, and conspicuously depressed throughout. Cephalic
segment fully as long as the 4 succeeding ones combined; rostrum well developed
and somewhat curved. Urosome scarcely exceeding half the length of tbe anterior
division, all the segments fringed at the hind edge ventrally with delicate spinules,
genital segment scarcely broader in front than behind. Caudal rami about as in
I), nri/ln-fit. Anterior antennae of moderate length and distinctly 9-articulate,
distal part about the length of the 3 preceding joints combined. 1st pair of legs
resembling in structure those in D. tuylrrtn. though having the apical claws of
both rami somewhat stronger and distinctly denticulated. Last pair of legs with
the distal joint broadly ovate or cordate in form, tip narrowly exserted and ear-
ning -1 unequal bristles, outer edge with 3 subeqiial seta 1 , inner one with a single
souie\\bat stronger seta; inner expansion of proximal joint rather large, though
!'-> broad than in It. llii*hi>i<lc*. and extending about as far as the distal joint,
both joinN exhibiting inside the inner edge a row of short transverse chitiiious
strip

Mnl<- with the inner raiuus of i_'nd pair of legs resembling in shape that
in />. a- i/li-rtii. apical spines, however, less strong, and spine of outer edge at-
tached to about the middle of the distal joint. Last pair of legs with the distal
joint much shorter than in female and provided with an additional seta inside.
inner expansion of proximal joint extending as far as the distal joint and car-
rying .'5 marginal seta 1 .

129

Colour dark yellow changing to olivaceous brown.

Length of adult female 0.70 mm.

Remarks. This form has been identified by Glaus with the Canthocamptus
Stromi of Baird, and all subsequent authors have followed Claus in this view.
In my opinion, however, such an identification cannot properly be maintained, as
the figures given by Baird clearly show his form to be not a Dactylopusia but
without doubt a Laophonte, and in all probability the species recorded by Boeck
as Laophonte curticauda. I have therefore found it necessary to give the present
form a new specific name, and to transfer that proposed by Baird to the above-
named species of Laophonte. The form here in question is nearly related to the
2 preceding species, though easily distinguishable by its much shorter and stouter
body, as also by the structure of the last pair of legs in the female.

Occurrence. This is by far the most common of our Dactylopusise and
perhaps one of the commonest Harpacticoicla, occurring along the whole Norwegian
coast, everywhere in the littoral region among algse, and often also found abun-
dantly in tidal pools.

Distribution. Heligoland (Glaus), coast of Bohuslan (coll. Cleve), British
Isles (Brady), coast of France (Ganu).

82. Dactylopusia mieronyx, G. 0. Sars, n. sp.

(PI. LXXIX. fig. 2).

Specific Characters. Female. Body resembling in its general form that
of D. vulgaris, though somewhat more slender and more tapered behind. Anterior
antennae very small, 9-articulate. penultimate and antepenultimate joints less di-
stinctly defined. 1st pair of legs with the outer ramus short and stout, scarcely
exceeding half the length of the inner, terminal joint lamellar, with the 2 outer-
most claws extremely small; apical claws of inner ramus very unequal, the inner
one much elongated, 3 times as long as the outer. Last pair of legs with the
distal joint comparatively smaller than in D. uulyaris and of a more regular oval
form, marginal setffi 7 in number, 2 of them issuing from the inner edge; inner
expansion of proximal joint large, triangular, extending as far as the distal joint,
none of the joints with chitinous stripes inside the edge.

Male with the inner ramus of 2nd pair of legs similar to that in D. rul-
garis, but having the apical spines more elongated and rather unequal, the outer
one slender, setiform, the inner very strong and somewhat lamellar at the tip.

130

Last pair of legs, as usual, smaller than in female, with the inner expansion of
the proximal joint shorter and provided with only 3 marginal setae.

Colour pale yellow, with dark red intestine.

Length of adult female 0.65 mm.

Remark*. This form may be easily distinguished from the preceding
species by the small size of the anterior antennae and by the structure of the 1st
and last pairs of legs. The small size of the 2 outermost apical claws on the
outer ramus of the 1st pair of legs is especially characteristic, and has given rise
to the specific name here proposed.

Occurrence. I have met with this form occasionally in the upper part of
the Christiania Fjord, as also in the neigbourhood of Trondhjem, in depths ranging
from 6 to 20 fathoms, muddy bottom.

83. Dactylopusia brevicornis (Glaus).

(PI. LXXX).
Dactijlopus brcrii'urniN. Clans, Die Gopepodenfauna von Nizza, p. 29, PI. Ill, figs. 20 2">.

Syn: Dadylopux latipcs, Boeck (not Scott).

Sjxri/ic Characters. Female. Body comparatively short and stout, with
the 2 divisions more sharply defined than in most other species. Cephalic seg-
ment rather large and broad, about the length of the 4 succeeding segments com-
bined; rostrum of moderate size, obtuse at the tip. Urosome considerably nar-
rower than the anterior division and only very slightly attenuated behind. Caudal
rami twice as broad as they are long, apical setce rather slender and divergent,
the innermost but one almost twice the length of the urosome. Anterior antenna)
remarkably short and robust, densely setifcrous, and consisting of only 5 distinctly
defined joints, 2 of which belong to the distal part, 3rd joint rather expanded
ami exhibiting a slight indication of a subdivision into 2 segments. Posterior
antennae with the terminal joint of the outer ramus very short. 1st pair of legs
rather strongly built, with both rami comparatively short and broad, the inner
one being only slightly longer than the outer, apical claws of both rami remarkably
strong and curved, minutely denticulated on the concave edge. Last pair of legs
with the distal joint oblong oval, somewhat tapering distally, and more or less
extant, being visible in the dorsal view of the animal, marginal seta) 6 in number
and rather slender; inner expansion of proximal joint of moderate size, scarcely
however extending as far as the distal joint, marginal setae rather unequal, the
middle one much longer than the others. Ovisac narrow oblong in form.

Male with the inner ramus of 2nd pair of legs rather unlike that in the
other species, the distal joint being considerably shortened, and having the outer
edge fringed with long delicate cilia, tip armed with a remarkably strong angu-
larly bent spine. Last pair of legs with the distal joint of about same shape as
in the female, but of smaller size and only provided with 5 marginal setae; inner
expansion of proximal joint, as usual, far less prominent and carrying 3 spini-
form setse.

Colour pale yellow, urosome and part of metasome tinged with orange.

Length of adult female 0.63 mm.

BemarJcs.This is a very distinct and easily recognizable form, differing
in some points rather markedly from the other species. The Dactylopus latipes
of Boeck is unquestionably identical with Claus's species. This is however not
the case with the form described by Scott under the same name from the Gulf
of Guinea.

Occurrence. I have only met with this form quite occasionally in the
upper part of the Christiania Fjord, as also in some places on the west coast of
Norway. The specimens were found among algae in the littoral region. Th. Scott
also records this form from the Finmark coast.

Distribution. Mediterranean (Glaus), British Isles (Brady).

Gen. 34. DaCtylOpOdella, G. 0. Sars, n.

Generic Characters. Body much dilated and slightly depressed in front,
attenuated behind. Cephalic segment large and expanded, with the rostrum well
developed and deflexed. Urosome much narrower than the anterior division;
caudal rami short, apical sette normal. Anterior antennae comparatively small,
with the number of articulations reduced. Posterior antennae with the outer ramus
of moderate size, Inarticulate. Oral parts normally developed. 1st pair of legs
with the outer ramus shorter than the inner and somewhat resembling that in the
genus Dactylopusia, though having the apical claws much more slender and geni-
culate; inner ramus only composed of 2 joints, the proximal one only slightly
dilated, distal joint armed with 2 very strong subequal claws. Natatory legs with
the outer ramus much longer than the inner and densely spinulose outside; inner
ramus of 2nd pair of legs with the 2 outer joints in both sexes confluent, in
male tipped with a strong spine, outer edge unarmed. Middle joint of same ramus

132

in 3rd and 4th pairs with only a single natatory seta inside. Last pair of legs
poorly developed, distal joint very small, with some of the marginal setae spiniform.
Reiwtrk*. This new genus is founded upon the form recorded by Glaus
as Dactt/ltijiii* (htrttx, which on a closer examination has proved to differ in some
of the anatomical details rather conspicuously from the other species of the old
genus 'Dactt/li>i>/ix, so that it more properly ought to be generically separated.

84. Daetylopodella flava (Glaus).

(PI. LXXXI).
/lams, Clans, Die Copepoden-Fanna von Nizza, p. 28, PI. Ill, figs. 13 16.

Specific Characters. Fcmnle. Body short, pyriform in outline, with rather
strongly chitinized integuments. Cephalic segment very large and broad, fully
twice as long as the 3 succeeding segment combined, dorsal face evenly vaulted;
rostrum rather strong, pointing straight below, tip blunted. Epimeral plates of
the 3 succeeding segments small, rounded behind. Last segment of metasomc
considerably narrower than the preceding ones. Urosome scarcely attaining half
the length of the anterior division and slightly tapered behind; posterior edge of
the segments finely spinulose ventrally. Caudal rami broader than they are long,
middle apical setae rather elongated, innermost seta small and simple. Anterior
antennae composed of 6 joints only, 2 of which belong to the distal part. 1st
pair of legs with the outer ramus shorter than the proximal joint of the inner,
terminal joint lamellar, with the apical claws very slender and gradually increas-
ing in length inwards, seta attached inside the claws much elongated; inner ramus
with the seta of the proximal joint attached beyond the middle, distal joint short,
slightly widening towards the tip, apical claws very strong, falciform, and distinctly
denticulated on the concave edge. Spines of the outer ramus in all the legs densely
pectinate outside. Last pair of legs with the distal joint very small, subcordate,
with 5 very unequal and partly spiniform marginal setae; inner expansion of
proximal joint rather broad and likewise provided with 5 marginal setce, the outer-
ni"-t but one much longer than the others. Ovisac comparatively small.

Mule agreeing with the female both in general form and structure, though
exhibiting the usual sexual differences. Anterior antennae very stout and appa-
rently only composed of 4 joints, the penultimate much dilated, vesicular, the last
hamiform and very mobile. Inner ramus of 2nd pair of legs tipped with a strong
spine. Last pair of legs resembling those in female, but having the inner expansion
of the proximal joint much less prominent and only provided with 2 marginal setae.

Thalestridae

Copepoda

'Harpacticoida

n. LXV.

G .0. Sars, a utogr.

Parathalestns Clauei, (Norman.)

Norsk Lithgr. Officin.

Thalestridae

Copepoda

Harpacttcoida

PL LXVL

6.0. Sars, autogr. Norsk Lithgr. Officin.

Parathalestris Glaus i, (Norman.)
(continued)

Thalestridae

Copepoda

Harpacticoida

PL LXMI

G.O. Sars. autogr. Norsk LJthgr. Officm.

Rarathalestns harpacticoides, (Claus.J.

Thalestrid

Copepoda

Harpacticoida

FLDOffll.

G.O. Sars, autoar

Iparathalestris hibernica, (Brady s Rob.)

Norsk Lithgr. Officin.

ThalestridaB

Copepoda

Harpacticoida

Fl. LXK.

G .0. Sars. autogr.

F^rathalestris Jacksoni, (Scott.)

Norsk Lithgp. Officin.

Thalestridae

Copepoda

Harpacticoida

PL LXX.

G.O. Sars, autogr.

PhyUothalestn's mysia, (Glaus)

Norsk Lithgr. Officin.

Thalestridae

^^^^^^H^^^^H

Copepoda

Harpacticoida

PI. LXXL

G .0. Sars, autogr.

Phyllothalestris mysis,(Clau8J
(continued)

Norsk Lithgr. Officin.

Thalestridas

Copepoda

Harpacticoida

Fl. LXXII.

9

G.O. Sars, autogr.

Hatithalestris Croni ; (Kroyer.)

Norsk Lithgr. OfPicin.

Thalestridae

Copepoda

Harpacticoida

PL Lxxiir.

, ' >

v S>

G. 0. Sars. autogr. Norsk Lithgr. Officin.

Rhynchothalestris rufocincta, (Norm.)

Thalestridae

Copepoda

Harpacticoida

PI LXXIV.

' ^al : . '

m
*J%/P

6.0. Sars, autogr. Norsk Lithgr Officin.

Rhynchothalestn's rufocincta, (Norm.)

(continued)

Thalestridae

Copepoda

Harpacticoida

L. EXXY.

-

i ! r

?

.

13.0. Sars autogr.

Rhynchothalestris helgolandica , (Clausj

Norsk Lithgr. OfTicin.

Thalestridas

Copepoda

Harpacticoida

'

-

G.6. Sars, autogr.

Nccsk Litngr. Offioin.

Microfhalestris forflcula, (Ciaus.)

Thalestridas

Copepoda

HcLrpacticoida

PL LXXII

.'

/>

f

G.O. Sars. autogr. Norsk Lithgr. OfPicin.

Dactylopusia thisboides (ClausJ

Thalestridae

Copepoda

Harpacticoida

Pl.LXM.

6.0. Sars, autogr.

Dactylopusia thisboidea (CiausJ

(continued)
Dactylopusia neglecta , G.O.Sars

Norsk Litngr. Officin.

AN ACCOUNT

OF TIIK

CRUSTACEA

OF

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS XI & XII

THALESTRIDJE (concluded), DIOSACCID^] (part)

WITH 16 AUTOGRAPHIC PLATKS

BERGEN

PUBLISHED BY THE BERGEN MUSEUM

sui.r> cv

ALB. OAMMEBMEYER'S FOKLAC. CHUISTIAXIA

1906

l:;:;

Colour yellowish.

Length of adult female 0.50 mm.

Remarks. The above-described form is unquestionably that originally
recorded by Glaus as Dactylojms flams. Prof. Brady has confounded this species
with another very different form, to be described below as Idomctic for/in, ///
Philippi, only the female being referable to the present species, whereas the mah-
belongs to the Philippian species.

Occurrence. I have only met with this form very occasionally, though
in several localities off both the south and west coasts of Norway. It occurs in
moderate depths, ranging from 6 to 20 fathoms, among algse and Hydroida.

Distribution. British Isles (Brady), Mediterranean off Nice (Glaus).

Gen. 35. IdOmene, Philippi, 1843.

Generic Characters. Body pronouncedly depressed throughout, with the
anterior division broad and flattened. Cephalic segment rounded in front, without
any true rostrum. Urosome much narrower than the anterior division, though
distinctly depressed, last segment deeply cleft behind. Caudal rami produced,
divergent, inner apical seta spiniform. Eye absent. Anterior antenna? in female
comparatively small, 6- or 7-articulate, in male much larger and very subchelate.
Posterior antenna with the outer ramus well developed, biarticulate. Mandibular
palp largely developed, with the basal part very broad, and both rami of unusual
si/.e, the outer one armed outside with a number of strong falciform spines.
Maxillae and maxillipeds normal. 1st pair of legs with the basal part very broad
and flattened, both rami 3-articulate, the outer one shorter than the inner, and
armed outside with strong denticulated spines, inner ramus with the 1st joint
large and dilated, carrying inside a strong plumose setse, last joint armed at the
tip with 2 slender claws and a ciliated seta inside them. Natatory legs with the
rami nearly equal-sized ; inner ramus of 2nd pair of legs in male only slightly
transformed. Last pair of legs not very large, distal joint armed outside with
strong spines.

EemarJcs.This genus was established in the year 1843 by Philippi, to
include a small Copepod found by him in the Mediterranean at Naples. As only
a solitary specimen was observed, the exact structure of the appendages could of
course not be made out, and the detail-figures given merely represent some parts

18 Crustacea.

134

of the limbs as occasionally seen extended beyond the edges of the body. The
genus is chiefly characterised by the Hat clypeiform body, the absence of an eye
and of a true rostrum, the great development of the mandibular palps, and the
structure of the 1st pair of legs. In addition to the typical species described
below, the 2 forms recorded by A. Scott from Ceylon as Dri//li>tt*itt
and />. ''mala, seem to be referable to the present genus.

85. Idomene forfieata, Philippi.

(I'l. 1. XXXII).

. I'hilippi. 1-Vrnore TVolinrlitungen fiber die Copepoden des Mittelmeeres. Ardiiv
1. Xatnrgescliiclite 1843, p. 65, PI. Ill, fig. 4.

Syn: Dactylopus flfims Brady, male (not Clan- 1.

>. Body comparatively short, clypeiform. attenu-
ated behind. Cephalic segment large and expanded, evenly rounded in front.
lateral corners acutely produced. Epimeral plates of the 3 succeeding segments
laterally extended and terminating behind in an acute point. Last segment of
metasome much narrower than the preceding ones, and without distinct epimeral
plates. Urosome scarcely more than half the length of the anterior division,
genital segment nearly twice as broad as it is long, and imperfectly divided in
the middle, last segment cleft almost to the base. Caudal rami considerably
longer than they are broad, and slightly tapering distally. apical setc comparatively
short, the innermost one transformed to a strong mucroniform spine. Anterior
antennae narrow and gradually tapering distally. 7-articulate, terminal part about
half the length of the proximal one. Posterior antennae with the outer ramus about
the length of the terminal joint of the inner, and provided with 6 sette, 4 lateral
and 2 apical. Mandibular palp with the basal part very broad and expanded,
having a transverse row of delicate spinules across the middle, and 4 marginal
seta': rami of about equal si/.e, the outer one armed outside with 3 remarkably
strong spines, finely ciliated along one of the edges. 1st pair of legs with the
inner corner of the 2nd basal joint considerably projecting and armed with a
strong dcll.-xed spine: outer mums a little shorter than the 1 st joint of the inner.
exterior margin, as also the spun-. coarsely spinulose. last joint short and ob-
liquely truncated at the tip. carrying ;> spines and 2 geniculate setae: 1st joint of
inner raimis oblong trigonal in form, inner edp- angularly bent in the middle,
the outer -2 joints comparatively short, each with a ciliated seta inside, apical
claws strong ami sli^ht|\ unequal in length. Last pair of legs with the distal joint
comparatively small and armed with i> marginal spines, the 3 outer ones very

135

strong, inner expansion of proximal joint not very prominent, and broadly round. - ( 1
at the end, with 5 subequal setee, none of which are spinil'onu.

Male, as usual, somewhat smaller than female, and having tin- urosome
distinctly 5-articulate. Anterior antennae very strongly built, with the 4th joint
bulbously inflated, and the terminal part claw-like. First pair of legs of exactly
the same structure as in the female. Inner rainus of 2nd pair, as in the female,
distinctly 3-articulate, only differing in having the apical setae shortened and spi-
niform. Last pair of legs with the distal joint more oblong in form, and armed
outside with 4 very strong spines, inner expansion of proximal joint very slight,
and provided with only 2 marginal setae.

Colour yellowish, changing to a light chestnut-brown.

Length of adult female 0.54 mm.

Remarks. I think I am right in considering the present form to be
identical with that recorded by Philippi under the above name. The general form
of the body, at any rate, agrees fairly well with the rough figure, given by Phi-
lippi. As stated above, Prof. Brady has confounded this form with Diu-ti/liqn^
flavus of Glaus, only the female described being referable to Claus's species,
whereas the male unquestionably belongs to the form here treated of.

Occurrence, I have found this form occasionally in several localities off
both the south and west coasts of Norway, from the Christiania Fjord at least to
the Trondhjem Fjord. It occurs in moderate depths, ranging from 6 to 20 fa-
thoms, among algae and Hydroida. As is the case with the species of the genera
AspnViscns and Porcell'l'ii., the animal has the power of applying its flat body
so firmly to any object that it can only with considerable difficulty be detached
when alive. On coming in contact with the surface of the water, it remains
floating upon it, like some other Copepoda, and may thus easily be picked up
from any freshly taken sample.

Distribution. British Isles (Brady), Mediterranean at Naples (Philippi).

Gen. 36. AmenOpMa, Boeck. ISO.").

Generic C Vrm-/r,x Body flat, shield-like, recalling in general appearance
that found in the species of the genus Zaus: rostrum, however, ohsolrtr.
quite normal. Anterior antenna; of the usual structure. 9-articulate, in male only
slightly dilated, though distinctly prehensile. Posterior antenme with the outer

136

ramus rather small. Itiarticulate. Oral parts on the whole normal. 1st pair of
legs somewhat resembling in structure those in '/'/;'//< >///>. both rami being dis-
tinctly prehensile and subequal in length, armed at the tips with strong claw-
like spines. Natatory legs comparatively slender, with both rami 3-articulate,
the outer one being the longer: inner ramus of 2nd pair of legs in male trans-
formed in a similar manner to that in Thuli'stri*. Last pair of legs with the
inner expansion of the proximal joint very broad but only slightly projecting,
distal joint narrow, sub-falciform in shape, and extended laterally.

l\t'>mn'k*. This genus was established in the year 1865 by Boeck, to
include a species found by him off the west coast of Norway. It was however
not accepted by Prof. Brady, who in his Monograph referred the species described
by Boeck to the genus Thtilrttrix : and all subsequent British authors have fol-
lowed him in this view. True, one of the characters on which Boeck based his
genus, viz . the supposed duplicity of the eye, must be wholly cancelled, being
due to a miscomprehension; but there still remain several peculiarities which
seem to warrant the maintenance of this genus. In no other Thalestridse does
the body exhibit such a pronounced shield-like form, and indeed, for this reason,
Glaus would certainly have referred the genus to his family I'rltitliidti'. Moreover
the structure of the 1st and last pair of legs is somewhat different from that in
other ThalestridaB. Two closely-related species of this genus occur off the Nor-

wegian coast.

86. Amenophia peltata, Boeck.

(PL IAXXIII. I'l. I, \\XIV. fig. 1).

ia /"//,, In. I; ..... -k. Ovi-r^t over <] \-<-<\ Norm's Kvster i;n;-tt;i^iif Cn|n'|nM|rr, Clir. Yi'l.

Selsk. l-'m-li:ii).ll.

S\ n : Tlitili-nfris /iflfd/ti. Hr:nly.

