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VOL. Ill, PART

A. ]7. HANSEN: CRUSTACEA MALACOSTRACA (IL)

CONTENTS:

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PUBLISHED AT THE COST OF THE GOVERNMENT

BY

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THE DIRECTION OF THE ZOOLOGICAL MUSEUM OF THE UNIVERSITY

COPENHAGEN.
H. HAGERUP.

PRINTED BY BIANCO LUNO.

1913.

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THE DANISH INGOLF-EXPEDITION.

VOLUME Il.

3.

CRUSTACEA MALACOSTRACA.

BY

H. J. HANSEN.

WITH 12 PLATES AND A LIST OF THE STATIONS.

COPENHAGEN.

PRINTED BY BIANCO LUNO.

1913.

Il.

CONTENTS.

Crustacea Malacostraca.

IV. The Order Tanaidacea.

Page
ALON rite cs sd sigs ahs tao aye Gth AER SeuldRwed wire I
Rien Pee PATRI Co tev Sern a ola sone Ret Dba he wre w e I
Results and Questions..................... ees SOBRE. 3
Acme timate” Collectoti 5 5) skies ic aaa s tu eave ss 3
B. Geographical and bathymetrical Distribution ...... 4
C. Sexual Differences in the Tanaide................. 5
D. Some morphological Features in Agathotanazs n. gen. 8
E. On the naming of Segments and Joints........... 8
F. On generic and specific Characters ............... 9
RNAS sO Cig Dia ys sree sic ss ae vs ge PRG ee aye web oce bee)
Apseides: Teach x i025) ees ss Pee chat abe bens ay 10
1. Apseudes spinosus M.Sars......2........05 000s 10
2 es DICEAME MM es Ss ws) s veh ee «8 ads II
S —- _cspsaanan > Sas Saree Sept ac ie pene eh I2
4. — gracilis Norm. & Stebb............. 13
V4 — A CUTOREIMTAS LOT folded ok ns woot oan. 08k 15
wpAyrapus Norm, GG. OFS aPS iio ec sas sie ves 16
6 — GNOMAMS GS. COS RES i 55 oka oe ose he 16
@ — EEA OO ALB Ca a Ss SE ON Bick wicks 17
8 — tudes Norm. & Stebb................. 18
MARES AUS, 0 APSR ERE che aS ETNA Papin deka dg be 5.8 taldleresep ee pce 18
PNOOPIIAIS BROMO BETS yor sty 2556.2 Ls Cai food ene 18
9 — serratispinosus Norm. & Stebb......... “18
10 — Rastiger: NOtm.<& Sth bio. o es ga ecs snes 19
ii — PAP ONEME TS Bose ds aR ee Ue eis 20
FMEROLASUNES Cr, CCST EO) a ci9/5.5 sas Ui s'e oh ne dene ey 4 sie 21
120 — BVOCMUARGICUS DIBP ho iv ee be ea es 21
PT PO STB) REN Os Ih ee ra 22
13. — Cavolinit H.Milne-Edw............... 22
Sea eCCET MEN eee OPI Boss cdc otc Bo Rad ewes PRS 23
14. — forcipatus Lilljeborg................. 23
15 = BPR Eee cee See Seis ae ay wate 25
16. — Lijeborgt GO: Sars... ees 27
17 = OOMMIEO ECB, ea aidiys Mic on niece) Onala acs 29
Toes Offense TREN see vlna ge eo 30 |
19 — WREDOT Me BUT BO LC ek ee ac hie ees 33
Paratanats: Dane 2 RIP Aes aes ETS BEE Seis 34
20. — Balet, Gu Ge Bee ens ene aii chews, 08 35

IL.
Page
i paitanars GO SAS. 3. oes isi 5 ands Apelagasee He 35
21. — SPOR ATLIS BORD Re ole hive weweiec + Oh ae 36
22, — MACTOCEPRGAD. BDi. 56.0 5aee sd ae itaw sae 38
23. — PUA CP DG AB a atch cin a pam itis ons oe Mee 39
24. - OF TE DES TEE Bein acco anle ener auch eae Sn 40
. 25. MUCTONALUS NA BP... 2... cee ecicccce cee 42
26. — FAAOEME | Bh Be a Sa ates Magers Wieis ee onsis 44
27% — De THRE NBD oes ive ain vias ok 45
eee Er cais4s ie 1 Py? pa) mara eee Weld (Ue a ape at 46
29. — WGPTOOES DSB Dee Sic ate gt ec dee Sane 48
RG is trispinosus 0. SP. ........+.. Sox's | eae 49
3I. — PLOFURAUS Ne BD er oor oe sua eis sae 51
32, — SPECOUAE TB oii peek e vee eS 53
- 33. — PF ONEES TY, SMe chai soca ied enoe a te eels 54
34. — Dlebejus: te 8 pest: Sov inie SS 56
355 — INBIRIDES WS. SPs ii55 ieses peare tte Se eo 57
36. -— fiumarchicus G. OVS aTS8. .. 2... eects ss 58
37, PRAMS TN BD gins. pos ere hk OREN Ce ae 59
38. — COrnuius GUOCS BIS 225 eh. eR ee 61
39. — SVUABS te SD ok, Paste aiokd design te eesie te 62
TARULROMIMIOS. MDE Berg ood | IAD ge LEY vac 63
40. — PROOUE Ds SPe i cw one acs ce ncy peter ore 64
Leptognathia G.O.Sars....... pO pede. erate ae OF Serie 65
41 — MUPSCEPEE Be BBL SLY «unin debs gee 66
42, — WOES, Eas fo Bae say cube tiga si es ,kwe wie welt 68
43. — PIQHHS BT OVEL. moa tas Sea wee Beer 70
44. — Hansent. Venh OLfenie. 5 aise Bs aes 71
45. — longiremis Lilljeborg ................ 74
46. — TEPPER Die ns Goce hase s Saeou se Rt 76
47. = OP GLAAGIG De BD Ss eee eto, bee ee ee 77
48. — PIPER OSD el aia TERED ole Hecate 78
49. — RONEN. STR Sis wiee mas REN 79
50. — QPMAA BES Pk 125.8 Se es 80
51. — Agtdr apie 8: O05) 6a oe a Pe ae se 81
52... — PUBEP ERIN Ts BD 5 ec te ia age 5 82
53. — UNCINAA HBP. ak ale le eee 83
544 — NANCE BD. BPs. <0 6S G eas fhe eels ESS 85
55. — SUOBGHANS- TL SD 6 <a visa op nies alee s + 87

587997

Page
56. Leptognathia tenella n. SP. ... 2... cece cee ee eee ee 88
57. — WERET UMS DS D5 iio cases eae FSS 89
58. — ACORERST CFA. BD eo So es Ka aa ees gI
59- — breviremis Lilljeborg............
60. — CT OSSE TE BR 8 ae sig ts ea eS 95
61. -- POMe DISD we cat eevee ke 96
62. -- WIAA De BDO og obese Tea nee TT 98
63. — Profsinada Be BPS wi. Haaecasc tr wala 99
64. — LALFEMES DS EPs. Soi a 5 Sao ose Hales 101
65. — ACRES DB Dec's ce ae ee 102 |
Haplocope: G. OFS @8 855 2.). sict ie ine se SRO aa ea 102
66. — VMEATEE DOB De oie hig. Sore * be a eee bal eee Gee 103
Lepr gna hill DAG OMe.) scichis $5 Reau.ve sta ven eeas 104
67, — QOVESE TBD 50-5 wrcsce ae nia tise wae tare 104
Crypiocope (a: OCS OY 8s cei a enn ee ea 106
68. — arctica TTP, el ccue. eois as GS depele oe arte 106

g2

69. Cryptocope Voringiti G.O.Sars................ 109
70. _ arctophylax Norm & Stebb....... IIo
Tanaella Norm. & Stebb........ (hin ate a ee ee oy 113
716. OCRI ECO BE BPS Sse Soe esate ae 113
72. — _ unguicillata Norm. & Stebb............. 115
SOrOneyIuFE SSO! BRO eRe he eee 116
735 — cylindrata G.O. Sars... 22.2.0... ccs 116
74. — INSEE ARSE TI sng oie eg eas hoa 118
Stone gy laerella M.S ORS 6s Ck shies 6a pease in 120
75. — INGUVIEG- DnB Pe = on Re a eis ck Sask 120
LGEANALTATUA Dy PON. KH. Soe Fae a es 121
76. — INSIOUES TBP S 5:5 ke pea tele epee ee es 122
7 subtilis n. sp. ..... p< iran APR Ae ie ata te 124
| 73.0” CUO IES The BAIS ns Chee ee ore kos 125
| Explanation of the: Plates 0. 2545s 2 eS eee ee 127

Crustacea Malacostraca. II.

By

H. J. Hansen.

IV. The Order Tanaidacea.

Introduction.

efore entering on the subject of the present paper I may refer to the “Introductory Remarks” in
B “Crustacea Malacostraca I” published in 1908, because they contain various statements that need not
to be repeated here. In that chapter I explained the limits of the area investigated by the “Ingolf” and
other Danish expeditions to our northern dependencies; the principal sources (apart from the “Ingolf”) for the
material examined were enumerated and the principles followed as to “occurrence” and “distribution”
were laid down. Zoologists wishing to get some information on these and allied topics may find them
in the paper mentioned. :

Our earlier knowledge of the Tanaidacea inhabiting the seas around Greenland, Iceland and
the Feeroes was poor. Only 9 species were known, 2 of which belong to the family Apseudide, 7 to
the Tanaide. I am, however, inclined to think that no Carcinologist would have supposed that it
might be possible to discover more than ten or fifteen new species within that area. But in the
present paper I enumerate 78 species, all, excepting one, captured by Danish expeditions, and 52 of |
these species are new to science. The “Ingolf’ has secured 71 of the species, but of these 13 have
besides been taken by another Danish expedition or by two or more zoologists; 3 species have been
gathered only by the “Thor” (Dr. Joh. Schmidt), 2 species exclusively by the second Amdrup-Expedition
(Mag. sc. Soren Jensen) and a single species by other zoologists. In proportion to the number of
species of Tanaidacea hitherto known from Norway, from Great Britain or from all seas together the
“Ingolf” collection is so astonishing, that some special reason may be looked for; it may be of
interest to attempt a discussion of the topic, and it may be possible to point out some results of
more general significance. Finally a treatment of some other results and questions may be inserted

before the purely systematic part.

On the Literature. -

The earlier literature until the year 1881 comprises a good number of papers, but most among
them dealing with only a single form or with some few species; the largest and most valuable of
these contributions were written by H. Kréyer (1842) and W. Lilljeborg (1865). But in 1881 G. O. Sars
published his paper: Revision af Gruppen: J/sopoda chelifera (Arch. Math. og Naturv. Bd. 7), which is

epoch-making in the history of our order. He divided it — he named it a group — into two well-

The Ingolf-Expedition, IIL 3. I

reas eae

2 CRUSTACEA MALACOSTRACA. II.

founded families, Apseudidee and Tanaidze, and pointed out their distinguishing characters; he established
nine new genera (only five had been previously described); he enumerated nearly all species described
from any ocean, and he added short descriptions of all species seen by him, redescribing a good
number of species already made known and establishing twenty-three new species. He enumerated
in all 3 genera and 14 species of the Apseudide, 11 genera with 46 species of the Tanaide, in all
14 genera with 60 species. But 4 species among the Apseudidze were ~omina nuda given by Norman,
and Sars had overlooked a single species of Afsewdes established by Willemoés-Suhm and two species
of Tanaidz established respectively by Nicolet and Bate. The result is that in 1884 59 species (not
counting mere synonyms) of Tanaidacea had been established.

In 1886 G.O, Sars published his important paper: Middelhavets Saxisopoder (/sofoda chelifera),
which contains elaborate descriptions with numerous excellent illustrations of seventeen species, all briefly
described but not figured by him in 1880. And in his splendid work: An Account of the Crustacea of Norway,
Vol. II, Isopoda (the parts on the Tanaidacea were edited in 1896—g7) Sars published new descriptions and
eighteen plates with figures of the Norwegian Tanaidacea, in all 28 species. By the three papers enumer-
ated Sars has laid down a very broad foundation for future study and illustration of the animals, and
he has done far more for the furtherance of our knowledge of the order than any other author.

Since 1881 about twenty-four zoologists have published descriptions of new species, sometimes
besides of new genera, of Tanaidacea. Among these prominence must be given to the two English
zoologists A.M. Norman and T.R.R.Stebbing, because in a valuable paper (On Crustacea Isopoda ...
1886) quoted several times in this report they gave good descriptions with numerous figures of
17 species (1 valid new genus), 13 of which were new and the majority even deep-sea forms; in other
papers each of these two authors has described and figured some other forms. — In the Challenger
Report Vol. XVII (1886) F. E. Beddard established 4 new genera and Io new species, most of them
interesting antarctic or deep-sea forms; unfortunately his figures are somewhat poor. — A. Dollfus has
published preliminary descriptions, with some figures, of about 14 valid new species and 1 new and
valid genus; in several papers published in later years Miss Harriet Richardson has established 2 new
genera and several new species, mostly American.

In order to arrive at a fair idea of our knowledge of genera and species established before
the middle of 1912 I have inspected the Zoological Records since 1877 and besides looked over the vast
majority of the papers. I have attempted to count the genera and species hitherto established, excluding
of course the synonyms, but it was impossible to arrive at absolute certainty as to the number of
species, because in a few cases it cannot be made out whether a species is valid or ought to be
cancelled as a synonym, and some few species have been so poorly described that they can scarcely
be recognized with any certainty. But I am sure that the following numbers are nearly correct. '

The family Apseudidee comprises 8 genera: Apseudes Leach with 28 species, Apseudopsis Norm. with
2 species, Parapseudes Sars with 3 species, Sphyrapus Norman with 5 species, 7yphlapseudes Bedd., Letopus
Bedd., Kalhiapseudes Stebb. and Pagurapseudes Whitelegge, each with a single species. In all 42 species.

The family Tanaidze comprises the following genera: Meofanais Bedd. (Alaotanais Norm. &
Stebb.) with 5 species, Zawazs H. M.-Edw. with 17 speciesy Leptochelia Dana with 16 species, Heterotanars
G.O.S. with 9 species, Paratanais Dana with 9 species, Mofotanazs Richardson with 3 species, 7yphlo-

CRUSTACEA MALACOSTRACA. IL. 3

tanais G. O. S. with 16 species, Leptognathia G.O.S. with 14 species, Pseudotanais G. O. S. with
5 species, Cryptocope G.O.S. with 4 species, Haplocope G.O.S. with 2 species, Strongylura G.O.S.,
Anarthrura G.O.S., Mesotanats Dollf., Pancolus Richardson, Tanaissus Stebb., Tanaella Norm. & Stebb.
and Bathytanais Beddard, each with a single species. In all 18 genera with 107 species.

Thus the order Tanaidacea comprises 26 genera with about 149 species.

Results and Questions.
A. The “Ingolf’’ Collection.

According to the literature only 9 species have hitherto been known from the coasts of Green-
land and the adjacent deep-sea area; the number of deep-sea species secured North of Lat. 56° N. by
the English expeditions was small, and the excellent collector of small Crustacea Prof. G. O. Sars
captured only 8 species of Tanaidacea during the Norwegian North-Atlantic Expedition. Judging
from these and other facts every zoologist would have thought it to be a good result if the “Ingolf”
had raised the number of species known from the seas around our northern dependencies to twenty
or possibly twenty-five. But as already stated, the “Ingolf’ captured 71 species of Tanaidacea, some
other expeditions or travellers added 6 species, and a single deep-sea species enumerated in the
literature as taken by the ‘“Valorous” within the area in question was not found again. — Besides it
may be stated, that a good number of the new species were taken by the ‘“Ingolf? at several stations
and sometimes in considerable numbers. ;

Of the 78 species only 8 belong to the Apseudide, but 70 to the Tanaide. The animals
belonging to the Apseudidze are on the whole considerably or much larger than the Tanaidee and
consequently far less overlooked by collectors. But as only 8 species — 3 among them new — of
Apseudide were secured by the “Ingolf” and the “Thor”, while 42 species are described in the literature
from all seas together, the number of species from our northern area is not even one-fifth of species
hitherto established. As to the Tanaidz the result is very different; 106 species were known from
all seas, but the “Ingolf”, ete. captured 70 species, thus almost two-thirds as many as hitherto known.
And 49 species of the Tanaidz are new to science.

These excellent results are mainly due to a method of collecting introduced by me during
the first “Ingolf” cruise. A considerable quantity of the mud hauled up by dredge or trawl, or the
whole bottom material when its quantity was less considerable, was sifted under water in smaller
portions in a sieve clothed with silk gauze no.7 used by millers; the well-sifted contents of the sieve -
were put in alcohol and later examined at home in small portions, in water or alcohol, on the lower part
of a cheese-cover under a moderately magnifying lens, In this way hundreds of small animals, as
Tanaidacea, Asellota, etc., were gathered. Other deep-sea expeditions could certainly have arrived at
corresponding results if their methods of dealing with the bottom material had been more satisfactory ;
it may be considered quite certain that hundreds of species of small Crustacea etc. lived in the bottom
materials hauled up by the “Challenger” and later great European and North American expeditions

and were flushed into the sea again.
1*

4 CRUSTACEA MALACOSTRACA. II.

B. Geographical and bathymetrical Distribution.

The fact that the “Ingolf” alone raised the number of species of Tanaidacea inhabiting the
area explored from g to 72, thus to almost half the number of species known from the entire world,
proves with absolute certainty that our knowledge of this order is still in its infancy. But an exami-
nation of the list of localities for each species affords further interesting results.

The major part of the 149 species previously known were taken exclusively or generally in
depths from o to 50 or 60 fathoms, several species generally in depths from 50 to 200 or at most 300
fathoms, and scarcely twenty species — secured mainly by the “Porcupine”, the “Valorous”, the “Challenger”
and “lHirondelle” — had been found generally or exclusively in depths more than 300 fathoms, some-
times in more than 1000 fathoms, and the greatest depth recorded is 2050 fathorhs. But among the
52 new species established in this report about 44 were taken either most frequently or — and in
most cases — exclusively in depths exceeding 300 fathoms and often in depths between 700 and
1870 fathoms. Some species formerly taken in lesser depths were now found to be not uncommon in
considerable depths. Thus, the “Ingolf? discovered more than twice as many deep-sea species as
hitherto recorded from all seas together, and the great majority among them are small, less than
3.5mm. and generally 1.6—3 mm. long.

Another point of great interest is that the richest harvest was yielded by some of
the deepest stations in the warm area South and West of southern Greenland. At
Stat. 78 (South-West of Iceland) an enormous quantity of bottom material was hauled up from 799
fathoms and 9g species of Tanaidacea were found; at Stat. 32 (Davis Strait) the quantity of bottom
material from 318 fathoms was very large and rendered 8 species. But at St. 38 (entrance of the
Davis Strait) the bottom material procured from 1870 fathoms filled in sifted condition scarcely more
than a good tea-cup, and in that I found even 9 species. And two of the stations West of South
Greenland were still richer; the sifted material from Stat. 36, 1435 fathoms, was about a liter and
contained 11 species, while from Stat. 24, 1199 fathoms, I have 12 species of Tanaidacea. The last-
named station thus rendered 4 species more than the whole Norwegian North-Atlantic Expedition, about
half as many species as hitherto known from the Mediterranean; the harvest from the four deep-sea
localities Stat. 22, 24, 36 and 38 is in all 30 species, while Sars in his standard work from 1896—97
has only 28 species from Norway.

From all these statements we may safely draw the conclusion, that the deep sea with 1100 to
1870 fathoms in the warm area in the North Atlantic has a much richer fauna of Tanaidacea than
any large northern or tropical part of the Atlantic along the coasts and with depths from o to
100 fathoms. And as it seems very improbable that the deep sea near South Greenland is propor-
tionately richer than the deep sea of the subtropical or tropical Atlantic, the Indian Ocean or the
Pacific, we may infer that hundreds of unknown species of Tanaidacea inhabit the deep areas of the
Oceans, and that the fauna from about 300 and down to at least 2000 fathoms is much richer than
the fauna living in depths between o and 300 fathoms.

In the list of the ‘“Ingolf” stations we find thirty places with the temperature at the bottom
below zero; these stations belong to the cold deep-sea/area and their depth ranges from about 300 to

1300 fathoms, Of our Tanaidacea 8 species are exclusively from these stations. The warm deep-sea

CRUSTACEA MALACOSTRACA. II. 5

area is more difficult to define, but it may be proposed that the stations with a depth between 300
and 600 fathoms and the bottom temperature not below 3°, and all stations with depth from 600 to
1870 fathoms and the temperature above zero belong to that area. When we adopt this view it will
be found that about 38 species enumerated in the following pages were taken exclusively in this
warm deep-sea area, which consequently has a much richer fauna than the cold deep-sea area. A
somewhat small number of species (Sphyrapus anomalus G.O.S., Pseudotanais affinis H.J.H., Typhio-
tanais mixtus n. sp. Leptognathia longiremis Lilljeborg, L. ventralis nu. sp. L. breviremis Lilljebg.,
Cryptocope arctica H.J.H. and Strongylura cylindrata G.O.S.) have been taken both in the real cold
deep-sea area and at rather deep or very deep stations in the warm area; but with a single
exception (Zyphlotanats mixtus) all these species have besides been taken in depths of less than
100 fathoms either by the “Ingolf? or at Norway, at East Greenland or in the Kara Sea. — The
majority of the remaining species are forms living in depths less than 300 and frequently less than
100 fathoms. Some few species (as Leptognathia inermis n. sp., L. Sarsti H. J. H., L. subequalis n. sp.
and L. latiremis n.sp.) cannot be referred to any of the three categories just mentioned, but they seem
to be essentially cold water forms sometimes found in temperatures a little above zero; L. swbegualis

was once taken even in 318 fathoms in a temperature of 3.9°.

C. Sexual Differences in the Tanaide.

Adult males of species of the family Apseudide are frequently taken together with the
females, and I am unable to add anything to our knowledge of the sexual differences in this family.
Sars has published excellent figures of both sexes of the two Norwegian species Afseudes spinosus
M. Sars and Sphyrapus anomalus G.O.S., of Sphyrapus serratus G.O.S. and of a few species of
Apseudes from the Mediterranean. In the males the abdomen is generally longer in proportion to
the thoracic segments, the pleopods and their sete are longer, the flagella of the antennule and
antennze and the endopod of the uropods are longer and divided into a larger number of joints than
in the females; furthermore, the chelipeds of the males differ somewhat or very much from those
of the females, and sometimes the second pair. of thoracic legs show some difference.

As to the family Tanaide our knowledge of the males is still very imperfect and some inter-
pretations are erroneous; it is necessary to distinguish sharply between adult and subadult or immature
males. Sars has described the females of 26 species of Tanaidee from Norway, but he was acquainted
with really adult males of only 5 species, viz. Zanats Cavolinii M.-Edw. (7. tomentosus Kr. G.O.S.),
Heterotanats Oerstedit Kr.. Typhlotanais finmarchicus G.O.S., Paratanais Bater G.O.S. and Leptognathia
Sarstt H.J.H. (L. longiremis G.O.S., not Lilljeborg); he described also what he believed to be the
males of Anarthrura simplex G.O.S. and Pseudotanars forcipatus Lilljebg., but his animals were only
subadult males, not adult specimens, and at least the adult male of the last-named species (already
described, without figures, by Lilljeborg) is widely different from the subadult stage. Sars was aware
that his males of Strongylura cylindrata G.O.S. were “probably” immature, which in reality was
the case. In 1885 he figured the adult male of Cryftocope Véringii G. O.S.; in his paper on the
Mediterranean forms he figured the adult males of Zepfognathia brevimana Lilljebg., Heterotanats

6 CRUSTACEA MALACOSTRACA. IL.

anomalus G.O.S. and of species of Leptochelia, — Adult males of some few other species have been
described by Moore, Stebbing, ete.

A study of Sars’ descriptions and figures of adult males as compared with the corresponding
females is interesting. In Zanais Cavolinii M.-Edw. (7. tomentosus Kr., G.O.S.) female and male seem
to differ only by the chele, which in the male are very broad, strongly forcipate and without tubercles
on the fingers, while in the female they are rather slender, scarcely forcipate and with two tubercles
on the fixed finger. The males of all other above-mentioned forms differ much more. from their
females. In Heterotanats Oerstedii Kr. the male has the cephalothorax produced in a very long and
thin “neck”, the antennulz and the antenne are longer and thinner than in the female, the antennulz
five-jointed in the male, three-jointed in the female, and the chelipeds are quite anomalously shaped
in the male, normal in the female. The males known belonging to Paratanais, Typhlotanais, Lepto-
gnathia and Cryptocope differ from their females in many particulars: the antenne are six-jointed when
three-jointed in the female, seven-jointed when four-jointed in the female, and have besides in all
genera tufts of sensory hairs on three of the joints; the thoracic segments are conspicuously shorter
in proportion to carapace and abdomen than in the females; the chelipeds or at least the chelee differ
somewhat or considerably in shape and equipment from those of the females: the thoracic legs are
somewhat or considerably longer and more slender, the abdomen is larger, its pleopods longer with
longer setee and the uropods at least a little longer than in the females; finally in Paratanais the
eyes of the males are much larger than in the females. The males of Leptochelia differ from their
females especially in having much larger eyes, the chelipeds elongate with the chele very differently
shaped and the antennule divided into a good number of joints. (It has been stated that in the
males the mouth-parts are generally more or less reduced, but the majority of the males described
have not been very closely investigated in that respect). :

With a single exception (Cryplocope Véringit G.O.S.) all species of which the adult males
are known, inhabit comparatively low water, from the beach down to 30 or 50 fathoms. And according
to the sexual differences just pointed out the adult males of most genera differ in general aspect and
in several characters more from their own females than from males of other genera, and the differ-
ences between the two sexes of the same species are most frequently larger than the differences
between the female of that species and females of several other genera. The result is that not
unfrequently it is impossible with certainty to refer a male to its female, to determine specimens of
the male sex. '

While my material of females and immature specimens dealt with in this report is exceedingly
large, comprising probably a good deal more than a thousand specimens, I have very few adult
males. I establish a new species of Meotanais on a male about twice as long as any male or female
hitherto known of this family from any sea. Furthermore, I have ’5 males belonging to 3 species of
Pseudotanatis, 5 males belonging to 3 species of Leptognathia and a male Cryfpéocope, in all 11 specimens
referred by me to 7 species; the reference of males to five of these species is absolutely certain, but
two are referred with a little less certainty. Finally, I have still two males, one of which with a
peculiarly armed chela, but being unable to refer they to genus I found it useless to describe them.

But this enumeration of 14 adult males as compared with the enormous number of females and

CRUSTACEA MALACOSTRACA. II. 7

immature specimens of both sexes proves that adult males must be either. very rare or, and
much more probably, that they swim about and are therefore rarely taken with the trawl or the
dredge.

_ Immature or subadult males of many species were taken together with the females. In all species
with the pleopods quite rudimentary or wanting in full-grown females with or without marsupium
such subadult males are instantly recognized by having moderately developed or even somewhat large
pleopods; this is the case in several species of Leptognathia, in Pseudotanats forcipatus and P. Lilije-
borgt, in Agathotanats, Leptognathiella, Strongylura, Paranarthrura. In all these forms the subadult
males have the abdomen proportionately either a little or, as in Paranarthrura insignis n.sp., consid-
erably longer than the female. In the genera with the antennul four-jointed these appendages, and
especially their two proximal joints, are generally conspicuously thicker in the subadult males than in
the females, and in some species of Lef/ognathia (f. instance ZL. armata n. sp.) the antennule of the
subadult male are five-jointed, as the fourtii joint has its basal part marked off by an articulation.
In species of Psewdotanais or Leptognathia with the pleopods well developed in the female and in all
species of 7yphlotanais the antennule alone afford readily distinguishable differences between females
without marsupium and subadult males. In ZyAhlotanais the main difference is the thickness of the
two proximal joints and of a portion of the third joint; in Psewdotanais we find generally the basal
part of the third antennular joint somewhat thickened and besides protruding below.

It is a common rule that when a good material of full-grown females of a species is to hand,
the great majority are without marsupium, even when taken at the same station. But it is a curious
fact that in several cases some of the largest specimens without marsupium are a little longer than
the longest specimen with marsupium; this fact I cannot explain, but I am induced to think that
some reduction in size may accompany the development of the marsupium and the eggs. In females
with marsupium the ventral surface of the lamelligerous or of all thoracic segments is rather or quite
flat, in specimens without marsupium most frequently considerably convex, but specimens without
marsupium are sometimes found showing the ventral surface flat and on the whole showing an
appearance as if the marsupial lamellze had been lost, but whether this has been the case is imposs-
ible to decide.

In females without marsupium and subadult males of several species of 7yphlotanais and of
Leptognathia ventralis n. sp. the second thoracic segment is below, and generally at or not very far
from the front ventral margin, produced in a generally acute and sometimes large process directed
downwards and more or less forwards; in females with marsupium and in very few cases in female
specimens without marsupium (perhaps lost) but with the lower side of the thoracic segments nearly
or quite flat this process is either reduced in size and shape (Leftognathia ventralis) or lost (Zyphlo-
tanais). — In Typhlotanais microcheles G.O.Sars females without marsupium and with the ventral
side of the thoracic segments convex, the ventral process is found on all thoracic segments excepting on
the seventh (vid. “Remarks” on 7. gracilipes n. sp.) — In Paranarthrura insignis n. gen. n.sp. the
females without marsupium and subadult males have a conspicuous process on the ventral side of all
thoracic segments, but in females with marsupium only the process on the seventh segment has

been preserved.

8 CRUSTACEA MALACOSTRACA. II.

D. Some morphological Features in Agathotanais n. gen,

Among all the new species described in the present paper only one, viz. Agathotanais Ingolfi
n. gen. nu. sp. shows hitherto unknown features of more general interest. Both females without mar-
supium and subadult males are at hand (PI. VI, figs. 5a—so). In the female the antennz consist of a
single minute joint (fig. 5c); in subadult males this joint is considerably larger (fig. 5n). In all specimens
the seventh thoracic segment and all abdominal segments are immovably fused, but the limits between
the segments are tolerably indicated by fine furrows (figs.5b and 50). The pleopods are wanting in
the female (fig.5b); in the subadult males they are rather long, unjointed, very slender conical and
all coalesced, constituting a kind of pyramid with longitudinal furrows betwéen the pairs, and each
pleopod terminates in a few very short setee (fig. 50). The uropods are rudimentary, each being a
small, subtriangular joint without any distinct division (figs.51 and 51m).

Among these features the rudimentary state of antennee and uropods are mere reductions,
which yet are much stronger than in any other genus. The fusion of seventh thoracic segment and
all abdominal segments is still more interesting. But completely without parallel among Crustacea
is the fact, that in the subadult male all five pairs of pleopods are coalesced forming a single
somewhat long protuberance, and this fact is of importance for comparison with features found in

mouth-parts in a couple of groups of high rank of terrestrial Arthropoda.

E. On the naming of Segments and Joints.

Before entering on the systematic part it may be useful to say a little on the counting of the
segments and joints and the terms used in the descriptions.

As the first thoracic segment is always fused with the head and hidden beneath the carapace,
the apparently first segment is in reality the second, consequently it is here named the second and
its legs the second pair, while the first pair of legs, the chelipeds, as belonging to the cephalothorax,
are described separately.

The counting of the antennular joints presents no difficulty. But the antenne are less easy.
When the antennze of females are fully developed they contain seven joints, as is seen in many species
of Leptognathia. ‘The first joint is very short, frequently nearly triangular, as the posterior margin is
oblique and the upper margin very short or wanting; this joint is sometimes difficult to perceive and
I never describe it, but it must of course be taken into consideration by counting. The two next
joints are somewhat short and the third as a rule shorter than the second; in a couple of species of
Typhlotanais these joints are strongly armed below. Fourth and fifth joints are somewhat long, but
frequently, as in Zyphlotanais, in some species of Leptognathia, in Paranarthrura, etc., fused, constituting
a single long or very long joint sometimes with a vestige of division. Sixth joint is well developed,
seventh always very small. z

The thoracic legs have always the second joint long; the first joint is quite short but most
frequently discoverable. The “claw” on the sixth joint is composed of the seventh joint and the real claw,
and the limit or suture between these two parts is most frequently distinct. In the descriptions the

joints are named according to their real number.

CRUSTACEA MALACOSTRACA. IT. 9

The chelipeds are somewhat difficult. In Apsewdes a cheliped seems to consist of only five
joints instead of seven plus claw. But the presence of an exopod on the first joint proves that it is
the second (according to the earlier morphology), and from a comparison with the second pair of legs it
is evident that the long joint preceding the chela has been formed by the complete fusion of two
joints; finally, the movable finger of the chela answers to the “claw” in the following legs, thus con-
sisting of seventh joint and the real claw. In most genera of Tanaide the chelipeds consist of the
same five joints as in Afseudes, but in several forms, as in the male of Neotanais giganteus, in Cryfto-
cope Voringit and C.arctophylax and above all in Anarthrura (comp. Sars’ figures) we find a conspicuous
piece developed as a separate plate or (in Amarthrura) a large real joint between the usual “first”
joint and the body; this plate or joint is certainly the real first joint which in most forms of the
order is feebly or not marked off from the cephalothorax. As the chelipeds show such tangled
morphology I have abstained from applying the counting method when the joints to be described
must be indicated. Therefore I use some of the names applied by H. Milne-Edwards to the joints of
the legs in Decapoda; whether most of the joints in the legs’ of Tanaidacea and Decapoda can be
considered identical as to morphological value according to their number is another and very difficult
question not. to be discussed here. The apparently first and very conspicuous joint of the chelipeds
in most forms is named the basal; the real first joint in Avarthrura and the plate marked off in the
forms just enumerated is named the coxal joint. The joint beyond the basal is named the ischium,
but in most forms it affords no character worth mentioning. The next joint is named the carpus,
though morphologically it answers to meros and carpus; in the descriptions of the chela I speak of

hand and fingers, the hand going to the insertion of the movable finger.

F. On generic and specific Characters.

In this report I establish only three genera, all belonging to the Tanaide. Two of these are
well separated, but the third, founded on a single specimen, was established only because it fits badly
in the genera known, though it does not seem to possess any single really good generic character.
The big genus Leptognathia is divided into groups, and in the future it will certainly be divided into
three or four genera, but I think it better to postpone this splitting up until a good number of
unknown forms have been discovered, because the Carcinologist will then be more able to settle the
value of several characters, whether they may be considered of generic or only of specific value. And
here we fall in with a difficulty. It is. with good reason that Sars laid stress on the mouth-parts in
females (and immature males) as affording generic characters and especially on the development of
the mandibles and the shape of their molar process, if that is present. But of numerous new species
the material is very scanty or even consisting of only a single specimen, and in such cases an exam-
ination of the mouth-parts was postponed. Furthermore many. species are so small, that several
Carcinologists dealing with such animals are scarcely able to dissect the mouth-parts in such a way
that a good representation of the mandibles can be given. And by the examination of the mouth-
parts in various species of Lep/ognathia I found that two such species as L. swbegualis n. sp. and L. ven-

tralis n.sp., which are rather allied in most characters and may be referred to the same group, show

The Danish Ingolf-Expedition. III. 3. 2

Io CRUSTACEA MALACOSTRACA. II.

in the shape and equipment of the molar processes such differences as those judged by Sars to be of
generic value. The result is that the value of the shape of the molar processes as generic characters
is lessened both from a scientific and a practical standpoint.

Though the descriptions of species published by G.O. Sars, Norman and Stebbing on the whole
must be considered good, some of the characters in the family Tanaide used by these authors are
scarcely sufficiently sharp, as a larger number of species have been discovered and it can be proved
than hundreds of species are still undiscovered. While drawing the figures I found it necessary to
use the ocular micrometer very much in order to figure as exactly as possible not only the relative
length of the segments and of the joints of all appendages, but besides the exact proportion between
length and breadth or depth of the joints of the chelipeds, the antennule and the peduncles of the
uropods. Very frequently it is stated in the following pages that a joint is somewhat less than twice
as long as deep or more than half as long again as another joint, etc., and in all such and several
other cases the statements are founded upon measurements. As some slight individual variation exists
and in some cases may be more pronounced, the proportions stated may sometimes be only approxim-
ative, but in spite of such variation I thought it better to give statements based on measurements
than such founded on measuring by the eye.

Especially the relative length and breadth or depth of some of the joints of the chelipeds
afford excellent specific characters, but care must be taken that the joints are seen exactly from the
side, as an oblique position of a joint produces an erroneous impression as to the relative dimensions.
The shape and length of all or of the three proximal joints of the antennule are also valuable. The
processes on the ventral side of the abdominal segments in Cryplocope Véringw G.O.S. and C. arcto-
phylax Norm. & Stebb. were pointed out in the literature, but in many species of Zeptognathia the
presence or absence of ventral tubercles or of a peculiar process afford valuable characters. But it is
scarcely necessary to say more on these topics, as the perusal of a few descriptions of species belonging

to different genera may elucidate the methods applied.

Fam. I. Apseudide.

This family comprises eight genera, but only two are represented in the collection.

Apseudes Leach.
In the literature twenty-eight species have been established. The “Ingolf’ captured three

species, one of which is new; furthermore two species, both new, have been secured by the “Thor”.

1. Apseudes spinosus M. Sars.
1859. Rhoéa spinosa M. Sars, Forh. Vid. Selsk. Christiania for 1858, p.30. _
1886. Afpseudes spinosus Norman & Stebbing, Transact. Zool. Soc. London, Vol. XII, Pt. IV, p. 85,
Pl. XVII, fig. 1. a
! 1896. “= a G. O. Sars, Account Crust. Norway, Vol. I], p.7, Pls. III.

CRUSTACEA MALACOSTRACA. II. II

Remarks. As to this species I refer to Sars’ description and good figures. It may only be
mentioned that the largest of the females measures 13.8 mm. and was taken by the “Ingolf”; the largest
male, 12mm. long, is from Lat. 60°5' N.

Occurrence. The “Ingolf has taken this species at a single station:

West Iceland: St. 87: Lat. 65°02.3'N., Long. 23°56.2’ W., 110 fm.; 7 spec.

The “Thor” has secured it at 3 stations:
South of Iceland: Lat. 63°46’ N., Long. 22°56’ W., 80fm.; 1 spec.
eee eS Lat. 63°15’ N., Long. 22° 23’ W., 114—172 fm.; 5 spec.
South-West of the Feeroes: Lat. 61°15’ N., Long. 9°35’ W., 400—soo fm.; numerous spec.