Specific Characters. Female. l>ody oblong oval in outline, about twice
as Ion- as it is broad, the greatest width occurring somewhat in front of the
middle. Cephalic segment very large and expanded, slightly contracted, anteriorly,
front obtusely produced, lateral cornel's acuminate. Kpimeral plates of the .'>
succeeding segments extended laterally, and terminating behind in an acute point.
Last segment of metasome much narrower than the preceding ones. Crosome
about half the length of the anterior division, and. like the latter, distinctly de-
pressed, genital segment twice as broad as it is long, and imperfectly divided in
the middle, lateral ed^es of this and the 2 succeeding segments densely ciliated.

137

Caudal rami short, quadrangular, apical setae of moderate length. Anterior ;m-
tennse scarcely more than half the length of the cephalic segment, and only slighth
attenuated, distal part about half as long as the proximal one. Posterior an-
tennae with the outer ramus considerably shorter than the terminal joint of tin-
inner, and provided with 5 setae, 3 lateral and 2 apical. 1st pair of legs com-
paratively strongly built, outer ramus fully as long as the inner, and having the
middle joint rather elongated, spine of this and the preceding joint coarsely pec-
tinate on the one edge, last joint short, lamelliform, and armed with 2 small, and
2 very strong claws, inside which a slender ciliated seta is attached ; inner ramus
with the seta of the 1st joint attached about in the middle, the 2 outer joints
short and thick, apical claws rather unequal, the inner one very strong, the outer
shorter and much narrower. Last pair of legs with the distal joint rather nar-
row and densely hairy outside, inner edge straight, outer convex and carrying in
its distal part one large, and 2 very short setae, tip provided with 3 seta 1 , the 2
outer of which are very thin and unciliated; inner expansion of proximal joint
broadly rounded at the end, and carrying 5 unequal setae. Ovisac large, rounded
and distinctly applanated.

Male somewhat smaller than female, and having the urosome compara-
tively less broad and distinctly 5-articulate. Anterior antennae more strongly
built and distinctly prehensile, the hinge occurring between the first 2 joints of
the terminal part. Spine inside the 2nd basal joint of the 1st pair of legs trans-
formed into a strong hook. Inner ramus of 2nd pair of legs with the 2 outer
joints confluent, and at their junction, outside, provided with 2 closely juxtaposed
slender spiniform appendages, tip produced in 2 short and somewhat unequal
spines. Last pair of legs with the distal joint comparatively shorter than in female,
and having the 3 sette of the outer edge of equal si/e ; inner expansion of
proximal joints very slight, with only 3 marginal setae.

Body in both sexes of a light yellowish colour, with 2 or 3 dark viola-
ceous transverse bands across the anterior division, and several less distinctly
defined bands of a similar hue across the urosome.

Length of adult female 0.74 mm.

Remark*. This form was recorded by Boeck as parly as in the year
18H5, and was subsequently also found off the British Isles by Prof. Brady, who.
as stated above, referred it to the genus Tlittlrxtrix. In its external appearance
it somewhat resembles Zaus .^uuitiix, though, on a closer inspection, easily dis-
tinguished by the want of a true rostrum and by the peculiar colour of the body
when alive.

138

On-i i ,', <')!<<'. I have met with this i'onn occasionally in several localities
both on tin- -outh and west coa-t- f Norway, from the < 'hristiania Fjord up to
the Triuidhjeii) Fjord. It is not, like /mis +/HI/II/H*. a strictly littoral species, but
only occurs in moderate depths ranging from (> to 20 fathoms.

/)i*frt/nifiii)i. British Isles (Brady), coast of Bohuslan (coll. Cleve).

-s. Amenophia pulchella, G. 0. Sars. n. sp.

(PI. LXXXIV. fig. 2).

>// .ri/ir ('li<ir<t<-h'r*. F> nn/!/ . Body comparatively shorter and stouter
than in the preceding species, rounded oval in outline, with the greatest width
considerably exceeding balf the length, and occurring about in the middle. Ce-
phalic -eminent very large and only slightly constricted in front. Epimeral plates
of the ,'j succeeding segments closely imbricate and greatly exstant laterally.
Urosome comparatively short and broad, scarcely half as long as the anterior
division, the first .'! segments considerably produced at the lateral corners, and
densely fimbriate at the edges. Caudal rami about as in .-1. jirlfutit. Anterior
antenna' somewhat more attenuated distally. terminal part very slender. Posterior
antenna 1 and oral parts scarcely different from those in .1. fu'llnfu. 1st pair of
legs likewise of a very similar structure, differing, however, in the somewhat
greater length of the inner ramiis as compared with the outer, and having the
seta of the 1st joint attached beyond the middle. Last pair of legs with t'.ie
terminal joint of tin- same structure as in J. jirltntn : inner expansion of proximal
joint however slightly different, being narrowly produced in the middle.

Body of a clear yellowish colour, with a bright pink band across the
middle, occupying the whole of the first .'5 free segments of meta-oine. and bor-
dered in front by a light orange shade.

Length ol adult female o 5o mm.

/,' >n<trk*. This new species is closely allied to .1. iii'lhthi, but is of smaller
size and considerably more robust form of body, differing also slightly in the
structure of the 1st and last pairs of legs. In the lixini; state, it is moreover
at once distinguished by its peculiar and beautiful colour.

Occurrence. Some few specimens of this form, all of the female SCX,
\\ere taken main years aiM> at < 'hrisl ian-iind. on the we-l coast of Nor\\a\.

139

Gen. 37. WeStWOOdia, Dan;). L855.

Syn: Pseudothalestris, \\r-.x\\.
Pseudowestwoodia. Scott.

Generic Characters. Body short and stout, sub-pyriform in shape, with
the anterior segments more or less imbricate dorsally. Cephalic segment very
large and boldly vaulted above, rostral projection deflexed, not defined at the
base. Urosome comparatively small, attenuated. Caudal rami short and broad.
Eye well developed. Anterior antennae with the articulations more or less reduced
in number. Posterior antennae with the outer ramus of moderate size, 3-articu-
late. Oral parts differing somewhat in structure from those in the other Thale-
stridas. Anterior lip very prominent. Mandibles with the masticatory part nar-
rowly produced, palp well developed, with the basal part oblong in form, and
both rami short, the outer one abruptly reflexed and carrying long plumose setse.
Maxilla? with the masticatory lobe likewise considerably produced, and terminating
in a claw-like projection. Anterior maxillipeds short and stout, with a strong
incurved claw at the end, lateral lobes comparatively simple. Posterior maxil-
lipeds powerfully developed and of normal structure. 1st pair of legs with the
rami very unequal, the outer one being quite short and composed of only 2 joints,
which in some cases are confluent in one, inner ramus elongated, 3-articulate.
resembling in structure that in the genus T/m/rx/nx. Natatory legs normally
developed, having the proximal joints of the rami rather broad; inner ramus of
2nd pair of legs in male transformed, being only composed of 2 joints, the last
one more or less lamellar, with 2 unequal spines at the tip, and another issuing
near the base outside. Last pair of legs with the distal joint comparatively small,
proximal joint more or less lamellarly expanded inside; marginal setaa generally
much elongated.

Remarks. This genus was established by Dana as early as the year 1855.
to include the form described by Baird as Ari.xn-tlrttx iioli'il'i*. The genus Pxctnlii-
ihalestris of Brady cannot in my opinion be supported, as the only distinguishing
character, the biarliculated structure of the outer ramus of the 1st pair of legs,
is also found in a species - - to be described below - - which so closely resembles
the type of the genus Westiwodia. that it may easily be confounded with it. As
to the systematic position of the present genus, the opinions of carcinologists have
been somewhat at variance. Boeck associated this genus with Jrfj/a in his sub-
family Idy'ma', on account of the narrowly-produced mandibles, whereas Prof.
Brady rightly removed it from that place, and included it in his subfamily I/nr-
which, however, contains forms referred in the present account to 4

140

different families. I think the genus ought more properly to be placed within

the family Tlntlr*tri<hv as here defined, though in some respects it certainly differs

conspicuously from the other genera. (Ml the Norwegian coast occur 4 species
referable to this genus.

88. Westwoodia nobilis (Baml).

(PI. LXXXV & LXXXVh.
s iii>l>Uis. Hninl. Kritish Kntniuostnica. |>. 1^14, I'l. j>N, ti^s. '1, "2 a e.

Specific Character*. I-\iii<ilc. Body very robust, somewhat compressed
in front, attenuated behind. Cephalic segment occupying almost half the length
of the entire body, and rather deep; dorsal face strongly vaulted, rostral projec-
tion triangular, acute at the tip and pointing straight down. Epimeral plates of
the 3 succeeding segments of moderate size, deflexed and rounded behind. Last
segment of metasome much narrower than the preceding ones. Urosome scarcely
more than l / s as long as the anterior division, and gradually tapering behind.
genital segment about the length of the 2 succeeding ones combined, and imper-
fectly divided in the middle. Caudal rami broader than they are long, and trans-
versely truncated at the tip, apical seta? rather elongated and divergent. Anterior
antennae comparatively short and stout, composed of only 5 articulations, 2 of
which belong to the terminal part; middle joint much the largest and formed by
the fusion of 2 joints. Posterior antennae with the outer ram us shorter than the
terminal joint of the inner, 1st joint about the length of the other 2 combined.
1st pair of legs with the outer ramus scarcely V:: as long as the inner, and con-
sisting of only a single joint, no trace of any subdivision being visible; inner ramus
with the seta of 1st joint attached considerably in front of the middle, apical
claws finely pectinate on the one edge and rather unequal, the inner one being
more than twice as long as the outer. Last pair of legs with the distal joint
small and rounded in shape, carrying ."> slender seta-; inner expansion of proximal
joint extending as far as the distal joint, and edged with 5 very slender and
elongated set*. Ovisac large, pyriform, extending considerably beyond the end
of the urosome.

Mali differing only slightly, in its external appearance, from the female.
Anterior antenna- transformed in the usual manner, and consisting of 7 well-de-
fined joints, the 2 sensory appendages of moderate length. 1st pair of legs dif-
fering from those in female only as regards the spine attached to the inner corner
of the 2nd basal joint, which is quite short, tap-shap-.'d. and terminating in an

141

obtuse point. Inner ramus of 2nd pair of legs scarcely more than half as long
as the outer, distal joint obliquely oval in form, basal spine slender setiform,
inner apical spine much coarser than the outer, which terminates in a setiform
point. Last pair of legs considerably smaller than in female, inner expansion of
proximal joint less prominent and provided with only 3 setse.

Body variously ornamented with a more or less deep brownish red
pigment.

Length of adult female 0.87 mm.

Remarks. This form was recorded by Baird as early as the year 1845, *)
and was subsequently described and figured by the same author in his well-known
work on the British Entomostraca. Since that time it has been noted by several
authors, being an easily recognizable form, owing both to its unusually robust
body and to its gorgeous colour.

Occurrence. I have met with this form in several localities both on the
south and west coasts of Norway, but nowhere in any abundance. It occurs in
the littoral and sublittoral zones among algae, and is sometimes even left in tidal
pools. Th. Scott records this form also from Svolvser, in the Lofoten Islands.

Distribution. British Isles (Baird), Heligoland (Glaus), coast of France
(Canu), coast of Bohuslan (coll. Clove).

89. Westwoodia assimilis, G. 0. Sars, n. sp.

(PJ. LXXXVII).

Specific Characters. Female. Very like the preceding species both as to
size and general appearance. Rostrum, however, somewhat shorter and less acute
at the tip. Segments of anterior division distinctly imbricate dorsally, and more
evenly vaulted than in the type species. Anterior antennae still shorter and stouter
than in that species, but exhibiting the same number of articulations. Posterior
antennae and oral parts almost exactly as in W. nolili*. 1st pair of legs, how-
ever, differing conspicuously in the structure of the outer ramus, which is distinctly
biarticulate and about half as long as the 1st joint of the inner; seta of this
joint attached nearly in the middle. Last pair of legs likewise differing slightly
from those in the type species, the distal joint being comparatively larger and
more oval in form, with 6 marginal setse; inner expansion of proximal joint com-
paratively narrower, and not extendin, quite as far as the distal joint.

!) Transact. Berw. Nat. Club, Vol. II, p. 155.
19 Crustacea.

142

inhibiting tin- usual sexual differences from the female. Anterior
antenna' of a structure similar to that in the male of IT. )i!>//i*. being, however,
clearly distinguished by the enormous development of the 2 sensory filaments.
First pair of legs, as in the female, with the outer ramus distinctly biarticulate.
Inner ramus of ^nd pair of legs differing slightly from that in the male of IT.
nnlt'il'i* in the form and armature of the distal joint, the basal spine being quite
short, whereas the inner apical spine is rather strong and peculiarly transformed,
falciform and finely denticulated along the concave edge. Last pair of legs very
like those of the male of IF. noliili*. differing, however, in the comparatively larger
si/e of the distal joint, which is moreover provided with 6, instead of 5. seta'.

Colour not yet determined.

Length of adult female 0.82 mm.

Ill-murk*. According to the structure of the 1st pair of legs, this form
>hould really have been referred to the genus Pseudothalestris of Brady: but it
is evident that such an arrangement would be quite unreasonable, since in all other
respects the present species agrees so closely with the type of the genus UV>7-
icooilin, that a very close examination is needed in order to distinguish the two
species from one another. I think that the present species clearly shows that
the genus Pseudothalestris ought to be cancelled.

Occni'nin'e. I have hitherto only seen 2 females and one male specimen
of this form. They were recently found among a number of specimens of IF. 110-
Inli* collected at different times and from different places, and T am therefore at
present unable to state the locality in which the specimens occurred.

90. Westwoodia minuta, clans.

(I'l. 1A XX VIII. ti u . I).
tn niiiudd. I'laiiv. li,. rri-ilclit-ndi'ii < . i]i.'p. id. MI. \<. I 1 S. I'l. XXI, li^s. 10 14.

Syn: rxiH/lutJiiilrxfi-ix monenSlS, Brady.
major, Scott.

rr*.- l'"rmti!(\ Body very short and stout, pronouncedly
pyriform in shape, with the segments of the anterior division deeply imbricate
dorsally. Cephalic segment very large and deep, occupying rather more than
half the length of the entire body; rostral projection quite short, triangular. Kye
\ery conspicuous in the living animal. Anterior antenna; comparatively slender
and attenuated, composed of G well-defined articulations, 2 of which belong to the
terminal part, .'3rd and 4th joints the largeM and nearly equal in length. Posterior

J43_

antennae more slender than in the 2 preceding species, but otherwise of a
similar structure. Oral parts likewise constructed upon the vcrv same type. 1st
pair of legs with the outer ramus distinctly biarticulate and about hall the length
of the 1st joint of the inner ramus; seta of this joint attached considerably in
front of the middle, apical claws of the same ramus very slender. Last pair ..!'
legs with the distal joint very small, carrying 5 slender seta", inner expansion of
proximal joint considerably produced, extending far beyond the distal joint.

Male of about the same size as female, and not very different in external
appearance. Anterior antennae transformed in the usual manner. Inner ramus
of 2nd pair of legs with the distal joint oblong oval in form, apical spines about
as in IF. nobilis, basal spine, however, much stronger. Last pair of legs, as usual,
smaller than in female, with the inner expansion of the proximal joint less pro-
minent, and provided with only 3 setae.

Colour light chestnut-brown, with a very dark shade on each side of the
cephalic segment behind.

Length of adult female 0.50 mm.

Remarks. There cannot, in my opinion, be any doubt that the above-
described form is that originally recorded by Glaus as Westimodla /nun/ In, and
that both Pseudothalestris inonensis of Brady and P. -major of Scott belong to the
very same species. In its structural details it shows a near relationship to the
2 preceding species, and cannot by any means be generically separated from them.

Occurrence. I have found this form occasionally in several localities on
the south and west coasts of Norway, as also in the Trondhjem Fjord, in moderate
depths among algae; and Th. Scott also records it from the Finmark coast. A
peculiarity of this species is that in the living state, when disturbed, the animal
secretes a clear viscid fluid in considerable quantity. From which organ this
matter is derived, I have not yet been enabled to determine.

Dist filiation. British Isles (Brady, Scott), Heligoland (Glaus).

91. Westwoodia pygmaea (Scott).
(PI. LXXXVIII, fig. -2}.

Pscwlowestwoodia pijumd-a, Scott, Ann. & Mag. Nat. Hist. I'm- January, lM-\ [>. ">">. I'l. VI.

figs. 816.

Syn: Pseudothalestris )>i(ntini. Scott.

Sfurifjc Chantrti-rx.FenMk'. Body still shorter and stouter than in II.
minntd, with the segments of the anterior division very pronouncedly imbricate
dorsally. Gephalic segment of quite an extraordinary size, almost twice as long

144

as the remainder of the body, and dorsally mo-lapping the greater part of
the succeeding segment: rostral projection rather short. Anterior antenme com-
paratively shorter than in IT. iitiinitn. though composed of 7 well-detined arti-
culations, 3 of which belong to the terminal part. Posterior antenna? and oral
parts scarcely different from those in the said species. 1st pair of legs likewise
of a very similar structure, only differing in having the seta of the 1st joint of the
inner ramus attached about in the middle. Last pair of legs, on the other hand,
of a rather different appearance, the inner expansion of the proximal joint being
\ery slight, whereas the distal joint is considerably exserted at the tip.

Mull- differing from that of IT mhtufa chiefly in the structure of the
inner ramus of the 2nd pair of legs, the distal joint of which is rather broad
and angular in form, projecting both at the outer edge and at the tip in a denti-
form projection, inner apical spine very strong and curved, outer feeble. >etiform.

Colour yellowish with light brown shading.

Length of adult female 0.35 mm.

//(///////.-. This form bears a general resemblance to II'. inin/iln. but is
of much smaller size and shorter form of body. It also differs conspicuously in
the structure of the anterior antennae and the last pair of legs.

( )cni m')u-L'. I have met with this dwarf form not (infrequently in several
localities both on the south and west coasts of Norway, in moderate depths
among algre. It moves in a peculiar, tremulous manner, much as do the species
of the genus Tegnstf*.

. Scottish coast (Scott).

Fam. 11. Diosaccidse.

r*. Body of somewhat varying form in the different genera, but
never depn^ed as in some of the Thuh'slrnlii-: body-segments, as a mle. not very
sharply marked oil from each other. KoMrum well defined at the base, more
or les> mobile. Anterior antenna' short or of moderate length, generally s-articn-
late. in male distinctly prehensile. Posterior antenna 1 with the basal joint not
dhided, outer ramus comparath eh Miiall. Oral parts of someu hat different struc-
ture in the dilierent 'jenera. M pair of le.^s with the rami, as a rule, very un-
equal, the outer one bein.u geiieralh much shorter than the inner, and less di>-
tinctly prehensile than in the '/'//'//<.>// /,/// . Natatory hr- im.iv or less slender,

145

with both rami in female 3-articulate. Inner ramus of 2nd pair of legs in in.-il.-
transformed. Last pair of legs foliaceous, much larger in female than in male.
Ovisac double.

Remarks. The chief character distinguishing this family is the duality
of the ovisac, a feature otherwise very rarely met with in the Hai-j.acticoida. In
other respects this family exhibits a certain resemblance both to the Thuh'sh-rl,,-
and to the Canthocamptidce. To the Norwegian fauna belong 3 well dHin.-d
genera, to be treated of below.

Gen. 38. DiOSaCCUS, Boeck, 1H72.

Syn: Dactylopus, Claus (part).

Generic Characters. Body pronouncedly compressed in front, attenuated
hind, with the cephalic segment very large and deep, and the rostrum very
prominent. Anterior antennae comparatively slender, 8-articulate. Posterior an-
tennae with the outer ramus very small, uniarticulate. Mandibles with the masti-
catory part considerably dilated, cutting edge undivided, palp apparently simple,
with only a slight rudiment of an outer ramus. Maxillae distinguished by the
shortness of the masticatory lobe and the spines with which it is armed, palp
well developed. Anterior maxillipeds comparatively small, with only 3 lateral
lobes carrying short and thick digitiform spines. Posterior maxillipeds powerfully
developed, and of normal structure. 1st pair of legs with the outer ramus small,
not prehensile, inner much elongated and resembling in structure that in Tlt<i/r*tri*.
though having the seta of the 1st joint attached close to the end. 2nd pair of
legs with the terminal joint of the outer ramus comparatively smaller than in
the succeeding pairs, and provided with only 2 spines outside; inner ramus of
same pair in the male very short, biarticulate, terminating in a strong spine.
Last pair of legs not very large, with short, partly spinit'orm seta?; in male still
smaller, and having the 2 joints confluent.

Remarks. Tliis genus was established by Boeck in the year isTi'. to
include 2 of the species referred by Claus to his genii:, / >nr/?/lo/>ii*. \v/..
\cuniis and D. lonu'irostris. These 2 forms, though alike in having 2 ovisacs
are however e.idently generically different, and the Boeckian genus must of course
be confined to one of them. This has indeed been done by Prof. Brady,
describes the first-named species as the type of the genus Diosaccus

146

form, which was unknown to Prof. Brady, as also the form named by Boeck
I )i<^u,-i-iifi iilii/^i, belong- to the genus Aini>lii<t*cn*. recently established by the pre-
sent author. Tin- -THUS /)i<,sii<-r<is. in the restriction here adopted, differs con-
-piciumsly from the other '2 genera included in the present family, both in
external appearance and in several of the anatomical characters. In addition to
the typical form, another nearly-allied, though evidently distinct species has been
described by Th. Scott as Dt<>*n-n* i>r<>i>'tn<irns. Only tlie type species has as yet
been found off the Norwegian coast.

in.'. Diosaceus tenuieornis (Hans).

(I'l. LXXX1X i XC).

f ><i,'ti/li>j>iix tr)n<ii-tii-ni*. Clnus Die tVcili'liendrn ( 'Mpr|i<><lttii, p. 1^7, JM. XVI, !ii;s. 17 23.

N/yrr/'/'V ('hnr<i<-tfi-*. I'^'nnilc. Body moderately robust, with the anterior
division considerably broader than the posterior. Cephalic segment more than
twice as long as all the free segments of metasome combined, and evenly vaulted
above; epimeral parts very fully developed and much curved in the middle.
embracing between them the oral parts, only the posterior maxillipeds projecting
beyond their edge-. Rostrum somewhat lamellar and very prominent, being
slightly curved. Kpimeral plates of the ',} succeeding segments of moderate si/e,
delh-xed and angular behind. Last segment of metasome narrower than the pre-
ceding ones, and without distinct epimeral plates. Urosome scarcely more than
half the length of the anterior division, and rapidly tapering behind; genital seg-
ment considerably dilated in front, and divided in the middle by a somewhat
curved transverse line: last caudal segment longer than the preceding one. Caudal
rami closely juxtaposed and somewhat applanated. being slightly longer than they
are broad at the base, miter edge armed with a short spine beyond the middle.
apical M't;e -carcely diverging at all. the innermost but one much the longe-t.
Anterior antenna 1 unusually slender, with the joints of the proximal part nm-
-iderahly prolonged, the 2nd joint being the largest, terminal part not nearly
attaining half (lie length of the proximal part. 1'osterior antenna' likewise rather
Blender, witli the terminal joint long and narrow, outer ranius not nearly half as
hmg as tin- latter, and pro\ided with I seta 1 . 2 apical and 2 lateral. I 'ostcrior
maxillipeds \\ith the hand \cr\ large and deeply concaved inside, dactylus strong
and curved. 1st pair of legs rather slender, rami very unequal, the outer one
scarcely more than half as long as the inner, last joint somewhat shorter than
the other -2. and provided with :! spines successively increasing in length, and a

147

moderately long seta at the inner corner; inner ranms with the outer -2 joint-
short, apical claws slender and very unequal, the inner one i'ully twice as loni:
as the outer. Last pair of legs with the distal joint oblong in form and provided
in its outermost part with 6 rather unequal setae, inner expansion of proximal
joint considerably produced, narrow linguiform in shape, and extending beyond
the distal joint, marginal setfc 5 in number, the middle one very thin, the others
thick, spiniform and coarsely denticulated. Ovisacs large, pyriform, and some-
what divergent.

Male smaller than female, and exhibiting the usual sexual differences.
Anterior antennae transformed into strong prehensile organs composed of the same
number of joints as in the female. 1st pair of legs exhibiting inside the '2nd
basal joint a small linguiform lappet, not found in the female. Inner ramus of
2nd pair of legs scarcely as long as the 1st joint of the outer, distal joint rounded
and carrying a slender setiform spine outside, inside a long plumose seta, tip
produced to a strong, somewhat flexuous spiniform projection. Last pair of legs
rather unlike those in female, distal joint very short and imperfectly defined at
the base, carrying 3 denticulated spines and a small seta, inner expansion of
proximal joint almost obsolete, and only provided with 2 short setse. Genital
lobes each with a strong denticulated spine and 2 slender setse.

Colour generally a golden yellow, ventral face and bases of legs tinged
with dark indigo-blue.

Length of adult female 0.80 mm.

Remarks. This is an easily recognizable form, being especially distin-
guished by the large and deep cephalic segment, and the unusually slender anterior
antennae.

Occurrence. It is one of our commonest Harpacticoida, occurring ratlin
abundantly along the whole Norwegian coast in the littoral zone among alga-, and
not infrequently left in tidal pools together with other littoral forms.

Distribution. British Isles (Brady), coast of Bohuslan (coll. Cleve), Me-
diterranean (Glaus).

148

Gen. 39. AmphiasCUS, <:. (>. Sars, 1905.

s-\u: DactylopWl, Clans (|i;irt.
/>/.w/, ,/>. |',.,,.ck ( part).

Xt,-,tJ,,-lift. lii-aily. Src.tt (n<>t JJoeck).
ScJti :<>],". <i. <>. Sars.

Generic (Vm/w/r/x Body more or less slender, cylindrical in form, with
the anterior and posterior divisions not sharply marked off from each other.
Cephalic segment of moderate size and not very deep, rostrum well defined and
very mobile. Urosome with the genital segment in female imperfectly divided in
the middle, and scarcely dilated in front, posterior edge of all the caudal seg-
ments finely spinulose on the ventral and lateral faces. Caudal rami generally
short, apical setse slender. Anterior antennae of usual structure, and as a rule
uposed of 8 articulations, 4 of which belong to the terminal part. Posterior
antennae with the terminal joint more or less dilated distally, and armed outside
with strong spines, at the tip with slender gen'iculate setae; outer ramus very nar-
row, generally .'^-articulate, middle joint quite short and in some cases imperfectly
defined. Oral parts normal. 1st pair of legs with both rami triarticulate, the outer
one much shorter than the inner, and in some cases resembling in structure that
in the genus Dactylopusia, inner ramus with the 1st joint slender and elongated,
seta of inner edge attached close to the end. Inner ramus of 2nd pair of legs
in male more or less conspicuously transformed, outer 2 joints confluent. Last
pair of legs foliaceous, with the proximal joint more or less expanded inside;
those in male much smaller than in female.

/.'< tinii />. This genus was established by the present author in a recently
published paper on Pacific Crustacea 1 ), and on that occasion he called attention
to the fact that the genus Stcnliclin of British authors does not by any means
answer to that genus as defined by Boeck, the latter being in reality very clif-
1'i-n-nt. and closely related to, if not identical with, the genus /trlnniHn of Brady.
It therefore appeared necessary to substitute another yen ric name, to inclu '
the species erroneously referred to Boeck's genus. The genus Sclti:-,/'! ,'< estab-
lished by thf present author to include a Pacific species, 1 am now disposed to
withdraw, as some of the characters upon which this genus was founded have
proved to occur also in certain specie-, unquestionably belonging to the genus
.\,ni>lii'i*r/ts. It may here be noted that se\eral of the species referred by Claus,
and also by recent British authors, to the genus Zta^fa/fopwsia ought likewise to be
included in the present ".eniis. which seems to be very abundantly represented in

') "PacifiBChe HankUm l'i n" II. in /ool. Jalirlmrlirr 1905, p. iJ.SO.

149

different parts of the Oceans. I have been enabled to distinguish off the Nor-
wegian coast rather a large number of species, to be described in the following
pages. They all exhibit a very uniform external appearance, and of course are
not easy to distinguish when preserved, though in the living state they may in
most cases be at once recognized by differences in the colouring of the body.

93. Amphiascus cinctus (Clans).

(PI. XCI & XCII).
Dactylopus cinctus, Glaus, Die Copepodenfauna von Niz/a, p. 27, PI. Ill, figs. 8 IL J .

Specific Characters. Female. Body moderately slender, with the anterior
division but little broader than the posterior. Cephalic segment about the length
of the 4 succeeding segments combined, epimeral parts not very deep, and evenlv
rounded in front. Rostrum strongly prominent, lanceolate and slightly curved at
the tip. Epimeral plates of the 3 succeeding segments of moderate size and
slightly angular behind. Last segment of rnetasome scarcely narrower than the
preceding one. Urosome about 2 /a as long as the anterior division, and tapering
only very slightly behind, genital segment equalling in length the 2 succeeding
ones combined, anal segment somewhat shorter than the preceding one. Caudal
rami quadrangular in form, broader than they are long, the 2 middle apical setae
rather strong, spine of outer corner shorter than the corresponding ramus. An-
terior antennse moderately slender and densely setiferous, 8-articulate, the first
2 joints much larger than the others, 3rd and 4th of about equal size, terminal
part about, half the length of the proximal. Posterior antennse rather strongly built,
outer ramus with the middle joint well defined, setiferous. 1st pair of legs with
the outer ramus about half the length of the inner, middle joint much the largest,
terminal joint small, lamelliform and armed with 4 claw-like spines, inside which
a slender seta is attached; inner ramus with the 2 outer joints short, the laM
one armed on the tip with 2 very strong claws, the inner one the longer. Nata-
tory legs moderately slender and of normal structure. Last pair of legs very
large and foliaceous, distal joint of considerable size, rounded quadrangular in
form, and provided with 6 marginal seta3, the outermost one the shortest and
attached at rather a long distance from the base; inner expansion of proximal
joint triangular, scarcely extending ! ^voncl the middle of the distal joint, and
carrying 5 setse, the outermost one much the shortest. Ovisacs of moderate "size,
oblong pyriform in shape.

20 Crustacea .

150

Malt- somewhat smaller than female, and having the urosome distinctly
5-articulate. Anterior antenna.' more strongly built, and transformed in the usual
manner. Spine attached to the inner corner of the 2nd basal joint in the 1st
pair of legs of extraordinary si/e and somewhat sigmoid in form. Inner ramus
of "2nd pair of legs nearly as long as the outer, distal joint carrying 2 closely
juxtaposed spinif'orm appendages outside, of which the proximal is very strong, tip
armed with another somewhat more slender appendage curving outwards. Last
pair of legs much smaller than in female, distal joint oval in form, inner expansion
of proximal joint with only 2 marginal setae.

Bodv in both sexes of a whitish colour, with a broad transverse band of

ti

a deep pink hue across the middle, occupying the whole of the first 3 free seg-
ments of metasome; dorsal face moreover exhibiting along the middle a narrow
longitudinal band of a light orange colour.

Length of adult female 0.84 mm.

Remarks. This form was originally described by Glaus from the Mediter-
ranean as a species of his genus Dactylopus, the specific name apparently refer-
ring to the peculiar colouring of the animal. It does not seem to have been observed
by subsequent authors; for the suggestion put forward by Prof. Brady, that it
might only be a variety of Dti<-t///j>/ts Stromi Cls. (= D. nil (juris G. 0. Sars),
is so extremely unreasonable, that it is impossible to believe that the true Clausian
species has been observed by that author.

Occurrence. Some few specimens of this pretty form were found many
years ago oil the west coast of Norway. Last summer, I found it again not
(infrequently in 2 different localities on the south coast, viz., Risdr and Lillesand.
It occurs in moderate depths among algtc, and in the living state is at once
recognizable, even with the naked eye, from any other species of this genus, by
the peculiar and beautiful colour of the body, which seems to be perfectly constant
in all specimens, both male and female.

Distribution. Mediterranean off Nice (Clans).

94. Amphiaseus obscurus, G. 0. Sars, n. sp.

(PI. \cill).

N//rr/7/V ChnriK-ti i .-. I'":,,inlr. Body of comparatively more robust form
than in the preceding species, otherwise of a very similar appearance. Urosome
with the segments coarsely spinulose along the ventral and lateral edges. Caudal
rami comparatively more massive than in .1. <-inrt*. with the spine of the outer

151

corner more elongate, somewhat exceeding in length the corresponding ramus.
Anterior antennae comparatively shorter and stouter, H-articulate, distal p:irt ex-
ceeding half the length of the proximal one. Posterior antennae and oral pints
almost exactly as in the preceding species. 1st pair of legs likewise of a verv
similar structure, though having the outer ramus a little longer in proportion to
the inner. Last pair of legs with the distal joint very large and expanded, of a
broadly rounded form, and carrying 7 marginal setae, the outermost one some-
what longer than the next, and occurring not far from the base; inner expansion
of proximal joint extending somewhat beyond the middle of the distal joint, and
having the outermost seta longer than the 2 innermost ones. Ovisacs about as
in the preceding species.

Male resembling that of A. cinctus in its external appearance, as also in
the structure of the anterior antennae and the inner ramus of 2nd pair of legs.
Spine attached to the inner corner of the 2nd basal joint in the 1st pair of legs
comparatively smaller than in the male of A. riiict//*, and almost straight. Last
pair of legs with the distal joint comparatively shorter and broader, and the inner
expansion of proximal joint less prominent.

Body all over, except on the dorsal face of the cephalic segment, of
a very dark chocholate-brown colour, changing to a deep indigo-blue on the caudal
rami and ventral appendages.

Length of adult female about 1 mm.

Remarks. This new species is closely allied to A. cinctus, Claus, but is of
considerably larger size and more robust form of body, differing also slightly in
the structure of the anterior antennae and of the 1st and last pairs of legs. In
the living state it is moreover at once distinguished by the very different colour

of the body.

Occurrence. I found this form last summer at Risor and Lillesand, on the
south coast of Norway, in moderate depths among algae. On account of the rela-
tively large size of the specimens and their very dark colour, it was a compara-
tively easy task to select them from the freshly-taken bottom-samples, even
without the aid of a magnifying lens.

95. Amphiaseus similis (Clans).

(PL XCIV).
Daclylopus similis, Clans. Die Copepoden-Faima von Ni/x.a, p. -!.'>. I'l. II, figs.

Specific Characters. Female. Body very slender and pronouncedly cylin-
dric in form, the anterior and posterior divisions being of almost uniform width

152

throughout; ( 'ephalic ^egment scarcely longer than the 3 succeeding segments
(.nmbined: rostrum very long and evenly curved. Urosome nearly as long as the
anterior division, and tiijiering only very slightly behind, last segment about the
length of the preceding one. and having the anal opeivle finely spimilose. Caudal
rami quadrate in 1'oriu and slightly instrictcd at the base, each having, somewhat
beyond the middle of the outer edge, a notch carrying a slender seta and a short
spine, middle apical sctte of moderate length. Anterior antennas comparatively
short and gradually attenuated distally, 8-artieulate, 1st joint much the largest,
terminal part not attaining half the length of the proximal. Posterior antenna,'
comparatively less robust than in the '2 preceding species, outer ramus very nar-
row, with the middle joint extremely m : -iute and without any seta. 1st pair of
legs rather slender, outer ramus considerably exceeding half the length of the
inner, middle joint much the longest, terminal joint small, with only 3 claw-like
spines and a slender seta at the inner corner; inner ramus with the 2 outer joints
very short and suh"i|ual. apical claws rather unequal, the outer one being scarcely
half as long as the inner and nearly straight. Last pair of legs with the distal
joint large, oval in form, carrying 6 rather unequal setse, 4 of which issue from
the somewhat exserted and obliquely-truncated extremity; inner expansion of
proximal joint comparatively short, triangular, not nearly extending to the middle
of the distal joint, marginal seta. 1 5 in number, the outermost one very small.
Ovisacs rather short, extending, as a rule, only slightly beyond the middle of
the urosome.

Mulr of still more slender form than female. Anterior antenna' consider-
ably more elongated, and transformed in the usual manner. Spine attached to
the inner corner of the 2nd basal joint in the 1st pair of legs falciform, incurved
and obliquely cut of! at the tip. Inner ramus of 2nd pair of legs with the distal
spiniforni appendage of the outer edge peculiarly transformed, terminating in a
bro:id ^ecuriform lamella, apical spine replaced by an ordinary plumose seta.
La-t pair of legs very small, distal joint cordate in shape, with only 4 marginal
BetSB, the outermost but one very -mall, hair-like; inner expansion of proximal
joint very >light, with only 2 unequal seta 1 .

I'.ody of a liiiht yellowish colour with some of the segments bordered \\ith
ivddNi brown.

Length of adult female about 1 mm.

It'i //">//>. I cannot doubt that t he a bo\ e-descnhed form is that originally
recorded by Clans a> I )ucl ijlninis >///////>-. ami ^ub>eipieiitly mentioned by Prof,
lirady under the >ame name in his \\ell-kno\vn Monograph. The suggestion of
the latter author, that tlii- form, bcin;: 80 nearly related to DoctylopUS Str0mi ( />.

153

rix G. 0. Sars), ought perhaps more properly to be considered as merely a
variety of that species, is quite unintelligible to me. I consider, on the contain .
that the present form is so very different, both as regards its general appearance
and structural details, that it cannot even be placed in the same genus.

Occurrence. This is one of our commonest Harpacticoida, occurring rather
abundantly along the whole south and west coasts of Norway, from the Christiania
Fjord at least to the Trondhjern Fjord. It is not, however, a strictly littoral form,
but is only found in moderate depths among alga?.

Distribution. British Isles (Brady), coast of Bohuslan (coll. Oleve), Me-
diterranean at Nice (Glaus).

96. AmphiasGUs nasutus (Boeck).

(PI. XCV).
Dactylopus naxiitits, Boeck, M. S.

Syn : Dactylopus Stromi, var. arctica. Scott.

Specific Characters. Female. Body resembling somewhat in its general
appearance that of ^4. similis, though comparatively more strongly built and less
pronouncedly cylindrical in form. Cephalic segment comparatively larger and
broader. Rostrum likewise broader and less acute at the tip, which is abruptly
curved downwards. Urosome slightly tapering distally, with all the segments
coarsely spinulose at the hind edge ventrally and laterally, last segment shorter
than the preceding one. Caudal rami scarcely instricted at the base, quadran-
gular in form, notch of the outer edge occurring close to the tip. Anterior an-
tennae still shorter and stouter than in A. similis, but composed of 9 well-defined
articulations, of which the first 2 are much larger than the others. Posterior
antennae more strongly built, but otherwise of the very same structure as in tlir
above-mentioned species. 1st pair of legs likewise rather similar, but less slender
in form, differing moreover in having the terminal joint of the outer ramus more
expanded and armed with 4 strong claw-like spines in addition to the seta nf the
inner corner. Last pair of legs resembling in shape those of A. similis, tin nigh
having the distal joint comparatively broader, and the outermost seta of the inner
expansion of the proximal joint more fully developed. Ovisacs comparatively
larger, extending considerably beyond the middle of the urosome.

Male agreeing with that of .1. similis in most of the anatomical details,
but differing v 3r y conspicuously in the structure of the inner mum* "I" L'ml pair
of legs. The distal joint of this ramus is considerably dilated at the base, and

154

armed outside with an exceedingly strong spinitbnn appendage; while another
peculiar!}' transformed appendage projects from near the tip, and is connected witli
th<- base of the former by a narrow chitinous strip running along the under sur-
face of the joint, the freely projecting part of the appendage being folded abruptly
upon itself in a peculiar manner, and terminating in a very narrow upturned point.

Body in both sexes of a pale yellowish green colour, and generally filled
with numerous refracting oil-globules.

Length of adult female about 1 mm.

Remarks. -The above-described species is unquestionably identical with a
form recorded by Th. Scott from the Arctic Ocean under the name of J)({cti/lt>i<*

var. nrrtica. As this form in reality is very different from Dactylopus
i Cls. (- D. nilijnrix G. 0. Sars), I have felt justified in reviving for it a
M8name given to this form by the late Dr. A. Boeck. Its nearest ally is evi-
dently A. tiniUix, from which species it may be easily distinguished, however,
by its mo'-e robust body, the distinctly 9-articulated anterior antennae, and the
structure or the 1st pair of legs and that of the inner ramus of the 2nd pair in
the male.

()<-ft<rri'Hc<'. I have found this form occasionally off the west coast of
Norway at Christiansund and Aalesund in moderate depths among algae. Off the
Finmark coast, this species is much more frequently met with. I have myself
taken it at Hammerfest and Vadso, and in some samples taken by Mr. Xordgaard
at Repvaag in the Porsanger Fjord, and kindly sent to me for examination, this
form occurred rather abundantly.

Ditfrilitititiit. Arctic Ocean, off Franz Josef Land (Scott), and polar islands
of (-Jrinnell Land (2nd Fram Exited.).

!)7. Amphiascus minutus (Clans).
d'l. xcvh.

niiniifns. Cl;iiis, Die I'n-il.'hrnilni ( '. .prpncliMi. p. ll'd, I'l. XVI. li-s. II. 1").

Syn: I>losn,-i /.-, ulii/sxi.
Daclitl"i>nx I'nitiiriis/rix. S.'citt (in.) Chins).

c < 'htii-nrtt')-*. FrHtiilr. |!ody moderately slender and slightly attenu-
ated behind. (Vphalie segment about the length of the .'! -uccccding segments
combined: rostrum well drvchtped and of usual appearance. Urosome about, - :;
the length of the anterior dhiMuii of the body, last segment much shorter than the
preceding one. Caudal rami very short, being almost twice as broad as they are

J55_

long, and somewhat obliquely truncated at the tip, setae normal. Anterior an-
tennae rather slender and attenuated, 8-articulate, 4th joint considerably longer
than 3rd, and about equal in length to the 2nd, terminal part nearly half as
long as the proximal one. Posterior antennae with the outer ramus of moderate
size, middle joint well defined and setiferous. 1st pair of legs rather slender,
outer ramus slightly exceeding half the. length of the inner, and, as in the 4 pre-
ceding species, having the middle joint much larger than the others, last joint
small and armed with 3 claw-like spines and 2 geniculate setae inside the latter;
inner ramus with the 1st joint very slender, the other 2 quite short, subequal,
and as a rule 'bent outwards at nearly a right angle with the 1st, last joint
armed with a strong, distinctly pectinate claw and a slender geniculate seta inside
it. Natatory legs very slender, otherwise of normal structure. Last pair of legs
with the distal joint of moderate size and broadly ovate in form, with 6 not very
elongated marginal setae; inner expansion of proximal joint rather large, extend-
ing considerably beyond the middle of the distal joint, marginal setae 5 in number
and rather strong. Ovisacs comparatively large, extending to the end of the
urosome.

Male having the anterior antenna? transformed in the usual manner. 2nd
basal joint of 1st pair of legs forming, inside, 2 strongly chitinized dentiform pro-
jections in addition to the usual spine, which latter does not exhibit any differ-
ence from that in the female. Inner ramus of 2nd pair of legs with 2 closely
juxtaposed spiniform appendages outside near the tip, the latter unarmed. Last
pair of legs with the distal joint much smaller than in female, and sub-cordate in
form; inner expansion of proximal joint with only 2 unequal marginal setae.

Colour whitish, with a slight rosy tinge.

Length of adult female 0.64 mm.

Remarks. The above-described form is unquestionably identical with that
recorded by Prof. Brady as Dactylopus m'tnutus, Glaus. The description and
figures given by Glaus are certainly very scanty; but I believe that there is no
reason to doubt the correctness of Prof. Brady's identification. The form recorded
by Boeck as Diosaccus abijssi is this species, and this is also evidently the case
with the form described by Th. Scott from Franz Josef Land as JJurti/lnjm*
kngirostris Glaus. The present species is easily distinguished from any of the
4 preceding ones, both by its much inferior size and by the structure of the
anterior antennae and 1st pair of legs.