Distribution. The species occurs along the whole coast of Norway, from Vadso to Christi-
ania Fjord, in depths from 30 to r50fm. (G.O. Sars), and even 180 fm. (Norman). It has been taken
off Bohuslan (Lilljeborg), in the eastern part of Kattegat, 17 to 30 fm. and in Skager Rak, 70 to 226 fim.
(H. J. Hansen). Between the Shetland Islands and Norway it has been taken two times by Cand. mag.
Ad. Jensen (“Michael Sars”) in 1902: Lat.61°0' N., Long. 2°35’ E, 150fm., temp. 7.9°, 1 spec., and Lat. 60°
5, N., Long. 3° 42' E., 190 fm., temp. 6.1°, 21 spec.; the “Thor” secured it near the Orkney Islands:
Lat. 58° 32’ N., Long. 4°18’ E., 150fm. ‘Tattersall has enumerated it from three places West of southern
Ireland and in such depths as 293, 320 and 375 fm. and according to Norman & Stebbing it was
taken off $.S. W. Ireland in 725 fm. — According to Norman Afseudes Koehleri Bonn., established on
a specimen from the Bay of Biscay, is to be cancelled as a synonym to A. spinosus; but judging from

Bonnier’s drawings that reference is still somewhat doubtful.

2. Apseudes vicinus n. sp.
(Pl.I, figs. 1a—rc.)

Immature Female. Allied to A.sfzmosus M. Sars, but differing in a number of features. —
The eye-lobes (fig. 1a) are more produced and more excavated in front than in A. sfzmosus, with the
result, that the transverse portion is very short and the outer process long, acute; the lateral process
behind the eye-lobe is more conspicuous than in the form mentioned, with the anterior margin
somewhat arcuate and the outer angle acute and a little produced. The lateral margin behind last-
named process is nearly straight excepting in front. The upper surface of the carapace with the
transverse furrow very distinct, long.

The antennule in the main as in A. sfimosus; the first joint with the proximal half of its
inner margin serrate; the outer flagellum 8-jointed, the inner 4-jointed and somewhat more than half
as long as the outer. Antenne with the flagellum 7-jointed; the squama reaches the end of the
penultimate joint of the flagellar peduncle.

Chelipeds (fig. rb) nearly as in A. spimosus, but the lower margin of the carpus is somewhat
longer than that of the ischium while in A. sfznosus the lower margin of the carpus is shorter than
that of the ischium and provided with two teeth not found in A. vicinus.

Thoracic segments somewhat longer in proportion to breadth than in <A. spzmosws, and the
3"

12 CRUSTACEA MALACOSTRACA., II.

lateral margins of the four posterior segments show considerable difference from. A. sfimosus, as in
A. vicinus the anterior lateral process of each of these segments is much broader at the base, and this
proximal part has a short, triangular protuberance both in front of and behind the main part of the
process; furthermore the angle in front of the basal joint of each leg is produced into a small, acute
protuberance. The ventral surface of the segments with acute processes as in A. spimosus. — Second
pair of legs (fig.1c) with a strong spine both from the anterior (upper) and the lower (posterior) angle
of fourth joint, with a spine from the upper angle and two spines on the lower margin of fifth joint,
while the sixth joint has two spines on the upper and five on the lower margin; fifth joint as long
as the sixth and a little shorter than the fourth, while in A. sfzmosus the fifth joint is considerably
shorter in proportion to the fourth.

Abdomen scarcely as long as the sum of the three posterior thoracic segments plus half of
the fourth. The lateral processes of the five anterior segments somewhat long but distinctly shorter
than in A. sfzmosus, the short terminal part of each process is suddenly slender. Sixth segment as
long as the three preceding segments and half of the second segment combined, a little more than
two and a half times as long as broad at the middle; the major anterior part of each lateral margin
with six very feeble protuberances, each bearing a conspicuous seta. (Uropods lost excepting their
basal joint.)

Length of the single immature female 6.3 mm.

Remarks. Among the characters enumerated in the description the shape of the eye-lobes,
the processes on the lateral margins of the four posterior thoracic segments and the relative length
of some of the joints in the chelipeds and second pair of legs are most easily observed.

Occurrence. Only taken by the “Thor” at the following locality.

South of Iceland: Lat. 62°57'N., Long. 19°58’ W., 505 fm.; 1 spec.

3. Apseudes tenuis n. sp.
(PL I, figs. 2a—2e).

Subadult Female. The eye-lobes are strongly produced and acute (fig. 2a), almost as much
as in A. vicinus. The lateral process of the head shaped nearly as the eye-lobe; the lateral margin
behind the last-named process considerably convex. The upper surface of the carapace with the trans-
verse furrow very distinct, long.

The antennule more slender than in the preceding species; first peduncular joint more than
four times as long as the second and with the proximal half of the inner margin distinctly serrate;
the inner flagellum to-jointed, more than two-thirds as long as the outer which is 13-jointed. — An-
tenne (fig.2a) with the flagellum 9-jointed and the squama not reaching the end of the penultimate
joint of the flagellar peduncle.

Chelipeds (fig. 2c) considerably more slender than in A. vczmus but conspicuously stronger than
in the two following species. Basal joint on the posterior margin with some minute spiniform sete
on the proximal part and somewhat before its end a very protruding angle bearing a strong spine,
while the anterior margin is furnished with some sete; the ischium has two spines near the end of

the lower margin; the carpus slender with the lower margin unarmed and more than half as long

CRUSTACEA MALACOSTRACA. II. 13

again as the lower margin of the ischium. The chela almost four times as long as broad, with the
posterior margin slightly concave; the movable finger half as long again as the front margin of the hand.

Thoracic segments (figs.2a and 2b) a little more slender than in A. vicinus; second segment
as long as the third. Five posterior segments with their anterior lateral processes in the main shaped
as in A. vicinus, excepting that their distal part is more slender and generally more produced; a lateral,
sharp, triangular protuberance in front of the insertion of the legs on the four posterior segments. —
Second pair of legs (fig. 2d) a little more slender than in A. vicinus; fifth joint slightly longer than
the sixth and as long as the fourth; second joint with a strong spine on the distal lower angle;
fourth joint with a long spine both on the upper and the lower distal angle; fifth joint with a term-
inal upper spine and two strong and distant spines on the lower margin; sixth joint twice as long as
broad; with two spines above and six below; seventh joint with a minute tooth below at the middle.
Seventh pair of legs (fig. 2e) with second joint nearly five times as long as broad; the following joints
are rather slender; sixth joint twice as long as the seventh which is nearly as long as the claw.

Abdomen (fig. 2b) differs somewhat from that in A. vicinus. The lateral processes of the five
anterior segments are long, distally more slender and directed more obliquely backwards than in that
species. Sixth segment a little less than the combined length of second to fifth segment, scarcely
less than three times as long as broad at the middle and with six pairs of lateral sete originating
from minute tubercles. — (Uropods lost).

Length of the largest specimen, a female with small marsupial lamelle, 10 mm.

Remarks, This species is intermediate between the two preceding more robust forms,
A. spinosus and A. vicinus, and the two following very slender species. It is more similar to the latter
forms by the slender chelz, but differs strongly from these and is rather allied to the two first-named
species by the long and strong lateral processes on the abdomen, the serrate proximal half of the
inner margin of first antennular joint, etc.

Occurrence. The “Ingolf’ has taken this species at two deep-sea stations:
Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 21/, spec.
Denmark Strait: St. 11: Lat. 64°34’N., Long. 31°12’ W., 1300 fm., temp. 1.6°; 2 badly preserved spec.

4. Apseudes gracilis Norm. & Stebb.
(PI. I, figs. 3a—3d.)
1886. Afseudes gracilis Norman & Stebbing, Transact. Zool. Soc. London, Vol. XII, Pt. IV, p.g5, Pl. XX.

Subadult Female. As it disagrees with the description and figures of the English authors
in some particulars, the more essential features may be mentioned.

The eye-lobes (fig. 3a) have the outer distal angle produced in a thin, moderately short process
directed nearly forwards. The lateral processes somewhat small, but otherwise shaped and directed
about as the eye-lobes. The surface of the carapace has no transverse furrow.

Antennulz (fig. 3a) somewhat short; the first joint somewhat short, about two and a half
times as long as the second, without serration on the inner margin; the outer flagellum 13-jointed, a

little shorter than the sum of the two proximal peduncular joints and four times as long as the short,

14 CRUSTACEA MALACOSTRACA., II.

3-jointed inner flagellum. — Antennze with the squama conspicuously shorter than the penultimate
joint of the flagellar peduncle; the flagellum 8-jointed.

Chelipeds (fig.3 b) agreeing with the figure of Norman & Stebbing, thus rather slender and
without any spine or tooth on the posterior or lower margin of the joints. Basal joint not fully four
times as long as broad; lower margin of the carpus half as long again as that of the ischium. Chela
almost three and a half times as long as broad, with the posterior margin somewhat concave; movable
finger conspicuously more than half as long again as the front margin of the hand and considerably
overreaching the fixed finger, which has the major part of the distal half of its incisive margin finely
serrate (fig. 3c} and a number of sete inserted on the outer side along the serration.

Second thoracic segment, seen from above (fig.3a), has the first joint of its legs triangular
with the front margin even sloping a little backwards and the outer angle produced a little forwards; third
segment with the outer angle acute and produced slightly forwards. The four posterior segments more
slender than in A. venus; their lateral process proportionately somewhat small with the terminal part thin
and no protruding proximal angle in front or behind; each segment furthermore with a small or rather
small process on the ventral surface. -- Second pair of legs (fig. 3d) somewhat slender; second joint without
any spine at the posterior distal angle; fourth joint even slightly longer than the two following joints
combined, without any spine above or below at the end, but with a number of sete on the upper part
of the outer side and along the distal half of the lower margin; fifth joint slightly shorter than the
sixth and even slightly broader than long, with a terminal upper spine and two spines on the lower
margin; sixth joint distinctly less broad than the fifth, not much longer than broad, with two distal
spines above and eight spines along the lower margin; seventh joint with two denticulations below. —
(Seventh pair of legs lost in the specimen).

Abdomen about as long as the four posterior thoracic segments combined, slender. Five anterior
segments not fully as slender but otherwise shaped nearly as in the following species, thus with the
processes from the postero-lateral angles thin and very short, but without processes below. Sixth
segment about as long as the sum of the four preceding segments, not fully four times as long as broad,
without minute lateral tubercles or setae. — (Uropods lost).

Length of the specimen described, a female with the marsupial lamelle very small, 13 mm.

Remarks. The subadult specimen agrees with the description of Norman & Stebbing in
some important characters: the antennulz without serration on the first joint and a very short,
3-jointed inner flagellum (according to the text of the English authors this flagellum is 4-jointed,
but the figure has only 3 joints), the antennal squama short, the general shape of the chelipeds with
sete on the fixed finger and no spines on any joint, finally the shape and armature of the joints of
seconds legs excepting that the lower margin of sixth joint has only 8 spines instead of 10. But it
differs in several features: the processes of the cephalothorax and thoracic segments are much smaller
than according to the English figures, the abdomen has no processes below and no tubercles on the last
segment, the movable finger of the chelz is longer than the fixed, finally some further particulars to
be found by a comparison of my text with the description of Norman & Stebbing. I am, however,
apt to think that my immature specimen is only a kind of variety of A. gracilis, not a separate species, and

especially the shape and armature of the joints of second pair of legs bear strong witness for this view.

CRUSTACEA MALACOSTRACA. II. 15

Together with the specimen described a very young specimen, measuring only 5.7 mm. and
with seventh pair of thoracic legs not developed, was taken. It shows several peculiarities due to
its very young age, and among these one may be pointed out, viz. that the lower margin of the sixth
joint of second legs has only 5 spines; besides it has a spine at the lower distal angle of fourth joint
of the same legs, but this feature may be interpreted as variation.

Occurrence: The “Ingolf” has captured this species at a single station.

Denmark Strait: St. 10: Lat. 64° 24’ N., Long. 28°50’ W., 788 fm., temp. 3.5°; 1 subadult and 1 very

young specimen.

Besides the “Valorous” took the species at the following place.

South of Davis Strait: Lat. 59°10’ N., Long. 50° 26’ W., 1750 fm.

Distribution. According to the English authors quoted this species was taken by the
“Valorous” at two stations situated considerably South of the Denmark Strait, viz: Lat. 56°1r1'N.,

Long. 37° 41' W., 1450fm., and Lat. 55°10’ N., Long. 25°58’ W., 1785 fm.

5. Apseudes gracillimus un. sp.
(Pl. I, figs. 4a—4e).

Subadult Female. Body and appendages still more slender than in A. gracilis. — Cephalo-
thorax nearly as in that species, but the eye-lobes more produced. The carapace without transverse
furrow.

The antennule (fig. 4a) as long as the carapace and the two anterior free segments combined;
first joint slender, about three times as long as the second, without serration on the inner margin.
Outer flagellum 17-jointed, about as long as the peduncle and more than two and a half times as
long as the 4-jointed flagellum. — The antennze almost as long as the antennular peduncles; flagellum
8-jointed; the squama reaches beyond the end of the penultimate joint of the flagellar peduncle.

The chelipeds very slender (fig. 4c) and their joints without spines or serration on the lower
(posterior) margin. Second joint is considerably curved, long, only a little shorter than the carpus,
five times as long as broad; carpus with the lower margin only somewhat less than twice as long
as that of the ischium. Chela four times as long as broad, with the posterior margin very concave;
the movable finger twice as long as the front margin of the hand and considerably longer than the
fixed finger, which has about 4 sete along the distal half of its incisive margin but no serration or
setigerous area.

Second thoracic segment (fig. 4a) has the first joint of the legs triangular with the front
margin nearly transverse and only the terminal angle produced slightly forwards as an acute denticle.
The four posterior segments have the lateral processes considerably produced, distally slender, acute,
and no produced angles from their proximal part;-the processes on the lower surface of the segments
conspicuous or even rather long. — Second pair of legs (fig. 4d) slender, second joint with a spine on
the lower distal angle; fourth joint conspicuously longer than the sum of the two following joints
and with a spine on the lower distal angle; fifth joint about half as long again as broad, slightly

longer than the sixth, with a terminal spine above and two spines on the lower margin; sixth joint

16 CRUSTACEA MALACOSTRACA. IT.

in the largest specimen with 7, in somewhat smaller specimens with 6 spines on the lower margin
and 2 on the upper; seventh joint with three denticulations below. — Seventh pair of legs (fig. 4e)
very slender; second joint about five and a half times as long as broad; sixth joint has on the distal
half of the inner margin a row of small spines; seventh joint even slightly longer than the sixth;
the claw more than two-thirds as long as seventh joint.

Abdomen (fig.4b) not quite as long as the sum of the four posterior thoracic segments, very
slender. The five anterior segments with conspicuous, slender processes below, and the processes from
the postero-lateral angles very short and slender. Sixth segment as long as the three preceding
segments combined, even a little more than four times as long as broad at the middle, without
tubercles and lateral setz.

Length of the largest specimens, with the marsupial lamellee very small, 14 mm.

Remarks. This species differs from <A. gracilis Norm. & Stebb. in several features of more
or less importance. But some characters, viz. the considerably longer inner flagellum of the antennule,
the extreme slenderness of the chelipeds, no serration or setigerous area on the fixed finger of the
chela, finally the oblong fifth joint of second pair of legs show, according to my judgment, that the
form must be considered a separate species.

Occurrence. Only taken by the “Thor” at the following locality.

South of Iceland: Lat. 62°57'N., Long. 19° 58’ W., 505 fm.; 13 specimens, all mutilated or in

fragments.

Sphyrapus Norman, M.S.; G. O. Sars.

Five species have been established, three of which are represented in our material.

6. Sphyrapus anomalus G. O. Sars.
1869. <Apseudes anomalus G. O. Sars, Nyt Mag. for Naturv. B. XVI, p. 439.

1881. Sphyrapus — — , Arch. for Math. og Naturv. B. 7, p. 19.

1886. — _— Norman & Stebbing, Trans. Zool. Soc. London, Vol. XII, Pt. IV, p. tor,
Pl. XXI, fig. I.

! 1896. — — G. O. Sars, Account Crust. Norway, Vol. II, p. 9; Pls. ITI—IV.

This species, which has been excellently figured and described by G. O. Sars, is closely allied
to the next form, .S. serratus G. O. S. The most conspicuous and perhaps also the most valuable
difference between them is the shape of the “epimera” of the five anterior abdominal segments; in .S.
serratus these epimera are, seen from above, very outstanding, obliquely triangular, acute but not
acuminate, constituting a real saw; in .S. anomalus they were described by Sars as “not at all pro-
duced” and drawn as scarcely or not visible from above, which agrees well with their shape in the
males, but often not completely with their shape in the females. In the female from “Ingolf’ St. 4
the epimera are visible from above, but much smaller than in S. serratus, with the freely outstanding
part rather narrow, acuminate and acute, and in several other females the epimera, seen obliquely
from above and somewhat from the side, are @ little produced, acute, but directed mainly downwards.

In all specimens of .S. anomalus the fifth joint of second pair of legs has only two strong spines on

CRUSTACEA MALACOSTRACA. II. 17

the distal part of its lower margin, while all adult females of .S. serratus have three such spines (in
a single specimen only two spines on one leg and three on the other); furthermore the basal joint of
the antennulz is a little broader and shorter in S. axomalus than in S. serratus.

Occurrefnce. The “Ingolf” has taken this species at eight stations.

Davis Strait: St. 32: Lat. 66° 35’N., Long. 56° 38’ W., 318 fm., temp. 3.9°; 2 spec.
— — St. 28: Lat. 65°14’ N., Long. 55° 42’ W., 420 fm., temp. 3.5°; 2 spec.
a — St. 25: Lat. 63° 30’ N., Long. 54° 25’ W., 582 fm., temp. 3.3°; large num-

ber of specimens.

West of Iceland: St. 8: Lat. 63° 56'N., Long. 24° 4o’ W., 136 fm., temp. 6.0°; 2 spec.

South-West of Iceland: St. 85: Lat. 63° a1'N., Long. 25° 21’ W., 170 fm.; 3 spec.

East of Iceland: . St. 4: Lat. 64°07'N., Long. 11° 12’ W., 237 fm., temp. 2.5°; 1 spec.
North of Iceland: St. 126: Lat. 67° 19’ N., Long. 15°52’ W., 293 fm., temp. + 0.5°; 10 spec.

=. St. 124: Lat. 67° go’ N., Long. 15° 4o’ W., 495 fm., temp. + 0.6°; 1 young.
Furthermore the species has been taken at East Greenland by two Danish expeditions.
Cape Dalton: Lat. 69° 24.6'N., ab. Long. 23° 30’ W., 9—11 fm., Il¢ Amdrup Exp.; large number
of specimens.
Lat. 69° 25’ N., Long. 20° 1 W., 167 fm., large stones and clay, Ryder Exp.; 1 spec.
Hurry Inlet: Lat. 70° 50’ N., Long. 22° 31’ W., 10 fm., II¢ Amdrup Exp.; 1 specimen.
Lat. 72° 40'N., Long. 20° 10! W., 100 fm., Ryder Exp.; 1 spec.

Distribution. .S. anomalus has been captured by Cand. mag. Ad. Jensen (“Michael Sars”) at
two places North-East and East of the Shetlands Islands: Lat. 61° 40’ N., Long. 3° 11'E., 220 fm.; 1
spec., and Lat. 60°57'N., Long. 3°42’ E., 190 fm., temp. 6.1°; 1 spec. The “Thor” has captured it in the
Skager Rak in depths from 280 to 350 fm. Sars has taken it “along the whole Norwegian coast from
the Christiania Fjord to Vads6”, in depths “from 100 to 400 fathoms”. Finally it is known from the
Kara Sea, 50 fm. (Hansen) and from the places South of Novaia Zemlia, between Lat. 70° 20’ and
70° 40’ N., Long. 54° 08’ and 56° 35’ East, 61 and 90 meters (Stappers).

According to all these statements S. axomalus has been taken a single time in 50 fathoms in
the very cold Kara Sea, three times in still lesser depths South of Novaia Zemlia and at numerous
places in depths between 100 and 582 fathoms both in the cold area and especially at localities with

the temperature somewhat or even considerably above the zero.

7. Sphyrapus serratus G. O. Sars.

1881. Sphyrapus serratus G. O. Sars, Arch. for Math. og Naturv. B. 7, p. 20.
! 1885. _ — —_ Norske Nordhavs-Exp. Crust. I, p. 66, Pl. XXI.
The differences between this species and .S. anomalus have been pointed out above.
Occurrence. The “Ingolf? has captured .S. serratus at five stations, all in the cold deep-
sea area.
North of Iceland: St. 124: Lat. 67° 40’ N., Long. 15° 40’ W., 495 fm., temp. + 0.6°; I spec.
ee = St. 125: Lat. 68° 08'N., Long. 16° 02’ W., 729 fm., temp. + 0.8°; I spec.

The Ingolf-Expedition. III. 3. 3

18 CRUSTACEA MALACOSTRACA. II.

South of Jan Mayen: St. 119: Lat. 67° 53'N., Long. 10° 19’ W., ro1o fm., temp. + 1,0°; 4 spec.
—_— - — St. 117: Lat. 69° 13’ N., Long. 8° 23’ W., 1003 fm., temp. + 1,0°; 4 spec.
— - — St. 113: Lat. 69° 31’ N., Long. 7°06’ W., 1309 fm., temp. + 1,0°; 4 spec.
Besides this species has been taken by the Norwegian North-Atlantic Expedition at two sta-
tions between Norway and Iceland in 1163 fm. and 1215 fm. and the temperatures were + 1.1° and
+ 1.2°; besides it was taken West of Spitzbergen: Lat. 77°58’N., Long. 5° 10'E., 1333 fm., temp.
+ 1.4° (Sars).
S. serratus has thus been captured in all nine times, and always in temperatures somewhat or
considerably below zero.

8. Sphyrapus tudes Norm. & Stebb.").
1886. Sphyrapus tudes Norman & Stebbing, Trans. Zool. Soc. London, Vol. XII, Pt. IV, p. 99; Pl.
XXII, fig. 1.

This very characteristic species has been well described and figured by the English authors.

Occurrence. S./udes has not been taken by the “Ingolf” but at two localities by the “Thor”.

South-West of the Feroes: Lat. 61° 15’ N., Long. 9° 35’ W., 475 fm.; 26 spec.

_— - - — Lat. 61° 7'N., Long. 9° 30’ W., 440 fm.; 22 spec.

Distribution. This species was taken by the “Porcupine” South of Rockall: Lat. 56° 13' N.,

Long. 14° 18’ W., 420 fm. (Norman & Stebbing).

Fam. Il. Tanaide.

This family comprises eighteen genera hitherto established; twelve of these are represented in
the “Ingolf” material, and three new genera are established.

Neotanais Beddard.
(Alaotanais Norm. & Stebb.).
This genus, which contains some of the largest forms of the family, comprises five species al-
ready established. The “Ingolf” collection contains two species, one of which is new, but a third

species is enumerated below because it was taken by an English expedition near the entrance of the
Davis Strait.

9. Neotanais serratispinosus Norm. & Stebb.
(Pl. I, figs. 6a—6b; Pl. II, figs. 1a—trc.).
1886. Alaotanais serratispinosus Norman & Stebbing, Trans. Zool. Soc. London, Vol. XII, Pt. IV, p.
111; Pl. XXIII, fig. 1; Pl. XXIV, fig. 1.
1) The fourth species of this genus, Sphyrapus malleolus Norm. & Stebb., can scarcely be included in this report, as
it has not been taken by any Danish expedition, and the mst northern among the localities enumerated by the English

authors is at Lat. 57° 11’ N., Long. 37° 41’ W., thus South-East of Cape Farewell, but about 12 geographical miles South of
the area dealt with in the present paper.

CRUSTACEA MALACOSTRACA. II. 19

Norman & Stebbing have published a good description and a number of figures of this cha-
racteristic species. The single adult specimen at hand, a female with the marsupium fully developed,
measures 6.7™™ in length, and is somewhat smaller than the largest specimen seen by the English
authors, as they stated it to be 85™™ long. My specimens agree well with their description, but I
think it useful to give some analytical figures with some remarks.

The chelz (fig. 6a) are somewhat longer than the carpus, a little more than twice as long as
broad, with the posterior margin considerably sinuate, as almost its proximal half is conspicuously
concave, the distal half rather convex. The movable finger is somewhat shorter than the front margin
of the hand; its incisive margin is armed with six low to extremely low teeth (fig. 6b) increasing much
in breadth from the proximal to the penultimate tooth and decreasing much in height from the first
to the last tooth; each tooth has its distal end produced into a minute, oblong-triangular, acute tip.
The fixed finger has its terminal part bent considerably and shaped as a thick, somewhat spiniform
process with the margins glabrous, while the remaining long part of the incisive margin has almost
its proximal half furnished with a close row of numerous very small teeth and the distal portion with
five large, very broad and proportionately somewhat low, obtuse, brownish teeth.

Fig. ta represents the terminal part of third left thoracic leg from behind; some nine long,
glabrous and strong sete originate in an oblique row from the margin of sixth joint, which above
terminates in three very thick, serrate spines; seventh joint, seen in the intervals between the setze,
is distally slender and three times as long as the straight claw. — Fig. 1b represents the terminal
part of sixth left leg from behind, and fig. rc the corresponding part of seventh left leg from above;
the last-named part has a transverse row of spines above the base of the long sete at the end of
sixth joint; in both legs the seventh joint is distally a little flattened and widened towards the rounded
end which expands as a roof beyond the insertion of the claw; the distal part of seventh joint is
closely serrate along the terminal margin and the most distal portion of the lateral margins, and from
this serration to near the middle of the joint each lateral margin has a very close row of minute,
very slender spines; the claw is half or more than half as long as seventh joint.

Occurrence. This fine species was taken by the “Ingolf? at a single station.

South of Greenland: St. 22: Lat. 58° 10’ N., Long. 48° 25' W., 1845 fm., temp. 1.4°; 3 spec.

Distribution. Norman & Stebbing examined specimens from a station South of Greenland
at Lat. 56° 11’ N., Long. 37° 41' W., 1450 fm., and from two localities respectively North-West of Ireland
and West of North Ireland, 1360 and 1380 fm.

10. Neotanais hastiger Norm. & Stebb.
1886. Alaotanais hastiger Norman & Stebbing, Trans. Zool. Soc. London, Vol. XII, Pt. IV, p. 1103;
Pl. XXIII, fig. 2.
Occurrence. This species, which has not been gathered by any Danish expedition and has
never been seen by me, is enumerated here because the single specimen hitherto known has been taken
by the “Valorous” at a locality not far from the “Ingolf’ St. 38 and between this station and Cape

Farewell, viz. at Lat. 59° 10’ N., Long. 50° 25’ W., 1750 fm.
= bg

20 CRUSTACEA MALACOSTRACA. IL

11. Neotanais giganteus n. sp.
(Pl. I, figs. 2a—2h.)

Adult Male. Carapace nearly as long as the three following segments combined, seen from
above peculiarly shaped (fig. 2a), as scarcely its front half has the lateral margins feebly convex and
is only a little longer than broad, while the major posterior part is laterally considerably expanded,
but the postero-lateral area of this part is subquadrangular, well marked off by a suture and must be
considered the coxal joint of the chelipeds. A portion of each lateral margin somewhat behind the
front angle is furnished with a close row of outstanding, stiff sete (fig. 2b).

The ocular plate is well marked off (fig. 2), nearly ovate, with the end subacute and without
any vestige of visual elements. — The antennule (fig. 2b) are somewhat longer than the carapace,
7-jointed; the first joint is very long, as long as the other joints combined, seen from above with the
inner margin straight, the major proximal part of the outer margin distinctly concave, but the distal
part of this margin somewhat convex and bearing a close longitudinal row of horizontal, stiff setee.
Second joint almost as thick, but somewhat less than half as long, as the first, with a shorter row of
stiff, horizontal setee on the outer margin. Third joint is short and rather thick; fourth joint is some-
what shorter than the second, tapers much towards the end and has on the outer side a long row of
long sensory hairs; fifth and sixth joints, and especially the last-named, are short, and seventh joint is
extremely short. — The antenne (fig. 2c) 9-jointed; second, fourth and fifth joints long; third joint a
little longer than deep; sixth joint a little shorter and considerably thinner than the fifth; seventh and
especially eighth joint somewhat shorter and thinner than the sixth, and ninth joint short and very thin.

The chelipeds (fig. 2d) are robust. The coxal joint is mentioned above. The basal joint is
moderately short but extremely thick, its whole lower side being produced downwards as a long, thick.
and rounded protuberance. The carpus is long, almost three times as long as deep, and the proximal
third of its lower margin is deeply concave. The chela is a little longer than the carpus, two and a
half times as long as broad; the movable finger, which is much curved near the middle and somewhat
shorter than the strongly convex anterior margin of the hand, has almost the proximal half of its
incisive margin serrate and a strong, triangular tooth considerably beyond the middle. The fixed
finger has on the incisive margin near its middle a long, straight, subcylindrical, distally rounded pro-
cess, and near the base a broad protuberance with two small incisions: The fingers cross each other
greatly, while a large interval is left between their major proximal part.

The thoracic segments subsimilar in shape, length and breadth (fig. 2a), excepting the seventh
segment which is somewhat shorter; the lateral margins of the segments are very convex. — The
legs are moderately slender and somewhat long, all subsimilar, the only exception being that the real
claw is extremely short on the anterior pairs (fig. 2), a little longer on the posterior pairs (fig. 2 g).
Third joint is extremely short, fifth joint a little longer than the fourth, a little shorter than the sixth
(fig. 2), and the distal half of its lower side is furnished with a number of sete; sixth joint has the
distal half of the lower margin and the end set with a good number of sete; seventh joint with claw
much shorter than sixth joint.

The abdomen as long as the sum of the fouf preceding segments; its four anterior segments
are broader than the thorax; the pleopods are strongly developed. Sixth segment not quite as long

CRUSTACEA MALACOSTRACA. II. 21

as the two preceding segments combined, somewhat narrower than fifth segment, and posteriorly
emarginate. — Uropods (figs. 2a and 2h) slightly shorter than the abdomen; peduncle about two and
a half times as long as broad; endopod very long with thirteen joints, the first joint conspicuously
thicker than the second and third and as long as these two combined; exopod very small, two-jointed,
with the proximal joint shorter than the distal.

Length 20™™,

Remarks. Though new species of this family as a rule ought not to be founded on adult
males, I venture to establish a new species on the specimen described, because it is not only charac-
teristic but very much larger than any specimen of Tanaidz hitherto captured. The animal when
hauled up from the sea was quite white.

Occurrence. The “Ingolf® has taken this species at a single station.

Davis Strait: St. 36: Lat. 61° 50'N., Long. 56° 21’ W., 1435 fm., temp. 1.5°; 1 spec.

Heterotanais G.0.S.
Of this genus nine species have been established. The material at hand contains only a single

probably new species.

12. Heterotanais groenlandicus n. sp.
(Pl. I, figs. 5a—5¢g.)
1887. Heterotanais limicola H. J. Hansen, Vidensk. Medd. Naturh. Forening i Kobenhavn for 1887,
p- 178 (Probably not A. (Paratanazy) limicola Harger).
Female. The body (fig. 5a) about six times as long as broad. — Carapace only a little
longer than the two anterior thoracic segments combined, a little longer than broad, anteriorly not
fully half as broad as somewhat before the posterior margin (fig. 5 b).

The eye-lobes are considerably produced, distally not angular but rounded (fig. 5); the eyes”
are moderately large, black, but the black pigment renders it impossible to count the ocelli, a couple
of which are seen at the hind margin of the black spot. — The antennule (figs. 5a and 5c) are a
little shorter than the carapace, somewhat slender; first joint somewhat longer than the two others
combined, almost four times as long as deep; third joint about twice as long as the second. — An-
tennze somewhat slender; fourth joint (formed by fusion of fourth and fifth joints) only as long as the
two preceding joints combined. , :

; The chelipeds (fig. 5c) are somewhat robust; the carpus is almost twice as long as deep. The
chela is somewhat longer than the carpus and somewhat more than twice as long as broad; the
movable finger is much shorter than the hand; the fixed finger (fig. 5d) is somewhat expanded on
the incisive side with about three low protuberances and near the end rather broad and distally rect-
angular, while the very short apical part of the finger is slender and marked off from the inner
expansion.

Second pair of legs (fig. 5) with a very long seta from the upper distal angle of fifth joint;
sixth joint about as long as fifth and fourth joints combined and/a little shorter than seventh joint
with claw; seventh joint a little shorter than the claw. Third pair of legs (fig. 5e) have the seventh

22 CRUSTACEA MALACOSTRACA. II.

joint and the claw about equal in length and together conspicuously more than half as long as the
sixth joint. Seventh pair of legs (fig. 5f) with the second joint proportionately somewhat slender,
four times as long as broad.

Abdomen scarcely or slightly broader than the thorax. — Uropods a little more than half as
long as the abdomen; the endopod five-jointed (fig. 5g), but sometimes the first joint is divided again
into two joints by a less conspicuous suture, and the relative length of the joints shows considerable
variation; exopod as long as or longer than the first joint of the endopod, two-jointed.

Length of a female with marsupium 2.9 ™.

Remarks. In the above-named paper I had referred specimens of this species to Heterotanais
(Paratanats) limicola Harger, though, as may be seen in the paper, I was well aware that Harger’s
description of the eyes did not agree with my specimens. Harger said that “the eyes are small and
inconspicuous”, while in the specimens seen by me the eyes are of considerable size, black and
consequently very conspicuous, and having examined a large number of species of this family I am
now inclined to think that the difference mentioned is a specific character. Harger’s figures of his
H. limicola, especially that of the cheliped, are too small for forming a judgement of some particulars.
— H. groenlandicus differs in several important features from H. Oerstedii Kr. in which the eye-lobes
are subacute, the third antennular joint not much longer than the second, the carpus and the chela
of the chelipeds considerably thicker and the endopod of the uropods only four-jointed.

Occurrence. The “Ingolf” gathered this species at a single locality.

West coast of Greenland: Mouth of Ameralik Fjord, Godthaab (about at Lat. 64°11' N.), 5—7ofm.,

shells; 25 spec.

The Copenhagen Museum possesses specimens from a few places in West Greenland, viz.
Preven (Lat. 72° 23'N., Long. 55° 23’ W.), 1 spec.; Jakobshavn (Lat. 69°13' N., Long. 51°0' W.), 1 spec.
(brought home by Mag. Traustedt); Godthaab, 10 spec. found between numerous specimens of the
genus dZefofa dredged in “deep water” (probably 40—60 fm.) where the bottom was clothed with

Sertularia.

Distribution. Apart from West Greenland this species has not yet been recorded.

Tanais H. Milne-Edw.

Of this genus seventeen species have been established, but only a single form is known from
our northern area.

13. Tanais Cavolinii H. Milne-Edw. ;
1829. Zanais Cavolinii H. Milne-Edwards, in Audouin and Milne-Edwards: Précis d’Entomologie, I,
Pl. XXIX, fig. 1 (Quoted from Miss Harr. Richardson).
!1842. Zanais tomentosus Kroyer, Nat. Tidsskr. B. IV, p. 183. i
? — — Kroyer, Voy. en Scand. Crust. Pl 27, fig. 2a—q.
1847. _ — Kroyer, Nat. Tidsskr. Ny R., B. II, p. 412.
! 1896. — — G. O. Sars, Account Crust. Norway, Vol. II, p.12, Pl. V.

CRUSTACEA MALACOSTRACA. II. 23

1899. Zanatis Cavolintt A.M.Norman, Ann. Mag. Nat. Hist. Ser. 7, Vol. III, p. 332.
1905. — _ Harr. Richardson, Mon. Isop. North America, Bull. U.S. Nat. Mus. No. 54, p. 8.

The tangled synonymy of this well-known species is found in Norman’s and Miss Richardson’s
papers.

Occurrence. The “Ingolf” secured this species at a single locality.

Feeroes: Trangisvaag, between alge at the shore. Many specimens.

In the paper on the Malacostraca from West Greenland I stated that a specimen with the
label: “Greenland, Kréyer’s effects”, was preserved in the Copenhagen Museum; for this reason I
mentioned the species, but did not number it, as I feared that the statement was not quite certain.
Nevertheless Norman and other authors have on my authority included “Greenland” in the enumeration
of the distribution of the species. But as 7 Cavolinii has not been found at Iceland and has not in
recent time been captured at Greenland I am now nearly sure that the species does not live at the
_ last-named country.

Distribution. This species is known from Mresund (Kréyer), the western coast of Norway
northwards to Lat. 63°20'N. (G. O. Sars), Scotland northwards ab. to Lat. 56'/,N. (Norman), Eng-
land and Ireland (several authors), the Channel Islands (various authors), West France (Chevreux),
many places in the western half of the Mediterranean (several authors), Azores (Barrois); finally
Connecticut, Long Island Sound and Castle Harbour, Bermudas (H. Richardson). It lives always in
quite shallow water, from the beach down to a few fathoms.

Pseudotanais G.0.S.

Of this genus five valid species have been established; four of these are boreal or arctic, while
the fifth species is only known from the Mediterranean. The “Ingolf’ captured six species, three of
which are new,

This genus differs materially from all other genera by having fifth and sixth thoracic segments
very long as compared with the fourth segment and especially with third and second segments. It
is placed here because in some other features it is intermediate between Zamnazs and Paratanais—
Typhlotanats, It agrees with Zanais and differs from the other genera in possessing only a single
pair of marsupial lamelle; as to antennule, antennze, uropods and development of second pair of legs
as compared with the following pair it agrees on the whole with Paratanats— Typhilotanais; as to the
mouth-parts — mandibles and maxillipeds — it differs strongly from the genera named and is more

related to Leptognathia, though showing peculiarities not found in the last-named genus.

14. Pseudotanais forcipatus Lilljeborg.
(Pl. II, figs. 3a—3 e).
1864. TZanais forcipatus Lilljeborg, Bidrag till kannedomen om de inom Sverige och Norrige
férek. Crust. of .... Tanaidernas familj., p.16 (Female and Male).
11897. Pseudotanais forcipatus G.O,.Sars, Account Crust. Norw., Vol. II, p. 40; Pl. XVII, fig.1 (Female
and subadult Male).

24 CRUSTACEA MALACOSTRACA, II.

!1907. Pseudotanats forcipatus Vanhdéffen, Zool. Jahrbiicher, Abth. fiir Syst., Bd. XXV, p. 511; Taf. 20,
fig. ro—12 (Adult Male).

Female. Sars has published a good description with numerous figures of this sex. To his
description may be added that the front margin of the head, seen from above, is shaped as in
P. Lilijeborgit (comp. fig.5a), thus nearly transverse, feebly convex at the middle, not emarginate at
the antennule, and the antero-lateral angles not produced. me

The female is readily distinguished from the other northern species, excepting P. adyssz n. sp.,
by the strongly forcipate chele; from P. abyssi it is separated by having no pleopods, the uropods
much shorter, the antennule and the walking legs shorter and thicker, etc.

Subadult Male. It has been figured and mentioned by Sars, who erroneously considered it
the adult male. It agrees with the female in the shape of the chele, the antennule, the distal joints
of the thoracic legs, etc., but it differs in three features: fourth and fifth thoracic segments shorter,
but abdomen proportionately longer and thicker than in the female, and the pleopods well developed
with long sete. — In younger male specimens the thoracic and abdominal segments are more similar
to those of the female, while the pleopods are smaller with the sete short.