Occurrence. I have found this form occasionally in the Christiania Fjord,
as also off the south and west coasts of Norway in moderate depths among algae.

156

I)i*ti-il>/ifiou. British Isles (I'-rady). Heligoland (Clans), Fran/ Josef
Land (Scott).

98. Amphiascus imus (Brady).
(n. xrvii).

iiii'i. llr.-idy. .M.in.i-T:i]ili of Briti>li ('.ipi-ii.iila, vol. II. p. '-ft. I'l. XI, 111. liys. 1 14.

Sjurifii' Characters. Female. Body exceedingly slender and elongated,
sub-linear in form. with the anterior division scarcely broader than the posterior.
Cephalic segment about the length of the 3 succeeding segments combined: ros-
trum very long, lanceolate in form, with the tip acutely produced. Urosome a
little shorter than the anterior division, last segment about the length of the pre-
ceding one. Caudal rami very short, being almost twice as broad as they are
long, and obliquely truncated at the tip, inner corner more prominent than outer.
the 2 middle apical setae considerably thickened at the base, and distinctly spinu-
lose in their outer part. Anterior antennae very slender, 8-articulate, 2nd joint
the largest, 4th joint considerably longer and narrower than 3rd, terminal part
not nearly attaining half the length of the proximal one. Posterior antennae with
the outer ramus rather slender and elongated, middle joint well defined and seti-
ferous. 1st pair of legs comparatively slender, with the outer ramus about half
as long as the inner, middle joint scarcely longer than the 1st, terminal joint but
little smaller, and armed with 3 spines and 2 geniculate seta?; inner ramus with
the 1st joint long and narrow, more than twice as long as the other 2 combined,
last joint considerably longer than the 2nd. and linear in form, finely spinulose
outside, and carrying on the tip a slender claw, a somewhat longer seta, and a
small hair-like bristle inside the latter. Natatory legs rather slender and of normal
-tructure. Last pair of legs with the distal joint comparatively narrow, oblong
in form, with only 5 marginal seta?, the 2 apical ones slender, hair-like, the othor
3 rather small; inner expansion of proximal joint large, triangular, extending
considerably beyond the middle of the distal joint, marginal setae 5 in number,
and all well developed. Ovisacs very narrow and only slightly divergent.

Mii!>- of a narrow and slender form similar to that of the female, and having
the anterior antenna' transformed in the usual manner. 2nd basal joint of 1st pair
of legs forming, inside, .'} strongly chitinised dentiform projections in addition to
the u>iial xjiine. Inner ramus of 2nd pair of le-s considerably shorter than th-
outer, distal joint only slightly longer than the proximal one. and carrying out-
side near the tip 2 closely juxtapo-^-d spinjforin appendages of unequal si/e, the
proximal one being much the stronger. La-J pair of le^s rather unlike those in

ThaJestridae

Copepoda

Harpacticoida

PLIXXXT

G.O. 3ars. autogr. Norsk Lithgr. Offioin.

Dactylopoolella flava (Glaus)

Thalestridae

Copepoda

Harpacticoida

PI. rani

G .0. Sars, autogr.

Idomene forficata, Philippi

Norsk Liihgr. Officin.

ThaJestridae

Copepoda

Harpacticoida

pi.Lxxxm

'

..

,

/

?/

G .0. Sara. <* uiogr

Amenophia pe'ltata, Boeck

Norsk Lthgr. Officin.

Thaleslridae

Gopepoda

Harpacticoida

' ;:

*1

G.O. Sars. autogr.

lAmenophia peltata, Boeck

(continued )
2Amenophia pulchella, G.O. Sars

Norsk Liihgr. Officin.

Thalestridae

Copepoda

Harpacticoida

PLLXXXV

G .0. Sa rs. autogr.

Westwoodia nobilis (Baird)

Norsk Lithgr. Officin.

ThaJestridae

Copepoda

Earpacticoida

Pl.LXXXVI

G .0. Sars, autogr.

Westwoodia nobrlis (Baird
(continued)

Norsk Lithgr. Officin.

ThaJestridae

Copepoda

Harpacticoida

pi.mxvn

^-

G.O. Sars. autogr. Norsk Lithgr. Officm.

Westwoodibc assimilis, G.O.Sars.

ThaJestridae

Copepoda

Harpacticoida

piLsxxvnr

G.O. Sars, autogr.

Westwoodia minuta (Glaus)
Westwoodia py^maea (Scott)

Norsk Lithgr. Officin.

Diosaccidse

Copepoda

Haipacticoida

P1.13XXK

G.O. Sars. autogr. Norsk Lithgr. Officm.

Diosaccus tenuicornis,(Claus)

Diosaccidas

Copepoda

Harpacticoida

Pl.XC

G.O. Sars. autogr. Norsk Lithgi. Officin.

Diosaccus tenuicornis,(Claus)
(continued)

Diosaccidae

Copepoda

Harpacticoida

PIXCI

Jr

G.O. Sars. autogr. Norsk Liihgr. Officin.

Amphiascus cinctus (Glaus)

Diosaccidae

Gopepoda

Harpacticoida

G.O. Sars, autogr.

Amphiascus cinctus (daus)
(continued)

Norsk L'thgr. Officin.

Diosaccidae

Copepoda

Harpacticoida

PI.XCHI

G.O.Sara, au'togr. Nor3k Liih 9 r Offioin.

Amphiascus obscurus, G.O.Sars

Diosaccidae

Copepoda

Harpacticoida

pixcnr

; , j // ' I .

Llf/ lii v

G.O. Sars, auiogr. Norsk Liihgr. OfFicin.

Amphiascus similis. (Glaus)

Diosaccidae

Copepoda

Harpacticoida

G.D. Sars. autogr.

Amphiascus nasutus (Boeck)

Norsk Lrthgp. Offioin.

Diosaccidae

Copepoda

Harpacticoida

P1.XCVI

G.O. Sars, autogr. Norsk lithgr. Officin.

Amphiascus minutus ( (Claus)

AN ACCOUNT

OF THE

CRUSTACEA

OF

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS XIII & XIV

DIOSACCID^E (continued)

WITH 16 AUTOGRAPHIC PLATES

BERGEN

PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMERMEYER'S FORLAG, CHRISTIANIA

1906

157

female, distal joint short and sub-cordate in form, inner expansion of proximal
joint slightly produced, and carrying 2 setae and a short spine outside the latter.

Body in both sexes of a whitish colour, without any obvious pigmentary
ornament.

Length of adult female 0.77 mm.

Remarks. I cannot doubt that the above-described form is that origin-
ally recorded by Prof. Brady as Stenlielia nun, though the figure he gives of the
last pair of legs in the female does not exactly agree with my own drawings.
It unquestionably belongs to the present genus, and may easily be recognized by
its exceedingly slender and narrow body, the very long rostrum, and the shape
of the last pair of legs in the female.

Occurrence. I have met with this species occasionally both off the south
and west coasts of Norway in moderate depths among algse. The rostrum seems
to be more mobile in this species than in any of the others, being often found,
in preserved specimens, deflexed to such an extent, that it forms quite a right
angle with the axis of the body.

Distribution. British Isles (Brady).

99. Amphiascus Giesbrechti, G. 0. Sars, n. sp.

(PL XCVIII).
Syn: Stenhdia iia, Griesbrecht (not Brady).

Specific Characters. Female. Body rather slender and somewhat attenu-
ated behind, with the anterior division considerably broader than the posterior.
Cephalic segment of moderate size; rostrum narrow triangular in form, and com-
paratively shorter than in A. imus. Epimeral plates rather small and rounded
behind. Urosome not nearly attaining the length of the anterior division, anal
segment somewhat shorter than the preceding one. Caudal rami of moderate size
and quadrangular in form, being about as long as they are broad, and transversely
truncated at the tip; innermost but one of the apical setoe peculiarly dilated at
the base, forming outside, immediately behind the articulation, a very conspicuous
bag-like swelling protruding over the base of the adjacent seta. Anterior antennae
moderately slender and gradually attenuated distally, 1st and 2nd joints the
largest and of about equal size, 4th joint longer than 3rd, terminal part con-
siderably exceeding half the length of the proximal part. Posterior antennae with
the outer rarnus rather short, middle joint very small and without any seta. 1st
pair of legs with the outer ramus considerably longer than the 1st joint of the

21 Crustacea.

158

inner, middle joint about the length of the 1st. terminal joint a little longer and
armed with I spines and a slender geniculated seta inside them ; inner ramus with
tlie 1st joint not much longer than the other 2 combined, last joint linear in form

and t \\ice as long as the L'nd. carrying a slender claw, a somewhat longer seta,
and a -mall hair-like bristle. Natatory legs resembling in structure those in .1.
imus; middle joint of inner ramus in .'!rd pair of legs. ho\\ever. like that in i^nd
pair, with L ; seta' inside. Last pair of legs with the distal joint oblong oval in
form, carrying H marginal setse, .') outside, one inside, and ~2 very slender ones
at the tip: inner expansion of proximal joint narrow triangular in form and ex-
tending almost as far as the distal joint, marginal setie 5 in number. Ovisacs
less narrow than in A. nun.--.

('lour light yellowish grey.

Length of adult female 1.1G mm.

lit iniif/,:--. The above-described form is unquestionably that recorded by
|r. (iiesbrecht as Sliiiluim iiihi. It is. however, most certainly distinct from
I'.radv's species, differing, as it does, both in si/e and in several of the anatomi-
cal details. ( )m- character which distinguishes the present species in a marked
(b'gree. and \\hidi is well described by \h'. Griesbrecht, is the peculiar bag-like
dilatation nf the largest of the caudal seta;, a feature which ensures the immediate
recognition of this species from any of the others known.

Occurrence. -Only a solitary, but well preserved female specimen of this
form lias hitherto come under my notice. It was taken many years ago oil' the
\\est coast of Norway, the exact locality not being stated. 1 )

l)'i>i,-il>tii'inn.- -Ray of Kiel (Giesbrecht).

K"i. Amphiascus propinqvus, (4. o. Sars. n. sp.

(PL \c|\).

N//.7-///V Clnii-iirli /.-. l'\ mull. l>ody moderately slender and only slightly
attenuated behind. ('ephalic segment about the length of the 4 succeeding seg-
ment- eombined: rostrum well de\eloped. lanceolate, extending nearly to the end
of the L'nd joint of the anterior antenna'. I rosonie almost attaining the length
of the anterior division, last segment fully as long as the preceding one. Caudal
rami short, i|iiadrani:iilar. broader than they are Ion-, the -J middle apical seta'
only slightl\ dilat.'d at the base. Anterior antenna' slender and attenuated.
s-articulate. the first 'J joints much the largest. Ith joint nearly twice as long as

tins <iinilii< ,-iii;lllv ill l''li-kk<T"i. si. nlli c.in^t ..I' N'..r\v:i\.

159

the 3rd, terminal part about half the length of the proximal one. Posterior
antennae with the outer rum us distinctly 3-articulate, middle joint well defined
and setiferous. 1st pair of legs with the outer ramus shorter than the 1st joint
of the inner, terminal joint about as long as the middle one, and armed with 2
spines and 2 geniculated seta?; inner ramus with the 1st joint very slender and
almost 3 times as long as the other 2 combined, last joint linear and twice as
long as the 2nd, tipped with a slender claw, a rather long seta, and a hair-like
bristle. Natatory legs about as in A. imus. Last pair of legs also of a rather
similar appearance, the distal joint being narrow oblong in form, but with 3
instead of 2 setae outside; inner expansion of proximal joint comparatively short,
triangular, extending scarcely beyond the middle of the distal joint. Ovisacs of
moderate size and somewhat more divergent than in A. nun*.

Male with the 2nd basal joint of the 1st pair of legs produced inside to
3 blunt spiniform projections. Inner ramus of 2nd pair of legs resembling in
structure that in the male of A. imus. Last pair of legs likewise of a very
similar appearance.

Colour whitish, with a faint yellowish tinge.

Length of adult female 0.57 mm.

Remarks. This species is closely allied to A. imus, but is of smaller
size and less slender form of body. It moreover differs somewhat in the structure
of the 1st and last pairs of legs.

Occurrence. Some few specimens of this form were found last summer
off the south coast of Norway, at Ris0r and Lillesand.

101. Amphiaseus longirostris (Glaus).

(PI. & CI).
Y Dactylopus longirostris, Glaus, Die freilebenden Copepodeu, p. 127, PI. XVIII, li^s. 4 6.

Syn : Diosaccus longirostris, Boeck.
Dactylopus longirostris, var. arctica, Scott.

Specific Characters. Female. Body moderately robust and slightly at-
tenuated behind. Cephalic segment comparatively large and deep, rostrum rather
prominent and evenly curved, terminating in an acute point. Urosome shorter
than the anterior division, with the hind edge of the segments finely spinulose
ventrally and laterally. Caudal rami quadrangular, being about as long as they
are broad, innermost but one of the apical seta? exhibiting near the base a con-
spicuous bulging outside, overlapping the adjacent seta; spine of outer corner

160

rather strong, iniirrinost seta very small and hair-like. Anterior antenna 1 slender
and attenuated. H-articulate. 4th joint more tlian twice as long as the 3rd, terminal
part exceeding halt the length of the proximal one. Posterior antenna,' with the
outer ramiis verv narrow and composed of only '1 joints, the middle one not
being defined. Oral parts quite normal. 1st paii- of legs with the outer ramtis
nearly as Ion-' as the 1st joint of the inner, last joint scarcely shorter, hut nar-
rower than the middle one. and armed with I spines and inside them with a geni-
mlated seta; inner ramiis with the 1st joint very narrow and more than twice as
long as the other '2 combined, last joint linear and about twice MS long as the
2nd. apical daw rather strong and distinctly denticulate on the one edge. Na-
tatory legs well developed and of normal structure. Last pair of legs with the
distal joint oval in form and provided with li marginal seta', the 2 apical ones
\ery -lender: inner expansion of proximal joint, rather hroad and obliquely trun-
cated at the end, extending beyond the middle of the distal joint, marginal setsc
"> in number, the 2 innermost ones spiniform. minutely bifid at the tip. Ovisacs
comparatively large and somewhat diverging.

.1A//' with the 2nd basal joint of the 1st pair of legs produced inside to 2
or 3 strong spiniform projections, in front of which is a small knob-like promin-
ence. 2nd pair of legs with the 2 first joints of the outer ramus considerably
produced at the outer corner, and having the spines, especially that of the 2nd
joint, much coarser than in female; inner ramus transformed in the usual manner.
Last pair of legs, as usual, smaller than in female, with the inner expansion of
the proximal joint conical in form and carrying 2 rather thick setae on the tip.

Hody of a light yellow colour, with a more or less distinct reddish tinge;
intestine generally dark-coloured.

Length of adult female 0.80 mm.

li'< murk*. It seems to me rather questionable if the above-described form

i- in reality that originally recorded by Clans as / >ni-l//lii/n<s InHi/inixtri*. It is

ho\\e\e| beyond doubt that lloeck's I )'n^ilrriis /r///</// W/'/x is the present species,

aa al-o the form recorded by Th. Scott from Kinmark as DactylopUS longirostris^

\ar. m-rlirii. Kor this reason, and as the description and figures given by Clans
arc too imperfect to admit of an\ certain identification. 1 think that the specific

name longirOStrii ought more properly to be applied to the present species. The
Sl<nliilin ln>t<i'ii-<i*tr'ix of Norman A Scott is a \.T\ different species; and as it
belongs to thr same vims MS Claus's specie-, its specific name must be altered.

Occurrence. I have met with this form in several places both on the
south and wesl coasts of Norway: and .Mr. Scott also records it from the Finmark
Coast. It generally occurs in depths ranging from 20 to r>n fathoms.

/)ixli-iliittii>n. '! Heligoland M'laiis), British Isles (Scott).

161

102. Amphiaseus tenuiremis (Brady).

(PI. Oil).
Dactylopus tenuiremis, Brady, Monogr. Brit. Copepoda, p. 115, PL LVI, figs. 12 18.

Specific Characters. Female. Body comparatively short and stout, some-
what depressed in front, and slightly attenuated behind. Rostrum rather large,
lanceolate. Urosome much shorter than the anterior division, anal segment not
quite as long as the preceding one. Caudal rami short, broader than they are
long, middle apical setse moderately thickened at the base. Anterior antenna?
slender and attenuated, 8-articulate, 4th joint twice as long as the 3rd, terminal
part very narrow and about half the length of the proximal one. Posterior an-
tennse with the outer ramus distinctly 3-articulate, middle joint well defined and
setiferous. 1st pair of legs comparatively strongly built, outer ramus, however,
as usual, small, scarcely attaining half the length of the inner, and having the 3
joints of about equal size, the last one carrying 3 spines and 2 geniculated setse;
1st joint of inner ramus rather large and slightly curved, being almost 4 times
as long as the other 2 combined, last joint not much longer than the 2nd and
tipped with an unusually strong and evenly curved claw-like spine, a slender seta
and a very small hair-like bristle. Natatory legs rather slender, but otherwise
of normal structure. Last pair of legs with the distal joint narrow oblong in
form, tapering towards the end, and densely ciliated both outside and inside,
marginal setse rather unequal and 6 in number; inner expansion of proximal joint
triangular, extending somewhat beyond the middle of the distal joint, marginal
setae rather elongated.

Male exhibiting the usual sexual differences from the female.

Body whitish, with a more or less distinct reddish tinge.

Length of adult female 0.63 mm.

Remarks. This species was recorded by Messrs. Brady and Robertson as
early as the year 1875, and was subsequently described and figured (though rather
imperfectly) by the first-named author in his well-known Monograph. It is a true
Amphiaseus , and may be easily distinguished from most other species of that
genus by its comparatively short and stout form, and by the structure of the 1st
and last pairs of legs.

Occurrence. I have found this form in considerable abundance in several
places both on the south and west coasts of Norway, in depths ranging from 10
to 30 fathoms. It is also recorded by Mr. Scott from the Finmark coast.

Distribution. British Isles (Brady), Arctic Ocean, off Spitsbergen and
Franz Josef Land (Scott).

I',!'

!".'>. Amphiascus parvus, u. <>. Sars. n. sp.

ii-i. in.

S/nn/ir Characters. Female. Body modcrateK slender, sublinear in form,
with tlir anterior division not inucli broader tlian the posterior. Ixostrum o|
moderate si/.c and (if tin- usual ibrm. Caudal ranii very short, much broader
than thc\ are long, middle apical -et;e slightly thickened at the base. Anterior
antenna' somewhat Less -lender than in the preceding species. Ith joint only little
longer than .'!rd. terminal part not attaining half the length of the proximal one.
1'oMcrior antenna' \vith the miter ramiis ^Imrter than the terminal joint of the
inner. its middle joint \ery small and without an\ seta. 1st pair of legs with
tin- outer ramiis extending but little beyond the middle of the 1st joint of the
inner, its middle joint of about the same si/.e as the 1st, and having no seta inside,
last joint somewhat smaller and armed with 3 strong spines and 2 geniculated
seta-: 1st joint of inner minus very slender, straight, being almost 4 times as
lon:{ as the other '2 combined, last joint not much longer than the 2nd, apical
daw of moderate length and almost straight. Natatory legs rather slender, ter-
minal joint of outer rainus in the 2nd and .'jrd pairs with only a single seta
inside. Last pair of legs with the distal joint broadly ovate in form and car-
rying 6 marginal setae, the 2 apical ones very slender and quite smooth; inner
expansion of proximal joint comparatively short, triangular, not extending to tin-
middle of the distal joint. Ovisacs of moderate size, and containing a limited
number of rather large ova.

Colour not yet ascertained.

Length of adult female <).4<i mm.

li'i nitii'l,'*. This new species somewhat resembles in its general appear-
ance A. Hiniittii*. but is of much smaller si/.e. and may nioreo\er be distinguished
by the less slender anterior anteniue and by the structure of the le--.

Occurrence.- Some few female specimen^ of this form were selected from

samples taken last summer oil the south coast of Norway, at K'isor and Lilh-sand.

hii. Amphiascus debilis (Giesbr.).

in. \civi.

I till llflii/ill-, il, lulls. ( ', ji -I.I rc||l. |>jr |'|vili'l>rl|i|f|| ( ' '|"'|'< ulc'll il'T Kil'llT I 1 '. .| I I'l 1 1 ' . |l. I L'J (lIUIIM'l

n: />in/i//iijiiis

S/,,ci/i<- ( 'Itni'iii-li />. /''linn//. Hotly moderately slender, sublinear in form.
alino>| of uniform width throughout. li'ostnim rather prominent, cttnically

tapered distally. Urosome with the segments finely spinulose at the hind margin
ventrally and laterally, last segment much shorter than the preceding one. Caudal
rami exceedingly short, being about twice as broad as they are long, middle
apical setae slightly thickened at the base, seta of outer corner unusually strong,
spiniform. Anterior antennae comparatively short, 8-articulate, 4th joint scarcely
longer than 3rd, terminal part not attaining half the length of the proximal one.
Outer ramus of posterior antennae with the middle joint very small and without
any seta. Oral parts quite normal. 1st pair of legs with the outer ramus ex-
tending somewhat beyond the middle of the 1st joint of the inner, middle joint
without any seta inside, last joint of about the same length, and carrying on the
tip only 2 spines and 2 geniculated- setae ; 1st joint of inner ramus slender, linear,
and about twice as long as the other 2 combined, last joint twice as long as the
2nd, apical claw slender and nearly straight. Natatory legs with the rami very
narrow and the setae of the inner edge much reduced in number: 1st joint of
outer ramus in all pairs without any seta inside; last joint of same ramus in
2nd pair having the inner edge also quite smooth, and in the 2 succeeding
pairs carrying only a single seta inside; last joint of inner ramus in 2nd and
4th pairs with a single seta on the inner edge, in 3rd pair with 2 setae. Last
pair of legs with the distal joint oval in form, and provided with only 5 marginal
setae, that issuing from the tip being very slender and quite smooth; inner ex-
pansion of proximal joint rather large, extending about as far as the distal joint,
marginal setae rather coarse and 5 in number. Ovisacs comparatively large, but
containing a rather limited number of ova.