Adult Male. Almost fifty years ago Lilljeborg published a brief description in the Swedish
language of this sex, but did not figure it, and some five years ago Vanh6ffen (l.c.) pointed out the
main differences between female and adult male, with three analytical figures of male appendages. A’
more full description may be given here.

The anterior end of the head about half as broad as the carapace (fig. 3a); the front margin
is deeply emarginate at the base of each antennula (fig. 3c) and the antero-lateral angles considerably
produced with the end blunt; in a lateral view (fig.3b) the head is produced forwards covering the
base of the outer side of the antennula as a rounded plate.

The antennule are seven-jointed (figs. 3b and 3c); the two proximal joints are yery thick,
subequal in length and together a little longer than the five others combined; third joint broad and
a little longer than the two next joints combined; fourth joint very short, with a tuft of sensory
hairs on the lower distal angle; the four distal joints increase considerably in length and decrease in
thickness from the fourth to the seventh; fifth and sixth joints with some sensory hairs at the outer
distal angle; seventh joint considerably longer than the sixth.

The chelee (fig. 3b) are a little more than twice as long as broad and differ much from those of
the female; the fixed finger at the base twice as broad as the movable, but the major distal part of
its incisive margin is so concave, that a conspicuous interval is seen between the fingers when their
terminal parts cross each other. The movable finger is evenly curved, somewhat longer than the
front margin of the hand; the inner surface of the hand has above the insertion of the movable finger
a transverse row of about nine peculiar sete.

Fifth thoracic segment (fig. 3a) a little shorter than the two preceding segments combined and
as long as sixth segment. The thoracic legs are conspicuously more slender than in the female.
Second pair have the seventh joint with claw“longer than sixth joint; third and fourth pairs with the
spurs short and simple, while their seventh joint plus claw is only a little shorter than sixth
joint; on the three posterior pairs (fig. 3d) seventh joint together with its claw is much longer

CRUSTACEA MALACOSTRACA. II. 25

than in the female, about as long as the sixth joint, and the claw is conspicuously longer than
seventh joint.

Abdomen much larger in proportion to the thorax than in the female, as long as the sum of
the four posterior thoracic segments; sixth segment (fig. 3) produced considerably backwards, much
longer than in the female and with the hind margin deeply emarginate, while the postero-lateral
angles are scarcely rounded. — Pleopods about as in the female P. adyssz, with moderately narrow
rami and the sete very long. — Uropods (fig. 3e) in the main as in the female, but a little more
slender, and one of the terminal setze of the endopod extremely long.

Length of two males 1.25 and 1.40 mm.

Occurrence. The “Ingolf” has taken this species at two localities.

West Greenland: Inner end of Ameralik Fjord, Godthaab, muddy bottom; 43 specimens, 2 of

; which are adult males.
~ North of Iceland: St. 128: Lat. 66° 50’ N., Long. 20° 2’ W., 194 fm., temp. 0.6°; 4 spec.

P. forcipatus has besides been captured by other collectors at the following five localities within
our area.

West Greenland: Karajok Fjord, ab. Lat. 70° 20'N.; many spec. Vanhdffen.

East Iceland: Faskrud Fjord, 20—so fm.; 1 spec. Mag. sc. R. Horring.

. East Greenland: Cape Dalton, Lat. 69° 24’ N., g—11 fm.; 5 spec. (2 and 4). II¢ Amdrup Exp.
- — Turner Sound, Lat. 69° 44'N., 3 fm.; 8 spec. IJ¢ Amdrup Exp.
- — Denmark Isl., Lat. 70° 27’ N., Long. 26° 12’ W., 10 fm., clay; 2 spec. Ryder Exp.
- _ - - several spec. Ryder Exp.

Distribution. This species has been established on specimens taken off Bohuslan in 507—60
and 120—130fm. In the Danish seas it has been taken four times, viz. two times in the south-western
Kattegat, 13 and 15 fm., and two times in Skager Rak, in 70 and 125 fm. (H. J. Hansen). According
to Sars it has been found along the whole Norwegian coast northwards about to Lat. 70° N. Furthermore
it was captured in Klosterelv Fjord, East Finmark, close upon the frontiers of Russia (A. M. Norman),
in the Barents Sea at Lat. 76°26’ N., Long. 60°55’ N., vertical pelagic haul from 30 to o meter (Stappers)
and at Northbrook Island, Franz Joseph Land, 10 fm. (Th. Scott). Finally it is known from some
localities in the northern Scotland, in 8—1o0 and 50—55 fm. (Th. Scott).

This species is thus boreal and arctic and lives in very moderate depths, from some few

fathoms and down to nearly 200 fathoms.

15. Pseudotanais abyssi n. sp.
(Pl. I, figs. 4a—4i.)

Female. The body of the females with marsupium (fig. 4a) somewhat more than three times
as long as broad; in the immature female it is conspicuously more slender. — Carapace, seen from
above, with the lateral margins considerably convex excepting near the front end and two and a half
times as broad as this front end; the anterior margin feebly concave behind the antennulz, feebly
produced at the middle and at the lateral angles. — Eyes wanting.

The antennule (figs. 4a and 4c) as long as the carapace, the second segment and half of the
The Ingolf-Expedition III. 3, 4

26 CRUSTACEA MALACOSTRACA. IL.

third segment combined, rather slender. First joint, seen from the side, not fully five times as long
as deep, decreasing conspicuously in depth from the base towards the middle and somewhat longer
than the two other joints combined; third joint only a little longer than the second. — Antenne
(fig. 4c) moderately slender; second and third joints without any spine at the distal upper angle;
fourth joint (in reality formed by a fusion of fourth and fifth joints) two and a half times as long as
the penultimate joint. *

Chelipeds (fig. 4d) somewhat slender. Carpus conspicuously longer than the basal joint, two
and a half times as long as deep. Chela much longer than the carpus, nearly two and a half times
as long as broad, with the posterior margin feebly concave; the fixed finger only slightly broader than
the proximal part of the movable and keeping the same breadth from near the base to the middle;
the movable finger is conspicuously longer than the front margin of the hand, moderately slender,
with the major part of its incisive margin almost convex, at the base far from touching the fixed
finger, so that the fingers, when their distal parts are crossed, are very forcipate, leaving a consider-
able triangular interval between their proximal halves.

Fifth thoracic segment (fig. 4b) as long as the sum of the three preceding segments and
scarcely or slightly longer than the sixth segment. — The thoracic legs are slender and somewhat long.
Second pair (fig. 4e) with sixth joint a little shorter than fourth and fifth joints combined (the arti-
culation between these two joints forgotten on the figure) and almost half as long again as seventh
joint with claw, and seventh joint itself is much shorter than the claw. Third pair (fig. 4f) with the
sixth joint not quite half as long again as the fifth and twice as long as seventh joint with claw;
seventh joint and claw equal in length; spur on fifth joint moderately slender, not expanded; con-
siderably less than half as long as sixth joint. Three posterior pairs of legs (fig. 4g) with second
joint long and slender, sixth joint a little longer than the fifth, seventh joint rather short, claw ex-
tremely short; the spur slender and only about as long as the diameter of the joint.

The abdomen somewhat longer than the sum of the two preceding segments (fig. 4a).
Pleopods well developed; their rami with very long sete (fig. 4h). — Uropods somewhat long (fig. 4i);
endopod with the proximal joint a little longer than the distal; exopod slender, reaching a little or
somewhat beyond the end of the first joint of the endopod, and its two very distinct joints subequal
in length. ;

Length of a female with the marsupium half developed 1.17™™.

Remarks. This small species agrees with P. forcifatus in having no eyes and the chelz
strongly forcipate, but it differs from it in several features, especially in possessing well developed
pleopods with long sete, longer uropods, longer and more slender chelipeds and legs. P. abyssi bears
some resemblance to P. oculatus nu. sp. but the latter differs in having distinct ocelli, the chelz con-
spicuously less forcipate, the exopod of the uropods longer and in several particulars in the legs.
From the other northern species of the genus P. aéyssz differs greatly, above all in having the chelez
strongly forcipate. ,

Occurrence. The “Ingolf” secured this species at a single station.

Davis Strait: St. 36: Lat. 61° so’ N., Long. 56° 21' W., 1435 fm., temp. 1.5°; 3 spec. (2 are females

with the marsupium half developed).

CRUSTACEA MALACOSTRACA. II. 27

16. Pseudotanais Lilljeborgii G. O. Sars.
(Pl. II, figs. 5a—5¢.)
1881. Pseudotanais Lilljeborgii G. O. Sars, Arch. for Math. og Naturv. B. 7, p. 48.
! 1897. a Lilljeborgi — Account Crust. Norw., Vol. II, p. 40; Pl. XVII, fig. 2.

Female. Sars has described and figured the female, while he has not seen any immature
or adult male. But his representation of the front end of the head with the eyes is not quite correct.
My fig. 5a represents the outline of the carapace with the right antennula; it is seen that the cara-
pace is about two and a half times as broad as its front margin, which is transverse and a little
convex at the middle. Sars mentioned the eyes and figured them as black spots, but while these
spots frequently are distinct in specimens preserved during some years in spirit, I was unable to find
them in specimens from several of the deeper “Ingolf” stations. Furthermore, internal visual elements
of an ocellus or some two to three ocelli seem sometimes but not always to be distinguishable, but I
have been unable to detect any cornea, so that the eyes must be considered quite rudimentary.

The female is well distinguished from the other species by a combination of characters, among
which the most important may be enumerated. Third antennular joint is only slightly longer than
the second; the chela is from two and a half to three times as long as broad, not forcipate; the legs
are robust, the spurs of third to seventh pairs very broad and short or very short; the pleopods ate
wanting, and the uropods are short, with the two-jointed exopod not quite as long as the proximal
joint of the rather stout endopod. — The length 1.55—2.05™™.

Immature Male. Agrees with the female excepting as to the abdomen, which is stronger
and proportionately somewhat or considerably longer than in that sex; furthermore the pleopods are
less or more developed according to age. In a younger male the pleopods are rather short with their
setee quite short. In a subadult specimen the pleopods are very well developed, conspicuously longer
than the uropods, with their rami very oblong and some of the sete longer than the rami. In the
last-named specimen the third antennular joint is a little thickened below; finally fig. 5 g represents
the distal part of seventh leg, which agrees with that of the female in the following important parti-
culars: the spur (on fifth joint) is very short and broad; the seventh joint, which is somewhat thick,
is only one-third as long as sixth joint; the claw. is thick and short.

Adult Male. Somewhat similar to the male of P. forcipatus, but differs in several particulars.
In the relative length of the thoracic segments as compared with each other and in the strong
development of abdomen it agrees with the male of P. /orcipatus and differs consequently much from
the female.

The front margin of the head (fig. 5 b) between the outer angles of the antennular peduncles
is considerably convex; at the outer base of each antennula the lateral part of the head (fig. 5c) is a
somewhat high, flatly rounded lobe which, seen from above (fig. 5b), is very conspicuous and marked
off by an oblique suture forming the continuation of the median part of the front margin; this antero-
lateral small part of the head is thus above, but not on the side, marked off as an eye-lobe, but a
real eye could not be discovered. — The seven-jointed antennule (figs. 5b and 5¢) are rather similar
to those of the male P. forcipatus, but the two proximal joints are less robust and the seventh joint

not longer than the sixth.
4*

28 CRUSTACEA MALACOSTRACA. II.

The chelz (fig. 5c) are somewhat less than three times as long as broad, with the posterior
margin very moderately concave, shaped in the main as in the female, but the fingers are conspi-
cuously shorter in proportion to the hand; the movable finger is thicker and the fixed finger near
the base less thick than in the male P. forcipatus.

The thoracic legs as in the male P. forcipatus conspicuously more slender than in the female
and as in that species showing other differences, but besides affording specific characters. Second
pair (fig. 5c) with seventh joint plus claw more than half as long again as sixth joint. Third and
fourth pairs with the short spur rather slender, while seventh joint with claw is as long as sixth
joint. Three posterior pairs of legs (figs. 5e and 5 f) with the spur short and rather slender; seventh
joint with claw only a little shorter than sixth joint, and the claw itself only half as long as
seventh joint.

The five anterior abdominal segments, seen from above (fig. 5d), with the lateral margins of
each segment very convex, so that the entire lateral margin of this part of the abdomen has five
deep incisions, while in the male P. /forcifatus this margin shows no such incisions. Sixth segment
posteriorly somewhat produced, but much less than in P. forcipatus, and has at the middle of the
hind margin a somewhat small, angular emargination. — The highly developed pleopods with some
of the sete more than twice as long the rami. — The uropods in the main similar to those in the
female, but the rami a little longer.

Length of the single male 1.8™".

Occurrence. The “Ingolf” has captured this species at seven localities.

West Iceland: St. 86: Lat. 65°03’ N., Long. 23° 47.6’ W., 76 fm.; 1 spec.

East of Iceland: St. 4: Lat. 64°07'N., Long. 11° 12’ W., 237 fm., temp. 2.5°; 3 spec.

- eS St. 58: Lat. 64°25'N., Long. 12°09’ W., 211 fm., temp. 0.8°; 14 spec.

East Iceland: Seydis Fjord, 20—50 fm.; 5 spec.

North of Iceland: St. 128: Lat. 66° 30' N., Long. 20°02’ W., 194 fm., temp. 0-6°; 4 spec.

- - = St. 126: Lat. 67° 19'N., Long. 15° 52’ W., 293 fm., temp. + 0.5°; 5 spec.

Jan Mayen: St. 115: Lat. 70°50’ N., Long. 8° 29' W., 86 fm., temp. 0.1°; 10 spec.

P. Lilijeborgit has besides been taken by other expeditions at six localities situated in very
different parts of our area.

West Greenland: Karajok Fjord, ab. Lat. 70°20’ N.; several spec. Vanhoffen.

East Iceland: Nord Fjord, 40 fm.; 5 spec. Mag. sc. R. Herring.

East Greenland: Angmasivik, at Lat. 65°51’N.; 1 spec. Mag. sc. Kruuse.

- — Cape Dalton, Lat. 69° 24' N., g—11 fm; 2 spec. (? and adult ¢'). Il¢ Amdrup Exp.

- — Denmark Isl, Lat. 70°27’ N., Long. 26°12'W. 4—5 fm., muddy bottom; 1 spec.
Ryder Exp.

. -- _ - 1 spec. Ryder Exp.

Jan Mayen: 55 fm.; 1 spec. II¢ Amdrup Exp.

Distribution. Outside our area hitherto known from Varanger Fjord at Vadso (ab. Lat.
7o°10' N. in East Finmark), “in a depth of 100—120 fathoms” (G. O. Sars); recently it has been taken
in the Barents Sea, Lat. 76° 26’ N., Long. 60°55’ E., vertical pelagic haul from 30 to o meters (Stappers).

CRUSTACEA MALACOSTRACA. II. 29

P. Lilgeborgi is thus more arctic than P. forcipatus; at the very cold places in the northern East
Greenland it was found in quite low water, while in the open sea off Iceland it was most frequently

found in depths from about 200 to near 300 fm.

17. Pseudotanais oculatus n. sp.
(Pl. Il, figs. 6a—6d; Pl. III, figs. ra—1d.)

Female (with the marsupium half developed, and younger specimens). Body four times as
long as broad. —- Carapace, seen from above (fig. 1a), with the lateral margins somewhat convex ex-
cepting near the front end, anteriorly half as broad as somewhat from the hind margin; the front
margin is considerably bent, forming an angle at the middle, and the antero-lateral angle is produced,
but seen from the side (fig. 1c) this produced part is not rounded but angular at the upper base of
the antennae. — The eyes are well developed, rather large, with about seven ocelli, and the cornea of
each ocellus very conspicuous; in recently captured specimens the eyes are black and in a couple of
specimens the dark colour has been preserved during many years.

Antennulz about as long as the carapace plus second and half of the third thoracic segment,
somewhat slender. First joint, seen from the side (fig. 1c), about four times as long as deep and with
the proximal part much deeper than the middle part; this joint is somewhat longer than the two
other joints combined, and third joint is somewhat longer than the second. — Antenne somewhat
robust; second and third joints proportionately long, without any real spine at the distal upper angle;
third joint a little less than half as long as the fourth, which is a little less than twice as long as
the penultimate joint.

Chelipeds (figs. 1b and 6a) moderately slender. Carpus somewhat less than twice as long as
deep. Chela three times as long as broad (fig. 6a), with the posterior margin considerably concave;
fixed finger somewhat narrow near the base, yet considerably thicker than the movable finger, slightly
decreasing in breadth from near the base to somewhat beyond the middle and with most of the in-
cisive margin straight; movable finger somewhat shorter than the anterior margin of the hand, rather
narrow, towards the base not touching the other finger, and when the distal parts of the fingers are
crossed, a conspicuous interval is left between their more proximal parts, but especially at the base
this interval is a good deal narrower than in P. abyssi or P. forcipatus.

Fifth thoracic segment a little shorter than the three preceding segments combined and as long
as the sixth. — The thoracic legs of moderate length and thickness (fig. 1b). Second pair (fig. 6b)
with the sixth joint elongate, even slightly longer than fifth and fourth joints combined, much taper-
ing towards the end and almost half as long again as seventh joint with claw. Third pair with the
sixth joint about as long as the fifth plus half of the fourth and not fully twice as long as seventh
joint with claw; the spur on fifth joint half as long as sixth joint, broad at the base but near the
base somewhat abruptly much thinner and then tapering to the acute end. Fourth pair (fig. 6c) in
the main as the third, but fifth to seventh joint somewhat shorter and the short basal part of the
acute spur is very broad. Seventh pair (fig. 6d) with sixth joint slightly longer than the fifth and
twice as long as seventh with claw; the spur somewhat slender.

30 CRUSTACEA MALACOSTRACA. II.

The abdomen somewhat longer than the two posterior thoracic segments combined. Pleopods
well developed, with long sete. — Uropods (fig. 1d) with very long terminal setee; endopod somewhat
robust with the proximal joint slightly longer than the distal; exopod only a little shorter than the
endopod but considerably thinner, with the proximal joint slightly shorter than the distal.

Length of a female with the marsupial lamellz less than half developed 1.9™™.

Remarks. P. oculatus differs from P. forcipatus and P. Lilljeborgii by possessing well devel-
oped pleopods, the exopod of the uropods much longer than the proximal joint of the endopod, etc.;
it differs from P. adysst in the chele, shorter and proportionately thicker legs, longer exopod of the
uropods, etc., from P. affinis by features in nearly all appendages. It is on the whole more allied to
P. mediterraneus G. O. S. than to any species described in the present paper, but differs from it in
having the claw of second pair of legs shorter and in various minor features in the antennz and
thoracic legs. And above all it differs from P. mediterraneus and all species described from Norway
or in the present paper in possessing real eyes with several well developed cornez.

Occurrence. Taken by the “Ingolf” at a single station.

Davis Strait: St. 34: Lat. 65°17’ N., Long. 54°17’ W., 55 fm.; 1 spec.

Besides it has been captured at West and East Greenland by three other collectors.

West Greenland: Upernivik, Lat. 72°48’ N., July 21, 1887; 1 spec. Ryder.

Davis Strait: Lat.65°27'N., Long. 54°45’ W., 67 fm., temp. 1.1°; 1 spec. Wandel.

East Greenland: Angmagsalik, ab. Lat. 65°30’N. Aug. 7, 1902; 1 spec. Mag. sc. Kruuse.

18. Pseudotanais affinis H. J. Hansen.
(Pl. III, figs. 2a—20, and? figs. 3a—3b.)
1886. Pseudotanais affinis H. J. Hansen, Dijmphna-Togtets zool.-bot: Udbytte, p. 207; Tab. XX],
Fig. 2 (Female).
_— — crassicornis FH. J. Hansen, 1. ce. p. 208; Tab. XXI, Fig. 3, 3a (Subadult Male).
Female. The body about five times as long as broad. — Front margin of the head only
about one-third as long as the breadth of the carapace (fig. 2a), somewhat sinuate, being conspicuously
convex at the middle, a little emarginate behind each antennula and with the lateral angles distinctly
produced. No eyes.
The antennulz are moderately long, somewhat more than half as long again as the carapace
(fig. 2a). First joint, seen from the side (figs.2b and 2d), with the basal fourth considerably expanded
below, four and a half to five times as long as deep, at the base broader than deep and seen from
above (fig.2a) abruptly narrowed slightly beyond the middle. Second joint about three times as long
as deep; third joint slender, from a little longer to one-third as long again as the second. — Antenne
moderately slender; second and third joints (fig.2d) on the distal upper angle with a spiniform, strong
process; fourth joint nearly two and a half times as long as the penultimate.
Chelipeds rather slender. Chela (fig. 2e) more slender than in the preceding species, from a
little more than three times to more than three and a half times as long as broad, with the posterior
margin considerably concave at the. middle; the fixed finger moderately slender and tapering from

CRUSTACEA MALACOSTRACA. II. 31

the base; the movable finger nearly as long as the front margin of the hand, conspicuously more
slender than the fixed finger; when the distal parts of the fingers are crossed there is a narrow or
no interval between their proximal halves.

Fifth thoracic segment about three-fourths as long as the three preceding segments combined
and scarcely longer than the sixth segment. — Thoracic legs moderately long and rather slender, but.
the posterior pairs vary a little in this respect. Second pair (fig. 2f) with sixth joint almost as long
as fifth and fourth joints combined and a little shorter than seventh joint with claw. Third pair
(fig. 2g) with the sixth joint only a little longer than the fifth and not fully twice as long as seventh
joint with claw; the spur on fifth joint about, or more than, half as long as sixth joint, strongly nar-
rowed a little beyond the very broad base (fig. 2i) and with the distal half conspicuously expanded,
forming a very oblong plate with the end subacute or narrowly rounded. Seventh pair (fig. 2h) with
fifth joint somewhat longer than the sixth, which is not fully twice as long as seventh joint with
claw; the spur not half as long as sixth joint, moderately narrow or somewhat thin, not expanded at
the middle.

Abdomen almost as long at the two preceding thoracic segments combined. — Pleopods well
developed; the longest setee about three times as long as their rami and on the posterior pairs even
reaching the end of the uropods. — Uropods (fig. 2 c) somewhat long and slender; the endopod with
the proximal joint slightly longer than the distal; the exopod reaches about the middle of the distal
joint of the endopod, and its proximal joint is always considerably shorter than the distal.

Length of the largest female with marsupium (from the Kara Sea) 2.2™", of large specimens
without marsupium 2.1™™,

Subadult Male. The most characteristic difference between subadult males and the other
sex are the antennulee (fig. 21), which have the first joint much thicker, the second somewhat to much
thicker, than in the other sex; the third joint is slender with a thickening below at the base. Fifth
and sixth thoracic segments somewhat shorter as compared with the three anterior segments than in
the females. The chele (fig. 2m) and the thoracic legs (fig. 20) vary conspicuously as to thickness.
Pleopods and uropods as in the females.

Variety. At Stat. 25 the “Ingolf? captured a number of specimens, all immature and of both
sexes, which in some particulars differ from the other material. The largest female is only 1.4™™, the
largest subadult male 1.3™™. In the females the antennule (fig. 2k) are distinctly less slender than
usual, with first joint about four times as long as deep; the antennz are conspicuously thicker (fig. 2k)
with the fourth joint only twice as long as the penultimate, while second and third joints have a
slender spine instead of a stronger process on their upper distal angle. The chelce about three times
as long as broad; the thoracic legs on the whole a little more robust and the spur on third pair
scarcely as long as and somewhat more spiniform than in the typical form. The uropods normal. —
In the subadult male the antennule (fig. 2n) have first and second joints much thickened, but the
third joint is more than half as long again as the second, the thickening is not confined to the short
proximal part but reaches to near the middle of the joint, and the proximal half of the joint is dis-
tinctly conical, the distal half cylindrical. The antennz nearly as in the female, with the fourth joint
slightly thicker.

32 CRUSTACEA MALACOSTRACA. II,

The main differences between this variety and the normal form are thus the slender spines
instead of processes on second and third joints of the antenne, the shape of the proximal half of
third antennular joint in the male, and the fact that the appendages of both head and thorax are on
the whole more robust. But I think it improbable that these differences are of specific value; adult
females with marsupium ought at least to be procured before the variety may possibly be separated
as a new species. ; 2, :

Remarks. I established P. affinis on 3 females from the Kara Sea, while the insufficiency
of the literature on the genus and my very scanty material induced me to establish P. crassicornis
on a subadult male. I find it useful to insert here a more detailed description of female and sub-
adult male together with a number of figures, as I now possess a rich material both of this species
and of other forms.

P. affinis is closely allied to P. macrocheles G. O. Sars, but if the figures published by Sars
(1897) are correct, the latter species differs especially in the outer ramus of the uropod, which is
shorter and showing a proportion between its joints quite different from the features found in P. af
Jinis ; besides Sars has figured the antennulz with a strong seta, while a process is found in the typ-
ical specimens of P. affnis. Sars’ figures of the legs differ also in minor particulars from P. a/fnis.

Adult Male (Pl. III, figs. 3a—3b). A single adult male has been taken (at “Ingolf” St. 124)
together with two females. But though this specimen considerably resembles the male of P. forcipatus,
I am not quite sure that it belongs to P. affnis. The head, seen from the side (fig. 3a), has the an-
tero-lateral lobe still longer than in P. forcipatus, broadly rounded. — The antennule have the fifth
joint slightly shorter than the sixth, which is scarcely as long as the seventh. — The antennz thicker
than in the female; third joint proportionately long, as long as the penultimate joint, with a rather
long spine on the distal upper angle. — The chele shaped as in the male P. forcifatus, somewhat
more than twice as long as broad; the fixed finger at the base more than twice as broad as the
movable, which is somewhat shorter than the front margin of the hand; a narrow interval is seen
between the subdistal portions of the fingers.

Second pair of legs (fig. 3a) with the sixth joint a little shorter than the two preceding joints
combined, but as long as seventh joint with claw. Fourth pair of legs uncommonly short, only two-
thirds as long as the sixth pair; fifth pair, which are poorly preserved, seem also to be somewhat
short. The three posterior pairs have the sixth joint a little shorter than seventh joint with claw.

The abdomen as to the shape of the lateral margins (fig. 3b) and other particulars nearly as
in P. forcipatus, but sixth segment is proportionately longer and more produced backwards, reaching
slightly beyond the end of first joint of the endopod of the uropods, while the posterior margin is
somewhat broad and deeply emarginate as in P. forcipatus. — The uropods differ much from those
of the female; the endopod has the proximal joint much longer than the distal, the exopod reaches
slightly beyond the proximal joint of the endopod and its first joint is somewhat longer than
the second.

Length of the single male 1.36™".

The shape of the chelz and especially the relative length of the joints in the uropods as com-
pared with the corresponding organs of the female ?. a/finis make the reference of the adult male to

CRUSTACEA MALACOSTRACA. II. 33

this species somewhat uncertain, though, on the other hand, the antennulz, the chelz, the second
pair of legs and the shape of the last abdominal segment show close relationship to the above-de-
scribed males of the two other species of this genus, and no other species of the genus is known to
which the male might possibly belong. For these reasons I have described and figured this male
and referred it, with a query, to P. affinis.
Occurrence. The “Ingolf’ has captured this species at twelve stations.
Davis Strait: St. 32: Lat. 66°35' N., Long. 56°38’ W., 318 fm., temp. 3.9°; 3 spec.
_ St. 25: Lat. 63°30’ N., Long. 54°25’ W., 582fm., temp. 3.3°; 13 spec.,
described above as a variety.
— St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 3 spec.
South-West of Iceland: St. 78: Lat. 60°37’ N., Long. 27°52’ W., 799 fm., temp. 4.5°; I spec.
North-West of the Feeroes: St. 138: Lat. 63°26’ N., Long. 7°56’ W., 471 {m., temp. + 0.6°; 4 spec.
~ -_ - _ St. 139: Lat. 63°36’ N., Long. 7°30’ W., 702{m., temp. + 0.6°; 1 spec.
East of Iceland: St. 103: Lat. 66°23’ N., Long. 8°52' W., 579 fm., temp. + 0.6°; 3 spec.
—- - — St. 102: Lat. 66° 23’ N., Long. 10°26’ W., 750fm., temp. + 0.9°; 1 spec.
— -. = St. ror: Lat. 66° 23’ N., Long. 12°05’ W., 537 fm., temp. + 0.7°; 3 spec.

North of Iceland: St. 124: Lat. 67°40’ N., Long. 15°40’ W., 495 fm., temp. + 0.6°; 3 spec.
North-East of Iceland:* St. 119: Lat. 67°53’ N., Long. 10° 19' W., 1or10 fm., temp. + 1.0°; 6 spec.
South of Jan Mayen: St. 116: Lat. 70°05’ N., Long. 8°26’ W., 371 {m., temp. + 04°; I spec.

Besides the species has been secured by the II¢ Amdrup Exped. at a single locality.
East Greenland: Forsblad Fjord, at Lat. 72°27'N., Long. 25°28’ W., 50—g0 fm.; 1 spec.

Distribution. The type specimens were taken in the Kara Sea, 64—65 fm. (H. J. Hansen).
— According to the list of localities the species has been taken four times in the warm area in depths
from 318 to near 1200 fm., and the highest temperature is 4.5°, but besides it is widely distributed in
the cold area in depths from 371 to 1010 fm. and the lowest temperature was + 1.0°; finally it has

been captured at cold localities in the northern East Greenland and the Kara Sea in much lesser

depths, viz. between 50 and go fm.

19. Pseudotanais longipes n. sp.
(Pl. III, figs. 4a—4i.)

Female. The body scarcely four times as long as broad. — Carapace strongly tapering in
breadth forwards (fig. 4b), with the lateral margins not much convex; the anterior margin, which is
even a little less than one-third as long as the breadth of the carapace somewhat before its hind
margin, is feebly concave at each antennula. — Eyes wanting.

Antennule very elongate, twice as long as the carapace (fig. 4a) and extremely slender (fig. 4c).
First joint more than six times as long as deep though its proximal part is somewhat thickened be-
low, slightly longer than the two other joints combined; second joint not half as long as the third;

the sete on all joints extremely long. — The antenne (fig. 4c) are very slender; third joint shorter

The Ingolf-Expedition. III. 3. 5

34 CRUSTACEA MALACOSTRACA. II.

than deep and much shorter than the second; fourth joint extremely long, almost four times as long
as the penultimate joint, which is conspicuously longer than second and third joints combined.

Chelipeds somewhat long and slender (fig. 4a). Carpus twice as long as the basal joint and
three times as long as deep. Chela a little less than half as long again as the carpus, four and a
half times as long as broad (fig. 4d); the fixed finger at the base somewhat broader than the movable
and keeping almost the same breadth to beyond the middle; the movable finger slender, tapering
from near the base to the end, and the fingers without any interval between them when their ter-
minal parts cross each other.

Fifth thoracic segment slightly longer than the three preceding segments combined, or than the
sixth segment. — The legs extremely long and very slender; second pair with the sixth joint, though
very long, scarcely as long as the sum of the two preceding joints but somewhat longer than seventh
joint with claw, and the claw almost twice as long as seventh joint. Third pair (fig. 4f) with the sixth joint
slightly shorter than the fifth and slightly longer than seventh joint with claw; the spur on fifth
joint is a very long, slender spine. Fourth pair in the main as the third pair; the spur on fifth joint
is a slender spine more than two-thirds as long as the sixth joint (fig. 4g) which is considerably
longer than seventh joint with claw. — Seventh pair (fig. 4h) with the sixth joint slightly longer
than the fifth and about two and a half times as long as seventh joint with claw.

Abdomen slightly longer than seventh, sixth and half of the fifth thoracic segment combined.
Pleopods with slender rami and long sete. — Uropods long and very slender (fig. 41); the endopod
with the proximal joint somewhat longer than the distal; the exopod reaches a little beyond the
middle of the distal joint of the endopod, but its division into two joints could not be perceived with
certainty; one of the terminal sete of the exopod is nearly three times as long as the ramus itself
and a little longer than the longest terminal seta of the endopod,

Length of the immature female drawn (the marsupial lamellee are small) 1.60"; another female
without marsupium measures 1.95™".

Remarks. P. longipes is easily distinguished from all other species of the genus by its ex-
tremely long and slender antennule, legs and uropods and the long and narrow chele.

It was taken at the station, where the trawl was filled with an enormous quantity of sponges,
and it is of interest to note, that Zyphlotanais eximius n.sp., which possesses chelee more narrow and
longer than any other species of the genus, and besides a most curious, extremely long-legged species
of the sub-order Asellola have been taken at the same station. Judging from these facts I am in-
clined to suppose that such long-legged species have been developed under the influence of the en-
vironment, the sponges, and have been adapted to live on that peculiar ground.

Occurrence. This species has been taken by the “Ingolf” at a single station.

South-West of Iceland: St. 78: Lat. 60°37’ N., Long. 27°52’ W., 799 fm., temp. 4.5°; 3 spec.

Paratanais Dana.

This genus comprises at present nine species, but only a single form is known from the area

investigated.

CRUSTACEA MALACOSTRACA. II. 35

20. Paratanais Batei G. O. Sars.

1884. Paratanais Batei G. O. Sars, Arch. for Math. og Naturv. B. 4, pi 32.
! 1896. — its Account Crust. Norw. Vol. II, p. 16, Pl. VII.
Occurrence. This well-known species has not been taken by the “Ingolf”, but by two tra-
velling Zoologists. |
South of Iceland: Vestmannaeyjar, the littoral belt, Aug. 21, 1899; 1 spec. Mag. B. Seemundsen.
The Feroes: Vestmanhavn, 1o—30 fm., June 2, 1899; 1 spec. Dr. Th. Mortensen.
Distribution. P. Bate? has been taken “in several places on the west coast of Norway, in
comparatively shallow water among the roots of Laminarie” (G. O. Sars). Furthermore it is known
from some places on both sides of Scotland (T. Scott), from Falmouth and Plymouth (A. M. Norman),
Galway Bay in Ireland, 5—15 fm. (Tattersall), the Channel Islands (various authors), Saint-Jan-de-Luz
in S. W. France, 2"/, fm. (Dollfus), finally from the Mediterranean at Spezia, 6—r10 fm. (G. O. Sars)
and the Gulf of Naples, 1—1'/, fm. (G. Smith).
| P. Batet is decidedly a shallow water species, and its occurrence near South Iceland is of interest,
as some other Crustacea from the Lusitanican area also occur there and have their limit of distri-

bution in north-western direction at that coast.

Typhlotanais G. 0. Sars.

This genus hitherto comprised sixteen species, of which nine are known from Norway. The
“Ingolf? material comprises nineteen species, but sixteen of these are new, while three are dealt with
in the work of Sars. The sixteen new species were all taken in depths ranging from 293 to 1870
fathoms, and the majority exclusively in depths from 690 to 1870 fathoms, but even eleven of these
species were captured only at a single station and seven among them I establish on a single spe-
cimen. Judging from these facts I am tolerably sure that several and probably numerous species of
this genus living in the area explored by the “Ingolf” are still undiscovered, furthermore that the
depths of the oceans, from about 400 to at least 2000 fathoms, must contain a very large number of
species of this genus.

Sars has published a good description of the genus according to the species seen by him. But
some of my new species differ conspicuously from that description in a few points. Thus, some species
have the lateral margins of the thoracic segments very angular, while Sars said that the lateral con-
tours of the body are almost straight; 7: macrocephala has the cephalothorax extremely large, the an-
tennulz much thicker and the chele broader than allowable according to Sars’ diagnosis. But I have
found it impossible not only to separate a single form or some species as a new genus, but even to
divide my nineteen species into moderately well separated groups, because the characters are inter-
mingled in such a way and so gradually developed in various species, that no natural division of any
value could be discovered.

The scantiness of my material of the majority of the new species rendered it impossible to
examine their mouth-parts. But I have examined these parts of one of the species most aberrant

from the forms studied by Sars, viz. 7: zvregularis n. sp. and found that they differed so little from
ae

36 CRUSTACEA MALACOSTRACA. II.

the figures published by Sars that the only feature worth mentioning is, that the movable lobe on
the left mandible is very large, being a little longer and probably broader than the incisive lobe.
Consequently, I suppose that Sars’ description and figures in all points of any importance hold good
for all species described in the following pages. :

The genus 7yphlotanais (females and immature males) may be characterized by the following
diagnosis. Eyes wanting. Antennule three-jointed; first joint at least as long as and generally longer
than the two other joints combined, second joint proportionately short. Antenne with fourth and
fifth joints completely fused, without any suture between them. Mandibles well developed with their
molar process cylindrical or even a little thicker at the obliquely cut, dentate end. Chele slender, at
least two and a half times as long as broad. Second pair of legs differ conspicuously from third or
fourth pair by having seventh joint with claw considerably longer. Pleopods well developed in the
female. Uropods with the rami slender, two-jointed or one-jointed. Incubatory pouch consists of four
pairs of lamellae. — (Adult males of all species unknown excepting of 7: fmmarchicus G. O. S.,. which
has been described by Sars).

21. Typhlotanais irregularis n. sp.
(Pl. III, figs. 5a—5e.)

Female. Body moderately robust, somewhat more than five times as long as broad. — Cara-
pace somewhat or considerably shorter than the two next ‘segments combined, a little longer than
broad, with the lateral margins somewhat convex, the front margin two-thirds as long as the posterior
and the median process moderately long, acute.

Antennule (figs. 5a and 5b) considerably shorter than the carapace, rather stout. First joint
considerably longer than the two other joints combined, not fully two and a half times as long as
deep and tapering considerably and gradually from a little from the base to the end; second joint
scarcely as deep as long and about half as long as the third; the longest terminal seta scarcely as
long as third and second joints combined. — Antennze moderately robust; third joint not thickened;
fourth considerably less than twice as long as the penultimate joint; terminal sete scarcely as long
as those of the antennule.

Chelipeds (fig. 5b) moderately strong: Basal joint with the proximal protuberance somewhat
short; the distance between its posterior end and the front lower angle of second thoracic segment
about as long as the basal joint. Carpus distinctly longer than the basal joint and almost twice as
long as deep. Chela (fig. 5c) distinctly longer than the carpus, about three times as long as broad;
movable finger somewhat longer than. the front margin of the hand; both fingers very acute; fixed
finger near the base considerably broader than the movable and with an acute tooth somewhat from
the end of the incisive margin.

Thoracic segments (fig. 5a) peculiarly shaped, decreasing in breadth from second to seventh,
the latter being only slightly more than half as broad as the second; furthermore the segments in-
crease a little in length from the second to the fourth and then decrease to the seventh. Second seg-

ment decreases very conspicuously in breadth from the antero-lateral, protruding angles to the pos-

CRUSTACEA MALACOSTRACA. IT. 37

terior margin; it is unusually large, slightly more than half as long as the carapace, somewhat or
a little less than twice as broad as long, a little or somewhat shorter than third segment and without
any process below. Third to seventh segments with their lateral margins strongly angular or, in the
three posterior segments, very convex, but the angles or the broadest place of the segment is on the
third segment situated not much behind the front margin, on the fourth a little more backwards, on
the fifth at the middle, on the sixth somewhat behind the middle and on the seventh a little before
the posterior margin. — The legs are rather long and slender; second pair have the sixth joint (fig. 5b)
almost as long as fifth and fourth joints combined and only a little longer than seventh joint with
claw; the few sete of the legs short. Third pair rather similar to second, but sixth joint is a little
shorter and seventh joint with claw only about two-thirds as long as sixth joint; setee short. Fourth
pair completely as the third. Seventh pair (fig. 5d) slender; second joint almost five times as long
as broad; fourth and fifth joints not expanded, with a tooth-shaped spine at the distal posterior angle;
sixth joint somewhat longer than the fifth; seventh joint with claw more than half as long as
sixth joint.