Male with the anterior antennae transformed in the usual manner. 2nd
basal joint of 1st pair of legs produced inside to 2 strongly chitinized diverging
projections. Inner ramus of 2nd pair fully as long as the outer, distal joint pro-
duced at the end to a strong mucroniform projection not denned from the joint.
Last pair of legs much smaller than in female, with only 2 setae on the inner
expansion of the proximal joint.

Body of a whitish colour, with a slightly reddish tinge, intestine generally
of a dark violaceous hue.

Length of adult female 0.46 mm.

Remarks. This form has been very minutely described and figured by
Dr. Giesbrecht as a species of the gen. Dactylopus. It belongs, however, beyond
doubt to the genus Ampluascus, as here defined, having, like the other species,
2 ovisacs. The species is chiefly characterised by the comparatively short anterior
antenna?, and the considerable reduction in the number of the natatory setae on
the legs.

I ha\e met with tliis small species in several places on the

-i >iilh and west coast> n|' Nnr\\;iy. from the (Jhristiania Fjord at any rate up to
the Trondlijem Kjord. It occurs here and there, together with other species of
the L'eniis, in moderate depths aimm^ alga- and llvdmida.

t. Hay uf Kiel (( iie-|,i -edit), Scottish coast (Scott).

i ( '">. Amphiascus pallidus, G. 0. Sars, u. sp.

(I'l. CV).

c Characters. l''<mnl/'. Body comparatively robust, with the anterior
division somewhat broader than the posterior, and slightly depressed. Rostrum
rather broad at the base, triangular. Urosome much shorter than the anterior
division, and having the segments densely spinulose at the hind edge ventrally
and laterally. Caudal rami short, a little broader than they are long, the jj
middle apical seta> only slightly thickened at the base. Eye not visible in
the living animal. Anterior antenna- rather slender, 4th joint scarcely longer
than :>rd, terminal part exceeding half the length of the proximal, and with
none of the setse ciliated. Posterior antennae with the outer ramus scarcely
as long as the terminal joint of the inner, middle joint very small and with-
out any seta'. 1st pair of legs rather strongly built, outer ramus extending
beyond the 1st joint of the inner, its middle joint somewhat larger than the other
-2, and with a well-developed seta inside, last joint armed with 3 spines and 2
ni'iiiculated sette; 1st joint of inner ramus somewhat exceeding the length of the
other 2 combined, last joint more than twice as long as the 2nd. apical ela\\
rather strong. Natatory legs well de\ doped, with the full number of setse. Last
pair of legs \\ith the distal joint rounded oval in form, carrying 6 marginal setae,
l of which, attached to the tip, are very narrow and quite smooth; inner expan-
sion of proximal joint extending somewhat beyond the middle of the distal joint.
and obliquely truncated at the tip. marginal seta- 5 in number. Ovisacs of mo-
derate size, containing numerous ova.

MX/I \\itli the L J nd basal joint of 1st pair of legs produced inside to L ;
blunt spines, in front of which is a small knob-like prominence. 'Jiid pair of legs
with the spines of the outer ramus much coarser than in female, inner ramus
much shorter than the outer and transformed in the usual manner, distal joint
Considerably dilated in the middle, one of its spinit'orm appendages being exceed-
ingly -ti"H'j. Last p.-ijr of legs much smaller than in female, distal joint rather

165

narrow, inner expansion of proximal joint triangular and provided with only 2
spiniform seta? at the tip.

Body of a whitish colour, with a very faint yellowish grey tinge.

Length of adult female 0.71 mm.

Remarks. This new species is especially distinguished by its compara-
tively rohust and pale-coloured body, as also by the apparent total absence of
eye. In the anatomical details it on the whole rather resembles the succeeding
species, though differing conspicuously in some few points.

Occurrence. I found this form many years ago at Christiansund. west
coast of Norway, in a depth of 50 60 fathoms, muddy bottom.

106. Amphiascus abyssi (Boeck).
(ri. cvi).

D(tc1//l<>]>u* abyssi. Boeck, Nye Slsegtev og Arter af Saltvandscopepoder. Chr. Vid. Selsk.

1872, p. 56.

Specific Characters. Female. Body rather robust and only slightly at-
tenuated behind, anterior division scarcely at all depressed. Cephalic segment
broadly rounded in front, rostrum of moderate size, terminating in an acute point.
Epimeral plates of the 3 succeeding segments acutely produced behind; last seg-
ment narrower than the preceding one. Urosome much shorter than the anterior
division, and having the segments coarsely spinulose at the hind edge ventrally
and laterally, last segment shorter than the preceding one. Caudal rami resem-
bling in form those in A. pallidus, though armed both inside and outside with
small spinules, the 2 middle apical setse distinctly spinulose and slightly thickened
at the base. Eye well developed, with the pigment of a very pale yellowish
hue. Anterior antennae remarkably short and stout, much curved and densely
clothed with setse, some of which are very strong and coarsely ciliated, 4th joint
scarcely longer than 3rd, and very obliquely truncated at the end, terminal part
about half the length of the proximal one, with the first 2 joints remarkably
short and broad. Posterior antennas with the outer raraus rather large, exceed-
ing in length the terminal joint of the inner, but otherwise of much the same
structure as in A. pattidus. 1st pair of legs somewhat less strongly built than
in that species, outer ramus scarcely longer than the 1st joint of the inner, and
densely spinulose outside, its middle joint shorter than both the 1st and last,
and provided inside with a rather large ciliated seta, last joint armed with 3
spines and 2 strong ciliated seta?, which are not geniculated; 1st joint of inner
ramus about the length of the other 2 combined, last joint very slender, linear

22 Crustacea.

L66

being more than twice as long as tin- 2nd. apical claw comparatively short. Na-
tatory le^s of almost exacth tin- same structure as in J. /^///r//'x. Last pair of
legs also of a very similar shape, though tin- distal joint is more oblique and
the inner expansion of the proximal joint comparatively broader, marginal seta-
rather short and very distinctly ciliated. Ovisacs unusually small, each contain-
ing, as a rule, only 2 ova.

M'il< with the inner ramus of the mandibular palp peculiarly transformed,
vehicular in shape, with only a single small seta on the inner edge. 2nd basal
joint of 1st pair of legs produced inside to an obtuse conical prominence, beyond
which is a comb-lik' series of ~> blunt spines. Inner ramus of 2nd pair of legs
transformed in the usual manner. Last pair of legs much smaller than in female,
distal joint broader than in the male of .1. jmUiiliix. and the end obliquely
truncated.

( '"lour dark grey.

Length of adult female 1.2d mm.

. This form was erroneously referred by Boeck to the genus
AS proved by the double o\isac and the structure of the several
appendages, it is however unquestionably a true Amphiascus, nearly related to
.1. iniHiilit*. though easily distinguished from it by its much larger size and the
-hort and stout anterior antenna 1 , with their coarsely ciliated seta-.

Orcm /< HIT. This is a true deep-water species, and thus fully deserves
the specific name given to it by Boeck. I have found it occasionally in the upper
part of the ( 'hristiania Fjord and also in several places on the west coast of
Norway, in dept'.is ranging from -Id to l"d fathoms, muddy bottom. It moM's
with great dexterity through the loose mud, and very seldom leaves the bottom.

107. Amphiascus hispidus (Norman).

H'l CVII ,v ( Vllli.
i'i lii^/ii'ltl. l'.r:iil\. .M"i:"'T. I'.ril. ( '. I|M'[K H|;I. ].. .'i'J. I'l. XI. II. li--. I II.

.^/irri/ii- ('htiriirliT*.--l' J <-ninl,-. I'.ody rather slender, cylindric in form.

with the internments stron-lx dnt inised. Cephalic segment narrowly rounded in

liont. and not very deep; rostrum rather prominent and somewhat curved. Kpi-

meral plate- of the :! succeeding segments >mall and rounded behind: last

segment scarcely narrower than the preceding one. Urosome nearly as long

the anleiior division ami having the segments vi-ry >harply delined. genital

inent distinelh divided in the middle, and. like the 2 succeeding segments,

167

clothed laterally, at some distance from the hind edge, with an oblique series of
small spinules; last segment much shorter than the preceding one. Caudal rami
unusually produced, being rather longer than they are broad, and oblong quadran-
gular in form, apical setse comparatively short and distinctly spinulose, the outer
median seta with a conspicuous bulging on the outer side near the base. Anterior
antennae not much elongated, 8-articulate, 4th joint somewhat longer than 3rd,
terminal part scarcely attaining half the length of the proximal. Posterior antenna;
with the outer ramus rather small, middle joint exceedingly minute and without
any seta. Oral parts quite normal. 1st pair of legs with the outer ramus some-
what longer than the 1st joint of the inner and densely spinulose outside, middle
joint without any seta inside, last joint shorter than the middle one and carrying
on the tip 2 claw-like spines and 2 geniculated setse; 1st joint of inner ramus
twice the length of the other 2 combined, last joint somewhat longer than the
2nd, apical claw rather strong, nearly straight, and distinctly spinulose on one of
the edges. Natatory legs with the setse much reduced in number. 1st joint of
outer ramus in all the pairs without any seta inside, terminal joint of same ramus
in 2nd pair likewise without any setae on the inner edge, and in the 3rd pair
with only a single seta; terminal joint of inner ramus in the 2nd and 4th pairs
with only one seta inside. Last pair of legs with the distal joint rounded in
form and carrying 5 rather slender marginal setse, inner expansion of proximal
joint extending almost as far as the distal joint, marginal setse 5 in number.
Ovisacs narrow oblong and only slightly divergent. Spermatophore attached to the
genital segment unusually large, extending to the end of the antepenultimate
caudal segment.

Male, as usual, of smaller size than female, and having the urosome di-
stinctly 5-articulate and somewhat thicker than in that sex. Anterior antennse highly
chitinised and distinctly prehensile, with the 4th joint strongly dilated. 1st pair
of legs with the 2nd basal joint armed inside with a very strong deflexed tenon-
like projection, blunted at the tip and of a very dark colour, 1st joint of inner
ramus considerably thicker than in female, and having inside close to the base a
darkly-coloured nodiform prominence. Inner ramus of 2nd pair of legs with the
distal joint highly chitinised and projecting at the end in a strong bayonet-shaped
process, on the inner side of which a more slender spiniform appendage is attached.
Last pair of legs much smaller than in female, distal joint rather narrow, with
2 of the outer setse spiniform, inner expansion of proximal joint very slight, with
2 unequal spines and numerous small spinules.

Colour dark yellowish grey.

Length of adult female 1.15 mm., of male 0.98 mm.

168

lt'< ///"//,>. --This form was first detected by Canon A. M. Norman, and
\\as subsequently tl. -si T\ bed and figured by I'mf. lirady in his well-known Mono-
graph under tin.- name originally propoM d by Norman. It is a very distinct and
asily recogni/.able species, being especially distinguishable by the slender cylin-
drical form of the body, the highly chitiniscd integuments, and the unusual pro-
duction of the caudal rami. It is also of rather large si/.e as compared with
the other species of this genus.

Occurrence.] have found this form not (infrequently at Aalesund and
< 'hristiansund. on the west coasl of Norway, in moderate depths among alga.-. It
also occurs oil the Finmark coast, several specimens ha\ing been taken many
years ago at Vadso.

Distribution. British Isles (Brady).

lO.s. Amphiascus affinis, <T. o. Sars, n. sp.

(PJ. (IX).

>/r///V Characters. Female. General form of body similar to that of
. 1. ln.<i>nl,is. being rather slender, subcylindrieal. Kostrum of moderate si/e and
blunted at the tip. Caudal rami short, being considerably broader than they are
long, the '2 middle apical seta 1 remarkably strong, dark-coloured and considerably
thickened at the base. Anterior and posterior antennsc of much the same struc-
ture a- in .1. h't^ji'tilii.--. 1st pair of legs likewise of a very similar appearance,
though having the outer 2 joints of the inner ramus shorter and nearly equal
in si/e. Natatory legs exhibiting a reduction in the number of the seta? similar
to that found in the above species. Last pair of legs with the inner expansion
of the proximal joint comparatively shorter than in .1. ///>-ym//'N. extending <>nl\
-lightly he\ond the middle of the distal joint, which latter exhibits a rounded
form very similar to that in the above-named species. ()\i>acs somewhat more
divergent.

Colour not yet a-cci taincd.

Length of adult female 0.82 mm.

/.' //"'//>. -This fin-Hi closely resembles . |. lii^/iiilns. both as regards general
appearance and structural details. It is however of rather inferior si/e. and is
moivmer easily distinguished by the form of' the rostrum and the much shorter
caudal rami.

Occurrence. Some lew specimens of this form, all of the female B6X,
were collected from -amples taken during the summer of 1 '.MI.') at K'isor and Lille-
sand, on the south coast of Norway.

169

109. Amphiaseus intermedius (Scott).

(PI. CX).

iitfi'i-iiu'dut, Tli. Scott, Marine Invertebrata of Loch Fyne, 15th Ann. Bep. of the Fisherj
Board for Scotland, p. 169, PI. II, figs. 1021.

Specific Characters. Female. Body much shorter and stouter than in the
2 preceding species. Cephalic segment rather broad and evenly rounded in front;
rostrum distinctly bifid at the tip. Caudal rami much broader than they are
long, apical seta3 remarkably short and moderately thickened at the base. An-
terior antennae of a structure similar to that in the 2 preceding species, though
having the last joint somewhat larger, nearly equal in length to the 3 preceding
joints combined. Posterior antennae scarcely differing in their structure from
those in the above-mentioned species. 1st pair of legs likewise of a very similar
structure, outer 2 joints of inner ramus rather short, together scarcely attaining
half the length of the 1st. Natatory legs almost exactly as in the 2 preceding
species. Last pair of legs with the distal joint somewhat tapered distally and the
marginal setae comparatively shorter than in those species; inner expansion of
proximal joint triangular, extending slightly beyond the middle of the distal joint.
Ovisacs rather large and diverging considerably.

Male with the 2nd basal joint of 1st pair of legs produced inside to a
highly chitinized tenon-like projection similar to that found in the male of A. his-
l>idux, the tip of the projection, however, being less blunted. Inner ramus of 2nd
pair of legs transformed in a manner very similar to that in the male A. Inx-
ffiditx, the bayonet-shaped terminal projection being, however, somewhat shorter
and having on the outer side 2 strong serrulations not found in that species.

Colour yellowish grey.

Length of adult female 0.74 mm.

Remarks. This is unquestionably the species recorded by Th. Scott in
the above-named paper as titenhelia interim' dm. Though closely related to the
2 preceding species, it may be at once distinguished from either of them by its
much shorter and stouter body, as also by the distinctly bifid rostrum and the
unusually short caudal setae.

Occurrence. Some few specimens of this form were taken at Levanger,
on the Trondhjem Fjord, and at Kopervik, on the west coast of Norway, in depths
ranging from 20 to 30 fathoms.

Distribution. Scottish coast (Scott).

170

lln. Amphiaseus typhlops, u. <>. Sars, n. sp.

(I'l. (XI).

Specific Characters. Female. Body very slender, sublinear in i'unu. \vith
the '2 chief division* m-arly equal in length. Rostrum inucli attenuated, termin-
ating in an acute point. Caudal raiui unusually prolonged, being fully twice as
long as they are broad, apical seta' <il' moderate length and only slightly thick-
ened at the hasr. K\e \\liollv ahseiit. Anterior antenna; moderately elongated
and less attenuated than ill most other species, 8-articulate. 4th joint not much
longer than ,'ird. terminal part scarcely attaining half the length of the proximal.
Posterior antenna 1 with the outer ramiis ahout the length of the terminal
joint of the inner, middle joint very small and without any seta. Oral parts
normal. 1st pair of le.^ r s \\ith the outer minus about as long as the 1st joint of
the inner, middle joint with a well-developed seta inside, last joint somewhat
longer than the middle one. oblong oval in form, and armed with 4 slender spines
and a still more slender ciliated seta inside the spines; 1st joint of inner ramus
about the length of the other 2 combined, last joint very slender, linear, 3 times
as long as the 2nd, apical claw very long and evenly curved. Natatory legs with
the rami rather narrow and with a larger number of seta? than in the 3 preceding
species, outer apical seta of inner ramus spiniform. Last pair of legs with the
distal joint very narrow, oblong in form, and carrying <> rather slender marginal
setae; inner expansion of proximal joint narrow triangular, and extending to about
the middle of the distal joint, marginal seta- 5 in number. Ovisacs comparatively
small, with a very limited number of ova.

Ma/'' with the 2nd basal joint of 1st pair of legs produced inside at the
base to a small knob-like prominence, beyond which is a comb-like series of 4
blunt spines. Inner ramus of ^nd pair of legs rather slender, being fully as Ion-
as the outer, and transformed in the usual manner, the distal joint carrying out-
side, at some distance from the tip. '1 spiniform appendages, the outer of which
is shorter ;ni(l thicker than the inner. Last pair of legs, as usual, smaller than
in female, with the inner expansion o| the proximal joint obtusely conical in form,
and earning on the tip ~1 spiniform seta- of somewhat unequal length.

('olour whitish.

I <'iii;tli of adult female li.'.i.i mm.

Remtt'i This is a \rr\ distinct and easily recogni/able species, being

especially characterised by the \ery slender linear form of the body, the narrowly
tapered rostrum, and the unusually prolonged caudal rami. Not the slightest
trace of an eye could be detected in the living animal.

171

Occurrence. Only 2 specimens, male and female, of this form have hitherto
come under my notice. They were taken at the same time in the upper part of
the Christiania Fjord from a depth of 30 40 fathoms, muddy bottom. 1 )

in. Amphiaseus attenuate, G. 0. Sars, n. sp.

(PI. (JXII).

ic Characters. Female. Body moderately robust and very conspi-
cuously attenuated behind, exhibiting in the dorsal view of the animal a somewhat
clavate form. Cephalic segment very large and broad, evenly rounded in front;
rostrum rather broad, triangular. Urosome much narrower than the anterior
division and evenly tapering behind, last segment about the length of the pre-
ceding one. Caudal rami quadrangular in form, being a little broader than they
are long, the 2 middle apical setffi, but especially the inner one peculiarly ex-
panded near the base. Anterior antennae rather slender and composed of 9 well-
defined joints, the first 4, composing the proximal part, being nearly equal in
length, terminal part comparatively short, scarcely exceeding l /- A of the proximal
one. Posterior antennae likewise of rather slender form, outer ramus very small
and composed of only 2, not very distinctly defined joints. Oral parts, on the
whole, normal. 1st pair of legs differing somewhat in structure from those in the
other species, outer ramus much shorter than the 1st joint of the inner, its
largest joint being the middle one, with a comparatively short seta at the end
inside, last joint rather small and armed with 3 spines and 2 geniculated setee;
1st joint of inner ramus very slender, linear, being about 3 times as long as the
other 2 combined, last joint not much longer than the 2nd and slightly expanded
distally, carrying on the tip 2 strong claws and a small hair-like bristle inside
them. Natatory legs rather strongly developed, with the full number of setae.
Last pair of legs with the distal joint oval in form, and carrying 6 comparatively
short marginal seta?; inner expansion of proximal joint rather broad, extending
to about the middle of the distal joint, marginal setse 5 in number, spiniform,
the outermost one very small. Ovisacs of moderate size.

Colour whitish, with rosy ovaries, and the ovisacs generally of a dark
purple hue.

Length of adult female 0.87 mm.

Remark*. This form differs in some respects rather conspicuously from
the other species, especially as regards the structure of the two pairs of antenna 1

a ) Found occasionally this summer at Farsund. south coast of Norway.

172

and the 1st pair of legs: and it ought perhaps more properly to be referred to
the genus /'.,-, itlinliti*nn-t(* recently established by Th. Scott. The oral parts.
however, which in this genus are said to he built upon the same type as in
lhn*ii.n-,is, are quite normal in tlie present species, and the inner ramus of the -1th
pair of legs is composed of :! well-defined joints.

Orrtn-rriirr, Only 2 female speeimens of this form have hitherto come
under my notice. They were found in a sample taken at Kopervik, on the west
roast ( if Norway. 1 )

Amphiaseus phyllopus, G-. 0. Sars, n. sp.

il'l. CXIII).

fa- riHii'iirti-r*. fr'iintlt . Body comparatively short and stout, only
sliirhtly tapered behind. Cephalic segment rather large, fully as long as the 4
succeeding segments combined, and obtusely rounded in front; rostrum prominent,
obtusely acuminate at the tip. Urosonie not much shorter than the anterior di-
vision, segments sharply defined and coarsely spinulose at the hind edge ventrally
and laterally, genital segment large, quadrangular, imperfectly divided in the
middle, last segment somewhat shorter than the preceding one. Caudal mini
comparatively large, quadrangular in lorm, being nearly as long as they arc
broad, middle apical setfe rather elongated and somewhat thickened in their
proximal part. Anterior antenna' unusually short. 8-articulate. the first 4 joints
jradually diminishing in sixe, terminal part about half the length of the prox-
imal. Posterior antenna' with the outer ramus about the length of the terminal
joint of the inner, middle joint very small and imperfectly defined, without any
seta. M pair of legs rather strongly built, outer ramus much shorter than the
1-t joint of the inner, the middle joint being much the largest, with a small seta
at the end inside, last joint small, rounded, with 1 strong claw-like -pines and
a slender seta on the inner side; outer 2 joints of inner ramus very hort, the
last mie armed at the tip with 2 -tronv. claws of unequal length. Natatory legs
well developed, with the raiui rather broad and exhibiting the full number of
seta'. Last pair of legx very large, foliaceoiis. distal joint of unusual si/e. forming
a broadh oval lamella fringed with i> marginal seta) of rather unequal length:
inner expansion of proximal joint very broad, but scarcely extending to the middle
of the distal joint, marginal setae "> in number, the outermost one very small.
the :!rd much hmger than the others. (hisacs of moderate si/.e.