Abdomen scarcely as long as the two preceding segments combined. — Uropods long and
slender (figs. 5a and 5e); endopod two-jointed, with first joint somewhat or a little less than twice as
long as the second; the exopod reaches the middle of the distal joint of the endopod and seems to be
undivided.

Length of a female with marsupium 1.6™", of a large female without marsupium 1.85™™.

Subadult Male. Differs from the female only in the antennulz, which have the distal part
of first joint and the whole second joint somewhat thicker than in the female, while the third joint
has the basal part distinctly thickened on the lower side.

Remarks. TZ. wregularis is easily distinguished from all other forms of the genus excepting
T. macrocephala un. sp. and 7. mucronatus n. sp. by the shape and relative length and breadth of the
thoracic segments; the rather short antennulz, the legs and the uropods afford further characters. It
bears some resemblance to 7: macrocephala, but the latter species is easily distinguished by its ex-
tremely large carapace, the enormous process on the lower side of second thoracic segment, etc. From
T. mucronatus it is easily separated by the widely. different antennze, short sete on the legs, etc.

Occurrence. The “Ingolf’ has taken this fine species at twelve stations, all in the cold area.

North of the Feroes: St. 141: Lat. 63°22’ N., Long. 6°58’ W., 679 fm., temp. + 0.6°; 22 spec.

comand nikita — St. 139: Lat. 63°36’ N., Long. 7°30’ W., 702 fm., temp. + 0.6°; ab. 50 spec.
East of Iceland: St. 104: Lat. 66°23'N., Long. 7°25’ W., 957 fm., temp. + 1.1°; I spec.
et St. 103: Lat. 66°23'N., Long. 8°52’ W., 579 fm., temp. + 016°; 1 spec.
mR ae St. 102: Lat. 66°23’ N., Long. 10°26’ W., 750 fm., temp. + 0.9°; 21 spec.
North of Iceland: St. 126: Lat. 67° 19' N., Long. 15°52’ W., 293 fm., temp. + 0.5°; 2 spec.

ot Se ae St.125: Lat. 68°08’ N., Long. 16°02’ W., 729 fm., temp. + 0.8°; 12 spec.
North-East of Iceland: St. 120: Lat. 67°29! N., Long. 11°32’ W., 885 fm., temp. + 1.0°; 2 spec.
i - — $t.119: Lat. 67°53'N., Long. 10°19’ W., rorofm., temp. + 1.0°: 2 spec.
South of Jan Mayen: St.118: Lat. 68°27'N., Long. 8°20’ W., 1060fm., temp. + 1.0°; 6 spec.
SNES am St.117: Lat.69°13’N., Long. 8°23' W., 1003 fm., temp. + 1.0°; ab. 40 spec.

38 CRUSTACEA MALACOSTRACA. II.

South of Jan Mayen: St.113: Lat. 69°31" N., Long. 7°06' W., 1309 fm., temp. + 1.0°; 7 spec.
Distribution. A single ovigerots female has been found between some material from the
Kara Sea brought home by the “Dijmphna” Expedition,

22. Typhlotanais macrocephala n. sp. |
(Pl. III, figs. 6a—6e)

Specimen without marsupium. Body almost five and a half times as long as broad. —
Carapace (fig.6a) exceedingly large, nearly longer than second, third and half of fourth segment com-
bined, considerably longer than broad; the anterior margin only a little shorter than the posterior,
with the frontal process constituting a broad, rather low triangle with the margins along the base of
the antennule very feebly concave; the carapace is broadest at the end of the anterior two-thirds,
and the major part of its lateral margins are somewhat convex and posteriorly with a few saw-teeth
or fine indentations. ©

The antennule (fig. 6b) are short and thick, conical, only half as long as the carapace. First
joint about half as long again as deep; the two distal joints combined about as long as the depth of
the first joint; second joint much deeper than long; third joint proportionately thick at the base, conical,
with the terminal sete about as long as the first joint. — Antenne short and moderately thick; third
joint not thickened, fourth considerably less than twice as long as the penultimate joint; terminal
setee nearly as long as those of the antennule.

Chelipeds somewhat small (fig. 6b). Posterior protuberance on the basal joint short; the dis-
tance between its hind margin and the anterior lower angle and second thoracic segment considerably
longer than the basal joint. Carpus considerably longer than the basal joint, about twice as long as
deep. Chela a little longer than the carpus, only about two and a half times as long as broad;
movable finger distinctly longer than the front margin of the hand; fixed finger thick at the base,
with a tooth before the end.

Thoracic segments (fig.6a) somewhat similar in general shape and relative dimensions to those
of Z:irregularis, but the major posterior part of the lateral margins of second to fourth segment with
four or five distinct teeth (fig. 6c). Second segment slightly narrower than the carapace, not fully
twice as broad as long, broadest at the angle a little behind the anterior margin and decreasing much
in breadth posteriorly; seen from the side (fig. 6b) this segment is expanded downwards below and
the expansion produced in an enormous process, the base of which is as long as the segment, while
the posterior margin is regularly convex, the anterior margin deeply concave and the end of the pro-
cess acute and directed somewhat forwards. ‘Thitd’ segment scarcely longer and considerably nar-
rower than the second but otherwise nearly of the same shape (fig. 6a); fourth segment about as long
as the third but distinctly narrower and of similar shape. Fifth and sixth segments each scarcely as
broad as the fourth and only a little more than half ‘as broad as the carapace, while seventh segment
is as broad as the fourth; the lateral margins of all three segments are considerably convex and more
or less distinctly angular; fifth segment broadest a little behind the middle and the two other seg-
ments broadest somewhat behind the middle; the fifth segment has a few nearly rudimentary teeth

CRUSTACEA MALACOSTRACA. II. 39

on the posterior part of the lateral margins. — Thoracic legs moderately long and rather slender;
second pair (fig. 6b) with sixth joint only a little shorter than fifth and fourth joints combined and
slightly longer than seventh joint with claw; sete short. Third pair with sixth joint as long as the
fifth plus half of the fourth; seventh joint with claw as long as fifth joint; setee short. Seventh pair
(fig. 6d) moderately long; second joint slender, nearly five times as long as broad; fourth and fifth
joints moderately broad but scarcely expanded and without any armature; sixth joint proportionately
somewhat stout, being not much thinner than the fifth and about as long as the fifth plus half of
the fourth; seventh joint with claw quite short.

Abdomen as broad as the last thoracic segment, with the sides somewhat convex, a little
shorter than the two preceding segments combined. — Uropods of moderate length (fig. 6e); endopod
two-joiuted with the proximal joint somewhat longer than the distal; exopod a little shorter than the
endopod, two-jointed, with the proximal joint a little shorter than the distal.

‘Length of the single specimen (probably a female) 1.20™".

Remarks. This species differs from all other forms of the genus by its gigantic carapace,
the very short and thick antennule, the huge process on the lower side of second thoracic segment
and the serrate lateral margins of the three (four) anterior thoracic segments. In sonie other features
and especially in the dorsal aspect of the thoracic segments it resembles considerably 7: irregularis n. sp.

Occurrence. The single specimen has been captured by the “Ingolf”.

South-West of Iceland: St.78: Lat. 60°37' N., Long. 27° 52’ W., 799 fm., temp. 4.5°; 1 spec.

23. Typhlotanais pulcher n. sp.
(Pl. IV, figs. 1a—z g.)

Specimen without marsupium. Body very slender, more than eight times as long as
broad. — Carapace considerably longer than broad but only slightly longer than the unusually long
second thoracic segment (figs. 1a and rb), lateral margins rounded posteriorly and from there converg-
ing gradually forwards to the anterior margin, which is somewhat longer than half of the breadth
of the carapace, and the rostral process is somewhat long, subacute.

Antennule (figs. rb and 1c) nearly as long as the carapace, moderately slender. First joint
somewhat longer than the two other joints combined, about three and a half times as long as deep,
and, seen from the side, not tapering, which renders it probable that the specimen may be an imma-
ture male; second joint about as long as deep, not half as long as the third joint, which has its
proximal part slightly thickened on the lower side; terminal sete as long as the two distal joints
combined. — Antennze moderately slender; third joint not thickened; fourth joint a little more than
twice as long as the penultimate, and both these joints with long sete at the end, while the setz of
the terminal joint are still longer, though a little shorter than the longest terminal antennular sete.

Chelipeds (fig. 1c) moderately slender. Basal joint with the proximal protuberance scarcely free
and of moderate length; its posterior end far removed from the front lower end of second thoracic
segment. Carpus a little less than three times as long as deep. Chela a little longer than the carpus,

three times as long as broad; movable finger rather slender and much longer than the front margin

40 CRUSTACEA MALACOSTRACA. II.

or the hand; fixed finger towards the base much broader than the movable and with about three
sharp teeth along the distal part of the incisive margin.

Thoracic segments extremely characteristic (fig. ra). Second segment almost as long as the
carapace or third segment and slightly longer than the fourth; each lateral margin is a straight line
and the lateral margins converge considerably from the anterior to the posterior end; no ventral pro-
cess is found. Third segment similar to the second excepting that it is broadest somewhat behind
the anterior margin and the somewhat short anterior part of the lateral margin between its front end
and the lateral angle is even concave. Fourth segment shaped nearly as the third. Fifth segment
even slightly shorter and somewhat narrower than the fourth, with the major part of the lateral mar-
gins subparallel and the margins rounded and converging towards both ends. Sixth segment con-
siderably shorter than the fifth and almost twice as long as the seventh, and both these segments in-
crease somewhat in breadth from the anterior end to respectively somewhat from or near to the pos-
terior margin. — Thoracic legs very different from each other. Second pair (fig. rc) long and slender;
fifth joint at the anterior distal angle with a seta as long as the joint; sixth joint considerably longer
than the fifth and somewhat shorter than seventh joint with claw. Third pair (fig. 1d) considerably
shorter than second, very slender; sixth joint conspicuously shorter than the fifth, nearly twice as long
as seventh joint and with its anterior distal setee somewhat long. Three posterior pairs (figs. re and rf)
moderately slender; second joint nearly four times as long as broad; fifth joint with the distal half
somewhat expanded; sixth joint moderately long and somewhat slender, a little more than half as
long again as seventh joint with claw.

Abdomen slightly longer than the two preceding segments combined (fig. 1a), somewhat oval,
posteriorly nearly truncate with a low, rounded median protuberance. — Uropods (fig. 1g) short;
endopod two-jointed with first joint somewhat longer than the second; exopod one-jointed, slightly
longer than the proximal joint of the endopod.

Length of the specimen, which according to the antennule seems to be an immature
male;:277 2:

Remarks. This species, taken in very great depth, differs strongly from all other species of
the genus by the shape and especially the relative length of the thoracic segments, the differences
being in reality so great that one is tempted to regard them as being of generic value, but antennulz,
antennee, chelipeds, thoracic legs, pleopods and uropods agree with structural features frequently found
in Z7yphlotanais. The long seta at the end of fifth joint of second pair of legs is certainly a good
specific character.

Occurrence. The single specimen has been taken by the “Ingolf”.

South of the Davis Strait: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870 fm., temp. 1.3°; 1 spec.

24. Typhlotanais gracilipes n. sp.
(Pl. IV, figs. 2a—2e,)
Female (without marsupium).. Body very slender, almost eight times as long as broad. —
Carapace (figs. 2a and 2b) long and narrow, as long as second, third and the half of fourth segment

CRUSTACEA MALACOSTRACA. II. 41

combined, more than half as long again as broad; the lateral margins feebly convex posteriorly and
then converging to the front angles; the anterior end slightly more than half as broad as the carapace
a little from the hind margin; rostral process moderately long, somewhat narrow, acute.

Antennule (figs. 2a and 2b) considerably shorter than the carapace, somewhat robust. First
joint a good deal longer than second and third joints combined, not fully three times as long as deep
and tapering considerably to the end; second joint about as long as deep; third joint conspicuously
more than twice as long as the second, thin, with the longest terminal seta scarcely longer than the
joint. — Antenne of usual size; third joint not thickened; fourth joint not twice as long as the pen-
ultimate and with long setee from its distal lower angle; longest terminal setee much longer than
those of the antennule.

Chelipeds very slender (fig. 2b). Basal joint with the posterior process moderately long and
its proximal margin rounded ; the distance between this margin and the front lower end of second
segment only a little shorter than the basal joint. Carpus almost twice as long as the basal joint and
a little more than three times as long as deep. Chela small, somewhat shorter than the carpus, three
and a half times as long as broad; movable finger slightly longer than the anterior margin of the
hand; fixed finger near the base considerably broader than the movable.

Thoracic segments, as far as could be ascertained in the mutilated specimen, in the main as
in 7. mucronatus un. sp. (comp. description and figs. 3a of this species), but the difference between the
anterior and the posterior breadth of each segment seems to be a little smaller and the lateral margins
of the segments a little less convex (fig. 2a). Second segment (figs. 2a and 2b) only slightly more
than half as long as the third and without ventral process. -- Thoracic legs on the whole slender.
Second pair (fig. 2b) slender and moderately long; fourth and fifth joints with the distal anterior sete
somewhat long; sixth joint long, only a little shorter than fifth and fourth joints combined and without
any perceptible distal anterior seta; seventh joint with claw nearly as long as sixth joint. Third pair
mutilated, but scarcely much different from fourth pair (fig. 2c) which is very slender, much shorter
than second pair, with a rather long seta on the distal anterior angle of fifth joint, sixth joint con-
siderably longer than the fifth but slightly longer than seventh joint with claw. Three posterior
pairs of legs peculiarly built and unusually long (fig. 2d); second joint not fully four times as long
as broad; fourth and fifth joints somewhat slender, though considerably and gradually widened on the
anterior side towards the end, and there with a couple of somewhat long, slender spines, fifth joint
besides with a couple of slender spines on the terminal inner margin; sixth joint not much longer
than the fifth, moderately slender; seventh joint and the short, thin claw combined somewhat more
than half as long as sixth joint.

Abdomen about as long as the two preceding segments combined. — Uropods mutilated, but
one exopod (fig. 2e) has been preserved; it is long, very slender, perhaps undivided, but the seta gen-
erally found just before the articulation is long and originates even slightly beyond the middle.

Length of the single specimen 2.05 ™".

Remarks. 7. gracilipes is easily distinguished from all species of 7yfhlotanats described in
this paper by its slender, small chelipeds and the peculiar three posterior pairs of thoracic legs with

the long and slender spines on fourth and fifth joints. It is closely allied to 7: microcheles G. O. S.,
The Ingolf-Expedition. III. 3. 6

42 CRUSTACEA MALACOSTRACA. II.

but according to Sars’ figures and my examination of some of his co-types it differs in some parti-
culars. In Z- microcheles the chelipeds have the basal joint about three-fourths as long as the carpus,
thus considerably longer than in 7: gracilifes, and their carpus is deeper, scarcely two and a half
times as long as deep; furthermore the thoracic legs are on the whole a little more robust than in
T. gracilipes. In a specimen of 7. microcheles with the ventral side of the anterior thoracic segments
flat and without marsupium no ventral process on second segment is found, but in three other spe-
cimens presented by Sars the ventral surface of the anterior segments is convex, the second segment
has a very large, long and broad, oblique-triangular, acute ventral process directed forwards and down-
wards, and each of the four following segments has a somewhat smaller but yet far from small, acute,
somewhat curved ventral process.
Occurrence. The single specimen was taken by the “Ingolf”,

South of Iceland: St. 54: Lat. 63°08’ N., Long. 15°40’ W., 691 fm., temp. 3.9°; I spec.

25. Typhlotanais mucronatus n. sp.
(Pl. IV, figs. 3a—3h.)

Female (without marsupium). Body slender, about six and a half times as long as broad. —
Carapace (fig. 3b) somewhat small, slightly broader than long, a little longer or somewhat shorter
than second segment plus half of the third; the lateral margins are somewhat convex, the anterior
margin is even a little more than two-thirds as long as the breadth of the carapace and the frontal
process very broad, proportionately rather low and broadly rounded.

Antennule (figs. 3b and 3c) extremely long and slender, a little longer than carapace and se-
cond thoracic segment combined. First joint a little longer than the two other joints together, very
slender excepting its proximal fourth, which is considerably thickened below and its depth is here
about one-fifth of the length of the joint; seen from above (fig. 3b) the joint is rather broad at the
base, tapers considerably to beyond the middle, where it is abruptly narrowed a little and its distal part is
subcylindrical. Second joint is thin, almost three times as long as deep; third joint very thin, more
than twice as long as the second, with the longest terminal sete extremely long, longer than the two
distal joints and half of the proximal joint combined. — Antennze slender but somewhat short as
compared with the antennule (fig. 3c); third joint feebly thickened; fourth joint about twice as long
as the penultimate; terminal sete long, yet conspicuously less than half as long as those of the
antennulee.

Chelipeds slender (fig. 3c). Posterior process on the basal joint moderately short; the distance
between its hind margin and the front lower end of second thoracic segment about half as long as
the basal joint. Carpus considerably longer than the basal joint, almost three times as long as deep.
Chela (fig. 3d) slightly longer than the carpus, almost four times as long as broad; movable finger
neatly half as long again as the front margin of the hand; fixed finger. much broader than the
movable with a few low, obtuse teeth towards the end of the incisive margin.

Thoracic segments somewhat reminding of those of 7: zrregularis, increasing in length and

decreasing in breadth from second to fifth, decreasing in length and increasing in breadth from fifth

CRUSTACEA MALACOSTRACA. II. 43

to seventh segment (fig. 3a). Second segment about twice as broad as long, with the lateral margins
distinctly convex and besides converging from somewhat behind the anterior to the posterior end;
the segment is below and a little behind the front end produced in a very strong, oblique-triangular,
acute process directed downwards and much forwards (fig. 3c). Third segment about half as long
again as the second, broadest not much behind the anterior margin, but the lateral angles somewhat
rounded, and from these angles the margins converge considerably to the hind margin; fourth seg-
ment nearly as the third, but the rounded lateral angles are nearer to the middle of the segment;
fifth segment as long as broad, with the lateral margins nearly regularly convex. The two posterior
segments increase almost gradually in breadth to somewhat behind the middle and the posterior part
of their lateral margins is convex, thus converging near the hind margin, which is longer than the
front margin of the same segment. — Thoracic legs slender. Second pair long (fig. 3c); fourth joint
with a long seta from the anterior distal angle; fifth joint with two long sete from the corresponding
angle; sixth joint only somewhat longer than the fifth, with the setee somewhat short; seventh joint
_ with claw scarcely as long as fifth joint. Third pair somewhat shorter than the second; fifth joint
with a long seta from the anterior distal angle; sixth joint as long as the fifth plus half of the
fourth, with its distal anterior seta extremely long; seventh joint with claw less than half as long
as sixth joint. Fourth pair in the main as the third. Three posterior pairs subsimilar, moderately
long, slender (fig. 3e); second joint more than four times as long as broad; fourth joint not expanded,
without spines, fifth joint (fig. 3f) with a small spine on the outer side of the end, while the joint
is distally on the anterior side produced into a peculiar, short, broad, subtriangular, acute process
directed forwards; sixth joint moderately strong, scarcely widened towards the end, a little longer than
fifth joint and with a small spine on the anterior side a little before the end; seventh joint with claw
distinctly less than half as long as sixth joint.

Abdomen a little longer than the two posterior thoracic segments combined and as broad as
the second segment. — Uropods moderately short (fig. 3g); endopod two-jointed, with first joint con-
spicuously longer than the second; exopod scarcely reaching the middle of second joint of the endopod,
without any perceptible division into two joints.

Length 2.45™™.

Subadult Male. It differs from the female in having the antennule (fig. 3h) much thicker;
first joint is not four times as long as deep and with nearly the same depth from base to end; the
two other joints combined as long as first joint; second joint is proportionately thick, though some-
what longer than deep; third joint is conspicuously thicker than in the female and with the proximal
third a little thickened below.

Remarks. TZ. mucronatus is especially distinguished by the long antennule with the third
joint very long and in the female extremely thin, by the large ventral process on second thoracic seg-
ment, by the long setee on some joints of the anterior pairs of thoracic legs, and by the peculiar pro-
cess on fifth joint of the posterior pairs; furthermore the thoracic segments, seen from above, differ

markedly from most other species.

6*

44 CRUSTACEA MALACOSTRACA. II.

Occurrence. It was taken by the “Ingolf? at three stations in the cold area and in very con-
siderable depths.
North-East of Iceland: St. 120: Lat. 67° 29' N., Long. 11°32’ W., 885 fm., temp. + 1.0°; 10 spec.
— - _ St. 119: Lat. 67°53' N., Long. 10°19’ W., 1or0 fm., temp. + 1.0°; I spec.
South of Jan Mayen: St.117: Lat. 69°13’ N., Long. 8°23’ W., 1003 fm. temp. + I.0; I spec.

26. Typhlotanais eximius n. sp. Re a
(Pl. IV, figs. 4a—4¢g.)

Female (without marsupium). The body of a somewhat contracted, not fullgrown specimen
(fig. 4a) robust, somewhat less than four times as long as broad. — Carapace in the first-named
specimen as long as the three following segments combined, in the second specimen (fig. 4b) somewhat
longer than the two anterior segments combined; it is a little broader than long, the lateral margins
posteriorly convex and then converging nearly evenly forwards to the anterior, somewhat produced
angle; the front margin nearly half as long as the breadth of the carapace and the rostral process
moderately large, acute.

Antennule long, as long as the carapace, second segment and half or almost the whole third
segment combined. First joint (fig.4b) considerably longer than the two other joints combined, about
four and a half times as long as deep, and, seen from the side or from above, tapering considerably
from somewhat from the base to the end. Second joint distinctly more than half as long as the third,
not three times as long as deep; longest terminal seta almost as long as first and second joints
combined. — Antennze somewhat long; third joint somewhat thickened; fourth joint twice as long as
the penultimate; terminal setee very long, though somewhat shorter than those of the antennule.

Chelipeds (fig. 4b) long and very slender, excepting the basal joint which is somewhat thick,
with the posterior protuberance thick, short, broadly rounded behind and reaching to near the front
lower angle of second thoracic segment. Carpus more than half as long again as the basal joint,
four times as long as deep and somewhat curved, with the lower margin conspicuously concave.
Chela as long as the carpus and nearly more than six times as long as broad, with the hand very
elongate, only somewhat less than twice as long as the movable finger, which is slightly thinner than
the fixed finger.

Thoracic segments short in proportion to their breadth; the three anterior segments together
as long as fifth and sixth segments combined; the second segment is about half as long as the third
and the fourth is somewhat longer than the fifth, which is slightly longer than the sixth. The lateral
margins of third and fourth segments feebly convex before the middle, of the three posterior segments
a little convex or subangular rather near their posterior end. Second segment below with a moderately
small, curved, acute process projecting near the front end, directed downwards and much forwards. —
Thoracic legs slender. Second pair (fig. 4b) long; fifth joint with the distal.anterior seta moderately
short, sixth joint somewhat longer than the fifth and considerably longer than seventh with claw.
Third pair not much shorter than second; fourth and fifth joints with the seta on the distal anterior

angle somewhat long; sixth joint with the distal anterior seta somewhat long; seventh joint with

CRUSTACEA MALACOSTRACA. II. 45

claw less than half as long as sixth joint. Sixth and seventh pairs (fig. 4c) much shorter than the
anterior pairs; second joint about three and a half times as long as broad; fourth and fifth joints very
moderately thickened towards their end, sixth joint somewhat long and slender, twice as long as
seventh joint with claw.

Abdomen proportionately long, in the contracted specimen (fig. 4a) even slightly shorter than
the three posterior thoracic segments combined. — Uropods (figs. 4a and 4d) long; endopod two-
jointed, with first joint somewhat longer than second; exopod slightly shorter than the endopod, two-
jointed, with the proximal joint about half as long as the distal.

Length of the largest specimen 1.50™", of the contracted specimen (fig. 4a) 1.19™".

Immature Male. A single specimen, only 1.0™ long, is at hand, and its most important
parts are rendered in figs. 4e—4g. Some of the differences between this specimen and the two above-
described females are due to sex, other differences probably to age. The antennule are considerably
thicker than in the female; first joint, which is as long as the two other joints combined, is only
three times as long as deep and tapers slightly towards the end; second joint is conspicuously less
than twice as long as deep, third joint more than twice as long as the second. — Antenne with fourth
joint distinctly less than twice as long as the penultimate joint. — The chela is slightly thicker than
in the female with the hand conspicuously less elongate in proportion to the length of the movable
finger. — The anterior pairs of legs are a little thicker in proportion to length than in the larger
female. Uropods with the rami equal in length.

Remarks. TZ. eximius is easily distinguished from all other species by its very slender chel-
ipeds with the very elongate chelz and the hand very long in proportion to the fingers. In all other
features it is allied to 7: penzcillatus G.O.S., differing only in various minor particulars, among which
the most conspicuous is the fact, that in 7. pemzcillatus the exopod of the uropods (fig. 5c) reaches
scarcely or slightly beyond the middle of the second joint of the endopod.

Occurrence. Taken by the “Ingolf” at a single station.

South-West of Iceland: St. 78: Lat. 60°37'N., Long. 27°52’ W., 799 fm., temp. 4.5°; 3 spec.

27. Typhlotanais penicillatus G. O. Sars.
(Pl. IV, figs. 5a—5d.)
1881. Zyphlotanais penicillatus G. O. Sars, Arch. for Math. og Naturv. B. 7, p. 39.
! 1806. _ — -- Account Crust. Norway, Vol. II, p. 25, Pl. XI, fig. 3.

The “Ingolf’ specimens agree well with Sars’ description and figures of this species excepting
that the sete on the chelipeds are considerably longer, but that may be due to an accident or a slight
error. Furthermore Sars stated that the exopod of the uropods is one-jointed, while it is two-jointed
in my specimens, but the articulation between the two joints is not always really distinct.

T. penicillatus is closely allied to 7: eximius n. sp. but differs especially in having the cheli-
peds shorter and much thicker and in having the exopod of the uropods (fig. 5c) conspicuously
shorter than the endopod; furthermore the antennule, antenne and anterior thoracic legs (fig. 5a) are

in my largest specimens conspicuously shorter and thicker than in 7: exdmius; third pair of legs with

46 CRUSTACEA MALACOSTRACA, II.

a small spine on the posterior side and near the end of sixth joint. It agrees above all with 7: eximius
in having the carapace considerably longer than the two anterior thoracic segments combined, in
having the antennule and antenne terminating in extremely long sete and in possessing an acute
process (on fig. 5a overlapped and therefore rendered by dotted lines) on the ventral side of second
thoracic segment. — The chelipeds are characteristic; the carpus is considerably longer than the basal
joint and about two and a half times as long as deep; the chela is a little or somewhat longer than
the carpus, between three and a half and four times as long as broad, and the movable finger is only
a little shorter than the anterior margin of the hand. ss

Marsupium is not found in any of my specimens. Somewhat young specimens are on the
whole more clumsy, with the appendages shorter and more robust than in nearly fullgrown spec-
imens. The largest specimen at hand is 1.56™. — In a specimen measuring 1.27™™ the antennule
(fig. 5d) are considerably thicker, shaped nearly as in the young male of Z: eximius, and therefore I
consider this specimen to be an immature male.

Occurrence. TZ, penicillatus was brought home by the “Ingolf” from two stations.

Denmark Strait: St.go: Lat. 64°45’ N., Long. 29°06’ W., 568 fm., temp. 4.4°; I spec.

South-West of Iceland: St. 78: Lat. 60°37’ N., Long. 27°52’ W., 799 fm., temp. 4.5°; 15 spec.

Distribution. Sars established this fine species on two specimens taken by him “at Saue-

sund, west coast of Norway, from depths of 50 to 100 fathoms”.

28. Typhlotanais inermis n. sp.
(Pl. IV, figs. 6a—6g.)

Female (without marsupium). Moderately robust, about five and a half times as long as
broad. — Carapace (figs. 6a and 6b) about as long as the two following segments combined, slightly
longer than broad, with the lateral margins slightly converging from the base to beyond the middle
and then more curved to the antero-lateral angles which are somewhat removed from the outer base
of the antennulz; the distance between these angles is more than two-thirds as long as the breadth
of the carapace in front of its posterior margin, and from each angle the anterior margin is directed
inwards and somewhat forwards to the acute median angle, each half of this front margin being
slightly concave; the result is, that the carapace is pentagonal.

Antennulz nearly as long as carapace and half of the next segment combined, very slender.
First joint is, seen from the side, between four and five times as long as deep and tapers considerably
from somewhat beyond the base to the end (fig.6a); seen from above (fig. 6b) this joint has the basal
fifth very broad, the outer margin angular at the end of that fifth, and from this angle the joint,
which is distinctly less than three times as long as broad, tapers strongly to the distal end; it is
somewhat longer than the two other joints combined. Second joint slender; third joint more than
twice as long as the second, very slender, with the terminal sete very long, the longest being some-
what longer than the two proximal joints combined. — Antenne of moderate length, rather slender;
second joint somewhat expanded above, third scarcely thickened, fourth somewhat less than twice as
long as the penultimate joint; some of the terminal sete about half as long as the long sete of the

antennule.

CRUSTACEA MALACOSTRACA. II. 47

Chelipeds (fig. 6c) moderately robust. Basal joint with the posterior protuberance somewhat
short, posteriorly rounded; its hind margin rather distant from the lower front angle of second thoracic
segment. Carpus a little longer than the basal joint and a little more than twice as long as deep,
with both margins feebly convex. Chela (fig.6d) as long as the carpus, a little more than three times
as long as broad; movable finger somewhat longer than the anterior margin of the hand; fixed finger
much broader than the movable, with about three teeth along the distal part of the incisive margin
and the last tooth rectangular and much larger than the two other teeth.

Thoracic segments (fig. 6a) differ slightly in breadth; all are subrectangular with the angles
a little rounded; the major part of their lateral margins parallel or feebly convex. Second segment
conspicuously less than half as long as the third, without any process below. The segments increase
in length from the second to the fifth and decrease from the fifth to the seventh, but the fourth seg-
ment is slightly longer than the third and slightly shorter than the fifth. — The anterior legs moder-
ately long and slender. Second pair (fig. 6c) with a very long seta both from the anterior and the
posterior distal angle of fifth joint; sixth joint about as long as fifth joint plus half of the fourth,
with the distal setee short; seventh joint with claw slightly longer than sixth joint. Third pair some-
what shorter than second; fourth joint with a long seta from the distal posterior angle, fifth joint with
a very long seta both from the anterior and the posterior distal angle; sixth joint somewhat longer
than fifth, with short sete; seventh joint with claw distinctly more than half as long as sixth joint.
Sixth and seventh pairs (fig.6e) with the second joint somewhat widened, two and a half times as long
as broad; fourth joint feebly tapering and with a short spine at the distal anterior angle (fig. 6f);
fifth joint moderately broad, slightly broader towards the end and with a small, low, glabrous pro-
tuberance just before the end of the anterior margin and a minute spine at the end; sixth joint only
a little longer than the fifth, very moderately slender, with a spine near the distal anterior angle;
seventh joint with claw about half as long as sixth joint.

Abdomen somewhat longer than and as broad as the two preceding segments combined. —
Uropods somewhat short; endopod (fig. 6g) two-jointed, with first joint slightly longer than the
second; exopod slightly or a little longer than the proximal joint of the endopod.

Length of females without marsupium 2.3™"; females with marsupium unknown.

Immature Male. Differs from the female in the antennulz, which are thickened as in the
young male of 7: mucronatus.

Remarks. This species is allied to 7: Aenicillatus, but it is somewhat larger, a little more
slender and differs in the shape of the carapace, in having seventh joint with claw of second and third
pairs of legs much longer in proportion to the sixth joint, in possessing long or very long setz on
fifth joint of these legs, in having the exopod of the uropods considerably shorter and unjointed,
and no ventral process on second thoracic segment. TZ: penicillatus is a warm water species, while
7. inermis is known only from the cold area, with the temperature below zero.

Occurrence, This species has been taken by the “Ingolf’ at four stations.

North of the Feeroes: St. 141: Lat. 63°22'N., Long. 6°58’ W., 679 fm., temp. + 0.6°; 1 spec.

Ses — St. 138: Tat. 63° 26' N., Long. 7°56’ W., 471 fm., temp. -+ 0.6°; I spec.

48 CRUSTACEA MALACOSTRACA. II.

North of the Feeroes: St. 139: Lat. 63°36'N., Long. 7°30' W., 702 fm., temp. + 0.6°; 10 spec.
East of Iceland: St. 102: Lat. 66°23’ N., Long. 15°52’ W., 750 fm., temp. + 0.9°; 6 spec.

29. Typhlotanais variabilis n. sp.
(Pl. IV, figs. 7a—7d; Pl. V, figs. 2a—2c.)

Female. Moderately slender (fig. 7a), about six times as long as broad. — Carapace somewhat or
considerably shorter than the two following segments combined, somewhat longer than broad, with
the lateral margins convex posteriorly and their anterior two-thirds converging to the anterior angles;
the anterior end slightly more than half as broad as the carapace somewhat before its posterior mar-
gin; the rostral process well developed, acute.

Antennule scarcely as long as the carapace and half of the next segment combined, rather
slender (fig. 2a). First joint from a little more than four to five times as long as deep and, seen from
the side or from above, tapering regularly from near the base to the end, considerably longer than
the two other joints combined; second joint twice (fig. 2b) or conspicuously more than twice (fig. 2a)
as long as deep and more than half as long as third joint; longest terminal seta slightly or somewhat
longer than the two distal joints combined. — Antennze of normal size; third joint scarcely thickened;
fourth joint slightly or distinctly more than twice as long as the penultimate; terminal sete conspic-
uously shorter than those of the antennule.

Chelipeds (fig. 2a) somewhat long, moderately slender. Basal joint with the posterior pro-
tuberance of moderate length; the distance between its hind margin and the front lower end of se-
cond thoracic segment about half as long as the joint. Carpus half as long again as the basal joint,
three times or a little more than three times as long as deep, with the lower margin nearly straight.
Chela somewhat longer than the carpus, not fully four times as long as broad; movable finger a little
longer than the anterior margin of the hand; fixed finger much broader than the movable, with a
feeble tooth near the end of the incisive margin.

Thoracic segments (fig. 7a) increase feebly in breadth from second to seventh. Second seg-
ment with the lateral margins feebly converging from the front to the posterior end. Third and fourth
segments broadest somewhat before the middle, but the lateral angles at the broadest place of the
segments are somewhat rounded and from thence the margins converge moderately to the hind mar-
gin. Fifth and sixth segments broadest somewhat from the posterior margin and their lateral margins
are somewhat convex; seventh segment with the anterior half of the lateral margins convex, the po-
sterior half straight. Second segment without any ventral process in the single female with marsupium
and in a female of the same size with the ventral side of the anterior segments flat; in all other
specimens the ventral side of the anterior segments is convex as in the subadult male (fig. 2c) and
second segment has a conspicuous, acute ventral process projecting downwards and much forwards
from the anterior part of the segment. — Thoracic legs of moderate length and rather slender. Se-
cond pair (fig. 2a) with the distal setee on fourth and fifth joints somewhat short or moderately long;
sixth joint as long as the fifth plus half of the fourth, with the distal setae somewhat short; seventh

joint with claw somewhat shorter than sixth joint. Third pair somewhat or rather considerably shorter

CRUSTACEA MALACOSTRACA. II. 49

than second pair, because fourth, fifth and sixth joints are conspicuously shorter than in the last-
named pair; the distal anterior setee on fourth, fifth and sixth joints somewhat long, and in one spec-
imen the distal posterior seta on fourth joint was very long; seventh joint with claw distinctly more
than half as long as sixth joint. Three posterior pairs of legs (fig. 7b) with second joint about three
times as long as broad; fourth joint (fig. 7c) with two distal short spines on the anterior side; fifth
joint somewhat thick, with a rounded expansion on almost the distal half of the anterior margin and
a few tiny spinules on that expansion; sixth joint about as long as the fifth plus half of the fourth,
twice as long as seventh joint with claw.

Abdomen not fully as long as the two preceding segments combined, but a little broader than
the last thoracic segment. — Uropods somewhat long and slender (fig. 7d); endopod with the proximal
joint a little or slightly longer than the distal; exopod distinctly longer and more slender than the
endopod, two-jointed, and the distal joint almost twice as long as the proximal.

Length of a female with marsupium and of the largest female without marsupium 2.4™".

Subadult Male. The antennule are thick (fig. 2c); first joint only a little more than three
times as long as deep and tapers a little towards the end; second joint about as long as deep; third
joint with the proximal half somewhat thickened below. Ventral process on second thoracic segment
well developed (fig. 2c). Abdomen a little longer than the two preceding segments combined.

Remarks. 7: variadilis is easily distinguished from all other species of Zyphlotanais men-
tioned here or found at Norway by having the exopod of the uropods distinctly longer than the
endopod. In various features it is allied to 7: penzczllatus.

As to the variation in presence or absence of a ventral process on second thoracic segment I
refer to the statements on p. 7.

Occurrence. TZ: variabilis has been taken by the “Ingolf at three stations, all in the cold
deep-sea area.

North of the Feroes: St. 139: Lat. 63° 36'N., Long. 7° 30’ W., 702 fm., temp. + 0.6°; 3 spec.

East of Iceland: St. 105: Lat. 65° 34’N., Long. 7° 31' W., 762 fm., temp. + 0.8°; 3 spec.

— eS St. 102: Lat. 66° 23'N., Long. 10° 26’ W., 750 fm., temp. -+ 0.9°; 2 spec.

(One of these speciinens, represented in fig. 2a, has a minute parasitic

Copepod (/) fixed on the base of second left leg.)

30. Typhlotanais trispinosus n. sp.
(Pl. V, figs. 4a—qf)

Female (without marsupium). Body slender, nearly seven and a half times as long as broad
(fig. 4a). — Carapace about as long as the two following segments combined, somewhat longer than
broad; its lateral margins converge slightly from near the base to somewhat from the front end where
they are more curved; the front end is a little more than half as broad as the carapace near its base,
and the rostral process is well developed, somewhat narrow, acute.

Antennule (fig. 4b) nearly or scarcely as long as the carapace, moderately slender. First joint

about three and a half times as long as deep, somewhat tapering and somewhat longer than the two
The Ingolf-Expedition. III. 3. 7

50 CRUSTACEA MALACOSTRACA. IT.

other joints combined; second joint considerably longer than deep; third joint conspicuously more
than twice as long as the second, with the longest terminal seta about as long as the joint. — An-
tenne rather long; second and third joints (fig. 4c) very thick, third joint on the lower side with three
strong, spiniform and nearly hook-shaped processes directed much backwards; second joint with a
similar process a little behind the front lower angle and sometimes besides a minute, acute denticle
behind the hook; fourth joint is distinctly more than twice as long as the penultimate joint, and the
terminal setee nearly as long as those of the antennule.