"l l''"iiinl lliN <umiii'T nitluT :iliimil:mll\ :it I'.'ii^iiinl. -nitli ,-.i;ist ..I' Nur\\;i\. in ;i
<|i-|itli >(' nln.ilt -JO f:it IHUIIS. inil'lds

Diosaccidas

Copepoda

Harpacticoida

P1.XCVII.

( B -

&

G.O.Sars autogr

Amphiascus imus (Brady)

Norsk lithgr. Officin

Diosaccidas

Copepoda

Harpacticoida

PLXCVIII.

/
. /

r I '
. ' ?

:^i.- Jjjf&k
,

\

G.O.Sars autogr.

Amphiascus Giesbrechti G.O.Sars.

Norsk lithgr. Officin

Diosaccidae

Copepoda

Harpacticoida.

P1.XC1X.

G.O.Sars autogr Norsk lithgr. Officin

Amphiascus propinqvus G.O.Sars.

Diosaccidae

Copepoda

Harpacticoida

P1.C.

G.O.Sars autogr.

Amphiascus lpngirostris,(Glaus)

Norsk lithgr Officin

Diosaccidas

Copepoda

Harpacticoida

Pl.CI

'"' ^'

A j\\ :/

il m I Ik f I / \\ \ A

| if

I

A \ \\

G.O.Sars autogr.

, . I , . /^i \ Norsk lithgr. OfHcin

Amphiascus iongirostris^Ulausj
(continued)

Diosaccidae

Copepoda

Harpacticoida

PLCII

/ - ! ^4

'

G.O.Sars autogr. Norsk lithgr. Officin

Amphiascus ten uirem is, (Brady)

Diosaccidae

Copepoda

Harpacticoida

P1.CIII

.:

.
-

,/ >*L i \-fi /.

*

r- /} U/l / :

/I' ^K v

N

i

3

: . -/- =*

^

At \ > v / ' - -f iainiiPt.-

%

GO.Sars autogr.

Amphiascus pan/us, G.O.Sars.

Norsk lithgr. Officin

Diosaccidas

uopepoaa

Harpacticoida

PLCNT

K3a ' ?}*#'

1 * /*3faat2iA .

im

G.O.Sars autogr Norsk lithgr. Officin

Amphiascus debilis ; (Giesbr.)

Diosaccidas

Copepoda

Harpacticoida

P1.CU

G.O.Sars autogr. Norsk iithgr Officin

Amphiascus pallidus, G.O.Sars

Diosaccidae

Gopepoda

Harpacticoida

P1.CVI.

,?

mi

^sii '(A '\v

411

G.O.Sars autogr. Norsk lithgr. Officin

Amphiascus abyssi 7 (Boeck)

Diosaccidae

Copepoda

Harpacticoida

PI.CVEL

Wft

G.O.Sars autogr Norsk lithgr. Officin

Arnphiascus hispidus,(Norm.)

Diosaccidae

Gopepoda

Harpactlcoida

PL cm

G.O.Sars autogr i i /KI \

Amphiascus nisp!dus,(norm.)
(continued)

Norsk lithgr. Officin

Diosaccidas

Copepoda

Harpacticoida

PI. CDC

G.O.Sars autogr Norsk lithgr. Ofncin

Amphiascus af finis G.O.Sars.

Diosaccidae

Copepoda

Harpacticoida

Pl.CX

G.O.Sars autogr. Norsk lithgr. Officin

Amphiascus intermedius,(Scott.)

Diosaccidae

Copepoda

Harpacticoida

.Pl.CXI

W 5 ?-

^

,/C

G.O.Sars autogr Norsk lithgr. Offlcin

Amphiascus typhlops, G.O.Sars

Diosaccidae

Copepoda

Harpacticoida

P1.CXU.

G.O.Sars autogr

Amphiascus attenu at us, G.O.Sara

Norsk lithgr. OfHcin

AN ACCOUNT

OF THE

CRUSTACEA

or

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS XV & XVI

DIOSACCID^] (concluded), CANTHOCAMPTID^E (part)

WITH 16 AUTOGRAPHIC PLATES

BERGEN

PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMEEMEYEE'S FOBLAG, CHRISTIANIA

1906

173

Male with the 2nd basal joint of 1st pair of legs armed inside with a
second small spine in addition to that occurring in the female. Inner ramus of
2nd pair of legs only slightly transformed, biarticulate, distal joint lamellar, with
a small dentiform projection at about the middle of the outer edge, and beyond
it a comparatively small spine, tip armed with a slightly curved spine and a
slender seta outside the latter, inner edge with 3 ciliated seta?. Last pair of legs
much smaller than in female, distal joint of insignificant size, and having only 4
partly spiniform setae; inner expansion of proximal joint very slight, with a slender-
seta and a very small spinule at the tip.

Colour not yet ascertained.

Length of adult female 0.74 mm.

Remarks. This new species is nearly related to A. similis Glaus, and
A. nasutus Boeck, and somewhat intermediate between these 2 species. It is
however easily distinguished from either of them by the much shorter and stouter
form of the body. In the structure of the anterior antennas it agrees with A.
similis, whereas that of the 1st pair of legs more resembles that in A. nasutus.
The last pair of legs are built upon the same type as in these 2 species, but are
of still larger size and pronouncedly foliaceous, whence the specific name here pro-
posed. In the male, the inner ramus of the 2nd pair of legs is very unlike that
in the 2 above-named species, and is far less conspicuously transformed.

Occurrence. Some few specimens of this form were found in a sample
taken last summer at Risor, on the south coast of Norway.

113. Amphiaseus nanus, G. 0. Sars, n. sp.

(PL CX1V, fig. 1).

Specific Characters. Female. Body comparatively short and stout, slightly
tapering behind, with the cephalic segment very large. Eostrum of moderate size
and usual form. Urosome much shorter than the anterior division. Caudal rami
very short, being about twice as broad as they are long, middle apical setse of
moderate length and slightly thickened at the base. Anterior antennae rather
elongated, 8-articulate, 4th joint somewhat longer than 3rd, terminal part consi-
derably exceeding half the length of the proximal one. Posterior antennae with
the outer ramus shorter than the terminal joint of the inner, middle joint very
small and without any seta. 1st pair of legs rather slender, outer ramus scarcely
exceeding half the length of the inner, middle joint without the seta on the
inner edge, last joint somewhat smaller and carrying on the tip 2 spines and 2

23 Crustacea.

174

geniculated setre; 1st joint of inner ramus very long and narrow, being more
ih an :i times as long as the other 2 combined, last joint only slightly longer
than the 2nd. and carrying at the tip a slender claw and a somewhat longer geni-
culated seta. Natatory legs with the rami rather narrow, the inner one consider-
ably shorter than the outer, seta? exhibiting a similar reduction in number to
that found in A. iliiij/is. Last pair of legs of moderate size, distal joint oval in
form and somewhat tapered towards the end, with 5 rather short marginal setse ;
inner expansion of proximal joint comparatively short, triangular in form, and
extending scarcely beyond the middle of the distal joint, marginal seta? 5 in
number. Ovisacs small and only slightly divergent, each containing, as a rule,
only 3 ova arranged in a single row.

Colour not yet ascertained.

Length of adult female 0.36 mm.

Remark*. This is one of the smallest of the species of the present genus,
and exhibits, in the structural details, some resemblance to A. ilrh/l/s (Glaus). It
is however easily distinguished from that species by its much shorter and stouter
body, and on a closer comparison, some well-marked differences are also found
in the structure of the several appendages.

Occurrence. Some few specimens of this dwarfed form, all of the female
sex, were found in the same sample in which A. jilit/l/njnis occurred.

114. Amphiaseus exiguus, G. 0. Sars, n. sp.

(PI. CXIV, liir. 2).

*l>t'c'ific Chni'iirlirs. Femali . Body very narrow, sublinear in form,
-carcely tapering at all behind. Cephalic segment of moderate size and narrowly
rounded in front; rostrum rather produced, lanceolate. Urosome almost as Inni:
ae the anterior division, segments coarsely spinulose at the hind edge ventrally
and laterally. Caudal rami comparatively small, about as long as they are broad,
apiral seta- of normal appearance. Eye not visible in the living animal. Anterior
antenna- comparatively short, 8-articulate, 2nd joint much the largest, fully as
long a> the 2 succeeding ones combined, terminal part not nearly half as long
aa the proximal part, and having the 3 first joints \ery small, and combined
scarcely longer than the last joint. Posterior antenna' about as in the preceding
species. 1st pair of legs with the outer ramus considerably exceeding half the
length of tin- inner, middle joint without any seta inside, last joint of about the same
si/.e. and armed with '2 spines and 2 geniculated seta-: inner ramus with the 1st

175

joint comparatively short, not attaining the length of the 2 remaining joints com-
bined, last joint linear and longer than the preceding one. Natatory legs moder-
ately slender, and having the number of setae somewhat reduced, inner ramus in
the 2 anterior pairs considerably longer than the outer, with the last joint very
narrow, and only provided inside with a single seta, 1st and last joints of the
outer ramus in these pairs quite smooth inside. Last pair of legs comparatively
small, distal joint oblong in form, scarcely contracted at the base, and carrying
6 marginal setse, the 2 apical ones hair-like; inner expansion of proximal joint
short, triangular, with 4 set&e, the 2 innermost very strong, spiniform. Ovisacs
small, each with only 3 ova arranged in a single row.

Male unknown.

Colour whitish.

Length of adult female 0.32 mm.

Remarks. This form is still smaller than the preceding one, and indeed
one of the smallest Harpacticoida known. It is moreover easily recognized by
its very narrow body, comparatively short anterior antennas, and by the structure
of the legs.

Occurrence. Only a solitary specimen, an ovigerous female, has hitherto
come under my notice. It was taken last summer at Farsund, south coast of
Norway, from a depth of about 30 fathoms, muddy sand.

115. Amphiaseus productus, G. 0. Sars, n. sp.

(PI. CXV).

Specific Characters. Female. Body exceedingly slender and elongated,
linear in form, being everywhere of uniform width. Rostrum much produced,
narrow lanceolate. Urosome nearly as long as the anterior division, segments
apparently without the usual circlets of spinules. Caudal rami very much pro-
duced, being considerably longer than the anal segment and about 4 times as
long as they are broad, apical setse normal. Eye^wholly absent. Anterior an-
tennse rather elongated, 8-articulate, with the first 2 joints of unusual size and
combined exceeding half the length of the antenna, 3rd and 4th joints of about
equal size, terminal part scarcely exceeding in length l / s of the proximal part.
Posterior antennae without the usual seta on the anterior edge of the proximal
part, outer ramus rather elongated, with the middle joint very small and without
any seta. 1st pair of legs slender, outer ramus about the length, of the 1st joint
of the inner, middle joint with a well-developed seta inside, last joint somewhat

176

longer, oblong oval in form, carrying 4 spines, and inside them a slender seta;
inner ramns with the last joint very slender and narrow, being more than 3 times
as long as the preceding joint, the two combined a little shorter than the 1st.
Natatory legs with the raini rather narrow, the inner one in the 2 anterior pairs
slightly exceeding in length the outer, in 4th pair considerably shorter, number
of seta less reduced than in the 2 preceding species. Last pair of legs of mod-
erate size and highly chitinized, distal joint narrow oblong in form, terminating
in a hook-like, outwards-curving projection, inside which 2 small hair-like bristles
are attached, outer edge irregularly indented and provided with only a single
seta, inner edge with 2 setse near the end, the distal one very slender and elong-
ated ; inner expansion of proximal joint narrow linguiform, extending beyond the
middle of the distal joint, and carrying 5 marginal setse, the 2 apical ones rather
small and somewhat unequal, the 2 innermost spiniform. Ovisacs comparatively
small, and containing a very limited number of ova.

M'llr somewhat smaller than female and exhibiting the usual sexual dif-
ferences. 2nd basal joint of 1st pair of legs with 2 obtuse projections inside in
addition to the spine. Inner ramus of 2nd pair of legs transformed in the usual
manner. Last pair of legs smaller than in female, but with the distal joint of a
very similar shape, inner expansion of proximal joint less developed, and provided
with only 2 unequal spines bifid at the tip.

Colour whitish.

Length of adult female 1.14 mm.

Remarlcs, This is a very distinct and easily recognizable species. In the
total absence of eye, and the unusually produced caudal rami, it somewhat recalls
the above-described A. typhlops. It is however of still more slender form of body,
and moreover differs in the much more elongated anterior antenna?, as also in the
peculiar structure of the last pair of legs in both sexes.

Oci-iin-t are. Seyeral specimens of this remarkable form were taken last
summer at Farsund, south coast of Norway, from a depth of from 30 50 fathoms,
muddy sand.

116. Amphiascus tenellus, G. 0. Sars, n. sp.

(PI. CXVI).

S/ii-ci/ic Chiifiii-f, fx. l'\,niilc. Body rather slender, though not to such a
<lf_'ree as in the preceding species, being slightly attenuated behind. Integuments
very thin and pellucid. I\us| nun narrow, lanc.-.ilatr. I'msniue shorter than the

177

anterior division, and having the segments finely spinulose at the hind edge ven-
trally and laterally. Caudal rami short, being considerably broader than they
are long, apical setse normal. Eye inconspicuous. Anterior antennae very slender
and attenuated, 8-articulate, 2nd joint much the largest, 4th joint very narrow
and twice as long as 3rd, terminal part not quite attaining half the length of the
proximal one. Posterior antennae with the outer ramus about as long as the
terminal joint of the inner, middle joint well defined and setiferous. 1st pair of
legs with the outer ramus shorter than the 1st joint of the inner, middle joint
with a well-developed seta inside, last joint scarcely larger, and armed with 3
spines and 2 geniculated setse; inner ramus with the 1st joint very narrow, last
joint more than twice as long as the preceding one, the two together about half the
length of the 1st. Natatory legs with the rami nearly equal-sized, and having the
normal number of setse. Last pair of legs very delicate, distal joint regularly
oval in form, with the tip obtusely blunted, marginal setaB rather small and 6 in
number; inner expansion of proximal joint triangular, extending considerably
beyond the middle of the distal joint, and produced at the end outside to a small
tooth-like projection, inside which a row of 5 setse occur. Ovisacs narrow oblong,
with a very limited number of ova.

Male having the 2nd basal joint of 1st pair of legs armed inside with 2
closely-set spines, in front of which is a small knob-like prominence. Inner ramus
of 2nd pair of legs transformed in the usual manner. Last pair of legs very
small, with the distal joint short and broad, and the inner expansion of the prox-
imal joint very slight, tipped with 3 unequal spines.

Colour whitish.

Length of adult female 0.54 mm.

Remarks. This form is chiefly characterised by the very thin and pel-
lucid integuments, the unusually slender anterior antennae, and the structure of
the 1st and last pairs of legs. No eye could be detected in the living animal.

Occurrence. Some few specimens of this handsome species were taken last
summer in the same locality in which A. productus occurred.

117. Amphiascus linearis, G. 0. Sars, n. sp.

(PI. CXVII).

Specific Characters. Female. Body very slender and elongated, linear
in form, being of equal width almost throughout. Rostrum less produced than
in most other species, narrow lanceolate in shape. Urosome almost attaining the

178

length of the anterior division. 'uncial rami very small, somewhat narrowed
distally, apical setae normal. Kye small, but distinct. Anterior antennae rather
slender and attenuated. 8-articulate, 2nd joint the largest, 4th joint scarcely twice
as long as 3rd, terminal part about half the length of the proximal one. Posterior
antennae with the outer ramus very small, being much shorter than the last joint
of the inner, middle joint without any seta. 1st pair of legs with the outer ramus
about as long as the 1st joint of the inner, middle joint without any seta inside,
lat joint considerably longer, and armed with '2 spines and 2 geniculated setae;
inner ramus with the last joint more than twice as long as the preceding one,
both together somewhat exceeding half the length of the 1st. Natatory legs with
the rami almost equal-sized, number of setae much reduced. Last pair of legs
with the distal joint oblong, narrowly exserted at the tip, and carrying 5 some-
what unequal marginal setce, that issuing from the tip being the longest; inner
'\pansion of proximal joint narrow linguiform, and extending somewhat beyond the
middle of the distal joint, marginal setae 5 in number, the 2 innermost compara-
tively short and spiniform. Ovisacs rather narrow and only slightly divergent.

Mnl, with the 2nd basal joint of 1st pair of legs produced inside to 2
coarse diverging projections. Inner ramus of 2nd pair of legs large, and of a
-tructure similar to that in the male of A. ili'liilix. the distal joint being exserted
at the end in a long mucroniform projection. Last pair of legs resembling in
structure that in the male of .1. tc)i<'l/*, but having the distal joint more ex-
serted at the tip.

Colour whitish.

Length of adult female 0.63 mm.

Ji'rmfirk*;. In its external appearance this species somewhat resembles
A. imus (Brady), exhibiting a similar very slender form of body. It is however
f much inferior size, and moreover differs in its less prominent rostrum and in
the structure of the natatory legs, which latter are built on the very same type
as in .1. ilrliilis.

Orrtim-ttrc.Some specimens of this form were found last summer together
with the 2 preceding species at Farsund, south coast of Norway.

11*. Amphiaseus sinuatus, (-J. <). Sars. u. sp.

(I'l. CXVIII).

N///Y-///V Characters. Female. Body moderately slender, resembling in

that 1. 1 .1. /oy/,///W/-/>-. though perhaps MMIICU hat less robust. Cephalic

179

segment comparatively large, being fully as long as the 4 succeeding segments
combined, epimeral parts exhibiting in front of the middle a very conspicuous
sinus. Rostrum very prominent, lanceolate. Urosome almost as long as the
anterior division, and slightly attenuated behind, anal segment scarcely shorter
than the preceding segment. Caudal rarni short, quadrangular, broader than they
are long, apical setse only slightly thickened at the base. Eye well developed.
Anterior antennae rather slender, 8-articulate, 4th joint almost twice as long as
3rd, terminal part half the length of the proximal part. Posterior antennae with
the outer ramus about as long as the terminal joint of the inner, and distinctly
3-articulate, middle joint well defined and setiferous. 1st pair of legs compara-
tively slender, outer ramus considerably shorter than the 1st joint of the inner,
middle joint with a well-developed seta inside, last joint of about the same length,
and armed with 3 spines and 2 geniculated setse; inner ramus with the 1st joint
very slender, more than twice as long as the other 2 combined, last joint about
twice as long as the preceding one. Natatory legs with the inner ramus in the
2 anterior pairs scarcely shorter than the outer, last joint of outer ramus in these
pairs with only a single seta inside. Last pair of legs with the distal joint rather
large, broadly oval in form, and provided with 6 marginal setse, the 2 apical ones
very thin, hair-like; inner expansion of proximal joint narrow triangular, extend-
ing beyond the middle of the distal joint, and carrying 5 spiniform marginal setse
of nearly equal size. Ovisacs of moderate size.

Male with the inner ramus of 2nd pair of legs transformed in the usual
manner. Last pair of legs much smaller than in female, with the distal joint of
far inferior size, and only provided with 5 setse ; inner expansion of proximal joint
conically produced, and carrying 2 subequal setse on the tip.

Colour not yet ascertained.

Length of adult female 0.80 mm.

Remarks. This form, both in size and general appearance, bears a per-
plexing resemblance to A. longirostris Glaus. It may, however, be at once dis-
tinguished from this form, in its lateral aspect, by the shallower cephalic segment,
and still more by the very conspicuous sinus which the epimeral parts form in front
of the middle, a character which has given rise to the specific name here proposed.
Moreover the structure of the outer ramus of the posterior antennae, and that of
the legs, is somewhat different. Finally, the innermost but one of the caudal setse
does not exhibit any trace of the peculiar bulging at the base found in A. lon-
girostris.

Occurrence. ^l^ species was also found last summer occasionally in the
same locality in which the 3 preceding new species occurred.

Ksn

Gen. 40. Stenhelia, Boeck, 1864 (not Brady).

Syii: Delaralia, Brady.
Beatrici'lln. Scott,

<n in ni- Cliii,-iirt, /:<. Body more or less pyril'orm in shape, with the ce-
phalic segment very large and tumid. Rostrum quite immobile, though distinctly
detined at the base, forming a broad triangular plate slightly indented on each
side of the tip. and provided ventrally with a projecting carina. Epimeral plates
"!' the 3 succeeding segments small, rounded. Urosome comparatively short and
gradually tapered behind. Caudal rami more or less produced, with the normal
number of setae. Eye well developed. Anterior antennae comparatively short and
densely setiferous, 8-articulate, with the joints of the proximal part very sharply
defined and gradually diminishing in size; those of male transformed in the usual
manner. Posterior antenna? with the terminal joint rather large, apical spines
scarcely geniculated, outer ramus well developed, inarticulate. Mandibles very
strong, palp large, with the basal part much produced, inner ramus bent abruptly
backwards, and carrying on the tip a very strong, elongated falciform seta,
accompanied by one or two smaller ones, outer ramus very delicate, forming a
thin setiferous lamella. Maxillae and anterior maxillipeds of normal structure.
Posterior maxillipeds very small, in some cases not prehensile. 1st pair of legs
of exactly the same structure in the two sexes, outer ramus inarticulate, inner in
some cases distinctly 3-articulate and prehensile, in other cases composed of only
2 joints. Natatory legs strongly built, with both rami triarticulate and nearly
equal in size, except in the 4th pair ; inner ramus of 2nd pair in male transformed.
Last pair of legs with the distal joint very mobile, forming a more or less broad
lamella generally extended laterally ; inner expansion of proximal joint short and
broad; those in male much smaller than in female, in some cases quite rudimen-
tary. Ovisacs more or less divergent, sub-lateral.