Chelipeds (fig. 4b) somewhat long and strong. Basal joint with the “posterior protuberance
somewhat long and rounded behind; the distance between its hind margin and the lower front end of
second thoracic segment distinctly more than one-third of the length of the joint. Carpus much
longer than the basal joint and nearly three times as long as deep. Chela as long as the carpus and
little more than three times as long as broad; movable finger nearly as long as the front margin of
the hand; fixed finger inconsiderably thicker than the movable, with low teeth towards the end of
the incisive margin.

Thoracic segments (fig. 4a), taken together, with the lateral margins parallel excepting in front
and behind, as the margins of second segment converge somewhat from near the front end to the hind
margin, while those of seventh segment converge in the opposite direction. Second segment some-
what or considerably shorter than the third, below a little behind the front angle with a somewhat
small, subacute process directed mainly forwards (fig. 4b). Third, fourth and sixth segments nearly
equal in length, nearly as long as broad and only a little shorter than fifth segment. — Thoracic legs
somewhat short. Second pair (figs. 4b and 4d) with fourth joint distinctly, longer than the fifth and
without setze; seta on the anterior angle of fifth joint somewhat short; sixth joint a little shorter than
fifth and fourth joints combined, and the seta on the anterior side stiff and only a little longer than
the diameter of the joint; seventh joint with claw about as long as fourth joint; the third joint on
the posterior side with an extremely long, strong seta reaching the end of fifth joint. Third pair with
the seta on third joint proportionately still longer than that on second pair; fourth, fifth and sixth
joints conspicuously shorter than in second pair, but preserving the same proportion as to length and
similarity as to sete; seventh joint with claw considerably less than half as long as sixth joint. Fourth
pair with the same enormous seta on third joint. Seventh pair (fig. 4e) is rather robust; second joint
expanded, only about twice as long as broad; third joint scarcely distinguishable; fourth and fifth
joints much widened, with curved rows of very fine spines on the outer side and on the convex
margin; sixth joint is not much longer than the fifth, with some five minute incisions along the
longest margin and at the end with a long seta and two strong, moderately long spines pectinate
along the concave margin; seventh joint very short and the claw minute. Sixth pair of legs are a
little, and fifth pair somewhat, more slender than seventh pair, with seventh joint conspicpously longer
and thinner, while fourth and fifth joints are adorned in the main as in seventh pair.

Abdomen somewhat shorter than the two preceding segments combined. — Uropods short,
both rami one-jointed and the endopod somewhat longer than the exopod.

Length 2™™,

Remarks. C. ¢rispinosus in closely allied to 7. tenuicornis G.O.S. Both these species agree

CRUSTACEA MALACOSTRACA. II. 51

with each other and differ from all other species known by two very peculiar characters: the lower
side of second and third joints of the antennz is furnished with strong, hook-shaped processes, and
the third joint of the three anterior pairs of thoracic legs bears an extremely long seta. But before
mentioning the differences between 7: ¢risfimosus and T. tenuicornis 1 may write some remarks on
Sars’ description and figures of the last-named species. I have studied some co-types presented to our
Museum by Sars, and have drawn three analytical figures (Pl. V, figs. 3a—3c) for comparison with
my figures of 7: ¢rispinosus.

Sars described and figured the antennze of 7: ¢enuicornis as having two strong hooks on third
joint and none on second joint, but in his co-types I find two strong hooks on each of these joints
(fig. 3a). Sars’ figure of the second leg is not quite correct; I have found (fig. 3b) the very long seta
on the posterior angle of fourth joint, but no seta on the posterior angle of fifth joint; it does not
seem probable that the ‘last-named seta exists though it has been drawn by Sars, but we have both
figured a moderately short and thin and a rather long, strong seta on the anterior angle of that
joint; finally, the seta on the anterior margin of sixth joint is very strong, nearly spiniform, and, as
also drawn by Sars, more than half as long as the joint, and seventh joint with claw is only as long
as fifth joint, being too long in Sars’ figure. Third pair of legs (fig. 3c) nearly as drawn by Sars,
excepting that fifth joint has a minute denticle — as in 7 /rispinosus — and no seta at the posterior
distal angle, furthermore fourth joint has only a moderately long seta on the posterior angle. The
three posterior pairs of legs have their fourth and fifth joints adorned with rows of very fine spines
in the main as in 7. ¢rispisosus.

T. trispinosus differs from 7: tenutcornis especially in the armature of second and third antennal
joints and in the feebler development of sete on fourth to sixth joints of second pair of legs. The
difference in the armature of the antennal joints is easily seen from my descriptions and figures of
these parts of both species. A comparison of my fig. 3b with fig. 4c shows that the two long sete
found on the posterior angle of fourth joint and the anterior angle of fifth joint of second legs in
I. tenuicornis are wanting in 7. ¢rispimosus, furthermore that the stiff seta on sixth joint is propor-
tionately twice as long in the former as in the latter species. Finally it may be pointed out that an-
tennulz, antenna, chelipeds and thoracic legs are thicker in proportion to length in 7. frispinosus
than in 7. ¢enwicornis. The last-named species is known only from the west coast of Norway, from
depths ranging between 60 and 120 fathoms, and from Skager Rak, N.N.E. of the lighthouse of the
Skaw, 125 fm. (H. J. Hansen).

Occurrence. TZ. ¢rispinosus has been taken by the “Ingolf” at a single station.

Davis Strait: St. 36: Lat. 61°50’ N., Long. 56° 21’ W., 1435 fm., temp. 1.5°; 17 spec.

31. Typhlotanais profundus n. sp.
(Pl. V, figs. 5a—5se.)
Female (without marsupium). Body moderately robust, not fully six times as long as broad
(fig. 5a). — Carapace a little longer than the two following segments combined and about as long
as broad; the lateral margins conspicuously convex and the anterior end slightly more than half as

broad as the carapace somewhat before the posterior margin; the frontal process moderately large.
y

52 CRUSTACEA MALACOSTRACA. II.

Antennulz slightly longer than the carapace. First joint is even more than half as long again
as the two other joints combined, seen from the side (fig. 5c) almost four times as long as deep and
tapering much from near the base to the end; seen from above (fig. 5b) this joint is somewhat less
than three times as long as broad and the distal half is much narrower than the proximal, which
has the outer margin a little angular somewhat from the base and the limit between the proximal
and the distal part incised and furnished with an outstanding seta. Second joint is, seen from the
side, more than twice as long as deep; third joint is somewhat less than twice as long as the second,
and its longest terminal setee about as long as the first joint. — Antenne (fig. 5c) of normal length;
third joint is distinctly thickened, fourth joint slightly more than twice as long as the penultimate;
terminal sete only a little shorter than those of the antennule.

Chelipeds (fig. 5e) moderately stout. Basal joint somewhat long, with the posterior protuberance
of middle length, rounded behind and reaching to near the front margin of second segment; carpus
considerably longer than the basal joint and somewhat less than three times as long as deep. Chela
slightly longer than the carpus, about three and a half times as long as broad and with the posterior
margin considerably concave; movable finger as long as the anterior margin of the hand and a little
narrower than the fixed finger.

Thoracic segments (fig. 5a) show a little difference in breadth. Second segment somewhat
more than half as long as the third, anteriorly as broad as, or a little narrower than, the carapace,
with the lateral margins somewhat converging to the posterior margin and below a moderately small
ventral process curved forwards and originating near the front end. Third, fourth and sixth segments
with their lateral margins nearly parallel and the corners rectangular; fifth and sixth segments with
the lateral margins diverging a little from the anterior to the posterior end; third segment slightly
shorter than the fourth, which is as long as the sixth, a little shorter than the fifth and half as broad
again as long. — Thoracic legs of moderate length and thickness. Second pair (fig. 5e) with some-
what short sete; sixth joint long, even a little longer than fifth plus half of the fourth; seventh joint
with claw slightly longer than fifth joint. Third pair with fourth to sixth joint conspicuously shorter
than in second pair; sixth joint only a little shorter than fourth and fifth joints combined, twice or
more than twice as long as seventh joint with claw; seta somewhat short. Three posterior pairs
nearly as in Z. cneguipes (comp. fig. ga); second joint about two and a half times as long as broad;
fourth joint with a minute tooth; fifth joint a little expanded; sixth joint somewhat slender and almost
as long as the two preceding joints combined; seventh joint with claw of middle length.

Abdomen not broader than the posterior part of the thorax but somewhat longer than its two
‘posterior segments combined. — Uropods short (fig. 5d); endopod two-jointed, with the proximal joint
a little longer than the distal; the exopod reaches beyond the middle of second joint of the endopod
and seems to be one-jointed.

Length of the largest specimen 1.76™",

Subadult Male (fig. 5e). Antennule about as long as the carapace ‘and half of the next
segment combined, thick; first joint somewhat longer than the two other joints combined, seen from

the side somewhat less than three times as long as deep and slightly tapering towards the end;

CRUSTACEA MALACOSTRACA. II. 53

second joint about as deep as long; third joint twice as long as second, with the most proximal part
feebly thickened below.

Remarks. This species is allied to 7: fimmarchicus G.O.S. and 7. mixtus un. sp., but differs
considerably in the antennule, which have much longer terminal setee and the first joint in the female
very differently shaped; furthermore the exopod of the uropods seems to be one-jointed in 7: pro-
Jundus, while it is distinctly two-jointed in the two other species.

Occurrence. TZ. profundus has been taken by the “Ingolf” at a single station.

South of the Davis Strait: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870 fm., temp. 1.3°; 4 spec.

32. Typhlotanais spinicauda n. sp.
(Pl. V, figs. 6a—6h.)

Female (without marsupium). Body somewhat slender, seven times as long as broad. —
Carapace (fig. 6a) somewhat longer than the two following segments combined and considerably longer
than broad, seen from above subcylindrical excepting its anterior third, which has the lateral margins
converging forwards and distinctly convex; the anterior end almost two-thirds as broad as the base,
with the frontal process of moderate size, acute.

Antennule (figs. 6a and 6c) conspicuously shorter than the carapace, somewhat robust. First
joint more than half as long again as the two other joints combined, seen from the side little more
than three times as long as deep and tapering very moderately; seen from above not quite two and
a half times as long as broad and tapering regularly from base to end. Second joint short and slightly
longer than deep; third joint nearly three times as long as the second, and its terminal sete seem to
be a good deal shorter than the joint. — Antenne of normal length; third joint not thickened; fourth
joint twice as long as the penultimate; terminal setze considerably longer than those of the antennule.

Chelipeds (figs. 6b and 6d) of moderate length and thickness. Basal joint with the proximal
protuberance scarcely as long as deep and its posterior margin not far from the front lower angle of
second segment; carpus much longer than the basal joint, a little more than two and a half times as
long as deep. Chela small, considerably shorter than the carpus, a little more than three times as
long as broad; movable finger as long as the anterior margin of the hand; fixed finger near the base
conspicuously broader than the movable.

Thoracic segments, seen from above, cylindrical with parallel margins. Second segment half
as long as the third, with a conspicuous, oblong-triangular, acute, horizontal ventral process originating
somewhat behind the front end of the segment (fig. 6b). Third and fourth segments with their
front lateral angles produced in small, acute triangles only visible from the side (fig. 6b). — Thoracic
legs short. Second pair (fig. 6e) somewhat slender with the sete short; sixth joint as long as the
fifth and half of the fourth combined; seventh joint with claw a little shorter than sixth joint. Third
pair (fig. 6f) considerably shorter and distinctly thicker than the second, with short sete; sixth joint
a little shorter than the two preceding joints combined, seventh joint with claw conspicuously more
than half as long as sixth joint. Sixth pair (fig.6g) with the second joint somewhat expanded, slightly
more than twice as long as broad; fourth and fifth joints rather broad and fourth joint with a distinct,

54 CRUSTACEA MALACOSTRACA. II.

distal marginal tooth; seventh joint proportionately long, together with the short and thin claw slightly
shorter than the sixth joint.

Abdomen at the middle of the hind margin with a short, protruding plate (fig. 6h), and each
angle of the plate produced in a spiniform process; the distance between the end of each process and
the hind margin is slightly longer than the breadth of the plate. — Uropods moderately long; endopod
two-jointed (fig. 6h), with the proximal joint a little longer than the distal and with some minute
spines along its inner margin; exopod a little shorter than the proximal joint of the endopod, two-
jointed, with the joints equal in length.

Length of the single specimen 2.0™.

Remarks. 7. sfinicauda is easily distinguished from all other species by the plate with its
two spines protruding from the end of abdomen; the uropods are also very characteristic. In several
features it is allied to 7: finmarchicus G. O. S.

Occurrence. Taken by the “Ingolf? at a single station.

Davis Strait: St. 28: Lat. 65°14’ N., Long. 55°42’ W., 420 fm., temp. 3.5°; 1 spec.

33. Typhlotanais grandis un. sp.
(Pl. V, figs. 7a—7e.)

Specimen without marsupium, probably an immature Male. Very large aud
somewhat slender, scarcely six and a half times as long as broad, but especially fifth thoracic seg-
ment is a good deal more narrow than carapace or abdomen (fig. 7a). — Carapace large, slightly
longer than the two following segments combined and somewhat longer than broad; the lateral
margins posteriorly convex but their anterior two-thirds converge nearly regularly to the front angles;
the anterior end is a little more than half as broad as the carapace somewhat behind the middle; the
rostral process is broad, somewhate short, acute.

Antennule (fig. 7b) a little shorter than the carapace. First joint slightly longer than the two
other joints combined, slightly more than two and a half times as long as deep and, seen from the
side, scarcely tapering, seen from above distinctly and regularly tapering from base to end. Second
joint a little deeper than long; third joint long, about three times as long as the second and its
proximal fourth distinctly thickened above; terminal setee about as long as third joint. —- Antenne
of normal length and thickness; third joint scarcely expanded; fourth joint a little more than twice
as long as the penultimate joint; terminal sete a little longer than those of the antennule.

Chelipeds (fig. 7b) moderately robust. Basal joint long with the posterior protuberance even
a little longer than deep, rounded behind, but its hind margin is somewhat distant from the front
lower angle of second thoracic segment; carpus as long as the basal joint, only twice as long as deep.
Chela somewhat longer than carpus, three times as long as broad, with the posterior margin straight;
movable finger as long as the front margin of the hand; fixed finger near the base conspicuously
broader than the movable and with a small tooth a little from the end of the incisive margin.

Thoracic segments (fig. 7a) increase much in length and decrease considerably in breadth from

second to fifth segment; sixth segment is slightly longer and a little broader than the fifth, much longer

CRUSTACEA MALACOSTRACA. II. 55

and somewhat narrower than the seventh. Second segment is about half as long as the third and
tapers much in breadth from the anterior to the posterior end; it has a small, oblique ventral process
from the lower front end. Third segment with the lateral margins considerably converging from the
anterior to the posterior angles. Fourth segment with the lateral margins strongly angular consider-
ably before the middle and from these angles converging towards both ends. Fifth segment slightly
longer than broad, and its lateral margins strongly angular somewhat behind the middle; sixth seg-
ment with the lateral margins strongly angular still nearer the posterior margin; seventh segment in-
creases much in breadth from the anterior end to rather near the hind margin. — Thoracic legs
moderately long. Second pair (fig. 7b) with the sete short excepting the seta on the posterior margin
of sixth joint; fourth joint somewhat longer than the fifth and as long as the sixth; seventh joint
with claw only two-thirds as long as sixth joint. Third pair with fourth joint shorter than the fifth,
which is somewhat shorter than the sixth; fourth joint with some minute spines on the posterior
margin, setee on fourth and fifth joints short, distal seta on the anterior side of sixth joint rather long;
seventh joint with claw scarcely half as long as sixth joint. Three posterior pairs of legs moderately
strong (fig. 7c); second joint about two and a half times as long as broad; fourth joint (fig. 7d) with
a row of very short, tooth-shaped, small spines along the distal half of its anterior margin and two
much larger spines before the end; fifth joint with a close row of small tooth-shaped spines along the
major part of the convex front margin, a similar, curved row on the outer side, and a moderately
long, very thick spine at the distal end; sixth joint only a little shorter than the two preceding joints
combined, moderately stout, with a large number of quite minute denticles along the anterior part,
two moderately long and very thick spines near the end and three much longer terminal spines, two
of which with a few strong teeth on the concave margin and the third with a number of denticles
along the major distal part of the corresponding margin; seventh joint with claw somewhat short, on
seventh pair less than half as long as sixth joint, and both joint and claw with some few denticles
on the concave margin.

Abdomen broader than seventh thoracic segment, but scarcely as broad as the second, slightly
longer than seventh segment and half of the sixth combined; its hind margin transverse, feebly an-
gular at the middle. — Uropods (fig. 7e) moderately long, somewhat slender; endopod with the first
joint a little longer than the second; exopod reaches slightly beyond the middle of second joint of the
endopod, two-jointed, with second joint about two and a half times as long as the first.

Length of the single specimen 4.18™™.

Remarks. 7. grandis is much larger than any other species of this genus found by Sars or
the “Ingolf”, but agrees in this respect with three species established by Dollfus (1897) on specimens
taken by the Prince of Monaco. 7: grandis is readily distinguished from the three last-named species
by various characters (comp. Dollfus’ figures) and from all forms seen by me by the peculiar armature
of the posterior pairs of legs. In the shape of the thoracic segments 7. grandis is somewhat similar
to 7: wrregularis, but differs widely in several other features.

Occurrence. Taken by the “Ingolf” at a single station.

South of Iceland: St. 54: Lat. 63°08’ N,, Long. 15° 40’ W., 691 fm., temp. 3.9°; I spec.

56 CRUSTACEA MALACOSTRACA. II.

34. Typhlotanais plebejus n. sp.
(Pl. V, figs. 8a—8¢.)

Female (without marsupium). Body slender, almost eight times as long as broad, seen from above
cylindrical (fig. 8a). — Carapace half as long again as broad and nearly longer than second, third and
half of the fourth segment combined; the posterior halves of the lateral margins parallel, the anterior
halves converging and distinctly convex; the front end somewhat more than half as broad as the
carapace and the rostral process moderately developed, acute. ‘f

Antennulz short, considerably shorter than the carapace. First joint (fig. 8b) somewhat longer
than the two other joints combined, about three times as long as deep and moderately tapering from
somewhat from the base to the end, seen from above nearly regularly tapering and about two and
a half times as long as broad. Second joint slightly longer than deep; third joint about three times
as long as the second, only moderately slender; terminal sete a little shorter than third joint. — An-
tenne somewhat long; third joint conspicuously thickened; fourth joint twice as long as the penul- -
timate; terminal setee somewhat shorter than those of the antennule.

Chelipeds (fig. 8c) rather robust. Basal joint very long, because the posterior protuberance is
very elongate, more than half as long again as deep; carpus slightly longer than the basal joint,
not fully two and a half times as long as deep. Chela somewhat small, somewhat shorter than the
carpus and a little less than three times as long as broad, with the posterior margin conspicuously
concave; movable finger somewhat shorter than the anterior margin of the hand; fixed finger at the
base somewhat broader than the movable, with a low protuberance on the incisive margin a little
from the end.

Thoracic segments all rectangular (fig. 8a), increasing in length from second to fifth and de-
creasing from fifth to seventh; second segment slightly shorter than the third, without ventral process;
fifth segment considerably longer than the fourth and slightly longer than broad. — Thoracic legs
on the whole somewhat short and robust. Second pair (fig.8d) with fourth joint as long as the sixth
joint; all setee short. Third pair (fig. 8e) considerably shorter than second; fifth joint slightly longer
than the fourth and not much shorter than the sixth, which is more than twice as long as seventh
joint with claw; sete short or moderately short. Fifth pair (fig. 8f) with second joint much expanded,
scarcely twice as long as broad; fourth and fifth joints uncommonly broad and short; sixth joint
slender and almost as long as fifth and fourth joints combined; seventh joint somewhat long and thin
with a fine, curved claw. (Sixth and seventh pairs mutilated).

Abdomen almost as long as seventh, sixth and half of fourth thoracic segment combined. —
Uropods somewhat short (fig. 8g); endopod distinctly two-jointed, with the first joint considerably
longer than the second; exopod nearly as long as the proximal joint of the endopod, one-jointed.

Length of the single specimen 3.19™".

Remarks. 7: plebeyus is allied to 7. eguiremis Lilljeborg and 7: assimilis G. O. S., but it is
instantly distinguished from both by shorter chele, by having the exopod of the uropods one-jointed
and especially by the very long posterior protuberance on the basal joint of the chelipeds. By the
last-named character it is’ distinguished from all other species of the genus.

CRUSTACEA MALACOSTRACA. II. 57

Occurrence. Taken by the “Ingolf” at a single station.
South of the Davis Strait: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870 fm., temp. 1.3°; 1 spec.

35. Typhlotanais inequipes n. sp.
(Pl. V, figs. ga—gb; Pl. VI, figs. ra—rc.)

Female (without marsupium). Body slender, a little more than seven times as long as broad,
seen from above nearly cylindrical (fig. 1a). — Carapace as long as or a little shorter than the two
following segments combined, not fully half as long again as broad; its lateral margins are nearly
parallel from the base to near the beginning of their distal third, where they begin to converge more
distinctly; the anterior end is scarcely more than half as broad as the base and the rostral process is
middle-sized, acute.

Antennule considerably shorter than the carapace (fig. 1c), somewhat slender. First joint, seen
from the side, about or not fully three times as long as deep and tapering somewhat irregularly from
somewhat from the base to the end; seen from above the joint (fig. rb) is nearly three times as long
as broad and tapers nearly regularly; the joint is somewhat or considerably longer than the two other
joints combined. Second joint from a little less to a little more than half as long as the third and
at most about twice as long as deep; longest terminal sete distinctly longer than third joint. — An-
tennze of normal length (fig. 1c); third joint somewhat thickened; fourth joint at most half as long
again as the penultimate; termiual setee about as long as those of the antennule.

Chelipeds (fig. 1c) somewhat long but only moderately robust. The basal joint somewhat long,
its posterior process large, a little longer than deep with its rounded hind margin considerably distant
from the front margin of second thoracic segment; carpus considerably longer than the basal joint,
three and a half times as long as deep. Chela a little shorter than the carpus, a little less than four
times as long as broad; movable finger a little shorter than the front margin of the hand; fixed finger
at the base somewhat thicker than the movable.

Thoracic segments with the lateral margins parallel excepting on second and seventh seg-
ments, on which the margins converge feebly respectively from the front angles backwards and from
behind forwards. Second segment about two-thirds as long as the third, without ventral process; fifth
segment a little longer than the fourth or the sixth and scarcely as long as broad. — Thoracic legs
moderately strong. Second pair (fig. 1c) quite peculiar; fourth joint very elongate, about two and a
half times as long as the fifth; sixth joint slightly more than half as long again as the fifth; seventh
joint with claw as long as the fifth; sete short. Third pair normal; fourth and fifth joints subequal
in length; sixth joint about half as long again as the fifth and more than twice as long as the
seventh with claw; the sete moderately short excepting a somewhat long, distal seta from the side
of sixth joint. Three posterior pairs not very characteristic; second joint (fig. ga) about two and a
half times as long as broad; fourth joint with a minute distal tooth; fifth joint slightly broader than
the fourth, with one of the margins somewhat convex but without any distinct armature; sixth joint
moderately or rather slender, almost as long as the two preceding joints combined, with a minute
spine somewhat before the end; seventh joint with claw of middle length.

Abdomen slightly broader than the posterior thoracic segments and scarcely as long as the
The Ingolf-Expedition, III. 3. 8

58 CRUSTACEA MALACOSTRACA. II.

two preceding segments combined. — Uropods somewhat short; endopod (fig. gb) two-jointed, with
the first joint somewhat longer than the second; exopod reaching about the middle of the distal joint
of the endopod, divided by a suture at or slightly beyond the middle and with the proximal part of
its long terminal seta quite unusually thick.

Length 2.15™™.

Remarks. TZ: imequipes is easily distinguished from all other species by the peculiarly
elongate fourth joint of second thoracic legs. Antenne, chelipeds and uropdds afford various other
characters, but the species is on the whole allied to 7: méxtus n. sp.

Occurrence. Taken by the “Ingolf” at a single deep-sea station.

Davis Strait: St. 36: Lat.61° 50’ N., Long. 56°21’ W., 1435 fm., temp. 1.5°; 38 spec.

36. Typhlotanais finmarchicus G. O. Sars.
(Pl. VI, figs. 2a—2b.)

1881. Typhlotanars finmarchicus G. O. Sars, Arch. for Math. og Naturv. B. 7, p. 36.
1896. a) — G. O. Sars, Account Crust. Norway, Vol. II, p. 20; Pl. IX (Female and
adult Male).

In the last-named work Sars has published a description and numerous figures of this species,
which differs from all other forms of the genus, excepting Z: mixtus n. sp.. by some characters.

The antennulee (fig.2a) are shorter than the carapace, their first joint between more than half
as long again and a little less than twice as long as the two other joints combined, about three times
as long as deep; second joint conspicuously longer than deep; third joint more than twice as long as
the second, with the longest terminal seta not fully as long as the joint. Second pair of legs some-
what short; sixth joint only a little longer or even shorter than seventh joint with claw. Third pair
of legs with fourth and fifth joints uncommonly short in proportion to thickness, each being only
about half as long again as broad; seventh joint with claw considerably more than half as long as
sixth joint or only a little shorter than this joint.

Sars’ figure of the carpus of the chelipeds is not correct, as its greatest depth is not situated
at the end of the preceding joint, but much nearer the distal end; the carpus is between two and a
half and two times as long as deep; the movable finger of the chela is a little or slightly shorter
than the anterior margin of the hand. Sars’ figure of the uropod does not agree with the uropods
in my numerous specimens, among which some co-types presented by that author; I have drawn a
normal uropod (fig. 2b) and this figure shows that in the endopod the proximal joint is less than
half as long again as the distal, while in Sars’ figure the proximal joint is about twice as long as the
other: furthermore Sars’ figure shows the proximal joint of the exopod to be almost longer than the
distal, while I always found (fig. 2b) the proximal joint conspicuously shorter than the distal. Finally,
it may be mentioned that the ventral side of second thoracic segment has frequently a rather small
or very small, acute process originating behind the front end of the segment and directed essentially
forwards, but sometimes this process could not be found in specimens where it might be expected. —
As to all other features I refer to Sars; the differences between 7. finmarchicus and T. mixtus are

pointed out below.

CRUSTACEA MALACOSTRACA. II. 59

Occurrence. T. finmarchicus has been taken by the “Ingolf” at three localities.
West Greenland: Mouth of Ameralik Fjord, at Godthaab, 5—70 fm., shells; 16 spec.
— _ Inner end — — = — muddy bottom; rz spec.
Jan Mayen: St. 115: Lat. 70°05’ N., Long. 8°26’ W., 86fm., temp. o.1°; large number of specimens.
Furthermore 7. finmarchicus has been taken at Iceland by various Zoologists and at Jan Mayen
and East Greenland by the second Amdrup Expedition. The localities are given here.
West Iceland: @nundar Fjord, 11—12 fm., ooze and stones with a few algze; 2 spec. Mag. W.
Lundbeck.
East Iceland: Faskrud Fjord, 20—5o0 fm., blue clay; 7 spec. Mag. R. Ho6rring.
-- = Nord Fjord, 40 fm.; 1 spec. Mag. R. Horring.
— — Bakke Fjord, 8—1o0 fm.; black sand; 1 spec. Dr. A. C. Johansen.
Jan Mayen: 50—60 fm. and 55 fm. 17 spec. II¢ Amdrup Exp.
East Greenland: Cape Dalton: Lat. 69° 24.6’ N., ab. Lat. 23!/. W., 9—11 fm.; 11 spec.
; II¢ Amdrup Exp.
— — Turner Sound: Lat. 69°44' N., Long. 23!/.° W., 3fm.; Ispec. - — _
— — Sabine Island: Lat. 74°30' N., Long. 19°45’ W., 3—5 fm.; 23 spec.
II¢ Amdrup Exp.
Distribution. TZ fimmarchicus was previously known from Vads6 in Varanger Fjord (North-
eastern Norway), where it occurred in 30 fathoms (G. O. Sars), and from Northbrook Island, Franz
Joseph Land (Th. Scott). — The list given above shows that it has a wide distribution in the arctic
and subarctic areas, while it is not known from the southern and south-western coasts of Iceland or
from the Feeroes.
It may be mentioned here that from the “Ingolf” Stat. 104: West of Iceland: Lat. 66°23' N.,
Long. 7°25’ W., 957 im. temp. + 1.19, I have 2 specimens (an immature female and an immature
male), of which especially the characteristic female certainly belongs to 7: fimmarchicus, though jud-
ging from their occurrence at that deep-sea station it would have been expected that they belonged
to the closely allied 7. méxtus n. sp. It is very improbable that 7. fwmarchicus, which has been
taken at many localities in depths from 3 to 60 fathoms and never in a depth exceeding 86 fathoms,
may occur in a depth of nearly a thousand fathoms; therefore I do not venture to insert that single
deep-sea station in the list of localities, fearing that some error has been committed in one way or

another, but the statement inexplicable at present is mentioned here.

37. Typhlotanais mixtus n. sp.
(Pl. VI, figs. 3a—3f)
Female. Body slender, about seven times as long as broad, seen from above nearly cylindrical
(fig. 3a). — Carapace somewhat or considerably longer than the two following segments combined,
nearly half as long again as broad; lateral margins parallel to near the beginning of their distal
third, then converging and distinctly convex; the anterior end not quite two-thirds as broad as the

carapace, with the rostral process somewhat long, acute.
g*

60 CRUSTACEA MALACOSTRACA. II.

Antennule (figs. 3a and 3b) somewhat shorter than the carapace. First joint only somewhat
longer than the two other joints combined — thus proportionately a good deal shorter than in 7. fin-
marchicus — seen from the side about three times as long as deep and tapering considerably, seen
from above tapering nearly regularly from near the base to the end. Second joint somewhat longer
than deep, less than half as long as the third; longest terminal sete considerably shorter than third
joint. — Antennz with third joint slightly thickened (fig. 3b); fourth joint not twice as long as the
penultimate; terminal sete almost longer than those of the antennule. =

Chelipeds (fig. 3b) moderately long. Basal joint moderately long; the posterior protuberance a
little longer than deep, and the distance between its hind margin and the front lower angle of second
thoracic segment is more than half as long as the joint; carpus rather slightly longer than the basal
joint, about three times as long as deep — thus less robust than in 7: fimmarchicus. Chela as long
as the carpus, a little more than three times as long as broad; movable finger somewhat or a little
longer than the anterior margin of the hand; fixed finger distinctly broader than the movable, with
a couple of triangular teeth towards the end of the incisive margin.

Thoracic segments (fig. 3a) with their lateral margins subparallel excepting those of second seg-
ment which converge backwards. Second segment about half as long as the third, in females without mar-
supium generally with a moderately small or very small ventral process as in 7: finmarchicus. Fifth
segment slightly longer than the fourth or the sixth and slightly shorter than broad. — Thoracic legs
somewhat short and robust. Second pair (fig. 3 b) with fifth joint a little longer than the fourth and not twice
as long as deep; sixth joint much longer than the fifth, about as long as or a little longer than seventh
joint with claw; sete moderately short. Third pair with fourth and fifth joints short in proportion to
thickness; seventh joint with claw considerably more than half as long as the sixth; distal anterior
seta on sixth joint moderately long. Three posterior pairs nearly as in 7: fimmarchicus; second joint
about two and a half times as long as broad; fourth and fifth joints somewhat broad, each with a
distal small spine; sixth joint about as long as fifth and half of the fourth combined; seventh joint
somewhat long, together with the fine claw nearly as long as the sixth joint.

Abdomen slightly broader than seventh thoracic’ segment and about as long as seventh and
sixth segments combined. — Uropods (fig. 3 f) moderately short; endopod with the proximal joint some-
what longer than the distal; exopod scarcely reaching the middle of the distal joint of the endopod,
with the distal joint a little longer than the proximal.

Length of a female with marsupium 1.94™".

Subadult Male. The antennulz (fig. 3c) considerably thicker than in the female; first joint
about two and a half times as long as deep and tapering a little; second joint conspicuously deeper
than long; third joint a little thickened below towards the base. — Length 1.9™™.

Remarks. 17: mixtus might perhaps be considered a variety of 7. finmarchicus, but according
to my judgment it is a separate species; I have learned by experience that even small characters are
not infrequently of specific value. 7: mixtus differs from T. fimmarchicus in having the first joint af
the antennule conspicuously shorter in proportion to the two other joints combined, in having the
carpus of the chelipeds less deep in proportion to its length and the movable finger of the chela longer

in proportion to the front margin of the hand. — I have been unable to find any difference between

CRUSTACEA MALACOSTRACA. II. 61

the specimens from 1435 fathoms in the warm area and specimens from depths ranging between 495
and 1060 fathoms in the cold area, and must therefore refer them all to the same species.
Occurrence. 7: mixtus has been taken by the “Ingolf” at ten deep-sea stations, with a single
exception in the cold area.
Davis Strait: St. 36: Lat. 61°50’ N., Long. 56°21’ W., 1435 fm., temp. 1.5°; 6 spec.
North of the Feeroes: St. 141: Lat. 63°22’ N., Long. 6°58’ W., 679 fim., temp. + 0.6°; 8 spec.
— - - - St. 139: Lat. 63°36’ N., Long. 7°30’ W., 702 fm., temp. + 0.6°; 8 spec.
East of Iceland: St. 102: Lat. 66°23’ N., Long. 10°26’ W., 750 fm., temp. + 0.9°; 4 spec.
North of Iceland: St. 124: Lat.67°40' N., Long. 15°40’ W., 495 fm., temp. + 0.6°; 1 spec.
—- - — ' $t.125: Lat. 68°08’ N., Long. 16°02’ W., 729 fm., temp. + 0.8°; 6 spec.
North-East of Iceland: St. 120: Lat. 67°29’ N., Long. 11°32’ W., 885 fm., temp. + 1.0°; I spec.
_ Serlwiaas St. 119: Lat. 67°53’ N., Long. 10°19’ W., oro fm., temp. + 1.0°; 17 spec.
South of Jan Mayen: St. 118: Lat. 68°27'N., Long. 8°20' W., 1060 fm., temp. + 1.0°; 4 spec.
— - eee St.117: Lat.69°13’N., Long. 8°23' W., 1003 fm., temp. + 1.0°; 13 spec.

38. Typhlotanais cornutus G. O. Sars.

1879. Paratanais cornutus G.O. Sars, Arch. for Math. og Naturv. B. 4, p. 431.
1885. Typhlotanais — G.O.Sars, Norske Nordhavs-Exp., Crust. I, p. 83, Pl. VII, figs. 29—38.
1896. — — G.O.Sars, Account Crust. Norway, Vol. II, p. 24, Pl. XI, fig. 2.

Sars’ figures and description in his last-named work are on the whole good, but it may be
useful to enumerate a number of features, by the combination of which this species is separated from
any other form.

T. cornutus is thicker than most species, being about four and a half times as long as broad.
The carapace is a little or somewhat shorter than the three following segments combined. Antennulz
moderately slender, scarcely as long as the carapace, with the longest terminal sete decidedly longer
than the two distal joints combined. Chelipeds with carpus and chela equal in length and somewhat
short in proportion to breadth; the movable finger a good deal shorter than the front margin of the
hand. — Second thoracic segment half or less than half as long as third segment, which is conspi-
cuously shorter than the fourth. Second pair of thoracic legs somewhat slender; sixth joint conspi-
cuously longer than the seventh with claw, with its distal posterior seta somewhat long. Second joint
of the posterior pairs of legs moderately thick. — Uropods with both rami two-jointed and the exopod
conspicuously shorter than the endopod.

Among the characters pointed out by Sars that drawn from the well-developed rostrum seems
to me less valuable, and it may be stated here that I have some co-types of Sars presented by him-
self. — In specimens with the ventral side of second thoracic segment convex a moderately small or
somewhat large process projects downwards and much forwards, originating somewhat behind the
front end of the segment.

Occurrence. Taken by the “Ingolf’ at a single station.

Davis Strait: St. 32: Lat. 66°35'N., Long. 56°38’ W., 318 fm., temp. 3.9°; 42 spec.

62 CRUSTACEA MALACOSTRACA. II.

Distribution. According to Sars this species has been taken at Kvalo in the most northern
part of Norway (Lat. 70?/,° N.) “from depths of 60—100 fathoms”, and at a locality “about midway be-
tween Beeren Eiland and Finmark”, from 190 fathoms.

39. Typhlotanais solidus n. sp.
(Pl. VI, figs. 4a—4 f).

Female (without marsupium). Body robust, only a little more than four times as long as
broad (fig. 4 a). — Carapace even longer than the three following segments combined, slightly longer
than broad (fig. 4b); the postero-lateral angles broadly rounded, the major part of the lateral margins
converging to near the front end, where they are rounded; the front end is scarcely half as broad as
the carapace somewhat from its hind margin, and the rostral process is somewhat long, acute.

Antennule scarcely as long as the carapace (fig. 4b), moderately robust. First joint half as
long again as the two other joints combined, three and a half times as long as deep (fig. 4c) and
tapering regularly and somewhat feebly; seen from above (fig.4 b) two and a half times as long as broad
and tapering considerably. Second joint about twice as long as deep; third joint rather short, scarcely
half as long again as the second, its longest terminal sete distinctly longer than the two distal joints
combined. — Antenne (fig. 4c) somewhat long; second and third joints considerably widened above;
fourth joint not quite twice as long as the penultimate; longest terminal seta even slightly longer
than that of the antennulz.

Chelipeds (fig. 4c) rather long but moderately robust. Basal joint with the proximal protuber-
ance large, nearly as long as deep and reaching the front end of second thoracic segment; carpus
long, considerably longer than the basal joint and three times as long as deep. Chela a little longer
than carpus, three and a half times as long as broad; anterior margin of the hand almost half as long
again as the movable finger; fixed finger at the base slightly broader than the movable, with a tooth
near the end of the incisive margin.

Thoracic segments (fig. 4a) increase in length and decrease a little in breadth from second to fifth,
decrease in length and increase perceptibly in breadth from fifth to seventh; the lateral margins are
very convex on second and third segments, moderately convex on the fourth segment, less convex but
more or less distinctly angular towards or near the posterior margin on the three posterior segments.
The three anterior segments combined scarcely longer than fifth and sixth segments together. — An-
terior pairs of legs somewhat slender and moderately long. Second pair (fig. 4d) with fifth joint a
little longer than the fourth and somewhat shorter and thicker than the sixth, which is a little longer
than seventh joint with claw; sete short or wanting. Third pair only a little shorter than second;
sixth joint a little longer than fifth and not fully twice as long as seventh with claw, with the upper
distal setee moderately long. Sixth and seventh pairs (fig. 4e) considerably shorter than the anterior
pairs, somewhat slender; second joint nearly three times as long as broad; fourth and fifth joints a
little thickened, respectively with a single spine and two minute distal spines; sixth joint moderately
slender and nearly as long as fourth and fifth joints combined; seventh joint very short with the claw

minute, both together only about one-third as long as the sixth joint.