It'i iinirl.-s. This genus was established in the year 1864 by Boeck, to
comprise 2 Norwegian species, viz., S. i/i/>f>n and S. lon<iirtntiliitti. Brady wrongly
referred to this genus 2 species belonging to the genus Amphiascus, as here de-
fined, whereas 3 other species, which undoubtedly belong to Boeck's genus, were
rel'rrred by him to the new genus Dt'lnruHn. and all subsequent British authors have
followed Brady in this respect. Dr. Giesbrecht also described a species of Am-
iisrn* as a tfi'-iilt, Int. though he seems to have been aware of the disagreement
Boeck's definition of the genus with that given by Brady. The genus Beatn-
recently established by Th. Scott is also unquestionably identical with Boeck's
genus, lifiim indeed founded upon the type of the latter genus. The most pro-

181

minent character of the present genus is the very peculiar structure of the man-
clibular palp, to which also Boeck has called attention. Moreover the feeble
development of the posterior maxillipeds, and the peculiar shape of the last pair
of legs, are characteristic features of this genus. Finally the rostrum is quite
immobile, and in form also differs from that in the 2 preceding genera. We
know at present of 8 species belonging to this genus, 7 of which occur off the
Norwegian coast, and will be described below.

119. Stenhelia gibba, Boeck.

(PL CXIX & CXX, fig. 1).

Stenhelia gibba, Boeck, Oversigt over de ved Norges Kyster iagttagne Copepoder. Chr. Vid. Selsk.

Forliandlinger f. 1864, p. 271.

Syn: Delavalia mimica, Scott.
Beatricella mimica, Scott.

Specific Characters, Female. Body rather robust, pyriform, with the ce-
phalic segment very large and tumid, being gibbously vaulted above. Rostrum
triangular, about as long as it is broad at the base, tip obtusely blunted and
defined on each side by a distinct ledge carrying a small hair. Urosome much
shorter than the anterior division, and rapidly tapered distally, genital segment
scarcely constricted in the middle, though much broader in front than behind.
Caudal rami scarcely divergent, being about twice as long as they are broad, and
transversely truncated at the tip, apical setae rather slender. Anterior antennse
much shorter than the cephalic segment, and somewhat curved, 1st joint much the
largest, being about as long as the 2 succeeding joints combined, terminal part
somewhat exceeding half the length of the proximal part. Posterior antennse with
the outer ramus about the length of the last joint of the inner, and carrying 6
setse, 3 apical and 3 lateral, middle joint short, the other 2 of about equal size.
Posterior maxillipeds small, with the hand somewhat lamellar, dactylus short but
distinctly biarticulate. 1st pair of legs with the outer ramus shorter than the
1st joint of the inner, middle joint without any seta inside, last joint somewhat
smaller and obliquely truncated at the end, carrying 3 slender spines and a still
more slender seta inside them; inner ramus distinctly triarticulate and sub-pre-
hensile, 1st joint very large, being about 3 times as long as the other 2 combined,
the latter subequal in size and bent at an angle to the 1st, last joint armed on
the tip with a slender claw-like spine, an elongated seta, and a small hair-like
bristle. Inner ramus of the 2 succeeding pairs about the length of the outer,
that of 4th pair much shorter, not extending beyond the 2nd joint of the outer.

24 Crustacea.

Last pair of legs with the distal joint oval in form and carrying 6 marginal setae,
2 on the outer edge, 2 on the inner, and 2 on the somewhat exserted tip, proxi-
mal seta >f outer edge rather coarse, spiniform ; inner expansion of proximal joint
rather broad, but only slightly prominent, and armed with 5 rather short and
somewhat unequal marginal spines, the innermost but one much thicker than the
others and provided on each side of the short triangular point with a single small
hair. Ovisacs rather large and widely divergent.

Mali somewhat smaller than female, and easily recognizable by the pre-
hensile character of the anterior antennae. Inner ramus of 2nd pair of legs
Inarticulate, distal joint rather dilated at the base and exserted at the em I
in a slender setiform appendage having in the middle a somewhat oblique row
of very delicate cilia, inner edge provided with 3 seise, the distal one much elon-
gated. Last pair of legs with the distal joint very small and quite immobile,
marginal setae only 4 in number and spiniform; inner expansion of proximal
joint very slight, and armed with a single thick spine of the same appearance as
the innermost but one in the female, and accompanied outside by an extremely
minute spimile. Genital lobes with 2 hair-like bristles, inside which is an out-
ward-curvinu; spine.

Body in both sexes of a more or less distinct reddish colour.

Length of adult female 0.62 mm.

Remarks. This is the form at first recorded by Boeck as the type of
his genus Stcnhel'm. The Dc/nral'm mi mica of Scot is unquestionably identical
with Boeck's species. The said author has recently established a new genus,
i:it,iceUa, for this species, on account of the prehensile character of the inner
ramus of the 1st pair of legs; but as the present form in all other respects agrees
perfectly with the other species referred by that author to the genus Dcln-
nilin of Brady, I cannot find any reasonable support for such a generic distinction.
It will also be shown below, that in one of the species, described by Th. Scott
/hlttniliu n nn/lu, the inner ramus of the 1st pair of legs, though distinctly
inarticulate, has wholly lost its prehensility, as in most other species of the pre-
sent genus.

OccurrriifC. This form is rather common in the upper part of the Chris-
tiania Fjord in depth- ranging from 6 to "2" fathoms, muddy bottom. It also
occurs along the whole south and west coasts of Norway, as also in the Trond-
Fjord (Levanger).

Scottish coast (Scott).

183

120. Stenhelia proxima, G. 0. Sars, n. sp.
(PI. cxx, fig. a).

Specific Characters. female. Very like the preceding species, but of
somewhat smaller size and more robust form of body. Rostrum resembling in
shape that in S. yibba, though having the tip slightly emarginated. Caudal rami
somewhat more divergent, otherwise of a very similar appearance. Antennse and
oral parts almost exactly as in 8. giblm. 1st pair of legs with the outer ramus
longer than the 1st joint of the inner, last joint somewhat longer than the middle
one; inner ramus, as in 8. yibba, triarticulate and prehensile, the 2 outer joints
short and bent at an angle to the 1st, which is more than twice as long as those
joints combined. Natatory legs of much the same structure as in the typical
species, inner ramus, however, a little shorter. Last pair of legs with the distal
joint broader, sub-spatulate in form, innermost seta considerably longer than the
other, inner expansion of proximal joint less broad than in 8. yibba, all the mar-
ginal setae much longer than in that species, the innermost but one stronger than
the others, and terminating in a slender ciliated lash. Ovisacs comparatively
smaller and less divergent, with a more limited number of ova.

Male resembling that of 8. yibba. Inner ramus of 2nd pair of legs
transformed in a very similar manner, terminal appendage however comparatively
shorter, and having in the middle a whorl of a few rather coarse denticles. Last
pair of legs resembling those in the male of 8. yibba, the 2 spines attached to
the proximal joint inside, however, more elongated, the larger one terminating in
a slender lash. Genital lobes, as in the male of 8. yibba, provided with 2 hair-
like bristles, and within them with a somewhat hooked spine.

t

Colour pale reddish.

Length of adult female 0.49 mm.

Remarks. This form is closely allied to S. yibba, and may easily be
confounded with it. It is however of far inferior size, and moreover differs some-
what in the structure of the 1st and last pairs of legs.

Occurrence. I have met with this form not [infrequently off the south
coast of Norway, at Flekkero and Farsund, in depths ranging from 10 to 30 fathoms.

1 -!

121. Stenhelia aemula < Scott).

i n. i \\i

a,, niln. s. . A'l'liiioiix t<> tip- Fnuna <>t' th- Firth of Forth: Kli-vciith It-port of the
FMi.-ry IJoanl lor Scotland, p. i!O.J. PI. IV. figs. 3647.

Sfxci/ic Characters. Female. Body of the usual short pyriform shape,
being pi-rhaps still more rohust ilian in the '2 preceding species. Rostrum some-
what more attenuated, with the tip transvei'M'lv truncated. Caudal mini a little
lunger than the anal segment, and slightly tapered distally. Antemue and oral
parts scarcely different from those in the typical species. 1st pair of legs with
the outer ramus about as in that species, the last joint being somewhat shorter
than the middle one, which is without any seta inside; inner ramus longer than
the outer, and distinctly 3-articulate, 1st joint, however, much shorter than in the
2 preceding species, being scarcely longer than the other 2 combined, the latter
not bent upon the former, and of about equal size. Natatory legs very strongly
built, with the 1st joint of the inner ramus considerably dilated, and in 4th pair
carrying inside an unusually strong deflexed seta. Last pair of legs with the
distal joint spatulate in form, the tip being obtusely blunted, marginal seta3 rather
slender, none of them spiniform; inner expansion of proximal joint very slight,
and carrying 4 slender ciliated setaj, the outermost shorter than the other 3.
Ovisacs not very large, and containing a limited number of ova.

Colour not yet ascertained.

Length of adult female 0.50 nun.

It'i muflct. The above-described form is unquestionably that recorded by
Th. Scott as J)<'li<r//ii <r,,i<il<t. though somewhat interior in sixe. It is chiellv
characterised by the structure of the inner ramus of the 1st pair of legs, which.
though distinctly triarticulate, as in the 2 preceding species, is scarcely at all
prehensile, a character which gives it a place between those two and the suc-
ceeding species. Th. Scott has also examined the male of this species, and gives
a figure of the 2nd pair of legs, the inner ramus of which appears to be trans-
tunned in much the same manner as in the '2 preceding species.

Occurrence. -Only some few specimens of this form, all of the female
-'x, have hitherto come under my notice. The\ were taken last summer off the
south coast of Norway, at Klekkeru and Karsund.

I>i*ti-il>iittoH. Scottish coast (Scott).

185

122. Stenhelia palustris (Brady).

(PI. CXXII).
Ddavalia palustris, Brady, Monogr. Brit, Copepoda, Vol. II, p. 43, PI. 4, figs. 1 8.

Specific Characters. Female. Body, as in the 3 preceding species gra-
dually tapered behind, but somewhat less robust, with the segments more sharply
marked of from each other. Rostrum with the apical part less sharply defined
and somewhat retuse at the tip. Urosome much shorter than the anterior division,
anal segment coarsely spinulose at the hind edge ventrally and laterally. Caudal
rami exceeding in length the anal segment, and somewhat constricted at the base,
apical setae comparatively shorter than in the other species and more divergent.
Anterior antennae with the last 3 joints imperfectly defined, otherwise of the usual
structure. Posterior antennas, mandibles, maxillae and anterior maxillipeds scarcely
different from those parts in the 3 preceding species. Posterior maxillipeds
very delicate and not at all prehensile, the propodal joint being lanieHiform, and
the dactylus replaced by a simple seta. 1st pair of legs with the outer ramus
coarsely spinulose outside, middle joint with a well-developed seta inside, last
joint a little longer and obliquely truncated at the tip, carrying 2 strong spines
and 2 unequal setae, neither of which is geniculated ; inner ramus scarcely as long
as the outer, and consisting of only 2 joints, the 1st provided inside, as in the
other species, with a strong plumose seta, last joint longer and narrower than
the 1st, and without any seta inside, outer edge clothed with 2 oblique rows of
spinules, tip produced outside to a short dentiform point, inside which a slender
denticulated spine and a somewhat shorter seta are attached. Natatory legs
strongly built and of normal structure. Last pair of legs with the distal joint
almost quadrangular in shape, tip obtusely rounded, and carrying 6 not much
elongated setae, proximal joint not expanded inside, and confluent with that of
the other side, the posterior edge carrying 2 unequal setae at a short distance
from the insertion of the distal joint, and farther inwards an extremely small
hooked spinule and a short bristle. Ovisacs very large and divergent.

Male with the inner ramus of 2nd pair of legs biarticulate, distal joint
oblong oval in form, scarcely tapering behind, and terminating in a short denti-
form point, outside which quite a short curved seta is attached, coarsely ciliated
in the middle, inner edge carrying in front of the middle 2 unequal setae and near
the end a very coarse deflexed spine, bifid at the tip, and having inside a few
spinules. Last pair of legs quite rudimentary, being reduced to a narrow trans-
verse plate carrying on each side a strong spine and 3 simple setae. Genital
lobes somewhat unequal, each with 3 hair-like bristles.

186

Colour whitish, with a slight yellowish tinge.

Length of adult female 0.80 mm.

Remarks. This form was recorded by Prof. P>ra<ly as early as the year
1868, and was subsequently described and figured by the same author in his well-
known Monograph as the type of the genus Drlm-al'm. Though differing in some
points from the 3 preceding species, it ought, in my opinion, to be considered as
congeneric with them, the differences being of only specific value. It is much
the largest of the Norwegian species.

Occurrence. I have only met with this form in a single locality not far
from Ohristiania. It occurred there not (infrequently at a depth of about 3 fathoms.
muddy bottom.

Distribution. "British Isles (Brady).

123. Stenhelia reflexa (Brady).

(PI. ('XXII I).

,T/li:ni. lirailv. Monogr. British Copepoda, Vol. II, p. 45, PI. LI, figs. 18, 11, 13

(not figs. 9, 10, 12, 14).

ifir Chiinirtrr*. Female. Body short and robust, with the anterior
division considerably dilated, the posterior much narrower and slightly tapered
behind. Rostrum rather prominent and rapidly attenuated, with the apical part
narrowly lingoiform in shape. Urosome not much shorter than the anterior divi-
sion, genital segment conspicuously dilated in front, anal segment larger than the
preceding segment. Caudal rami about the length of the anal segment, and slightly
tapered distally, apical setse slender, the outermost one of unusual length. Anterior
antennae somewhat more slender than in the preceding species, otherwise of the
ii-ual structure, all the joints well defined. Posterior antenna: with the outer
ramus much shorter than the last joint of the inner, terminal joint not attaining
the length of the 1st. Mandibular palp with the basal part somewhat dilated in
the middle, inner ramus very narrow and abruptly retlexed. carrying on the tip
only '2. setse, the one, as usual, much elongated and falciform. Maxilla 1 and
maxillipeds about as in <S. i/i/i/m. 1st pair of legs with the outer ramus about
the length of the inner, middle joint with a well-developed seta inside, last joint of
about the same si/e. and carrying 3 slender spines and 2 somo\\hat unequal setse;
inner ramus, as in N. /mltitlri*. consisting of only 2 joints, the last one equal in
length to the 1st, and currying near the base inside a ciliated seta, tip armed
with a slender spine and 2 somewhat longer sctte. Natatory legs rather strongly

187

built, with some of the setae spiniform. Last pair of legs, with the distal joint
spatulate in form, being conspicuously constricted at the base and broadly blunted
at the tip, which carries 5 setae, 2 of which are very small, hair-like; inner ex-
pansion of proximal joint broadly rounded, and provided with 4 slender, nearly
equal ciliated seta?. Ovisacs of moderate size. Spermatophore, attached to the
genital opening, unusually large, pyriform.

Male, as usual, smaller than female, but having the caudal rami of ex-
actly the same shape. Inner ramus of 2nd pair of legs rather slender, biarti-
culate, distal joint gradually tapered and exserted at the end in a comparatively
short denticulated spiniform projection, outside which is a still shorter outward-
curving spine, inner edge carrying 4 somewhat unequal setae. Last pair of legs
with the distal joint very small and imperfectly defined at the base, proximal
joint forming inside, at some distance from the insertion of the distal joint, a
short conical lobe tipped with a slender seta.

Colour pale yellowish.

Length of adult female 0.52 mm.

Remarks. It seems to me beyond doubt, that Prof. Brady under the
name of Delavalia reflexa has confounded two distinct species, some of the figures
given, especially those representing the 1st pair of legs and the male caudal rarni,
being unquestionably referable to a very different form, viz., Stenhelia longicau-
data Boeck, to be described farther on. The name reflexa proposed by Prof.
Brady for the present form is somewhat inappropriate, referring as it does to a
pecularity common to all the species of this genus, as also to some other Cope-
poda, viz., that in preserved specimens the posterior part of the body is often
found abruptly bent dorsally upon the anterior. The present species is especially
characterised by the form of the rostrum and the structure of the 1st and last
pairs of legs. In the living state it is moreover easily recognized by the pale
yellow colour of the body, for which reason, before recognizing its identity with
Brady's species, I had noted it under the provisional name 8. flavida.

Occurrence. I have met with this species in 3 different localities of the
Norwegian coast, viz., in the upper part of the Christiania Fjord, at Farsund,
south coast of Norway, and at Bejan, entrance to the Trondhjem Fjord. In all
3 localities it occurred very sparingly at a depth of about 20 fathoms.

Distribution. British Isles (Brady).

Stenhelia Giesbreehti (Scott).

(PI. CX XIV. tig. 1).

<< Ml, Tli. Scott, On SOUP- in-w ami ran' ( '. .]H'|M "la iVmn tlie Clvd.-: Annals of

Scottish N.it. Hist. IS'.Jfi, p. Ui':>. I'l. IV. figs. 1 10.

ific Characters. Female. Body of the usual short pyriform shape.
though scarcely as robust as in the preceding species, the anterior division being
less dilated in front. Rostrum broadly triangular, with the apical part well de-
fined and slightly bitid at the tip. Urosome considerably shorter than the anterior
division and somewhat attenuated distally, genital segment conspicuously dilated
at the base, anal segment shorter than the preceding one. Caudal rami not much
produced, being scarcely twice as long as they are broad and rather approximate,
innermost but one of the apical setse slender and elongated, and conspicuously
ciliated in the middle, the adjacent seta on the outer side very peculiarly trans-
formed, being remarkably dilated throughout the greater part of its length, almost
sausage-shaped, and terminating in a very thin and slender hair-like lash, the
dilated part coarsely ciliated on both edges distally. Anterior antennae compara-
tively short and of the usual structure. Posterior antenna.- with the outer ramus
very slender, exceeding in length the last joint of the inner. Oral parts of the
usual structure. 1st pair of legs with the outer ramus about the length of the
inner, middle joint provided inside with a distinct, though rather small seta, last
joint a little longer and armed with 2 slender spines and 2 still longer setse;
inner ramus biarticulate, distal joint longer and narrower than the proximal one,
and provided at the tip with a slender spine and a ciliated seta, inside with 2
similar seta. Natatory legs moderately strong and of the usual structure. Last
pair of legs with the distal joint oblong quadrangular in form, carrying on the
somewhat obliquely truncated end 5 setrc, the middle one being very small, hair-like;
inner expansion of proximal joint rather slight and subangular inside, carrying 4
slender ciliated seta', the 2 outermost ones smaller than the other 2, and arranged
'lose together. Ovisacs comparatively small and but slightly divergent, containing
a \er\ limited number of ova.

Ml<' unknoun.

< '"lour whitish.

Length of adult female 0.44 mm.

/.'< murk*. This is a very small form, and at once recogni/able from any
of the other species of the genus by the peculiar transformation of the outer
one of the 2 middle caudal seta 1 , as also by the rumparat i\ el\ -mall and appres-
I <>\i.-acs.

189

Occurrence. Several specimens of this form, all of the female sex, were
found last summer at Farsund, south coast of Norway, at a depth of from
20 30 fathoms, muddy sand.

Distribution. Scottish coast (Scott).

125. Stenhelia Normani (Scott).

(PL CXXIV, fig. 2).

Delavalia Normani, Th. Scott, Notes on British Copepoda, Ann. Mag. Nat. Hist. ser. 7,

Vol. XVI, p. 569.

Specific Characters. Female. Very like the preceding species both in
size and general appearance. Genital segment however more abruptly constricted
in the middle, and the remaining part of the urosome narrower and scarcely at
all attenuated behind. Caudal rami more divergent and having the setse of quite
normal appearance. Anterior antennse comparatively shorter and stouter than in
S. Giesbrechti. Posterior antennse with the outer ramus very slender, consider-
ably exceeding in length the last joint of the inner. 1st pair of legs of almost
exactly the same structure as in S. Giesbrechti. Natatory legs likewise very similar.
Last pair of legs with the distal joint comparatively shorter and broader, and
having the setse more elongated; inner expansion of proximal joint carrying 4
slender setse arranged in a manner similar to that in S. Giesbrechti. Ovisacs

comparatively larger and more divergent.

Male with the inner ramus of 2nd pair of legs somewhat unlike that in
the other species, distal joint rather large and slightly dilated in the middle,
carrying on the tip 2 unequal straight spines, outer edge with a small dentiform
projection beyond the middle, inner edge provided with 2 setse in the middle and
near the end with an elongated deflexed spine, coarsely denticulated in its outer
part. Last pair of legs with the distal joint very small and imperfectly defined
at the base, carrying 3 spines, the outermost of which is rather strong; proximal
joint scarcely at all expanded inside, but provided with 2 unequal setse in its
innermost part.

Colour whitish.

Length of adult female 0.46 mm.

Remarks. This form was at first regarded by Th. Scott as only a variety
of 8. Giesbrechti. Recently he has however vindicated its specific distinctness,
and has proposed for it the above name. It is indeed closely allied to the said
species, but on a closer comparison some differences are found to exist which

25 Crustacea.

HIM

seem to be fairly constant, the most conspicuous of them being the structure of
the caudal set* and the form of the ovisacs.

Occurrence. I have found this form not (infrequently oft' the south coast
of Norway, at liisor and Lillesand, at moderate depths among alga 1 .

/>'i*ti-il>ntiit. Scottish coast (Scott).

126. Stenhelia longicaudata, Boerk.

(PI. CXXV, fig. 1).

31 -ili<:l m lii,ii/iciiiiilii/ii. Boeck, Nye Slsegter og Arter af Saltvandscopepoder. Chr. Vid. Selsk.

l-Wh. 1872, p. 49.

Sj'n: Delaralia rcflt\ca, Brady (part).