CRUSTACEA MALACOSTRACA, II. 63

Abdomen slightly broader than seventh thoracic segment, as long as seventh, sixth and half
of the fifth thoracic segment combined. — Uropods short (fig. 4); endopod rather robust, two-jointed,
with the proximal joint distinctly longer than the distal; exopod nearly as long as the endopod, but
more slender and without any perceptible articulation.

Length of the single specimen 1.85 ™.

Remarks. T. solidus is easily distinguished from the other species by its broad body and the
shape of the thoracic segments; antennule, chelipeds and uropods afford further characters. The ani-
mal is yellow, and its exoskeleton seems to be more solid than in any other species of similar size.
The specimen has the ventral side of the thoracic segments flat, consequently no ventral process on

second segment, and seems to be full-grown.

Occurrence. ‘Taken by the “Ingolf” at a single station.
South-West of Iceland: St. 78: Lat. 60°37’ N., Long. 27°52’ W., 799 fm., temp. 4.5°; I spec.

Agathotanais 1. gen.

Body in the female and subadult male moderately slender, decreasing in breadth from the
middle of the carapace to the base of abdomen, which is narrower than the last thoracic segment.
Carapace about as long as the two following segments combined. No eyes. Antennule in the female
three-jointed, with the first joint longer than the two others combined; in the subadult male the third
joint has a transverse suture. Antenne in the female (Pl. VI, fig. 5c) quite rudimentary, consisting of
a minute joint; in the subadult male (fig. 5n) about as long as the proximal depth of the antennule.

Mandibles (fig. 5d) small, with only the incisive part developed, while a movable lacinia and
the molar process are completely wanting. Maxillule (fig. 5 f) consist of a single slender joint curved
towards both ends; the terminal part has several thick spines and some fine hairs; the palp is only
half as long as the joint, slender and very thin-skinned, with two terminal sete. (Maxille not seen,
rudimentary or wanting.) Maxillipeds (fig. 5 g) considerably reduced; the two proximial joints and the
lobes are completely fused, constituting a circular, vaulted, strongly chitinized plate with’ a median
fissure in its anterior part; the four-jointed palps with the terminal joint slender; the epipods — omit-
ted in the figure — are subtriangular, small, thick plates.

Chelipeds slender. Thoracic legs véry slender; second and third pairs completely similar; claw
on the three posterior pairs very long (fig. 5k). Seventh thoracic segment immovably fused with the
abdomen and all abdominal segments immovably fused, but all seven segments are limited by moder-
ately distinct, though feeble furrows (figs. 5b and 50). Pleopods wanting in the female (fig. 5b); in
the subadult male (fig. 50) they are long, unjointed, slender and somewhat conical and all coalesced,
constituting a kind of pyramid with longitudinal impressions between the pairs; each pleopod ter-
minates in a few very short sete. Uropods rudimentary, each being a small, subtriangular joint with-
out any distinct division (figs. 51 and 5m). ;

The exoskeleton of the animals, excepting the walking legs, has a peculiar aspect and seems

64 CRUSTACEA MALACOSTRACA. IL.

to contain a large quantity of calcium, as it is firm but yet fragile. The walking legs are inserted
in small holes in the firm wall of the segments.

Remarks. This genus, founded on some specimens of a single species, is the most aberrant
type of the family hitherto discovered. The three most interesting features are: the rudimentary an-
tennze, the fusion of the last thoracic segment and all abdominal segments in a single portion with
feeble furrows indicating the limits between the seven segments, finally the coalescence of all five
pairs of long, unjointed pleopods in the subadult male.

In the number of joints in the antennule the genus shows affinity to the preceding genera
Paratanats and Typhlotanais, while the similarity of second pair of legs with third pair resembles the
features in Leptognathia and Cryptocope; the reduced mandibles are somewhat similar to those in

Tanaopsts- 4

40. Agathotanais Ingolfi n. sp.
(Pl. VI, figs. 5a—50.)

Female (without marsupium). Body about six and a half times as long as broad. — Cara-
pace (fig. 5a) about as long as the two following segments combined, somewhat longer than broad,
seen from above ovate, with the lateral margins considerably convex to near the front end which is a
little less than half as broad as the base of the carapace and considerably less than half as broad
as the carapace a little behind the middle; frontal process somewhat short and obtuse.

Antennule a little shorter than the carapace, moderately strong (fig. 5c). First joint consider-
ably longer than the two other joints combined, about three and a half times as long as deep at the
base, with the subdistal part as deep as the middle but a little narrowed between these places; seen
from above it is distinctly thickened on the outer side both at the middle and near both ends. Second
joint short, about half as long again as deep; third joint twice as long as the second, somewhat robust,
with the terminal sete shorter than the joint. — Antennz consist of a minute conical joint termin-
ating in a few sete.

Chelipeds (figs. 5b and 5h) slender. Basal joint somewhat longer than deep, without any
posterior protuberance, but attached to the cephalothorax by an oblique articulation, and the distance
between this articulation and the front lower angle of second thoracic segment is about as long as
the joint. Carpus about twice as long as the basal joint, between three and four times as long as
deep, with the lower margin undulate. Chela about as long as the carpus, three times as long as
broad; movable finger a little longer than the front margin of the hand; fixed finger near the base
considerably broader than the movable, with three low, protruding angles on the distal part of the
incisive margin.

Thoracic segments (fig. 5a) decrease in breadth from second to seventh. Third segment slightly
longer than the second and slightly shorter than the fourth; fifth and sixth segments each somewhat
longer than the others; seventh segment as long as second. Second segment not quite as broad as
the carapace; broadest a little behind the anterior margin, tapering rapidly to the front angles and
considerably to the posterior margin; third segment nearly as the second but its broadest part a little
longer from the front end; fourth segment broadest not much before the middle and tapering to both

CRUSTACEA MALACOSTRACA. II. 6 5

ends; on the three posterior segments their broadest part is behind the middle and in the seventh
somewhat near the posterior margin. The broadest part of each segment has instead of lateral angles
a pair of rounded protuberances on which the legs are inserted. — Thoracic legs moderately long
and very slender. Second (fig. 5i) and third pairs completely similar (fig. 5b); fifth joint of very
moderate length, with a somewhat long seta on the posterior angle; fifth joint very long, much longer
than the fourth and slightly shorter than the sixth, with a very long seta from the anterior distal
angle; seventh joint and claw equal in length and together somewhat shorter than sixth joint. Three
posterior pairs of legs (fig. 5k) with second joint extremely long, about as long as the five following
- joints and the claw combined; sixth joint slightly longer than the fifth, and both these joints. with
some terminal spines, two of which are somewhat long; the claw much longer than seventh joint and
sometimes even about as long as the sixth joint.

Abdomen somewhat shorter than the two posterior thoracic segments combined; the five seg-
ments somewhat narrower than seventh thoracic segment (fig. 5a); the last segment broadly cordiform,
conspicuously broader than the preceding segment and as long as two segments combined. — Pleopods
and uropods mentioned in the description of the genus.

Length of the largest specimen 355".

Subadult Male. The antennule (fig. 5n) are much thicker than in the female; first joint
about three times as long as deep, and nearly as deep at the end as at the base, but narrower at the
middle, as the lower margin of the joint is somewhat concave; second joint considerably deeper than
long; third joint divided by a transverse suture a little before the middle and the proximal part
marked off in this way much thicker than the distal. Antennze consist of a single joint about three
times as long as in the female, about as long as the depth of first antennular joint at its base. —
Abdomen somewhat longer in proportion to the posterior thoracic segments than in the female; the
pleopods have been described in the diagnosis of the genus.

Length of a subadult male 3".

Remarks. As to this extremely interesting species it may be sufficient to refer to the re-
marks on the genus. The animals are completely white.

Occurrence. Taken by the “Ingolf” at three stations in the warm area.

Davis Strait: St. 24: Lat. 63°06' N., Long. 56°00’ W., 1199 fm., temp. 2.4°; I spec.

Denmark Strait: St. 10: Lat. 64° 24’ N., Long. 28° 50’ W., 788 fm., temp. 3.5°; 8 spec. (3 females, 3

males and 2 young spec.).

South of Iceland: St. 4o: Lat. 62°00' N., Long. 21°36’ W., 845 fm., temp. 3.3°; 1 spec.

Leptognathia G. 0. Sars.

This genus comprises 14 species already established in the literature. In the following pages
25 species are described, 19 of which are considered new to science. The genus is thus very large,
comprising 33 species. For reasons mentioned on p. 9, I do not divide it into three or four genera,

though it comprises types not only very different in general aspect but also showing considerable
The Ingolf-Expedition, III. 3. 9

66 CRUSTACEA MALACOSTRACA, IT.

differences in the shape of the molar processes of the mandible, in chelipeds, thoracic legs, pleopods
and uropods. But being unable to say anything about the mandibles in several interesting species, because
my material is too small, and being in doubt whether some of the characters are only of specific value
or ought to be considered of higher importance, I confine myself to dividing the species described or
mentioned in this report into four groups and two of these groups into sub-groups. This arrange-
ment may, I hope, not only facilitate the determination of species but besides afford a general view
of the relationships of the various species. It may be stated that the divisions are founded exclu-
sively on the females, because in several species the pleopods are rudimentary or wanting in this sex

but well developed in the subadult males.

Group a. Uropods long, with both rami two-zointed and the exopod considerably shorter than
the proximal joint of the endopod. Pleopods in the females well developed, biramous, with long sete.
Animals moderately slender or somewhat robust.

The animals of this division, which may be named the Sarsz- or longiremis-group, are some-
what uniform.in general aspect and allied in several features. Sars’ figures of the female of his Z.
longiremts (= L. Sars H. J. H., not L. dongiremis Lilljbg.) convey a fair idea of the aspect of the forms
of this group. The body is moderately slender. The antennz are seven-jointed, as fourth and fifth
joints are separated by a well developed articulation. The basal joint of the chelipeds have the po-
sterior protuberance well developed, with its posterior margin free and rounded. The thoracic legs
are moderately slender, with long or moderately long spines; the three posterior pairs with seventh
joint moderately long, considerably or much longer than the claw and both combined as long as or

longer than the sixth joint. This group may be divided into three subdivisions.

a The movable finger of the chele serrate along the anterior (upper) margin.
Fifth abdominal segment without any hastate process.
Species 41—43.
f&. The movable finger of the chele without serration along the anterior margin.
Fifth abdominal segment without any hastate process.
Species 44—48.
y- The movable finger of the chele without serration along the front margin.
Fifth abdominal segment with the ventral protuberance produced in a long

acute process directed more or less backwards.
Species 49—51.

Group a, subdivision @ (vid. above). -

41. Leptognathia multiserrata n. sp.
(Pl. VI, figs. 6a—6e.)

Female (without marsupium). General aspect as in Z. Sars H.J.H. — Antennule slightly

more than two-thirds as long as the carapace. First joint nearly longer than the three others combined

CRUSTACEA MALACOSTRACA. II. 67

(fig. 6a), not fully three times as long as deep, tapering much from somewhat from the base to the
end; second joint slightly longer than the depth of the first and considerably produced above; upper
margin of third joint only half as long as that of the second; fourth joint scarcely as long as the
upper margin of the second. — Antenne with fifth joint almost half as long again as the fourth,
which is slightly longer than the sixth.

Chelipeds (fig. 6b) extremely robust. Carpus a little more than half as long again as deep,
with the major distal part considerably expanded downwards and the corresponding part of the lower
margin much longer than the proximal portion, considerably convex and with some low, rounded
saw-teeth along its proximal part, viz. that situated beyond the usual seta. Chela as long as the
carpus, less than twice as long as broad; the distal part of the hand somewhat expanded anteriorly
and the corresponding part of thé anterior margin very convex and furnished with about six rounded
saw-teeth, but without any protruding angle above the insertion of the movable finger. Both fingers
thick; the movable finger somewhat shorter than the anterior margin of the hand, with a row of con-
spicuous, rounded saw-teeth along the major part of the proximal half of the anterior margin; the
fixed finger with an oblong, low, subtriangular thickening at the usual sete on the outer side, and
the posterior margin of this thickening has a row of four strong, rounded saw-teeth; the incisive
margin of this finger with three very conspicuous, obtuse, moderately low teeth.

Second and third pairs of thoracic legs (fig. 6c) quite similar, rather slender; posterior distal
spine of fourth joint even longer than fifth joint; sixth joint about one-third as long again as the
fifth and a little longer than seventh with claw. Three posterior pairs of legs (fig. 6d) have the
seventh joint somewhat shorter than the sixth and adorned with a close row of extremely small seti-
form denticles.

The five anterior abdominal segments (fig. 6e) with the median row of ventral protuberances
rounded and somewhat low, seemingly not strongly chitinized. Pleopods with the marginal sete more
than twice as long as the rami. Terminal segment with the sides evenly rounded. — Uropods about
as long as the sixth plus halt of the fifth abdominal segment (fig. 6e); the peduncle more than twice
as long as deep and more than half as long as the first joint of the endopod; first joint of the endopod
slightly longer than the second; exopod half as long as the first joint of the endopod.

Length of the single full-grown or nearly full-grown female without marsupium 3.5™™.

Remarks. This species is easily distinguished by having carpus and chela of the chelipeds
proportionately broader than in any other species of this subdivision and besides by the peculiar shape
of the chela with the rounded teeth at the posterior margin. —- It may be added that the other spec-
imen, which is so young, that seventh pair of thoracic legs are still wanting, has the carpus and the

hand of the chelz less expanded but showing all the characteristic crenulations.

Occurrence. Taken by the “Ingolf’ at a single station.
East of Iceland: St. 4: Lat. 64°07’N., Long. 11°12’ W., 237 fm., temp. 2.5°; 2 spec.

68 CRUSTACEA MALACOSTRACA. II.

42. Leptognathia Sarsii H. J. Hansen.
(Pl. VI, figs. 7a—7 f.)
1909. Leptognathia Sarsit H. J. Hansen, Vidensk. Medd. Naturh. Forening i Kjobenhavn for 1909,
_ P» 229%).
1896. — longiremis G. O. Sars, Account Crust. Norway, Vol. I], p. 27, Pl XII (Not Zanais
longiremis Lilljeborg).

Female. — Antennule nearly three-fourths as long as the carapace. First joint about as long
as the three others combined (fig. 7a), scarcely two and a half times as long as deep, tapering con-
siderably from the base to the end; second joint slightly longer than the depth of the first and some-
what produced above; third joint about half as long as the second; fourth joint distinctly shorter than
the upper margin of the second. — Antenne with fifth joint a little more than half as long again as
the fourth, which is slightly longer than the sixth.

Chelipeds (figs. 7a and 7b) very robust. Carpus only about half as long again as deep, its
distal half somewhat expanded downwards, but the convex lower margin of that part without cren-
ulation. Chela a little longer than the carpus, twice as long as broad, somewhat triangular in outline;
the distal part of the anterior margin slightly convex and furnished with some four to seven sharp
or rounded, small saw-teeth; the terminal corner above the insertion of the movable finger is some-
what protruding, about rectangular. The outer side of the chela has a row of eight or nine pro-
truding teeth situated nearly parallel with and a little removed from the posterior margin, the row
beginning with the strongest tooth somewhat near the distal setee of the posterior margin and going
upwards on the hand where the teeth are gradually smaller and finally disappear. Half or more than
half of the anterior margin of the movable finger is crenulate, with a number of either sharp and
triangular or rounded saw-teeth, the finger itself somewhat shorter than the anterior margin of the
hand. The subdistal part of the incisive margin of the fixed finger with three sharp saw-teeth, the
distal tooth subdivided into two teeth.

The thoracic legs somewhat slender. Second (fig. 7c) and third pairs subequal; posterior ter-
minal spine on fourth joint conspicuously shorter than fifth joint; sixth joint almost or fully half as
long again as the fifth, slightly or distinctly shorter than the seventh with claw. Three ‘posterior
pairs of legs have the seventh joint (fig. 7d) somewhat shorter than the sixth and furnished with an
either distinct or nearly indistinct row of minute, setiform denticles.

Five anterior abdominal segments with the ventral tubercles high and strong (fig. 7e). Pleopods
with the marginal setee between half as long again and twice as long as the rami. Sixth abdominal
segment (figs. 7e and 7f) with the lateral plate on each side produced downwards in a keel which
generally projects in a very conspicuous, obliquely triangular, acute process directed downwards and
backwards, but in some specimens (from four localities in Greenland) these processes are shorter and
obtuse or very short and broadly rounded, but a protrusion is always distinct. — The uropods as long
as the sixth and half of the fifth segment combined; the peduncle a little or somewhat less than

twice as long as deep, but slightly more than half as long as the first joint of the endopod, which is

1) In a foot-note in his Arctic Crustacea I (Bihang Kgl. Sv. Vet. Akad. Handlingar, B. 26, Afd. IV, No 12, 1901)
Ohlin stated that I had proposed the name Z. Sarsdi for this species.

CRUSTACEA MALACOSTRACA. IL. 69

conspicuously longer than the second joint; the exopod more than half as long as the proximal joint
of the endopod.
Length of the largest specimen, a female with marsupium from the Sabine Island, is 5™™ long,

but the majority of the females are only 3.5—4™™.

Subadult Male. Antennule considerably thicker than in the female, five-jointed, the proximal
third of the fourth joint being set off by an articulation and somewhat thickened; first joint somewhat
shorter than the other joints combined, thick to the end; second joint scarcely as thick as the first
and third joint rather thick. Abdomen distinctly a little longer and thicker in proportion to thorax
than in the female. — Length 2.6—2.7™.

Adult Male. Not seen by me, but I suppose that the adult male described and figured by
Sars as belonging to his Z. longiremis is the male of Z..Sarsiz. It has the two proximal joints of the
antennule extremely broad and the chele uncommonly slender, while the thoracic legs have the sixth
joint longer than seventh joint with claw.

Remarks. JL. Sarsi is easily recognized from the other species by the rounded protruding
keel or generally triangular process on the lower lateral surface of last abdominal segment and by the
row of saw-teeth on the outer side of the chela a little from its posterior margin. In the shape of
the hand and the crenulation of the movable finger it agrees with Z. gracilis Kroyer and L. graciloides
Lilljeborg. The form with the obtuse process or rounded lateral keel I name var. odtusata; it is cer-
tainly only a variety, as my material from the Sabine Island contains both specimens with the pro-
cesses obtuse or much reduced. That Z. Sarsi is identical with Z. longiremis G. O. Sars as described
and figured in his standard work is easily seen by the pair of processes on last abdominal segment.
That the real Z. longiremis Lilljeborg is another species is easily decided by two characters found in
Lilljeborg’s diagnosis of the female: “Manus... digito mobili levi” and “Unguis pedum thor. 2:di paris

brevis, et articulo unguifero multo brevior.” This last-named species is described below.

Occurrence. The “Ingolf’ has found this species at three stations.

North of Iceland: St. 128: Lat. 66° 50’ N., Long. 20°02’ W., 194fm., temp. 0.6°; I spec.
MNRAS C52 eee St. 126: Lat. 67°19! N., Long. 15°52’ W., 293 fm., temp. + 0.5°; 7 spec.
_- - -— St. 124: Lat. 67° 4o' N., Long. 15°40’ W., 495 fm., temp. + 0.6°; 4 spec.

Besides Z. Sarsit has been taken by various Zoologists and the II¢ Amdrup-Expedition at a

good number of localities. .

West-Greenland, probably Egedesminde; 1 spec. (var. od¢wsata). Prof. D. Bergendal.

Feeroes: Klaksvig, 1o—15 fm.; about 70 spec. Dr. T. Mortensen.

East Iceland: Breidals Vig, 6 im., mud and black sand; 28 spec. Dr. A.C. Johansen.

— — Seydis Fjord, 6 fm., black sand; 6 spec. Dr. A.C. Johansen.
— — Bakke Fjord, 8—1o fm., black sand; 9 spec. Dr. A. C. Johansen.
East Greenland: Angmagsalik, Lat. 65° 51'N.; 4 spec. (var. ob¢usata). Mag. Kruuse.
_ — Cape Dalton, Lat. 69° 24.6'N., 97—11 fm.; 4 spec. Il¢ Amdrup Exped.
_ _— Turner Sound, Lat. 69° 44’ N., 3 fm.; 1 spec. (var. obtusata). II¢ Amdrup Exped.
— _ North of Stewart Land (about at Lat. 70"/,° N.), 158 fm.; 2 spec. II¢ Amdrup Exped.

70 CRUSTACEA MALACOSTRACA. IL.

East Greenland: Sabine Island, about at Lat. 741/,° N., 3—5 fm.; 15 spec. (the majority belonging
to var. obtusata). 14 Amdrup Exped.

Finally two specimens mentioned by Ohlin (1901) probably belong to this species; they were
taken at the two following localities.

East Greenland: Lat. 74° 35’ N., Long. 18° 23’ W., 18—21 m., sandy mud; 1 spec.

— — Lat. 77° 9'N., Long. 14° 40' E, 9om., soft grey clay; I spec.

Distribution. In the work quoted Sars has stated on his L. lomgiremis: “This species occurs
along the whole Norwegian coast, from Christrianiafjord to Vadso in depths ranging from 30 to 100
fathoms”. Sars has presented the Copenhagen Museum with 25 specimens which must be considered
co-types of his Z. longiremis, but only 13 of these specimens show the characteristic shape of sixth
abdominal segment and belong consequently to Z. Sarsiz H. J. H., while 4 specimens belong to Z. gra-
cilis Kr. as interpreted below and 8 specimens must be referred to the real Z. longiremis Lilljeborg.
The result is that Sars’ utterances on the occurrence of his LZ. /ongiremis along the whole Norwegian
coast are valueless, but it remains certain that Z. Savszz has been taken at Norway, and I suppose only
at the Finmark, because all above-named localities, where this species has been captured by Danish

or Swedish explorers, have an arctic character.

43. Leptognathia gracilis Kroyer.
(Pl. VII, figs. 1a—rd).

1847. Zanais gracilis Kroyer, Naturh. Tidsskr. 2.R. B. I, p. 408.

? — — Kroyer, Voy. en Scand. Crust. Pl. 31, fig. 4,a—i.

1877. — tslandicus G.O.Sars, Arch. for Math. og Naturv. B. II, p. 346.

1885. Lepiognathia longiremis G.O. Sars, Norske Nordhavs-Exped., Crust. I, p. 79, Pl. 7, figs. 17—27.

Female. This species is so closely allied to Z. Sarsi that it may be sufficient to point out
the differences and make mention of some features. — The antennulz (fig. ra) a little more slender
than in Z. Sarsiz; first joint distinctly more than two and a half times as long as deep, somewhat
tapering and as long as the three other joints combined; second joint conspicuously longer than the
depth of the first, somewhat produced above; upper margin of third joint about half as long as that
of the second; fourth joint nearly as long as the second. — Antenne as in ZL. Sarsii.

Chelipeds (figs.1a and rb) scarcely as robust as in Z. SarsiZ; carpus only a little less than
twice as long as deep. Chela slightly longer than carpus, nearly twice as long as broad, somewhat
triangular in aspect; the hand is less or more protruding and angular above the insertion of the moy-
able finger, and the crenulation on the distal part of the anterior margin is distinct or rudimentary;
the outer side of the chela has no row of small tubercles as in Z. Sarszz, while a longer or shorter
part of the front margin of the movable finger is distinctly crenulate.

Second and third pairs of thoracic legs subequal; posterior terminal spine of fourth joint con-
siderably shorter than fifth joint (fig. 1c); sixth joint not quite half as long again as the fifth; seventh
joint with claw a little or conspicuously longer than the sixth joint.

Abdominal segments as in Z. Sarsz excepting that the sixth segment has no trace of any pro-

\

CRUSTACEA MALACOSTRACA. II. 71
truding lateral process or keel. — Uropods (fig. rd) in the main as in Z..Sarsiz; peduncle about twice
as long as deep, a little more than half as long as first joint of the endopod, and this joint is some-
what longer than the second; exopod scarcely more than half as long as the proximal joint of the
endopod.

Length of a female without marsupium from Greenland 3.2™"; an ovigerous female from Nor-
way is 2.2™™ long.

Remarks. This species is, in my opinion, well separated from Z. Sarszz by the absence of a
row of teeth on the outer side of the chela and by having the last abdominal segment simple, without
any acute or rounded lateral process.

In the revised list of the Danish species of most orders of Malacostraca (1909) I referred
L. graciloides V,ilijeborg to LZ. gracilis Kr. Having re-examined the Danish specimens I prefer now to
refer them to Z. graciloides which is re-established as a species closely allied to Z. Sarsiz and L. gra-
cis. L. graciloides agrees with Z. Sarsi in having a row of tubercles on the outer side of the chela,
but the anterior margin of the movable finger has only about five sharp saw-teeth, and the last ab-
dominal segment has, as in Z. gracilis, no trace of a lateral process; it differs from Z. graczlis in pos-
sessing the row of tubercles on the outer side of the chela, and the carpus of the chelipeds has the
distal half more expanded downwards, so that the lower margin of the carpus is at the middle con-
siderably more incised as in Z. gracilis and even more than in the figure of Z. Sars (Pl. VI, fig. 7a);
finally the uropods have the exopod considerably more than half as long as the first joint of the
endopod. Length of the Danish specimens, among which a couple of ovigerous females, 2.2—2.5 ™.

As to Kréyer’s specimen and description I refer to my remarks (p. 23c—31) in the paper on the
Danish fauna; it is clear that my application of the Kréyerian name is not quite certain, but I have
used it, as I did not like to cancel it.

Occurrence. This species has been captured by the “Ingolf” at a single locality.

West-Greenland: Ameragdla (inner end of Ameralik Fjord, near Godthaab), muddy bottom,

II spec. (some of them young).

According to Sars his specimens of Z. zslandicus or (in 1885) LZ. dongiremis, which seem to be-
long to L. gracilis, were taken at Iceland, harbour of Reykjavik.

Distribution. As already mentioned, I found a few specimens of Z. gracilis between co-types
of L. longiremis given by G.O.Sars and taken at Norway. The Copenhagen Museum possesses 3
small specimens from the Kara Sea, 50 fathoms. Kroyer’s specimen was from Spitzbergen. Specimens
taken in the deep water off Aberdeen and in the Moray Firth were determined by Th. Scott as Z. (?)
longiremts Lilljeb., but according to his description and figures the specimens probably belong to Z. gracilis.

Group a, subdivision # (vid. p. 66).
44. Leptognathia Hanseni Vanhdffen
(Pl. VII, figs. 2a—21).
1907. Lepiognathia hanseni Vanh6ffen, Zool. Jahrb., Abth. fiir System. Bd. XXV, p. 513, Taf. 20, Fig. 13—15.

Female. General aspect about as in Z. gracilis. — Antennule (fig. 2a) on the whole a little

72 CRUSTACEA MALACOSTRACA. II.

more robust. First joint a little longer than the three. other joints combined, a little more than two
and a half times as long as deep, moderately tapering; second joint about as long as the depth of
first joint, moderately produced above and somewhat thick; upper margin of third joint half or more
than half as long as the second; fourth joint decidedly shorter than the second, —- Antenne with
fourth joint scarcely half as long again as the fifth, as long as or shorter than the sixth.

Chelipeds (figs. 2a and 2e) somewhat robust; carpus a little or somewhat less than twice as
long as deep, with the distal half distinctly expanded downwards and the corresponding part of the
lower margin moderately convex. Chela slightly or a little longer than the carpus, somewhat more
than twice as long as broad, thus conspicuously less broad than in the three preceding species; the hand
is oblong but not subtriangular, its anterior margin without crenulation and about half as long again
as the movable finger, the distal part above the insertion of the finger flatly rounded or obtuse. The
margin of the movable finger and the outer side of the chela without crenulation. The fixed finger
with three teeth along the distal portion of the incisive margin and the last tooth cleft.

The thoracic legs moderately slender. Second and third pairs subequal (fig. 2b); posterior ter-
minal spine of fourth joint much shorter than fifth joint; sixth joint about half as long again as the
fifth, but a little or very conspicuously shorter than seventh joint with claw. Posterior pairs (fig. 2c)
with the sixth joint about half as long again as the seventh, which has a row of very fine and short,
setiform denticles.

The five anterior abdominal segments (fig. 2d) with the median row of ventral tubercles high
and strong; lateral plates of sixth segment without any expansion or process. The pleopods with the
setee about twice as long as the rami. — Uropods about as long as the two posterior segments com-
bined; the peduncle nearly twice as long as deep, more than half as long as first joint of the endopod;
second joint of the endopod conspicuously or even considerably shorter than the first; exopod a little
more than half as long as the first joint of the endopod.

Length of a large female without marsupium 3.3", of a female with marsupium 2.1™".

Subadalt Male. Antennule much thicker than in the female, five-jointed, the proximal third
of fourth joint being set off by an articulation and somewhat thickened; the first joint is thick to the
end, second almost as thick as the first, and third joint rather thick. Abdomen a little longer and
distinctly thicker than in the female. .

Adult Male (figs.2f—21). This description is based on the single “Ingolf”’ specimen; Van-
h6ffen’s specimen is mentioned in “Remarks”. — Antennile with first and second joints very thick
(fig. 2f); second joint is somewhat more than half as long as the first and slightly longer than the
seventh, which is a little longer than the sixth; bundles of sensory sete originate from the lower
distal end of fourth, fifth and sixth joints.

Chelipeds (figs. 2f—2h) somewhat robust; carpus scarcely half as long again as deep. Chela
not fully half as long again as the carpus, slightly more than twice as long as broad and nearly as
broad as the depth of the carpus; anterior margin of the hand nearly half as long again as the mov-
able finger, which has its incisive margin irregularly serrate from the base to the middle, while the

corresponding margin of the fixed finger is somewhat convex and very finely serrate along nearly

CRUSTACEA MALACOSTRACA. IL. 73

three-fourths of its length; the inner side of the hand (fig. 2h) with a subdistal, transverse row of
peculiar light but broad setze.

Second pair of thoracic legs (fig. 2i) thinner than in the female, with the sixth joint scarcely
half as long again as the fourth and as long as seventh with claw. Three posterior pairs of legs
(fig. 2k) with sixth joint somewhat longer than the fifth and slightly shorter than the seventh, which
is about two and a half times as long as the claw.

Sixth abdominal segment (fig. 21) posteriorly produced into a small, rounded tip. — Endopod
of the uropods somewhat longer than the exopod, two-jointed, with the first joint a little longer and
considerably thicker than the second, before the middle on the upper half of the outer side with some
fine hairs placed in a transverse row.

Length of the specimen 1.3™".

Remarks. JZ, Hanseni is sharply separated from the three preceding species by the more
oblong chele without any serration on the anterior margin of hand or finger; from Z. domgiremis
Lilljeborg and Z. imermis n. sp. it is easily distinguished by the much longer “claw” (seventh joint
plus claw) on second and third pairs of legs. As to the male described, which is easily seen to belong
to Leptognathia, 1 am sure that it belongs to the female, because it has been taken together with a
large number of females and immature males and cannot belong to any other species known from
West Greenland excepting Z. Sarsi and L. gracilis, but no female of any of these species has been
taken at Ameralik, and the male described by Sars as belonging to his Z. /ongiremts probably belongs
to Z. Sarsit and differs widely in some features.

Then the determination of the present species. In the paper on the marine Malacostraca of
West Greenland (1887) I mentioned a specimen which did not agree with Z. dongiremis as interpreted
and figured by Sars in the Norwegian North-Atlantic Expedition, because the chelz had no serration;
I named it “?Lepiognathia longiremis Lilljeborg” and added figures of antenna, chela and uropod.
According to these figures the specimen (which belongs to the Riks Museum in Stockholm) is cer-
tainly identical with the species described here as Z. Hanseni Vanh. Later Vanhéffen captured several
specimens of a species in Karajok Fjord (not very far from Kekertak); he found that his females
agreed with my remarks and figures and finding no positive facts which made it necessary to refer
the form to the real Z. dongiremis Lilljeborg, he named it Z. hansent, described and figured the male
but unfortunately not the more important female. As his male differs from my above-described spec-
imen in a couple of features to be discussed presently, I asked Dr. Vanhéffen to lend me a few spec-
imens; I received the whole material, six females and an adult male, and I beg the Direction of the
Berlin Museum and Dr. Vanhdffen to accept my sincere thanks. The females captured by Dr. Van-
hdffen agree perfectly with my specimens from other localities, but the male must be mentioned
separately. p

Dr. Vanh6ffen’s specimen is 1.5™", thus distinctly a little larger than mine. He figured the
endopod of the uropod as three-jointed, but it is in reality only two-jointed, as no articulation is found
at the base of the transverse row of fine hairs. His figure of the chela does not agree completely
with my specimen, but an examination of his specimen, which has both chele closed and the finer

structure of the incisive margins somewhat indistinct, does not reveal any real difference worth men-

The Ingolf-Expedition. IIT. 3. Io

74 CRUSTACEA MALACOSTRACA. II.

tioning. In his specimen the posterior legs have the seventh joint a little shorter and the claw longer
(viz. half as long as seventh joint) than in my specimen. The only important difference between the
two specimens is that in the antennule the seventh joint is considerably or rather much shorter than the
sixth in Vanh6ffen’s specimen, a little longer than the sixth in my specimen. Btt in spite of this
difference, I think that both males belong to the same species. In males of Leptognathia breviremis
I have observed a conspicuous variation in the length of seventh antennular joint. The female of
L. longiremis is allied to ZL. Hanseni, but the male of Z. longiremis differs strongly from that of Z.
Hansent in the armature of the chelze and the extreme length of seventh joint with claw on the po-
sterior pairs of thoracic legs (vid. Lilljeborg and my figures published in rg10). The male figured by
Sars as belonging to his Z. dongiremts differs also widely from that of Z. Hamsenz. Cousequently I am
induced to think that the specific differences between males of different species of this group @ are
much larger than between Vanhdéffen’s specimen and my own, and that the differences observed be-
tween these two specimens are due only to variation.
Occurrence. Taken by the “Ingolf” at a single locality.
West Greenland: Mouth of Ameralik Fjord, near Godthaab, 5—7o0 fm., shells; more than a
hundred females and immature males, and one adult male.
L. Hanseni has besides been taken at several other places in Greenland by various Zoologists.
West Greenland: Karajok Fjord, ab. Lat. 70°20' N.; several spec. Dr. E. Vanhéffen. :
_ — Kekertak, Lat. 69° 58’ N., 35—40 fm., clay; 1 spec. Nordenskjéld Exped. 1870.
East Greenland: Angmagsalik, ab. Lat. 65'/,°; 2 spec. Mag. Kruuse.
— — — 4—11 fm.; 2 spec. Ryder Exped.
_- -- Tasiusak, Lat. 65°37' N., 20—30 fm., stones with alge; 1 spec. I* Amdrup
’ Expedition.
-- -- Cape Dalton, Lat. 69°24.6' N., 9—11 fm.; 2 spec. II¢ Amdrup Exped.
— — Denmark Island, Lat. 70°27’ N.; 1 spec. Ryder Exped.

The species is hitherto only known from Greenland.

45. Leptognathia longiremis Lilljeborg.
(Pl. VII; figs. 3a—3e.)
1864. Zanazs longiremts Lilljeborg, Bidrag till kannedomen om de inom Sverige och Norrige
forek. Crust. af... Tanaidernas familj, p. 19 (Female and adult male).
1910. Leptognathia longiremis H. J. Hansen, Vidensk. Medd. Naturh. Forening i Kjobenhavn for 1909,
p. 229, Pl. V, figs. 3a—3b.
Female. General aspect as Z. Hanseniz. — Antennule (fig. 3a) moderately strong. First joint
a little longer than the three other joints combined, somewhat less than three times as long as deep,
moderately tapering; second joint slightly longer than the depth of first joint, considerably produced
above and somewhat thick; upper margin of third joint less than half as long as that of the second;
fourth joint a little shorter than the second. — Antenne as in L. Hanseni.
Chelipeds (fig. 3a) nearly as in Z. Hamsent; carpus a little less than twice as long as deep;

CRUSTACEA MALACOSTRACA. IL. 75

the distal half somewhat expanded downwards with its lower margin oblique or distally nearly an-
gular. Chela a little longer than the carpus and somewhat more than twice as long as broad, without
any serration excepting the four teeth on the distal half of the incisive margin of the movable finger;
the anterior margin of the hand considerably longer than the movable finger and its distal part above
the insertion of the finger rounded.

The thoracic legs are rather slender. Second and third pairs similar (fig. 3b); spine on the
posterior angle of fourth joint somewhat shorter than fifth joint, which is at least more than twice as
long as broad; sixth joint nearly half as long again as the fifth and somewhat or considerably longer
than seventh joint with claw. Three posterior pairs with sixth joint as long as or slightly longer
than seventh joint with claw (fig. 3c); the row of minute denticles on seventh joint scarcely distinct.

Five anterior abdominal segments (fig. 3d) with the ventral tubercles high and strong as in
L. Hansent; \ateral plates of sixth segment without any expansion or process. Pleopods with their
setee very long, about three times as long as the rami. — Uropods (figs. 3d and 3e) somewhat shorter
than the two preceding segments combined; peduncle not fully twice as long as deep, conspicuously
more than half as long as the first joint of the endopod; the last-named joint from slightly longer to
a little shorter than the second joint; exopod distinctly more than half as long as first joint of the
endopod.

Length of a fine female without marsupium 2.9™", a female with marsupium is 2.8™". (Females
with marsupium from Norway vary from 2.4™™ to 3.2™" in length.)

Subadult Male. The differences between this animal and the female completely as in
L. Hansent.

Adult Male. This sex has been described by Lilljeborg, and in the above-named paper I
published a couple of analytical figures. I have only seen the single Danish specimen.

Remarks. In the oblong chele without any serration L. longiremis agrees with L. Hansen
and differs sharply from the three other preceding species; by having seventh joint with claw of
second and third pairs of thoracic legs conspicuously shorter than sixth joint it differs from Z. Hansenz,
while it is easily separated from Z. imermis by the ventral row of well developed tubercles on the
five anterior abdominal segments, by much larger difference between the length of the two proximal
antennular joints, ete. That this species is the real Z. dongiremis has been pointed out by me in
1910; especially Lilljeborg’s above-quoted description in his Latin diagnosis of second pair of legs
together with his statement on the chela: “digito mobili levi” proves the correctness of my inter-
pretation.

Occurrence. It has been taken by the “Ingolf” at five stations.

Davis Strait: St. 25: Lat. 63° 30’ N., Long. 54° 25’ W., 582 fm., temp. 3.3°; 17 spet
South-West of Iceland: St. 78: Lat. 60° 37’ N., Long. 27° 52' W., 799 fm., temp. 4.5°; 8 spec.
East of Iceland: St. 4: Lat. 64°07'N., Long. 11° 12' W., 237 fm., temp. 2.5°; 2 spec.

North-East of Iceland: St. 120: Lat. 67° 29' N., Long. 11° 32’ W., 885 fm., temp. + 1.0°; 4 spec.
= - — St. 119: Lat. 67° 53’ N., Long. 10° 19’ W., toro fm., temp. + 1,0°; 6 spec.

Furthermore it rere been taken by the II‘ Amdrup Expedition at a single locality.

Jan Mayen, 55 fm.; 2 spec.

10*

76 CRUSTACEA MALACOSTRACA IL.

Distribution. Lilljeborg examined specimens taken off Bohuslan and at Molde (west coast
of Norway at Lat. 62°42’ N.). Material from Norway determined by Sars contained, as already stated,
several specimens of this species together with two other species. In 1910 I enumerated two localities
in Skager Rak, 110 and 125 fm, and one locality in Kattegat, 20 fm. — All other localities for Z.
longiremis mentioned in the literature ought to be discarded as doubtful or erroneous, and the material

in question re-examined by the aid of the present paper.

46. Leptognathia inermis n. sp.
(Pl. VII, figs. 4a—4¢.)

Female. The antennule (fig. 4a) differ conspicuously from those in the preceding forms.
First joint is robust, considerably shorter than the three other joints combined, only twice as long as
deep and somewhat tapering; second joint is thick and long, with its upper margin somewhat longer
than the depth of the first joint and it is somewhat produced above; third joint with its upper margin
not fully half as long as the second; fourth joint somewhat shorter than the second. — Antenne with
fifth joint more than half as long again as the fourth, which is distinctly shorter than the sixth.

Chelipeds (figs. 4a and 4b) robust. Carpus extremely deep, only about half as long again as
deep, with the distal half conspicuously or, generally, strongly expanded downwards and the corre-
sponding part of the lower margin very convex, nearly semicircular. Chela as long as or a little
longer than the carpus, from slightly more to distinctly less than twice as long as broad, thus rather
broad, with the distal anterior corner of the hand at the insertion of the movable finger angular and
frequently protruding, subrectangular or even with a subacute angle; movable finger uncommonly
broad towards the base; with the anterior margin glabrous excepting in a single immature specimen
(from East Greenland) which has nearly half of this margin sinuate, with three impressions (fig. 4g);
fixed finger with three teeth on the distal part of the incisive margin, but these teeth are frequently
obtuse and one or two among them poorly developed.

The thoracic legs are somewhat shorter and thicker than in the five preceding species. Second
and third pairs subsimilar (figs. 4c and 4d); the spine from the distal posterior angle of fourth joint
very long, from a little longer to somewhat shorter than fifth joint; the last-named joint varies con-
siderably in breadth, being sometimes twice as long as broad, but most frequently broader, even only
somewhat longer than broad, with the posterior margin straight or with a couple of low serrations;
(perhaps the extreme breadth is due to compression originating from the influence of alcohol); sixth
joint considerably longer than, sometimes even half or slightly more than half as long again as, the
fifth and always considerably longer than seventh joint with claw. Posterior pairs of legs (fig. 4e)
with sixth joint about as long as seventh plus the short claw; seventh joint with the row of minute
setiform denticles more or less distinct. an

Five anterior abdominal segments (fig. 4f) without any ventral median row of real tubercles,
as the lower median margin of each segment is, seen from the side, rather flatly convex. Pleopods
as in L. longiremis. Sixth abdominal segment, seen from the side (fig. 4f), generally, and in full-grown

specimens probably always, more flatly convex than in all preceding species. — Uropods longer than

CRUSTACEA MALACOSTRACA. II. 77

the two posterior abdominal segments combined; peduncle somewhat or considerably less than twice
as long as deep, about half as long as the first joint of the endopod; second joint of the endopod
slightly or a little shorter than the first; exopod distinctly more than half as long as first joint of the
endopod.

Length of a large female without marsupium 2.8™", of a female with marsupium 2.15™".

Subadult Male. Antennule only four-jointed, but the two proximal joints are considerably,
the third joint somewhat, thicker than in the female. The abdomen proportionately somewhat longer
and thicker than in the female. — Length 2.1—2.3™.

Remarks. JZ. imermis differs from all preceding species of this genus by having the first an-
tennular joint shorter in proportion to its depth and to the length of second joint; in this respect it
agrees with some of the following species. From Z. longiremis, with which it agrees in having seventh
joint with claw of second and third pairs of legs conspicuously shorter than sixth joint, it differs in
the antennule, in having no ventral abdominal tubercles, shorter and stouter legs, the chela
broader, etc.

Occurrence. It has been taken by the “Ingolf” at five stations.

East of Iceland: St.58: Lat. 64°25'N., Long. 12°09! W., 211 fm., temp. 0.8°; 1 spec.

— - _ St. ror: Lat. 66°23’ N., Long. 12°05) W., 537 fm., temp. + 0.7°; 7 spec.

North of Iceland: St. 126: Lat: 67°19' N., Long. 15°52’ W., 293 fm., temp. + 05°; I spec.

—- so St. 124: Lat. 67°40’ N., Long. 15°40’ W., 495 fm., temp. + 0.6°; 1 spec.

Jan Mayen: St. 115: Lat. 70°50’ N., Long. 8°29’ W., 86 fm., temp. 0.1; ab. 75 spec.

Besides it has been secured by the IJ¢ Amdrup Exped. at a single locality.

East Greenland: Cape Dalton, Lat. 69°24.6’N., 9—11 fm.; 1 spec. (The chelze of this specimen

has the anterior margin of the movable finger sinuate (fig. 4¢)).

47. Leptognathia brachiata un. sp.
(Pl. VI, figs. 5a—5h.)

Female. Antennule two-thirds as long as the carapace (figs. 5a—5b). First joint (fig. 5c)
robust, somewhat longer than the three other joints combined, a little more than twice as long as
thick, moderately tapering; second joint stout, a little produced above, with the upper margin some-
what longer than the depth of first joint and a little more than half as long as that joint; third joint
with the upper margin a little less than half as long as that of the second; fourth joint proportion-
ately short, considerably shorter than the second. — Antenne with fifth joint about half as long again
as the fourth, which is a little shorter than the sixth.

Chelipeds (fig. 5d) moderately robust. Carpus somewhat less than twice as long as deep, with
less than the distal half much expanded downwards, the corresponding lower margin being strongly
convex and almost subangular. Chela a little shorter than the carpus, a little more than twice as
long as broad, without any serration; anterior margin of the hand a little longer than the movable
finger, with the lower angle above the insertion of the finger scarcely rounded; movable finger of

moderate breadth; fixed finger with three acute saw-teeth on the distal part of the incisive margin.

78 CRUSTACEA MALACOSTRACA. TI.

Thoracic legs rather slender. Second and third pairs subsimilar (fig. 5e); posterior spine on
fourth joint as long as fifth joint, which has two long distal spines; sixth joint about half as long
again as the fifth and somewhat longer than seventh with claw. Three posterior pairs (fig. 5f) with
seventh joint only a little shorter than the sixth and its row of minute setiform denticles rather di-
stinct; claw somewhat long, longer than in the preceding forms.

Five anterior abdominal segments feebly developed or scarcely distinct, the lower margin of
the segments being somewhat flatly convex (fig.5h). Pleopods with long sete. — Uropods distinctly
longer than the two posterior segments combined and longer than in any other species of this genus
(figs. 5g and 5h), as the peduncle is very long, almost four times as long as deep and about as long
as the first joint of the endopod; second joint of the endopod slightly longer than the first joint;
exopod from slightly less to slightly more than half as long as first joint of the endopod.

Length of a female with marsupium 3.3™".

Remarks. This fine species is easily distinguished from all other forms of the genus known
to me by the very long peduncles of the uropods.

Occurrence. This species has been taken by the “Ingolf” at two stations.

Davis Strait: St.25: Lat. 63°30'N., Long. 54°25’ W., 582 fm., temp. 3.3°; 11 spec.

- -- St. 24: Lat. 63°06’ N., Long. 56°00' W., 1199 fm., temp. 2.4°; 6 spec.

The marsupium of one of the females from Stat. 25 contains two ovisacs of an unknown species

of the family Choniostomatide. It is, I believe, the first time that the existence of a species of this

family of parasitic Copepods has been observed in any form of the order Tanaidacea.

48. Leptognathia alba nu. sp.
(Pl. VI, figs. 6a—6e.)

Specimen without marsupium. The single specimen is either a female without mar-
supium or, judging from the thick antennulz, more probably a male so far from maturity, that the
fourth antennular joint has not been divided into two joints. The body is conspicuously more robust
than in the preceding forms.

Antennulz (fig. 6a) slightly more than two-thirds as long as the carapace, very robust. First
joint slightly longer than the three other joints combined, not fully two and a half times as long as
deep and tapering feebly; second joint thick, as long as the depth of the first and somewhat produced
above; upper margin of third joint only about one-third as long as that of the second; fourth joint
somewhat shorter than the second. — Antenne with fifth joint scarcely half as long again as the
fourth, which is as long as the sixth.

Chelipeds (fig. 6b) moderately robust. Carpus somewhat more than twice as long as deep,
with the proximal half of the upper margin somewhat concave; the distal half is feebly expanded
downwards. Chela somewhat shorter than the carpus, somewhat more than twice as long as broad,
oblong-triangular in aspect, without serrration; the anterior distal corner of the hand not rounded;
the movable finger somewhat broad and somewhat shorter than the anterior margin of the hand.

Thoracic legs somewhat slender. Second and third pairs subequal (fig. 6c); posterior spine on

CRUSTACEA MALACOSTRACA. IT. 79

fourth joint distinctly longer than fifth joint; distal spines on fifth joint uncommonly long; sixth joint
not fully half as long again as the fifth; seventh joint with claw scarcely longer than fifth joint.
Three posterior pairs (fig. d) with sixth joint almost as long as seventh with claw; setiform denticles
on seventh joint nearly inconspicuous; claw proportionately long.

Five anterior abdominal segments with the median ventral tubercles peculiarly shaped (fig. 6 e),
as each tubercle, seen from the side, is somewhat low, because its lower margin is concave instead of
convex. Pleopods with their marginal setee about three times as long as the rami. — Uropods a
little longer than the two posterior segments combined; peduncle about half as long again as deep,
only half as long as the first joint of the endopod; second joint of the endopod slightly longer than
the first; exopod about half as long as the proximal joint of the endopod.

The specimen is 3.7" long; it is quite white.

Remarks. L. alba is easily distinguished from all above-described species by the shape of

the ventral abdominal tubercles; the shape of the joints of the chelipeds also affords good characters.

The species is uncommonly robust.

Occurrence. Taken by the “Ingolf” at a single station.
South-West of Cape Farewell: St. 22: Lat. 58°10’ N., Long. 48°25’ W., 1845 fm., temp. 1.4°; I spec.

Group a, subdivision ; (vid. p. 66).

49. Leptognathia hastata n. sp.
(Pl. VII, figs. 7a—7 g.)

Female (without marsupium). Antennule somewhat or a little shorter than the carapace.
First joint (fig. 7a) a little shorter than the three other joints combined, somewhat more than twice
as long as deep and considerably tapering; second joint thick and long, a little more than half as
long as the first and somewhat produced above; upper margin of third joint a little less than half as
long as that of the second; fourth joint somewhat shorter than the second. — Antenne with fifth
joint slightly more than half as long again as the fourth, which is as long as the sixth.

Chelipeds (fig. 7b) rather robust. Carpus only about, or even less than, half as long again as
deep, with the distal part strongly expanded downwards and the corresponding lower margin very
convex. Chela a little longer than the carpus, about twice as long as broad, without serration; hand
with the distal anterior corner subrectangular and protruding; movable finger somewhat broad, a
little shorter than the anterior margin of the hand; fixed finger with the usual teeth on the inci-
sive margin.

Thoracic legs moderately strong. Second and third pairs subequal (fig. 7¢); posterior distal
spine on fourth joint a little longer than the fifth joint; sixth joint about half as long again as the
fifth and its lower margin with a more or less distinct row of small denticles; seventh joint with claw
slightly longer than fifth joint. Three posterior pairs (fig. 7d) have seventh joint considerably shorter
than the sixth and the row of setiform denticles is very conspicuous (fig. 7), the denticles being con-

spicuously longer than in the preceding forms; claw somewhat more than half as long as seventh joint.

80 CRUSTACEA MALACOSTRACA. II.

The two anterior abdominal segments with the ventral tubercles wanting or rudimentary;
third and fourth segments with the tubercles either rudimentary or rather low and triangular; fifth
segment (fig. 7h) with the tubercle high and posteriorly produced into a very long, acute process pro-
jecting horizontally backwards and reaching the middle of sixth segment; in a single specimen (from
Stat. 102) the tubercle of fifth segment is rudimentary with the process very short, being undeveloped
from one reason or another. Pleopods with the sete almost twice as long as the rami. — Uropods
as in the majority of the preceding species, not fully as long as the two posterior segments combined;
peduncle somewhat less than twice as long as deep; proximal joint of the endopod not quite as long
as the peduncle and about as long as or a little longer than the distal joint (fig. 7g); exopod scarcely
half as long as first joint of the endopod.

Length of the females without marsupium 2.5—2.8™",

Remarks. The differences between Z. astata and the two following species are pointed out
in the “Remarks” on these species.

Occurrence. ZL. hastata has been taken by the “Ingolf” at two deep-sea stations in the
cold area.

East of Iceland: St. 102: Lat. 66°23’ N., Long. 10° 26’ W., 750 fm., temp. + 0.9°; 2 spec.

North of Iceland: St.125: Lat. 68°08’ N., Long. 16°02’ W., 729 fm., temp. + 0.8°; I spec.

so. Leptognathia armata n. sp.
(Pl. VIII, figs. ra—rf)

Female (without marsupium) and subadult Male. This species is so closely allied to Z,
hastata that it is nearly sufficient to point out the differences. — The antennule of the female almost
as in L. hastata. The antennule of the subadult male (fig. 1a) five-jointed, very thick; first joint a
little shorter than the other joints combined, a little more than twice as long as deep, at the end
somewhat less deep than somewhat beyond the base; second joint a little more than half as long as
the first, somewhat more than half as long again as deep and considerably produced above; third joint
short and thick; fourth and fifth joints combined somewhat shorter than the upper margin of the
second, and fourth joint considerably deeper than long.

The chelipeds have the carpus two-thirds as long again as deep and its distal part is very
moderately expanded downwards with the corresponding lower margin somewhat convex (fig. rb) —
thus the carpus is conspicuously longer in proportion to depth and less expanded downwards than in
L. hastata. The chela is slightly shorter than the carpus and a little more than twice as long as
broad, otherwise as in Z. hastata.

Second and third pairs of legs (figs. tc and 1d) nearly as in Z. hastata, but the denticles on
the posterior margin of sixth joint are very distinct, in the female specimen (fig. rd) besides developed
on fifth joint. Three posterior pairs (fig. 1c) with the setiform denticles on seventh joint scarcely as
long as in L. hastata.

Four anterior abdominal segments (fig. rf) with the ventral tubercles strongly chitinized, rather

large and varying in shape, either subconical or a little obliquely and somewhat broadly truncate.

CRUSTACEA MALACOSTRACA. II. 81

The process from fifth ventral tubercle is still broader at the base and longer than in Z. hastata and
besides not horizontal but directed backwards and somewhat downwards. Pleopods and uropods about
as in L. hastata.

Length of the female without marsupium 3.8™", of the subadult male 3.3™.

Remarks. JZ. armata is so closely allied to LZ. hastata that I hesitated before establishing it
as a separate species. But it seems to be a good deal larger than Z. Aastata and differs by having
the carpus of the chelipeds less robust and conspicuously less expanded downwards, furthermore by
the much more developed ventral abdominal tubercles and a different direction of the process from
. fifth segment. And judging from the species belonging to the subdivions a and f of the same group
a the shape of the carpus and the development of abdominal tubercles afford valuable specific cha-
racters. Finally Z. avmata was taken in very deep water with the temperatures above zero, while Z.
hastata was captured in considerable depths in the cold area. — The differences between both species
and the next form, Z. Amdrufit, are pointed out below.

Occurrence.. LZ. hastata has been taken by the “Ingolf’ at two stations.

Davis Strait: St. 36: Lat. 61°50’ N., Long. 56°21' W., 1435 fm., temp. 1.5°; 1 spec. (9).

South-West of Cape Farewell: St. 22: Lat. 58°10’ N., Long. 48°25’ W., 1845 fm., temp. 1.4°; I spec.

(subad. male).

51. Leptognathia Amdrupii n. sp.
(Pl. VIII, figs. 2a—ac.)

Female. So closely allied to Z. hastata and L. armata that it may be sufficient to mention
some features. — The antennule (fig. 2a) are distinctly more slender than in those species, and the
first joint is slightly more than two and a half times as long as deep, but the relative length of their
joints shows no essential difference. — The chelipeds (fig. 2b) are a little less robust; the carpus is
about twice as long as the depth of its distal half which, in strong contradistinction to the other
species, is distinctly less deep than the proximal half and with the lower margin nearly straight;
chela a little longer than the carpus and more slender than in the two species mentioned, being consider-
ably more than twice as long as broad; the movable finger almost longer than the front margin of
the hand and as broad as the fixed finger. — Second pair of legs (fig. 2c) without spinules on the
posterior margin of sixth joint.

Four anterior abdominal segments with the ventral tubercles rather low; the process from
fifth segment about as long as in Z. hastata but less horizontal, though scarcely directed as much
downwards as in Z. armata. Pleopods and uropods in the main as in Z. hastata; exopod of right
uropod two-jointed and distinctly more than half as long as first joint of the endopod, while the
exopod of left uropod is much shorter and one-jointed, as second joint has not been developed.

Length of the female with marsupium 2.7™".

Remarks. By the shape of the carpus of the chelipeds Z. Amdrupii is easily distinguished
from the two preceding species. It differs’ on the whole a little more from Z. /as‘afa than from Z.

armata, but while the last-named species is only known from stations with positive temperatures at

The Ingolf-Expedition, III. 3. II

82 CRUSTACEA MALACOSTRACA. IT,

the bottom aud depths exceeding 1400 fathoms, Z. Amdrupit was found in comparatively low water
at the cold East Greenland.
_ The name is given in honour of G. C. Amdrup, Captain in the Danish Navy and the able
leader of two Danish exploring expeditions to East Greenland.
Occurrence. Taken by the II¢ Amdrup Expedition at a single locality.
East Greenland: Forsblad Fjord, Lat. 72° 27' N., go—4o fm., 1 spec. (female with marsupium).

Group b. Uvropods long, with both rami two-zointed and the exopod conspicuously shorter than
the first joint of the endopod. Pleopods in the female somewhat small with the marginal sete at most
as long as the rami or almost rudimentary. Animals slender or very slender.

Species 52—53.

The animals of this group are on the whole allied to those of group a, but they are more

slender with the pleopods considerably or much reduced and the articulation between fourth and fifth

joint of the antennze feebly developed.

52. Leptognathia tuberculata n. sp.
(Pl. VIII, figs. 3a—3f)

Female. Body much more slender than in any of the preceding species, but the animal in
other respects rather similar in general aspect. — Antennule (fig. 3a) slightly more than two-thirds
as long as the carapace. First joint a little shorter than the three other joints combined, somewhat
more than twice as long as deep, considerably tapering; second joint considerably produced above,
distinctly more than twice as long as deep and with the upper margin conspicuously more than half
as long as first joint; third joint short, fourth joint much shorter than the upper margin of the second.
— Antennee with the articulation between fourth and fifth joint feebly developed, less or more indi-
stinct, and fifth joint about twice as long as the fourth, which is a little shorter than the sixth.

Chelipeds somewhat robust (fig. 3a). Carpus only half as long again as deep, with the distal
half strongly expanded downwards and the corresponding part of the lower margin much curved and
even subangular. Chela somewhat longer than the carpus and twice as long as broad, with the an-
terior lower corner of the hand angular; movable finger a little shorter than the anterior margin of
the hand and with the subbasal part slightly narrower than the fixed finger, which has four teeth on
the incisive margin.

Thoracic legs somewhat short (fig. 3a) and moderately slender. Second (fig. 3b) and third
pairs with the spines on fourth and fifth joint very long; sixth joint nearly half as long again as the
fifth, which is a little shorter than seventh with claw. Three posterior pairs (fig. 3c) with sixth joint
as long as seventh with claw; seventh joint without any distinct row of minute sete.

Four anterior abdominal segments (fig. 3d) with the median row of ventral tubercles low, while
the tubercle on the fifth segment is more than twice as high, broadly conical, acute and even a little
acuminate. Pleopods almost rudimentary, biramous, but the rami are shorter and much narrower than

the small peduncle (fig. 3e), with a small terminal seta and a few minute marginal sete. — Uropods

CRUSTACEA MALACOSTRACA. IL. 83

as in the species of group a, scarcely as long as the two posterior segments combined; peduncle twice
as long as deep, distinctly more than half as long as the first joint of the endopod; the joints of the
endoped subequal in length and the first joint conspicuously less than twice as long as the two-
jointed exopod.

Length of a female with marsupium 3.3™", of a female without marsupium 3.1™".

Subadult Male. — The antennule five-jointed and as usually much thicker than in the
female. In my single specimen the ventral tubercles on the four anterior abdominal segments are
somewhat higher than in the females, while the tubercle of the fifth segment is obtuse, but probably
- damaged or misshaped. The pleopods are well developed (fig. 3f); as fig.e, representing a pleopod of
the female, and fig. 3f, representing that of the male, were drawn with the same degree of enlargement,
the comparison between these two figures will convey an idea of the enormous difference in size and
development, and it may be added that the female is considerably larger than the subadult male in
question. The endopod is nearly twice as long as the peduncle and has its distal rounded margin
furnished with setee as long as the ramus; the exopod is somewhat longer than the endopod, but the
setee along the terminal margin are only as long as those of the endopod. — Length of the spec-
imen 2.4™™,

Remarks. JZ. /uberculata is more slender than any among the above-described species; the
female is easily recognized by the nearly rudimentary pleopods and the development of the ventral
abdominal tubercles. The shape of the chelipeds and the relative length of the joints of the anten-
nule afford additional characters.

Occurrence. The species has been taken by the “Ingolf’ at two deep-sea stations in the
warm area.

Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 4 spec.

= — St. 36: Lat. 61°50’ N., Long. 56°21’ W., 1435 fm., temp. 1.5°; I spec.

53. Leptognathia uncinata n. sp.
(Pl. VIII, figs. 4a—4i.)

Female (without marsupium). This species is closely allied to Z. dentifera G. O. Sars, of
which a co-type presented by Sars himself has been examined. The two species agree with one an-
other in the following more important particulars. The antennule are characteristic (fig. 4a); first
joint is considerably shorter than the three others combined, very thick, conspicuously less than twice
as long as deep; second joint is uncommonly long and thick, about two-thirds as long as the first,
somewhat produced above, and its upper margin a little longer than the two distal joints combined
and a little more than twice as long as the depth of the joint. — Antenne with fourth joint about
half as long as the fifth, and the articulation between them feebly developed. Chela (fig. 4b) as long
as the carpus, twice as long as broad, with the two sete on the posterior margin extremely thick;
the anterior distal angle above the insertion of the movable finger is protruding and even produced
as a short, obtuse process. -- Second pair of legs (fig. 4c) with fifth joint a little shorter than the

fourth and only half as long as the sixth, which is considerably longer than seventh joint with claw
nih

84 CRUSTACEA MALACOSTRACA. II.

and furnished with minute denticles along the lower margin; seventh joint strongly marked off from
the claw, with a distinct spinule at the end. — Ventral tubercles on the five abdominal segments
very low (fig. 4d). — Uropods as long as in the Sarsd-group; the peduncle (fig. 4e), measured to the
insertion of the rami, slightly longer than the first joint of the endopod, thick and distally above pro-
duced in a large, oblong, subacute or acute process directed somewhat backwards and gradually curved
much upwards; endopod with its two joints subequal in length; the two-jointed exopod somewhat (in
L. dentifera) or considerably (in Z. wncinata) shorter than first joint of the endopod.

But the two species are separated by two features. In ZL. dentifera G. O.S. the carpus of the
cheliped is a little less than twice as long as deep, while in Z. wucinata it is conspicuously deeper,
being only half as long again as deep (fig. 4b), the distal third being considerably expanded down-
wards. In ZL. dentifera the pleopods are very small, slightly longer than in Z. twberculata (comp. fig. 34),
in my specimen from Norway even less developed than according to Sars’ fig. 2 A/p, and each ramus
has a single seta less than half as long as the ramus and some tiny hairs; in ZL. wucinata the pleopods
(fig. 4d), though reduced in size, are much larger than in ZL. dentifera with a number of very conspi-
cuous sete and some among them as long as the rami.

Length of the specimen 2.1™™.

Adult Male. Antennule seven-jointed (fig. 4f); the two proximal joints robust, together
considerably longer than the other joints combined, and second joint about two-thirds as long as the
first; seventh joint half as long again as the sixth; fourth, fifth and sixth joints each with a bundle
of sensory filaments from the lower end. — Antenne with the articulation between fourth and fifth
joint very distinct; fifth joint scarcely twice as long as the fourth, but only a little longer than
the sixth.

Chelipeds somewhat robust (fig. 4f). Carpus about half as long again as deep, with the distal
third distinctly expanded downwards. Chela considerably longer than the carpus, twice as long as
broad, nearly triangular in aspect; distal anterior angle of the hand above the insertion of the finger
protruding but a little rounded; movable finger a little shorter than the anterior margin of the hand,
somewhat narrow, being scarcely half as broad as the fixed finger at the base, and its incisive margin
without serration; fixed finger with half of its incisive margin finely serrate.

Second (fig. 4g) and third pairs of legs with the sixth joint only a little longer than the fifth
and about as long as seventh joint with claw. Posterior pairs (fig. 4h) with seventh joint elongate,
slightly longer than the sixth and about half as long again as the claw.

Sixth abdominal segment (fig. 4i) posteriorly rounded. — Uropods with the peduncle as long
as second joint of the endopod, which is slightly shorter but much thinner than its first joint; the
two-jointed endopod somewhat more than half as long as first joint of the endopod.

Length 1.5™™,

Remarks. It was after considerable hesitation that I established Z. wxcinata as a new species,
but the two differences -pointed out between the females of Z. wxcinata and L. dentifera seem to be
so important, that the deep-sea form ought to be established as a separate species.

I think that the reference of the adult male to this species is quite certain. This male is so

small that it cannot belong to Z. armata or L. tuberculata. taken at the same station. Furthermore

CRUSTACEA MALACOSTRACA. II. 85

the chelipeds of the male agree so well with those of the female in several particulars: length in
proportion to depth or breadth of carpus and chela, protruding anterior angle of the hand, rather
narrow movable finger and general shape of the fixed finger, and this agreement is larger than other-
wise generally found in the chelipeds of the two sexes. The thickness and relative length of the
two proximal joints of the antennule is also nearly the same in the two sexes, and perhaps the most
important character is the long peduncle of the uropods in both sexes, as this joint in the male is
nearly as long as, in the female slightly longer than, the first joint of the endopod, while in the
females of all preceding species of the genus excepting the large Z. drachiata the peduncle is much
shorter than the first joint of the endopod.

Occurrence. Taken by the “Ingolf at the following station.

Davis Strait: St. 36: Lat. 61°50’ N., Long. 56°21' W., 1435 fm., temp. 1.5°; 2 spec. (? and <j).

It may be mentioned that the “Ingolf” at Stat. 103: Lat. 66° 23' N., Long. 8°52’ W., 579 fm., temp.
+ 0.6°, captured a considerably smaller, juvenile specimen, which is at least allied to Z. wncifera and
L. dentata, but the process from the peduncle of the uropods is very small and subhorizontal, prob-

ably not yet developed.

Group c. Uvropods with the endopod twozointed, the exopod well marked off, one-zotnted.
These characters pointed out are very practical. But the group comprises in reality rather
heterogenous elements, and its nine species mentioned on the following pages may be referred to three
natural subdivions.
a. Pleopods wanting or extremely rudimentary in the females. The basal joint
of the chelipeds normal, possessing a posterior process with the hind margin

free and rounded. Slender species. Species 54—58.

f. Pleopods very distinct with well developed sete in the females. The basal

joint of the chelipeds normal, as in subdivision « Very stout species.
Species 59—60.

y- Pleopods very distinct with well developed sete in the females. The basal
joint of the chelipeds aberrant, in a lateral view the long major part of its
posterior margin is vertical and attached to the cephalothorax at or even
before its middle, while the posterior process is short and situated more on

the lower than on the lateral side of the cephalothorax. Species 61—62.

Group c, subdivision a (vid. above).

54. Leptognathia manca G. O. Sars.
(Pl. VIII, figs. 5a—5d.)
1881. Leptognathia (?) manca G. O. Sars, Arch. for Math. og Naturv., B. 7, p. 44.
1806. —- - _ Account Crust. Norway, Vol. II, p. 30, Pl. XIV, fig. 2.
Though Sars’ description and figures are sufficient for the recognition of this species, I think

it useful for comparison with the following forms of this subdivision to give a new description and a

86 CRUSTACEA MALACOSTRACA. II.

couple of analytical figures of the female, together with corresponding figures of the hitherto unknown
subadult male.

Female. The shape of the body from above is shown well by Sars’ fig. 3; third to sixth
thoracic segments have their lateral margins far from. parallel, but conspicuously though not strongly
angular, and the body tapers in breadth from the third segment.

Antennule (fig. 5a) considerably shorter than the carapace. First joint a good deal shorter than
the other joints combined, about twice as long as deep, considerably tapering; second joint slightly
more than half as long as the first and much produced above; upper margin of third joint distinctly
less than half as long as that of the second; fourth joint about as long as the second and a little
shorter than its terminal sete. — Antenne with fourth and fifth joint completely fused, without any
vestige of an articulation between them.

Chelipeds (fig. 5a) somewhat slender. Basal joint not much longer than the distance between
the rounded hind margin of its well developed posterior process and the front margin of second seg-
ment. Carpus almost twice as long as deep, with the lower margin feebly convex. Chela a little
longer than the carpus, two and a half times, or even more, as long as broad; hand without any pro-
truding anterior angle at the insertion of the finger, and this finger is about as long as the front
margin of the hand; fixed finger slightly broader than the movable, with the teeth on the incisive
margin distinct. ;

Second and third pairs of legs (fig. 5a) moderately strong or moderately slender; the spine on
the posterior angle of fourth joint about as long as the fifth joint, which is somewhat shorter than
the sixth joint, while the spines on its distal angles are long, though shorter than the joint; seventh
joint with claw about as long as the sixth joint. — Three posterior pairs of legs essentially as in the
Sarsi-group.

Abdomen (fig. 5b) with the lower margin of the five anterior segments conspicuously convex,
but not shaped as tubercles. — Uropods moderately long, conspicuously longer than the sixth seg-
ment; peduncle a little longer than deep, conspicuously shorter than the first joint of the endopod,
which is slightly shorter than second joint; the one-jointed exopod nearly as long as, or slightly
longer than, the first joint of the endopod.

Length of a female with marsupium 2'™", of a female without marsupium 2.2™",

Subadult Male. In the main as the female, but it differs by much thicker antennule and
in the abdomen. The antennule (fig. 5c) are conspicuously longer as compared with the carapace
than in the female, only four-jointed, and their three proximal joints together with the proximal part
of fourth joint are much thicker than in the other sex. — The five anterior abdominal segments
(fig. 5d) are longer than in the female, and the median ventral margin of each segment is shaped as
a moderately high, subtriangular tubercle with the end rounded. The pleopods are somewhat long
with the outer ramus much longer than the peduncle and longer than the inner ramus; the terminal
setee about as long as the rami. — Length 1.8™",

Remarks. ZL. manca differs from ZL. ventralis n. sp. by a different shape of second and third
antennular joints, by having no ventral process on the second thoracic segments and by the posterior

margin of the basal joint of the chelipeds being rather remote from the front end of the second

CRUSTACEA MALACOSTRACA. II. 87

thoracic segment. From Z. subegualis it differs in the shape of the body, which in the latter species
is extremely slender with the lateral margins nearly parallel; furthermore the exopod of the uropods
is proportionately conspicuously longer in Z. swbegualis than in L.manca. L.manca is rather remote
from the other forms of group c.

Occurrence. The “Ingolf’ has taken this species at two localities.

Davis Strait: St. 25: Lat. 63°30’ N., Long. 54°25’ W., 582 fm., temp. 3.3°; 23 spec.

South of East-Iceland: St. 90: Lat. 63°43’ N., Long. 14°34’ W., 90 fm., temp. 7.0°; 1 spec.

Distribution. Sars had this species from two widely separated places on the Norwegian

coast, at depths of roo—150 fathoms. It has scarcely been mentioned by any other author.

55. Leptognathia subzqualis n. sp.
_ (Pl. VI, figs. 6a—6f,)

Female. Body extremely slender (fig.6a), nine or ten times as long as broad, seen from above
nearly cylindrical, with fourth and fifth thoracic segments slightly broader than the carapace or the
abdomen; the lateral margins of each thoracic segment nearly parallel, not angular but a little or con-
spicuously rounded at both ends of each segment. — Carapace, seen from above, about half as long
again as broad, twice or more than twice as long as second thoracic segment but somewhat shorter
than the two anterior segments combined; the front end of the carapace conspicuously more than half
as broad as the carapace somewhat behind the middle; rostral process somewhat narrow.

Antennule almost as long as the carapace (fig. 6b), somewhat robust. First joint nearly as
long as the three other joints combined, a little or somewhat more than twice as long as deep and
with the proximal third considerably thickened downwards; second joint much produced above, with
the upper margin distinctly more than half as long as first joint and twice as long as the depth of
the joint itself; third joint with the upper margin very short; fourth joint conspicuously shorter than
the second, much shorter than some of the terminal sete. — Antenne with fourth and fifth joints
completely fused, without any vestige of an articulation.

Chelipeds (fig. 6b and 6c) moderately strong. Basal joint long, nearly as long as the carpus,
with the rounded posterior process reaching near to the front lower angle of second thoracic segment.
Carpus distinctly less than twice as long as deep, with its lower margin moderately arcuate. Chela
slightly or a little longer than the carpus, somewhat more than twice as long as broad; anterior
distal corner of the hand not protruding, obtuse; movable finger considerably shorter than the anterior
margin of the hand and much narrower than the fixed finger, which has distinct, sharp teeth on the
distal half of the inner margin.

Second (fig. 6b) and third pairs of thoracic legs moderately strong; posterior spine on fourth
joint and both distal spines on fifth joint long; fifth joint only as long as the fourth; sixth joint more
than half as long again as fifth joint, but a little shorter than seventh joint with claw. — Three
posterior pairs of legs somewhat slender; sixth joint at least somewhat shorter than seventh joint
with claw, and the claw as long as or shorter than seventh joint.

Abdomen cylindrical, as long as the sum of the two posterior thoracic segments. The lower

88 CRUSTACEA MALACOSTRACA. II.

margin of the five anterior segments (figs. 6d and 6e) a little convex. The pleopods generally wanting;
in a single specimen (from Stat.4) which seems to be a female without marsupium, I found rudi-
mentary pleopods (fig. 6e), each pleopod being a minute, a little oval plate. — The uropods moder-
ately long, distinctly shorter than the two posterior segments combined; the peduncle a little longer
than deep, considerably or much shorter than the first joint of the endopod; the two joints of the
endopod equal in length or the first a little longer than the second; the one-jointed exopod reaches
considerably beyond the end of the proximal joint of the endopod, but not fully to the middle of the
distal joint.

Length of specimens with or without marsupium 1.7—1.9™™.

Subadult Male. The four-jointed antennule (fig. 6f) considerably thicker than in the female,
with first joint scarcely or distinctly less than twice as long as deep. Pleopods nearly as in Z. manca;
the outer remus is considerably or much longer than the oblong peduncle; the terminal sete as long
as or a little longer than the rami. — Length 1.4™".

Remarks. This small and extremely slender species is easily distinguished from allied forms
of this group by the shape of the body and the length of the exopod of the uropods.

As in the Norwegian species of Lepfognathia the mandibles of Z. swbegualis have the molar
process tapering to the acute end and besides distally curved.

Occurrence. This species has been taken by the “Ingolf” at six localities.

Davis Strait: St. 32: Lat. 66°35’ N., Long. 56°38’ W., 318 fm., temp. 3.0°; 6 spec.

West Greenland: Mouth of Ameralik Fjord, near: Godthaab, at Lat. 64°11' N., 5—7o fm.,

shells; 16 spec.

East of Iceland: St. 4: Lat. 64°o7'N., Long. 11°12’ W., 237 fm., temp. 2.5°; 7 spec.

— - — St. 58: Lat. 64°25’ N., Long. 12°09' W., 211 fm., temp. 0.8°; 2 spec.

North of the Feeroes: St. 139: Lat. 63°36’ N., Long. 7° 30 W., 702 fm., temp. + 0.6°; 35 spec.

—- - - — St. 141: Lat. 63°22'N., Long. 6°58’ W., 679 fm., temp. -+ 0.6°; I spec.

This distribution is interesting, as the species has been taken both in the cold area with a
temperature of + 0.6° and in temperatures above zero, even + 3.9°; furthermore it occurred near land
at a locality where the greatest depth was only 70 fathoms and at another station it was hauled up

from 702 fathoms.

56. Leptognathia tenella n. sp.
(Pl. TX, figs. ra—re.)

Female (without marsupium). Body slender, the largest specimen about eight times as long
as broad (fig. 1a), seen from above nearly cylindrical, with the lateral margins of the thoracic seg-
ments slightly convex and the abdomen tapering a little from the base to the end. — Carapace much
shorter than the two anterior segments combined, seen from above slightly more than half as broad
at the front end as behind the middle, not much longer than broad, with the lateral margins some-
what convex and the frontal process somewhat feebly developed.

Antennule (fig. 1b) only a little shorter than the carapace, very characteristic. First joint as
long as the three other joints combined, about two and a half times as long as deep, with the

CRUSTACEA MALACOSTRACA. II. 89

proximal third considerably thickened downwards. Second joint much produced above, very long,
having the upper margin distinctly more than half as long as that of the first joint, somewhat longer
than the two distal joints combined and more than twice as long as the depth of the joint; third
joint extremely short; fourth joint considerably shorter than the second which is about as long as the
terminal sete. Antenne somewhat short; fourth and fifth joints completely fused, together conspic-
ously less than twice as long as sixth joint.

Chelipeds (fig. 1b) moderately robust. The basal joint is a little shorter than the carpus, its
posterior process long, almost twice as long as deep with the end somewhat distant from the front
- lower end of second thoracic segment. Carpus a little less than twice as long as deep, with each of
the two halves of the lower margin somewhat feebly convex. Chela a little longer than the carpus,
a little more than twice as long as broad, presenting a somewhat peculiar aspect, because the posterior
margin is conspicuously convex; no protruding angle above the insertion of the movable finger, and
this finger is considerably shorter than the anterior margin of the hand and rather broad towards the
base; the fixed finger -has an acute tooth near the end of the incisive margin.