Scott.

i^. Female. Body rather short, and robust resembling
somewhat that of S. rcfte./'a. Rostrum rather prominent and attenuated distally,
apical part very minute and transversely truncated at the end. Genital segment
conspicuously dilated in its proximal half, remaining part of urosome only slightly
attenuated, anal segment about the length of the preceding one. Caudal rami
very narrow and elongated, exceeding in length the 2 preceding segments com-
bined, and widely apart, apical setae of moderate length and normal appearance.
Anterior antennae of the usual structure. Posterior antenna 1 with the outer ramus
shorter than the last joint of the inner. Oral parts of quite normal structure.
1st pair of legs with the outer ramus considerably longer than the inner, middle
joint provided inside with a short seta, last joint rather shorter and armed with
2 slender spines and 2 seta 1 ; inner ramus Inarticulate, distal joint quite short.
scarcely half as long as the proximal one, and provided inside 1 with a small seta,
tip carrying 3 seta;, the middle one being much the largest and remarkably
thickened at the hasc, terminating in a very delicate and finely ciliated lash.
Natatory legs of the usual structure. Last pair of legs with the distal joint pro-
nouncedly spatnlate in form, and provided with 6 setae, 2 of which issue from
the outer edge. innermost seta very slender and elongated; inner expansion of
proximal joint \er\ slight and exhibiting near the insertion of the distal joint a
sin. .11. but rather conspicuous incision, marginal seta 1 slender and 4 in number,
the outermost issuing close to the next, and being smaller than the others. Ovisacs
of model-ate' size and rather divergent.

M'llr with the inner ramus of 2nd pair of legs rather peculiar in shape,
the proximal joint being strongly dilated and without an\ seta inside, distal joint

191

exhibiting inside in the middle a deep excavation and carrying on the tip a single
slender spine, inner edge below the excavation provided with a similar spine, and
in front of it with a simple seta. Inner ramus of 3rd pair of legs also somewhat
transformed, though consisting of 3 well-defined joints, the last of which, however,
is considerably larger than in female, and provided with an additional seta inside.
Last pair of legs with the distal joint well defined, but very small, not dilated
towards the end and only provided with 4 small seta3; inner expansion of prox-
imal joint very slight and carrying 2 subequal setse.

Colour more or less distinctly reddish.

Length of adult female 0.48 mm.

Remarks. This form has been very imperfectly characterised by Boeck,
and was therefore not recognised by Mr. Scott, who described it as a new species
under the naina of Ddavalia minutissima. Some of the figures given by Prof.
Brady of his species Delavalia reflexa (for instance figs. 9 and 14) undoubtedly
refer to the present form. The most prominent feature of this species is unques-
tionably the very narrow and elongated caudal rami, a character which indeed has
given rise to the specific name longicawlata proposed by Boeck. In the structure
of the 1st pair of legs it somewhat resembles Delavalia rolmsta of Brady, a spe-
cies which also may be referred to the Norwegian fauna, as it is recorded by
Th. Scott from Finmark.

Occurrence. I have met with this form occasionally in the upper part of
the Christiania Fjord, as also at Flekkero, south coast of Norway, in moderate
depths among algae.

Distribution. British Isles (Brady, Scott).

Gen. 4L. StenheliOpSiS, G. O. Sars, n.

Generic Characters. General form of the body somewhat resembling that
in Sterihelia,, being rather short and stout. Rostrum immobile, forming a thin
linguiform plate, without any ventral carina. Urosome much narrower than the
anterior division. Caudal rami long and narrow, divergent. Anterior antennae
short and much curved, with the number of articulations reduced. Posterior an-
tenna3 rather strongly built, but with the apical setce comparatively small, outer
ramus of moderate size, Inarticulate. Mandibles with the palp of quite normal
appearance. Maxillae and anterior maxillipeds likewise of usual structure. Poste-

192

rior maxillipeds terminating in a well-developed prehensile hand. 1st pair of legs
with the inner ratnus Inarticulate and not prehensile. Natatory legs not very
different in structure 1'rom the 1st pair, nil having the inner minus hiarticulate
and much coarser than the outer. Last pair of legs very small, distal joint quite
rudimentary and not defined at the hast.-: proximal joint only slightly expanded
inside. Ovisacs small, containing a very limited numher of ova. .!/"/ unknown.
RemarJcs.ThiB new genus is somewhat allied to Stenhelia, but differs
very materially in several of the anatomical characters. It contains as yet only a
single species, to be described below.

127. Stenheliopsis divaricata, G. 0. Sars, n. sp.

(PI. CXXV, fig. 2).

/ic ('hrt-tc,rs. Female. Body short and stout, with the anterior
division considerably dilated, the posterior rather narrower. Cephalic segment
very large and vaulted above. Rostrum rather prominent, forming a very thin
linguiform plate, evenly rounded at the tip. Urosome almost as long as the an-
terior division, and only slightly attenuated behind, genital segment scarcely at
all dilated in front. Caiidal rami exceedingly slender and elongated, attaining
about half the length of the urosome, and curving outwards, apical seta3 extended
laterally, the innermost but one rather coarse, with the distal part closely annul-
ated and clothed with short cilia; outer edge of the rami carrying a short seta
at some distance from the tip. Eye wholly absent. Anterior antennae abruptly
curved in their outer part and densely setiferous, 6-articulate, the first 2 joints
much the largest, and together about twice as long as the remaining part, 4th
and 5th joints very small, terminal joint long and narrow. Posterior antenna'
with the distal joint fully as long as the proximal one, outer ramus scarcely more
than half as long, and provided with 6 seta), 4 of which belong to the distal joint.
Mandibular pal]) with the basal part comparatively short and broad, rami a little
unequal, the inner one being the larger, both clothed with simple sehe. 1st pair
of legs with the 2nd basal joint produced at the end inside to a conical process
carrying a strong detlexed spine, miter ramus narrow, with no seta inside the
middle joint, last joint somewhat larger and armed with 3 spines and a slender
seta; inner ramus about the length of the outer, but somewhat broader, proximal
joint without any seta inside, distal joint a little longer and narrower, and pro-
vided inside in front of the middle with a small seta, tip carrying 2 unequal

193

spines and a slender seta. Natatory legs all of the same structure, though slightly
differing in size, the 4th pair being considerably smaller than the other 2; outer
ramus in all of them rather narrow, with no seta inside the 1st and last joints;
inner ramus much coarser than the outer, proximal joint with a strong seta inside,
distal joint considerably larger, with 2 thickish setse inside, 2 others at the tip,
and a short spine outside near the end. Last pair of legs having outside a small
knob-like prominence carrying a slender hair-like bristle, and immediately inside
it another knob-like prominence tipped with 2 spines and representing the rudi-
mentary distal joint, innermost part of each leg forming a short lamellar expan-
sion carrying 3 subequal ciliated set3. Ovisacs very small and extended laterally,
each containing only one or two ova.

Colour whitish.

Length of adult female 0.50 mm.

Remarks. This form may be easily recognized from any of the other
Harpacticoida by the unusual appearance of the caudal rami, which are extremely
slender and curved outwards in a most peculiar manner, their apical setse being
extended straight laterally, not as usual behind. This peculiarity has indeed given
rise to the specific name divaricata here proposed.

Occurrence. Only 3 female specimens of this remarkable Copepod have
hitherto come under my notice. One of these specimens was taken at Bukken,
west coast of Norway, the other 2 at Farsund. In both localities it occurred at
a depth of about 50 fathoms, muddy bottom.

Fam. 12. Canthocamptidae.

Characters. Body, as a rule, slender, more or less cylindrical in form,
with no sharp demarcation between the anterior and posterior divisions. Rostrum
in most cases very small, and not distinctly defined behind. Anterior antennae
more generally 8-articulate, and distinctly hinged in the male. Posterior antennae
with the outer ramus comparatively small. Mandibular palp likewise in most
cases of insignificant size. Posterior maxillipeds terminating in a well-developed
clawed hand. 1st pair of legs more or less distinctly prehensile, the inner ramus
being generally longer than the outer and bent in its outer part. Natatory legs
more or less slender, with the outer ramus always longer than the inner, which
in some cases becomes much reduced. Last pair of legs in female more or less

194

lamellar, with the distal joint generally well defined and the proximal joint ex-
panded inside. Only a single ovisac present in female.

/.'<///"//.-.- To this family I refer a number of genera, which, as regards
both the external appearance and the structure of some of the appendages, exhibit a
perplexing similarity to the more typical Dn^m-ailr (Ami>h'i<i*<-nx). though differing
materially in a tew points. Thus in all the forms only a single ovisac is present
in the female, and the rostrum never attains that full development which is charac-
teristic of the D'uixiicr'iiln'. being in most cases reduced to a very minute im-
mobile point. The outer ramus of the posterior antenna 1 is very small, and this
is also generally the case with the nuvndibular palp. As to the legs, the 1st pair
are often built upon a very similar type to that in the Dio*ttrritln'. the inner ramus
being generally longer than the outer, and more or less prehensile. On the other
hand, this ramus, in the natatory legs, is as a rule less fully developed than in
the f)i<j*<in-i<l,r. The present family is represented both in fresh water and in
the sea, some forms also in brackish water.

Gen. 4'2. CanthOCamptllS, Westwood, 1N3().

Syn: Canthocarpus. Haird.

Generic Character*. Body slender, eylindric in shape, and very flexible,
with the anterior division only little broader than the posterior. Cephalic segment
of moderate size and not very deep; rostral projection very small, and rudiment-
ary. Epimeral plates of the 3 succeeding segments comparatively small and
rounded behind ; last pedigerous segment scarcely narrower than the preceding
me, but without true epimeral plates. Urosome well developed, with the segments
-pinulose at tin- hind edge ventrally and laterally, genital segment in female large
and imperfectly divided in the middle, last segment short, with a distinct anal
opercle edged with regular spimilus. Caudal rami slightly produced and provided
outside with 2 hair-like bristles, apical seta' normal. Kye well developed. An-
terior antenna' more or less slender, 8-articiilate. tlm>e in male strongly hinged.
l'i!eriur anteniKi- with the outer ramus rather small. Inarticulate, distal joint the
-mailer. Oral parts on the whole poorly developed. Mandihiilar palp simple,
Inarticulate. .Maxilla' without distinctly defined exopodal and epipodal plates.
Anterior maxillipeds pro\ided with only "2 digitiform lobules inside the unguiferous
joint. Posterior maxillipeds normally de\e] ( .prd. 1st pair of legs with the inner

195

ranius distinctly 3-articulate and longer than the outer, being more or less bent
at the end. Natatory legs very slender, with the inner ramus much shorter than
the outer and in the 2 anterior pairs 3-articulate, in 4th pair biarticulate ; those
in male having the inner ramus in all the pairs, or only in the 2 anterior ones,
transformed. Last pair of legs with the distal joint comparatively small, inner
expansion of proximal joint more or less prominent, marginal setae of both joints
rather coarse, spiniform.

Remarks. This genus was established as early as the year 1836 by
Westwood, to include the well-known fresh-water species, C. staphylinus Jurine.
In recent times, several new species have been added, most of them likewise from
fresh water; and a subdivision of the original genus into several nearly-allied
genera has been carried out by some recent authors. The present genus is there-
fore now generally taken in a much more restricted sense than previously. It
still comprises several well-defined species, 2 of which belong to the Norwe-
gian fauna.

123. Canthocamptus staphylinus (Jurine).

(PI. CXXVI & CXXVII).
Monoculus staphylinus, Jurine, Historic des Monocles, p. 74, PI. VII, figs. 1 17.

Syn: Canthocamptiis minutus, Baird (not Glaus).

Specific Characters. Female. Body moderately slender and slightly con-
stricted in the middle. Cephalic segment scarcely longer than the 3 succeeding
segments combined; rostrum forming a very small triangular projection between
the insertion of the anterior antennae. Urosome a little shorter than the anterior
division, and having the segments rather sharply marked off from each other,
genital segment exceeding in length the 2 succeeding ones combined, last segment
much the smallest and produced at the end on each side in a short dentiform
projection, anal opercle rather prominent, semilunar, and armed with a regular
row of simple spinules. Caudal rami about the length of the anal segment, being
twice as long as they are broad, and of uniform width throughout, the outer one
of the 2 middle apical setae comparatively short and very distinctly denticulate,
the inner rather elongated, exceeding half the length of the body. Anterior an-
tennse comparatively slender and elongated, exceeding in length the cephalic segment,
and clothed with rather short setae, terminal part very narrow and about the length
of the proximal part. Posterior antennae of moderate size, proximal joint with 2
widely separated setae on the anterior edge, distal joint of about the same length,

L96

outer rainus scarcely half as long, and carrying 4 short setae, 3 of which belong
to the last joint. 1st pair of legs with the outer ramus about the length of the
1st joint of the inner, last joint somewhat larger than the preceding one, and
armed with ~2 spines and 2 geniculated setae ; inner ramus twice as long as the
outer ami very slender, 1st joint about the length of the other 2 combined, the
latter somewhat unequal, the terminal one being much the longer and very nar-
row linear, carrying on the tip a sleixh r denticulated spine, a long seta, and a
small hair-like bristle. Natatory legs exceedingly slender, inner ramus of the 2
anterior pairs extending considerably beyond the 2nd joint of the outer, that of
4th pair to about the middle of that joint. Last pair of legs with the distal
joint narrow oblong in form, and armed with 5 spines, 3 on the outer edge, one
very small one on the inner edge near the end, and one very long apical one; inner
expansion of proximal joint broadly rounded, and not extending to the middle of
the distal joint, marginal spines 5 in number and somewhat unequal. Ovisac
short and rounded, sub-globose in form, never extending beyond the end of the
urosome. Spermatophore attached to the genital opening very large, sabre-like,
and often of a very dark brownish colour.

Mulr not much smaller than female and easily recognizable by the pre-
hensile anterior antennae and the complete division of the anterior caudal segment.
1st pair of legs of exactly the same structure as in the female. Inner ramus
of all the 3 succeeding (natatory) pairs conspicuously transformed, that of 2nd
pair rather slender, with the outer 2 joints imperfectly defined, the last one armed
inside with a short deflexed spine, and carrying on the somewhat obliquely rounded
extremity 3 setse, the outermost of which is much elongated; that of 3rd pair
considerably shortened, middle joint produced at the end inside to a strong de-
flexed mucroniform process, last joint short, oval in form, and tipped with a small
bristle; that of 4th pair with the distal joint produced at the end outside to a
short spinifonn projection, inside which 3 closely-set, long, curved and somewhat
spiniform seta are attached. Last pair of legs smaller than in female, distal joint
of a similar shape, but provided inside near the base with an additional slender
spine: inner expansion of proximal joint quite short, and provided with only "2
unequal spines. Genital lobes armed with 2 spines and a hair-like bristle.

Colour somewhat variable, in some cases yellowish green, in others more
reddish; that of male more generally of tlie last-named colour.

Length of adult female about 1 mm.

/.'<///'///>. It is very probable, that the Cyclops minutus of 0. Fr. Miiller
refers to the present species, and that thus the identification made by earlier
author^ is quite correct. Hut in any case the name niiinitii* would be very inap-

Diosaccidae.

Copepoda

Harpacticoida

PI. cxm.

G.O.Sars autogr. Norsk lithgr. Ofncin

Amphiascus phyllopus, G.O.Sars

Diosaccidee.

Copepoda

Harpacticoida

PL CX1V.

30.Sars autogr.

nanus .

exiguus, G.O.Sars.

Norsk lithgr. Officin

Diosaccidae.

Gopepoda

Harpacticoida

Pl.CXV.

G.O.Sars autogr Norsk lithgr. Officin

Amphiascus productus, G.O.Sars.

Diosaccidae

Copepoda

Harpacticoida

PLCXVT.

G.O.Sars autogr Norsk lithgr. Officin

Amphiascus tenellus, G.O.Sars.

Diosaccidae.

Copepoda

Harpacticoida

Pl.CXVII.

G.O.Sars autogr. Norsk lithgr. Officin

Amphiascus linearis, G.O.Sars.

Diosaccidae.

Copepoda

Harpacticoida

P1.CXV1II.

/

m - il "

e.O.Sars autogr . Norsk iithqr. Officin

Amphiascus sinuatus, G.O.oars

Diosaccidae.

Copepoda

Harpacticoida

PL CXK.

,

G.O.Sars autogr

Stenhelia gibba, Boeck

Norsk lithgr. Officin

Diosaccidae.

Copepoda

Harpacticoida

P1.CXX.

G.O.Sars autogr.

I.Stenhelia gibba, Boeck

(continued)
2. " proxima, G.O.Sars.

Norsk lilhgr. Officin

Diosaccidae.

Copepoda

Harpacticbida

PL cm

'-^

--

' ^:

G.O.Sers autogr

Stenhelia semu la, (Scott).

Norsk Ijfhgr Officin

Diosaccidae.

Copepoda

Harpacticoida

PL CHE

,:

i

{(- m

I " ^

- Alt __-- i ff tTj*fl TTJ**-T* **^?-W|fc

V /

GO.Sars auto a r.

Stenhelia palustris, (Brady).

Norsk lithgr Officin

Diosaccidee.

Copepoda

Harpacticoida

pi.cxxi.

f

G.O.Sars autogr Norsk lithgr Officin

Stenhelia refiexa (Brady)

Diosaccidae.

Copepoda

Harpacticoida

PI. CXW.

;!

- J ;

: i : .

G.O.Sars autogr. Norsk Itogr. Officin

i.Stenhelia Giesbrechti, (Scott).

n

Normani, (Scott).

Diosaccidae.

Copepoda

Harpacticoida

Pi. CXXV

G.O.Sars autogr Norsk lithgr. Officin

I.Stenhelia longicaudata , Boeck

:.. _>_ n n o^

Canthocamptidae.

Copepoda

Harpacticoida

PI. CXXVl.

G.OSars autogr. Norsk lithgr. Officin

Canihocamptus staphylinus, (Jurine).

Canthocamptidae.

Copepoda

Harpacticoida

PL CXXVU

GOSars antcgr

~ i / i >Norsk lithqr. Officin

Canthocamptus staphylinus, (Jurine).

(continued).

uopepoaa

Canthocamptidee. Harpacticoida

PI. cxxvm.

G.O.Sars autogr.

Canthocamptus minutus, Glaus

Norsk lithgr.Offlcin

AN ACCOUNT

OF THE

CRUSTACEA

NORWAY

WITH SHORT DESCRIPTIONS AND FIGURES OF ALL THE SPECIES

BY

G. O. SARS

VOL. V

COPEPODA

HARPACTICOIDA

PARTS XVII & XVIII

CANTHOCAMPTID^E (continued)

WITH 16 AUTOGRAPHIC PLATES

BERGEN

PUBLISHED BY THE BERGEN MUSEUM

SOLD BY

ALB. CAMMERMEYER'S FORLAG, CHRISTIANIA

1907

197

propriate for the present form, which in reality is much the largest of all the
known species of this genus. It is for this reason that recent authors now gener-
ally apply to the present species the name stavliylinus, proposed by Jurine,
though it is of somewhat later date, the name minutus being confined to another
species so named by Glaus. In every case the present species must be regarded
as the type of the genus Canthocamptus and at the same time as the type of the
whole family Canthocamptidct.

Occurrence. This form is very common in the neighbourhood ofChristi-
ania, especially early in the spring, and in all probability is distributed over the
greater part of the country. It generally occurs in shallow ponds and ditches
together with other fresh-water Entomostraca, more rarely in larger lakes. Male
and female specimens occur with almost equal frequency, and are often found tied
together in copula, the female being grasped by the anterior antennae of the male
at the base of the caudal seta?. The swimming movements of the animal are not
very rapid, and are effected in a somewhat reeling manner. It also moves with
great dexterity on the bottom, or along the leafs and stems of aquatic plants, by
curving and twisting its very flexible body, and applying its legs as levers.

Distribution. British Isles, Sweden, Denmark, Central Europe, North
America, Novaja Zemlja.

124. Canthocamptus minutus, Glaus.

(PI. CXXVIII).
Cantliocamptus minutus, Claus, Die freilebenden Copepodeii, p. 22, PI. XII, fig. 1, PI. XIII, fig. 2.

Syn: Canthocamptus lucidulus, Kehberg.

Specific Characters. Female. Body slender and elongated, sublinear in
form, being of almost equal width throughout. Urosome with the segments less
sharply marked off than in the type species, genital segment scarcely longer than
the 2 succeeding ones combined, last segment without any dentiform projections
at the end outside, anal opercle somewhat less prominent and edged with about
12 spinules, which are all bifid at the end. Caudal rami scarcely as long as the
anal segment, and conspicuously thickened in the middle, the outer edge being
very convex and provided with 3 small denticles and 2 hair-like bristles, tip
somewhat exserted and obliquely truncated, apical setss rather slender, the inner-
most but one about twice as long as the adjacent seta on the outer side. An-
terior antennae much shorter than in C. stapliylinus, otherwise of a very similar
structure. Posterior antennte and oral parts likewise of essentially the same structure

20 Crustacea.

198

as in the typical species. 1st pair of legs with the outer ramus of moderate
size, seta attached insult- the middle joint of unusual length, last joint almost as
long as the other 2 combim-d. and earning at tin- tip 2 spines and 2 geniculated
B; inin-r ramus only slightly exceeding in length the outer, and less distinctly
pn hensile than in the typical species, 1st joint much shorter than the other 2
combined, last joint somewhat longer than the middle one. and. as in ('. s^//////-
//>///>. carrying on the tip a slender spine, a still more slender seta, and a \cr\
small hair-like bristle. Nataton legs comparatively less slender than in that
species, \vith the inner ramus shorter in proportion to the outer, though of the
structure characteristic of the genus. Last pair of legs resembling in shape those
of (\ staphylinus, inner expansion of proximal joint, however, comparatively larger,
extending beyond the middle of the distal joint and provided with <i marginal
spines, the 2 outermost ones much shorter than the others. Ovisac oblong oval
in form, extending to the end of the urosome.

Mule with the inner ramus of 2nd pair of legs conical in form, and hav-
iii'_ r the outer 2 joints wholly continent, sub-apical spine wanting; that of 3rd pair
transformed in a similar manner to that in the male of (\ *f<tj>ltt/Hntix. the
mucroniform process of 2nd joint, however, still longer, terminating in a very
slender point: inner ramus of 4th pair not differing from that in the female, ex-
cept in the smaller number of setae, that of the 1st joint and the proximal one of
the last joint being absent. Last pair of legs with the distal joint comparatively
smalh-r than in the male of C. stttjilti/liiinx. differing also somewhat in shape.

Colour whitish.

Length of adult female 0.56 mm.

L'I ///"//.-. -This form was first recorded, though rather imperfectly, b