Second and third pairs of thoracic legs (fig. 1b) somewhat robust; fourth joint with the posterior
spine rather long; fifth joint a little shorter than the fourth, with the distal anterior spine long and
much longer than the posterior; sixth joint not fully twice as long as the fifth and distinctly longer
than seventh joint with its claw. — Three posterior pairs of legs moderately robust (fig. 1c); the spines
on fifth and sixth joints long; sixth joint somewhat shorter than seventh with its straight claw.

Abdomen as long as the two preceding segments combined; the sixth segment (figs. 1d and re)
a little longer than the sum of the three preceding segments, thus a little longer than in the other
species of this genus; this segment is somewhat produced behind, so that the uropods are inserted at,
or even slightly before, the middle of its lateral margins, an arrangement producing a peculiar aspect.
The lower margin of each of the five anterior segments either somewhat convex or even showing a
somewhat low protuberance. — Uropods strong and considerably shorter than the sixth segment,
reaching somewhat beyond the end of abdomen; peduncle much deeper than long; first joint of the
endopod only half as long as the second, but yet a good deal longer than the small, one-jointed exopod.

Length of the largest specimen 1.7™™.

Remarks. This species is easily recognized by the terminal part of the abdomen with its
last segment produced posteriorly and the characteristic uropods originating at the middle of the
lateral margins of the segments; the shape of the body, the antennule, the chelipeds afford further
characters. — Mouth-parts unknown.

Occurrence. It has been taken by the “Ingolf” at a single station.

Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°0o' W., 1199 fm., temp. 2.4°; 3 spec.

57. Leptognathia ventralis n. sp.
(Pl. VIII, figs. 7a—7k.)
Female. Body slender (fig. 7a), about seven times as long as broad, decreasing somewhat in

breadth from the carapace to the end of abdomen. — Carapace as long as, or even slightly longer
The Ingolf-Expedition, III. 3. I2

go CRUSTACEA MALACOSTRACA., II.

than, the two following segments combined, considerably longer than broad, anteriorly a little more
than half as broad as behind the middle, with the frontal process small and the posterior two-thirds
of the lateral margins rather convex. .

Antennule (fig. 7b) considerably shorter than the carapace, moderately slender; first joint
somewhat shorter than the three other joints combined, a little more than twice as long as deep,
with the proximal third somewhat thickened downwards; second joint distinctly more than half as long
as the first, not much produced above and about twice as long as deep; third joint as long above as
below and slightly more than half as long as the second; fourth joint a little shorter than second,
somewhat shorter than a couple of the terminal sete. — Antennze with fourth and fifth joints com-
pletely fused, together about three times as long as sixth joint.

Chelipeds (fig. 7b) moderately strong. The basal joint considerably shorter than the carpus;
its posterior process deeper than long, and its free hind margin reaches almost or fully to the anterior
lower end of the second segment. Carpus somewhat long, about twice as long as deep, with the
lower margin somewhat convex. Chela slightly or somewhat longer than the carpus, somewhat more
than two and a half times as long as broad; no protruding angle above the movable finger, which is
slightly shorter than the anterior margin of the hand and moderately broad; fixed finger with a tooth
near the end.

Thoracic segments, seen from above (fig. 7a) somewhat peculiar. Second segment short, very
much shorter than the third and decreasing much in breadth backwards. Third to sixth segments each
with the antero-lateral angles somewhat protruding and rounded, the lateral margins with the anterior
half distinctly concave, at or behind the middle a little protruding and then converging much to the
front margin of the next segment; seventh segment in the main of the same shape, but the convex
part of the lateral margin is situated more backwards and is more protruding. Anterior ventral part
of second segment produced in a conical, oblique process directed forwards and downwards, generally
large and acute (as in the subadult male, fig.7i), but in a couple of females (one of which with
marsupium) the process is smaller with the end obtuse (fig. 7b). — Thoracic legs somewhat slender
and long. Second and third pairs with rather long or long distal spines on fourth and fifth joint
(figs. 7b, 7e and 7h); sixth joint varies in length, being from a little shorter (fig. 7h) to somewhat or
considerably longer than fifth joint (figs.7b and 7e), but it is always somewhat shorter than seventh
joint with claw. Three posterior pairs (fig. 7f) with the spines on fifth and sixth joint long and sixth
joint shorter than seventh with claw.

Abdomen as long as the two preceding segments combined. Five anterior segments with
their lower margin rather convex (fig. 7g); pleopods entirely wanting. Sixth segment not quite as
long as the three preceding segments combined, seen from above (fig. 7a) with the portion between
the uropods broadly triangular, acute. — Uropods slender and somewhat long, longer than the two
posterior segments combined (fig. 7g); peduncle much longer than deep, but considerably shorter than
the proximal joint of the endopod; endopod with second joint distinctly longer than the first; the
exopod thin and more than half as long as the first joint of the endopod but always somewhat
shorter than that joint.

Lengt of females with or without marsupium 2—2.1 ™™.

CRUSTACEA MALACOSTRACA. II. gi

Subadult Male. The antennule (fig. 7i) much thicker than in the female, nearly as long
as the carapace; first joint twice as long as deep; fourth joint conspicuously longer than in the
female and distinctly longer than second. Pleopods long, about as long as the last segment (fig. 7k)
and especially the exopod is long in proportion to the peduncle, but the terminal sete are only about
half as long as the exopod. — Length 1.5—1.7 ™™.

Remarks. JZ. ventralis is somewhat allied to LZ. manca and L. subequalis but easily separated
by the shape of the thoracic segments, by the uropods and by the ventral process on second thoracic
segment.

The mandibles of Z. ventralis (fig. 7c) differ materially in the shape of the molar processes
from those in the species figured by Sars. The molar process of left mandible (Z) is subcylindrical,
its end cut off obliquely and furnished with about six triangular, obtuse teeth along the major part
of the terminal margin and some four slender teeth at the posterior part of that margin; the molar
process of the right mandible has in the main the same shape, but its oblique end has few and feeble
teeth and besides a single spine.

Occurrence. It has been taken by the “Ingolf” at four stations.

South of the Davis Strait: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870 fm., temp. 1.3°; I spec.

South of Iceland: St. 64: Lat. 62°06’ N., Long. 19°00’ W., 1041 fm., temp. 3.1°; 1 spec.
East of Iceland: St. ror: Lat. 66°23’ N., Long. 12°05’W., 537 {m., temp. + 0.7°; 1 spec.
Jan Mayen: ‘St. 115: Lat. 70°50’ N., Long. 8°29’/W., 86fm., temp.o.1°; 22 spec.

This occurrence is somewhat astonishing. It is seen that the depths of the four stations vary
from 86 to 1870 fathoms, the temperatures of the bottom from 3.1° to + 0.7°. In vain I have attempted
to find any valuable difference between the specimens from these stations. In the specimen from
Stat. 38 (1870 fm.) the sixth joint of second and third pairs of legs is a little shorter as compared with
fifth joint, the spines on fourth to sixth joint are longer and the uropods slightly longer than in the

specimens from Stat. 115, but these differences seem to me to be insufficient as specific characters.

58. Leptognathia acanthifera un. sp.
(Pl. IX, figs. 2a—d).

Female (without marsupium). Somewhat slender (fig. 2a) a little less than seven times as
long as broad, but decreasing considerably in breadth from second thoracic segment to the end of
abdomen. — Carapace almost as long as the two following segments combined, anteriorly a little
more than half as broad as behind the middle and with the posterior two-thirds of the lateral margins
rather convex.

Antennulee (fig. 2b) somewhat short, considerably or much shorter than the carapace, somewhat
robust. First joint almost as long as the three other joints combined, nearly half as deep as long;
second joint scarcely half as long as the first, not much produced above; third joint distinctly longer
than deep, with the upper margin a little more than half as long as that of second joint; fourth joint
somewhat shorter than the second and somewhat shorter than its terminal sete. — Antenne without

any vestige of an articulation between fourth and fifth joint.

12*

92 CRUSTACEA MALACOSTRACA. II.

Chelipeds (fig. 2b) moderately strong. The basal joint somewhat large, a little shorter than the
carpus, with the posterior protuberance well developed and the free rounded hind margin a little in
advance of the front lower end of second thoracic segment. Carpus a little more than twice as long
as deep, with its lower margin rather feebly curved. Chela somewhat longer than the carpus, almost
two and a half times as long as broad; movable finger somewhat robust, as long as the anterior
margin of the hand.

Thoracic segments, seen from above (fig. 2a), with the lateral margins somewhat angular; on
second to fourth segment the angles are situated before the middle and more or less rounded, on
fifth and sixth segment the angles are respectively a little and somewhat behind the middle and
moderately sharp, while on seventh segment no angle but a rounded protuberance is seen on each
side near the posterior margin. Second segment somewhat or considerably shorter than the third,
without any ventral process, but second, third and fourth segments have their lateral margins behind
the insertion of each leg produced in a somewhat broad, oblong, acute process (fig. 2 b) directed down-
wards and distally curved forwards; the processes on second segment are somewhat large and larger
than those on the two other segments; the processes are not visible when the animal is seen trom
above. — Thoracic legs (figs.2b and 2c) somewhat long and slender, with sixth joint distinctly shorter
than seventh with claw. Second and third pairs (fig.2b) subequal; posterior spine of fourth joint
rather long; fifth joint about as long as the fourth, with its two distal spines of very moderate length.

Abdomen as long as seventh, sixth and half of fifth segment combined, decreasing distinctly
in breadth backwards; sixth segment shorter than the three preceding segments combined but only a
little shorter than broad, broadest at the middle, and with the proximal part of the lateral margins
somewhat concave. Ventral margin of the five anterior segments somewhat convex (fig. 2d); no
pleopods. — Uropods (fig. 2d) slender, about as long as the sum of the two posterior segments; ped-
uncle a little longer than deep; endopod with second joint distinctly longer than the first; exopod
slightly more than half as long as first joint of the endopod.

Length of the largest specimen 1.7™".

.Remarks. JZ. acanthifera is easily separated from all other species by the lateral processes of
second to fourth segment; furthermore the antennulz are somewhat short and the uropods characteristic.

Occurence. Taken by the “Ingolf” at a single deep-sea station.

Davis Strait: St. 36: Lat. 61°59’ N., Long. 50° 21’ W., 1435 fm., temp. 1.5°; 3 spec.

Group c, subdivision P (vid. p. 85).

59. Leptognathia breviremis Lilljeborg.
Pl. IX, figs. 3a—3 g).
1864. Zanais breviremis Lilljeborg, Bidrag til kannedomen om de inom Sverige och Norrige
forek. Crust. of .... Tanaidernas familj, p. 21 (Female).
11896. Leplognathia breviremis G.O.Sars, Account Crust. Norway, Vol. II, p. 28, Pl. XIII, fig. 1.
Female. Though Sars has published a good description with figures of this form, it may be
useful to point out a number of features,

CRUSTACEA MALACOSTRACA., II. 93

* The antennule (fig. 3a) are moderately stout and considerably shorter than the carapace.

First joint neatly as long as the other joints combined, scarcely or distinctly more than twice as long
as deep; second joint nearly half as long as the first and considerably produced above; third joint
with its upper margin very short; fourth joint a little shorter than second, with its terminal sete
somewhat long. — Antennulz with the articulation between fourth and fifth joint indistinct or moder-
ately distinct.

Chelipeds somewhat long and moderately slender (fig.3a). Basal joint normal, somewhat long
but yet somewhat shorter than the carpus, and the posterior margin of the protuberance reaches about
the front angle of second thoracic segment. Carpus slightly or scarcely more than twice as long as
deep, with its lower margin almost straight. Chela scarcely as long as the carpus, somewhat more
than twice as long as broad; hand uncommonly long, with the anterior margin almost half as long
again as the movable finger and with only a single seta at the hind margin at the base of the fixed
finger, which has at least the distal tooth of the incisive margin triangular and well developed.

Thoracic legs moderately slender; sixth joint about as long as or, especially in the posterior
pairs, a little longer than seventh with claw. Second (fig.3a) and third pairs have the fifth joint at
least not longer than the fourth but much shorter than the sixth, and the sete of moderate length.

Abdomen (figs. 3b and 3c) has the ventral margin serrate, as each of the five anterior segments
has a well developed, oblique, triangular or distally obliquely cut, conspicuous process. Sixth segment
not fully as long as the sum of the three preceding segments. Pleopods somewhat short and broad,
with the sete well developed and some of these longer than the rami. — Uropods short, in smaller
specimens somewhat, in large specimens considerably or much, shorter than the last segment; endopod
with first joint conspicuously shorter than, or about as long as, the second; exopod a little or some-
what shorter than the endopod.

Length of one of the largest specimens without marsupium (from the “Ingolf” Stat. 38) 1.8 ™",
of an ovigerous female (from Stat. 117) 1.4", of an ovigerous female from Norway 1.3 ™".

Subadult Male. Antennule as usually considerably thicker and the pleopods somewhat
longer than in the female.

Adult Male (figs. 3d—3g). Antennulz 7-jointed; the two proximal joints very thick and the
upper margin of first joint about half as long again as that of the second; third and fifth joints quite
short, fourth joint extremely short, these three joints taken together not quite as long as the second;
fourth and fifth joints each adorned with very long sensory filaments; sixth joint either conspicuously
longer than, or only as long as, the three preceding joints combined, at the lower distal angle with a
bundle of shorter sensory sete, and either a little longer or even a little shorter than seventh joint,
which terminates in two strong sete and a sensory hair. — Antenne only as long as the upper
margin of the two proximal antennular joints, terminating in an extremely long seta.

Chelipeds (fig. 3) long and moderately slender; carpus twice as long as deep. Chela considerably
longer than the carpus, somewhat less than three times as long as broad; hand elongate, with the
anterior margin half as long again as the movable finger, which is slender, while the fixed finger is
broad at the base and its incisive margin éxtremely finely serrate, a feature visible only under high

magnifying power.

94 CRUSTACEA MALACOSTRACA. II.

Thoracic segments as usually short, together even less than twice as long as the carapace.
Seventh segment with a large, obliquely triangular ventral process. — Thoracic legs long and slender;
second (fig.3d) and third pairs with the sixth joint almost half as long again as the fifth and scarcely
longer than seventh with claw. Fifth pair with seventh joint plus claw considerably longer than sixth
joint, while in the two posterior pairs (fig.3e) the difference in length between the same parts is
somewhat small.

Abdomen (fig. 3 f) extremely long, about twice as long as the six thoracic segments combined;
the five anterior segments each with an obliquely triangular ventral process, which is large on first
segment, and the processes decrease gradually in size from first to fifth segment, so that that of the
last-named segment is quite low. Pleopods long with extremely long sete. Sixth segment about as
long as the two preceding segments combined, posteriorly produced in a triangular, acute process. —
Uropods inserted before the middle of their segment and reaching somewhat beyond its end; endopod
three-jointed and last joint a little (fig. 3g) or somewhat (fig. 3f) shorter than the two others combined;
exopod one-jointed, very slender, slightly longer than the first joint of the endopod.

Length 1—1.1™.

Remarks. The female and subadult male of Z. breviremis are easily distinguished from all
other species of the genus excepting Z. crassa n. sp. by the thick body, the short uropods, ete. By the
rather slender carpus “and the slender chela with its proportionately long hand it can be separated
from Z. crassa. The adult male was hitherto unknown. .

Occurrence. This species has been taken by the “Ingolf” at fifteen stations.

Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 2 spec.

_ = St. 36: Lat. 61°50’ N., Long. 56°21’ W., 1435 {m., temp. 1.5°; 20 spec.,
2 of which are adult males.

South of Davis Strait: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870fm., temp. 1.3°; 6 spec.

South of Iceland: St. 64: Lat. 62°06'N., Long. 19°00’ W., 1041 fm., temp. 3.1°; 1 spec.

North of the Feroes: St. 141: Lat. 63°22'N., Long. 6°58’ W., 679 fm., temp. + 0.6°;

large number of specimens.
— - - — St. 139: Lat. 63°36'N., Long. 7°30’ W., 702 {m., temp. + 0.6°;
large number of specimens.
East of Iceland: St. 105: Lat. 65°34'N., Long. 7°31'W., 762 im. temp. +0.8°; 4 spec.
— - — St. 103: Lat. 66°23'N., Long. 8°52'W., 579fm., temp. + 0.6°; 1 spec.
— - — St. 102: Lat. 66°23’ N., Long. 10°26' W., 750fm., temp. + 0.9°; ab. 30 spec.

— — St. ror: Lat. 66°23'N., Long. 12°05’ W., 537{m., temp. +0.7°; 8 spec.,

one of which is an adult male.

North of Iceland: St. 125: Lat. 68°08’ N., Long. 16°02’ W., 729 fm., temp. + 08°; 8 spec.

North-East of Iceland: St. 120: Lat. 67°29' N., Long. 11°32’ W., 885 fm., temp. + 1.0°; 6 spec.

— - oo St. 119: Lat. 67°53’ N., Long. 10°19’ W., 1o1ofm., temp. + 1.0°; 33 spec.

South of Jan Mayen: St. 118: Lat. 68°27'N., Long. 8°20’ W., 1060 fm., temp. + 1.0°; 1 spec.

ies (2 EOE) Sh —_ St.117: Lat. 69°13’N., Long. 8°23' W., 1003 fm., temp. + 1.0°;

large number of specimens.

CRUSTACEA MALACOSTRACA. II. 95

Distribution. Lilljeborg established Z. breviremts on specimens taken at Bohuslan, 50—60
fathoms, and at Molde (the western coast of Norway, at Lat. 62°45’ N.), 4o—50 fathoms. Sars possessed
it from Christiania Fjord, 20—60 fathoms, and from several places on the South and West coasts of
Norway, northwards to Kvalo, at Lat. 70°40’ N. In 1910 I mentioned it from two places in the Kattegat,
15 and 17 fathoms and from a place in Skager Rak, 125 fathoms. Besides the species has been taken
between Norway and the Orkneys, 150 fathoms (Internat. Investig.), at some places on both sides of
Scotland, f.inst. near Aberdeen, 45 fathoms, and in Loch Fyne pelagically in a vertical haul (T. Scott),
_ furthermore off Northumberland (G.S. Brady), at Plymouth (A.M. Norman) and off West Ireland, 320
- fathoms (Tattersall).

The perusal of the preceding lines and of the “Ingolf” stations shows the bathymetrical occur-
rence to be extremely remarkable. In vain I have attempted to find any difference worth mentioning
between females from 1870 fathoms in the warm area, from 1003 fathoms in the cold area and Nor-
wegian specimens from 20—60 fathoms presented by Sars. To begin with I had believed that the
specimens from the “Ingolf’ belonged to a species different from the Z. dveviremis occurring at Den-
mark and Norway, but after a detailed examination I was forced to abandon that opinion, as I could
not find any other difference than that the uropods seem to be a little longer and sixth abdominal
segment a little less highly vaulted in the Norwegian specimens (fig. 3c) than in specimens from the

deepest “Ingolf? stations.

60. Leptognathia crassa n. sp.
(Pl. IX, figs. 4a—qe.)

Female (without marsupium). Body uncommonly robust (fig. 4a), from four and a half to
slightly more than five times as long as broad, seen from above subcylindrical, with the abdomen
slightly narrower than the thorax and the lateral margins of the thoracic segments slightly convex.
— Carapace a little shorter than the two following segments combined (fig. 4a), slightly broader than
long and at the anterior end about half as broad as a little from the base; frontal process feebly
developed, short, broad, acute. i

Antennulee (fig. 4b) only a little shorter than the carapace. First joint a little shorter than
the other joints combined, robust, not fully twice as long as deep and somewhat produced above;
second joint thick, distally much produced above, with the upper margin as long as the depth of the
first joint; third joint with the upper margin very short; fourth joint slightly shorter than the upper
margin of the second, slender and subcylindrical, with the terminal setee somewhat long. — Antenne
with fourth and fifth joints completely fused, and this fourth joint only half as long again as the
penultimate joint.

Chelipeds robust (fig. 4b). Basal joint thick, with the free hind margin of the posterior pro-
tuberance reaching to second thoracic segment. Carpus somewhat longer than the basal joint, ovate,
somewhat or considerably less than twice as long as deep, with the free lower margin distinctly, the
upper margin strongly convex. Chela slightly longer than the carpus, somewhat more than twice as
long as broad; the hand with two strong sete on the posterior margin at the base of the movable

finger and its anterior margin only a little longer than the movable finger.

96 CRUSTACEA MALACOSTRACA. II.

Thoracic segments subrectangular (fig. 4a) with their lateral margins slightly convex; third
segment conspicuously less than half as long again as the second. — Legs of middle length (figs. 4b
and 4c), and seventh joint with claw a little longer than sixth joint. Second and third pairs with
sixth joint about as long as fifth plus half of the fourth and the setee somewhat short; three posterior
pairs (fig. 4c) with some of the setee rather long.

Abdomen deep (fig. 4d) and as long as the sum of the three posterior thoracic segments; the
ventral serration is low and feebly developed, but the margin of each segment shows a sharp angle.
Pleopods small, but both rami with some well developed sete about as long as the rami (fig. 4).
Sixth segment, seen from above (fig. 4a), as long as the sum of the three preceding segments and
posteriorly broadly rounded. — Uropods (figs. 4d and 4e) only about half as long as their segment;
peduncle deep; endopod with first joint almost as deep as long, thicker and much shorter than second
joint and as long as, or slightly shorter than, the thin exopod.

Length of the largest specimen, a female without marsupium, 1.9™™.

Remarks. JZ. crassa is similar to ZL. breviremis, but differs in several particulars. The an-
tennulz have the two proximal joints conspicuously thicker, but the fourth joint slender and cylindrical
instead of conical. The chelipeds are much more robust with the carpus considerably deeper, the hand
shorter in proportion to the movable finger than in Z. breviremis and two strong sete instead of one
at the posterior base of the fixed finger. The abdomen has the ventral serration much less developed
and the pleopods and uropods are distinctly smaller than in the other species.

Occurrence. Taken by the “Ingolf” at its deepest station.

South of Davis Strait: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870 fm., temp. 1.3°; 6 spec.

It may be added that after I had discovered the six specimens of this species between the
specimens of ZL. breviremis from the same station, I looked in vain for more specimens among the

numerous specimens of the last-named species from the other fourteen “Ingolf” stations.

Group c, subdivision ; (Vid. p. 85).

61. Leptognathia polita un. sp.
(Pl. IX, figs. 5a—5f)

Female (without marsupium). Moderately robust (fig.5a), about six and a half times as long
as broad and seen from above subcylindrical, yet with the carapace and the middle of abdomen slightly
broader than the thoracic segments, which have their lateral margins almost straight, being curved
only at both ends of each segment. — Carapace slightly longer than the sum of the two next seg-
ments, seen from above (fig. 5a) nearly hexagonal and broadest considerably before the middle, where
each lateral margin has a pronounced angle, and from these angles the margins converge slightly to
the base and strongly to the front end, which is conspicuously less than half as broad as the carapace
between the angles mentioned; frontal process low, rounded.

Antennulee (fig. 5b) much shorter than the carapace and rather slender. First joint almost as
long as the other joints combined, two and a half times as long as deep; second joint considerably

produced above, half as long as the first and above a little more than twice as long as deep; third

CRUSTACEA MALACOSTRACA. II. 97

joint with the upper margin half as long as that of second joint and conspicuously longer than the
depth of the joint; fourth joint considerably shorter than the second and its longest terminal seta
longer than the two distal joints combined. — Antennz only a little shorter than the antennule, with
fourth and fifth joints well separated.

Chelipeds (figs. 5b and 5c) strong and very curious. Basal joint nearly deeper than long; the
posterior protuberance is, seen from the side, small, about as long as deep and with only the lower
margin free, while even the posterior end is situated somewhat before the middle of the cephalothorax;
the area between the hind margin of the basal joint and the thinner integument behind the cephalo-
thorax is large, oblong, more than twice as long as deep and well separated by a thin-skinned, hori-
zontal ridge from the carapace. The carpus, though a good deal longer than the basal joint with posterior
protuberance, is short and deep, being less than half as long again as deep, with the upper margin
very convex and the lower peculiarly hollowed. Chela somewhat longer than carpus and twice as
long as broad; anterior margin of the hand distinctly shorter than the movable finger, which is very
thick towards the base (fig. 5c) with its incisive margin very sinuate, having a broad, oblong-triangular
protuberance before the middle; fixed finger with two tubercles on the incisive margin, the proximal
being somewhat small though very distinct, the distal large, much broader than high, rounded; two
sete on the posterior margin of the hand, and the end of both fingers obtuse.

Second thoracic segment somewhat shorter than the third (fig. 5a); all segments transverse
and all, excepting the seventh, subquadrangular with the angles rounded. — Thoracic legs uncom-
monly short. Second (fig. 5d) and third pairs moderately slender; distal spines on fourth and fifth
joints moderately long; sixth joint somewhat longer than the fifth and a little longer than seventh
with claw; the claw a little more than half as long as seventh joint.

Abdomen somewhat shorter than the three preceding segments combined (fig. 5a). Five anterior
segments each with a rounded, moderately large ventral protuberance; pleopods moderately small and
their rami with somewhat long sete (fig. 5f). Sixth segment about as long as the three preceding
segments combined. — Uropods a little shorter than their segment, somewhat robust; peduncle longer
than deep; first joint of the endopod a little longer than the second and somewhat longer than the
one-jointed exopod. ‘

The body of the animal is polished, shining, yellowish, and the fingers of the chelz are deep
reddish yellow.

Length of the single probably full-grown specimen 3.2™™.

Remarks. This species is moderately large and easily distinguished from all other forms of
the genus excepting Z. vicina n. sp. by its shape, colour, uropods, etc., but especially by the peculiar
development of the chelipeds, which originate before the middle of the cephalothorax. The differences
between Z. polita and L. vicina are pointed out in the “Remarks” on the latter species.

Occurrence. This species has been taken by the “Ingolf” at a single station.
North of the Feeroes: St. 141: Lat. 63°22’ N., Long. 6°58’ W., 679 fm., temp. + 0.6°; 1 probably

full-grown specimen and 1 juvenile specimen without seventh pair of legs.
The Ingolf-Expedition. IIL. 3. 13

98 CRUSTACEA MALACOSTRACA. II.

62. Leptognathia vicina n. sp.
(Pl. IX, figs. 6a—6i.)

Female. Moderately robust (fig.6a), from six to seven times as long as broad and seen from
above subcylindrical, yet with the carapace and the middle of abdomen from slightly to distinctly
broader than the thoracic segments. — Carapace nearly as long as, or slightly longer than, the two
following segments combined (fig. 6a), seen from above less or more distinctly hexagonal and sub-
similar to that of Z. ota, but the broadest place is only a little before the middle; frontal process
small, acute.

Antennule (fig.6b) much shorter than the carapace and moderately slender. First joint some-
what shorter than the three other joints combined, a little more than twice as long as deep; second
joint distally moderately produced above, with its upper margin half as long as the first joint but not
quite twice as long as the depth; third joint above slightly more than half as long as the second;
fourth joint a little shorter than the second and not much shorter than its terminal sete. — Antenne
as long as the three proximal antennular joints combined, with fourth and fifth joints well separated
and fifth joint half as long again as the fourth, which is slightly longer than the sixth.

Chelipeds (figs.6b and 6f) somewhat similar to those in Z. Jolita, but yet showing some differ-
ences. Basal joint about as long as deep, with the posterior protuberance, seen attached to the animal
and from the side, not only somewhat short but low — when the cheliped has been removed and
pressed a little under a glass-cover that protuberance shows itself to be a good deal broader (fig. 6f)
because its lower part, which on the animal turns downward, then becomes visible. The area between
the basal joint and the thin integument behind the cephalothorax is large, a little more than twice as
long as deep, but the hind margin of the posterior protuberance is yet situated a little behind the
middle of the cephalothorax. Carpus much longer than the basal joint, conspicuously less than half
as long again as deep, and its lower margin has a conspicuous protuberance bearing two sete. Chela
as long as the upper margin of carpus plus the basal joint and a little more than twice as long as
broad; anterior margin of the hand a little longer than the movable finger, which is very thick
towards the base, but its incisive margin has its proximal half a little concave and without any pro-
tuberance before the middle; the fixed finger has on the incisive margin a feeble proximal and a
more oblong and conspicuous though rather low distal protuberance.

Thoracic segments (fig. 6a) transverse with their lateral margins a little convex or rather sub-
angular and as usually in such cases second to fourth segments are broadest before the middle, the
other segments broadest gradually more and more behind the middle. Second thoracic segment some-
what or considerably shorter than the third. — Thoracic legs of moderate length; second (fig.6b) and
third pairs in the main as in Z, folita, but seventh joint with claw as long as or a little longer than
sixth joint. Three posterior pairs (fig. 6g) in the main as in L. Aolta, but sixth joint almost longer
than the seventh joint with its somewhat short claw.

Abdomen somewhat shorter than the three preceding segments combined (fig. 6a). Ventral side
of the five anterior segments (fig. 6h) with rounded moderate protuberances; the moderately small

pleopods and their sete also nearly as in LZ. Jolita. Sixth segment somewhat shorter than the sum

CRUSTACEA MALACOSTRACA. IL. 99

of the three preceding segments. — Uropods (fig.6h) a little longer than sixth segment, somewhat
robust; peduncle thick, only a little longer than deep; endopod with first joint a little longer than the
second and considerably longer than the exopod.

The animals are whitish or light yellowish and less shining than in Z. polita.

Length of females with marsupium 2.7—3™™., of a very large female without marsupium 3.3 ™™.

Subadult Male. The antennule (fig.6i) are considerably thicker than in the female; first
joint only slightly longer than second and third joints combined, about twice as long as deep; second
joint only a little less deep than the proximal part of the first joint and conspicuously less than half
as long again as deep. — Abdomen longer than in the female, slightly longer than the three preceding
segments combined. Pleopods larger and especially the exopods conspicuously longer with longer
setee than in the females. — Length 2.4—3.0™™.

Remarks. JZ. vicina is allied only to LZ. pfolita; the best distinguishing characters between
them are afforded by the joints of the chelipeds and by the much feebler armature of the incisive
margins of the fingers of the chele in Z. vcimna.

The mouth-parts have been examined. The mandibles (fig.6c) are slender and their molar
processes are very different from those in the species of Leptognathia figured by Sars. Each molar
process has the proximal half somewhat thicker than the distal; the end is rounded with three
triangular teeth in front (fig.6d) and posteriorly with several slender processes forming a comb.
The maxillule (fig.6e) are very slender, but the major part of the palp is somewhat inflated.

Occurrence. JZ, vicima has been taken by the “Ingolf’ at two stations.

Davis Strait: St. 32: Lat. 66°35’ N., Long. 56°38’ W., 318 fm., temp. 3.9°; 1 spec.

— — St. 28: Lat. 65°14’ N., Long. 55°42’ W., 420fm., temp. 3.5°; 40 spec.
Besides it has been taken by Admiral C. Wandel in 1889 at the following place.
Davis Strait: Lat. 66°49’ N., Long. 56°28’ W., 235 fm., sand and ooze, temp. 4.4°; I spec.

Group d. Uvropods with the peduncle produced in a triangular protuberance probably answering

to an exopod not marked off, endopod two-or oneyointed. Pleopods moderately well developed.
Species 63—65.

This group is a very natural one, as its ‘three species are allied to each other and differ in
several features from all species of this genus described in the preceding pages. The chelipeds differ
from those of all other species by the curiously shaped ischium and carpus; furthermore the basal
joint has the whole oblique posterior margin attached to the cephalothorax. The three posterior pairs
of legs are robust with seventh joint short and the claw very short.

63. Leptognathia profunda n. sp.
(Pl. X, figs. ra—rh).

Female (without marsupium). Body slender, a little more than eight times as long as broad
(fig. 1a) and with the abdomen almost broader than the thorax or the carapace. Carapace as long as
the two following segments combined (fig. 1a), seen from above considerably longer than broad, feebly

angular before the middle and in front more than half as broad as near the middle.
13*

ba0,6) CRUSTACEA MALACOSTRACA. II.

Antennule scarcely or a little shorter than the carapace (fig. rb), moderately robust. First joint
only a little longer than second and third joints. combined, about twice as long as deep; second joint
a little more than half as long as the first and a little produced above; third joint moderately long,
with its lower margin as long as that of second joint; fourth joint almost as long as the second. —
Antenne with fourth and fifth joints completely fused.

Chelipeds (figs. 1b and 1c) moderately strong. Basal joint short, with its entire posterior
margin very oblique and attached to the lower part of the side of cephalothorax nearly at its middle,
thus very far from the lower front angle of second thoracic segment. Carpus half as long again as
deep, somewhat triangular in aspect, with its postero-inferior margin long; the anterior ‘margin
uncommonly short. Chela not longer than the carpus, somewhat curved, almost two and a half times
as long as broad with the posterior margin of the hand considerably concave; movable finger as long
as the anterior margin of the hand, moderately broad; fixed finger with its posterior margin straight
and with a single seta towards its base; this finger is somewhat broader than the movable and
decreases gradually in breadth from the base to somewhat from the end, where a conspicuous, triang-
ular tooth projects on the incisive margin, while the distal portion of the finger beyond that tooth is
slender, straight and projects conspicuously when the fingers are closed; the movable finger has a
long and strong sub-spiniform seta projecting from the inner side somewhat from the base; furthermore
a long seta and two shorter sete originate from the inner surface of the hand at the base of the
fixed finger; when the fingers are closed no interval is found between their proximal halves.

Thoracic segments with their lateral margins considerably convex (fig. 1a); second segment
somewhat shorter than the third. — Second to fourth pairs of thoracic legs (fig. 1b) moderately strong,
subsimilar in shape but decreasing considerably in length from second to fourth pairs; second pair
(fig.1d) with fourth and fifth joints subequal in length and their terminal sete short; sixth joint
somewhat longer than the fifth and as long as seventh joint with claw. Three posterior pairs (fig. re)
somewhat short and robust with their spines rather short; seventh joint short and the claw very short;
both together much shorter than sixth joint.

Abdomen somewhat longer than the two preceding segments combined (fig. 1 a). Ventral
margin of each of the five anterior segments somewhat convex. Pleopods somewhat large (fig. 1g);
both rami with a good number of plumose sete (fig. 1f) and many of them long; the sete are found
on the exopod along the whole, on the endopod along the distal half, of the outer margin. Sixth
segment as long as the two preceding segments combined. — Uropods somewhat shorter than sixth
segment; peduncle broad but distinctly longer than deep, with its lower produced part almost as long
as the upper margin of the peduncle and terminating in a long seta and two short sete (fig. 1h); the
endopod moderately robust, two-jointed, but the articulation is not very distinct; the second joint
scarcely as long as the first and with a dorsal seta at the middle.

Length 2.2 ™™,

Remarks. JL. profunda differs from all preceding species of the genus by the characters enumer-
ated for the group. Its differences from Z. datiremz's n. sp. are pointed out in the “Remarks” on this species.

Occurrence. It has been taken by the “Ingolf” at a single deep-sea station.

South-West of Cape Farewell: St. 22: Lat. 58°10’ N., Long. 48°25’ W., 1845 fm., temp. 1.4°; 3 spec:

CRUSTACEA MALACOSTRACA. II. IOI

64. Leptognathia latiremis un. sp.
(Pl. X, figs. 2a—2n).

Female (without marsupium) and subadult Male. Somewhat slender, about seven and a
half times as long as broad, seen from above sybcylindrical, but the lateral margins of the thoracic
segments considerably convex: — Carapace somewhat shorter than the two following segments com-
bined (fig. 2a), not much longer than broad, subquadrangular but with all angles broadly rounded.

Antennulz in the female only a little shorter than the carapace, somewhat varying in thickness
. (figs.2b and 2c). First joint somewhat longer than the two following joints combined, about two and
a half times as long as deep; second joint about half as long as the first and a little produced above;
third joint considerably shorter than the second, while fourth joint is conspicuously longer than the
second; in a subadult male the three proximal joints (fig. 2d) are considerably thicker in proportion to
length and the fourth joint is much longer than the second and only a little shorter than the first. —
Antenne with fourth. and fifth joints completely fused, about twice as long as the penultimate joint.

Chelipeds robust (fig. 2g). The basal joint as in Z. Jrofunda; ischium extremely broad, em-
bracing more than half of the lower margin of the carpus. Carpus extremely deep, less than half as
long again as deep. Chela a little longer than the carpus, twice as long as broad; the proximal
third of the posterior margin very concave and the major part distinctly convex, with two sete; the
fixed finger is peculiarly shaped, the incisive margin to a little from the end being very convex and
a little more than the distal half of this portion serrate with some more or less obtuse teeth; the
terminal small part of the finger is shaped as an oblong, almost straight tooth; the movable finger
is robust, but yet very conspicuously narrower than the proximal half of the fixed finger and consid-
erably shorter than the anterior margin of the hand; when the fingers are closed a conspicuous
strip of the movable finger is covered by the fixed finger, while at the base there may be seen a
minute hole between the fingers; the inner side of the hand bears a long, spiniform seta and a similar
seta originates from the inner surface of the movable finger.

Thoracic segments nearly as in Z. frofunda. All thoracic legs (figs. 2h—2k) in the main as in
L. profunda, but in the anterior pairs fourth and fifth joints are shorter in proportion to thickness,
sixth joint much longer than the fifth but slightly shorter than the seventh with claw.

Abdomen somewhat longer than the two posterior thoracic segments combined (fig.2a). Ple-
opods (fig. 21) with the rami well developed though smaller than in Z. profunda; each ramus with
setee only on the terminal margin and the sete are shorter than the rami and not plumose; in young
specimens with the last pair of thoracic legs still wanting the pleopods are also wanting (fig. 2n).
Sixth segment short, shorter than the two preceding segments combined and posteriorly broadly
rounded (fig. 2m); — Uropods as long as the sixth segment (figs.2m and 2n); peduncle broad but
distinctly longer than broad, produced in a triangular plate, which is as long as or longer than the
upper margin of the peduncle and its obtuse end bears one long and one short seta; endopod moder-
ately robust, without any vestige of a division into two joints.

Length of the largest specimen from Stat. 58 is 2.5™™, of the specimen from Stat. 24 2.8™™

Remarks. This species is distinguished from Z. glacialis especially by the shape of the fixed

102 CRUSTACEA MALACOSTRACA. II.

finger of the chele; from ZL. profunda it is distinguished by several features, among which may be
pointed out the quite different shape of the fixed finger of the chela and the short and not plumose
setee of the pleopods.

Fig. 2f represents the maxillipeds and fig.2e the mandibles of this species, The last-named
figure shows that the mandibles are somewhat thick and their molar processes decrease slightly in
thickness to the end, which is cut off very obliquely and adorned with about three teeth. The molar
processes differ therefore materially from those in the species figured by Sars and remind one more of
those in Z. ventralis as described on p.g1, though differing in the armature of their end.

Occurrence. ZL. latiremis has been taken by the “Ingolf? at three stations.

East of Iceland: St. 58: Lat. 64°25’ N., Long. 12°09’ W., 211 fm., temp. 08°; 12 spec, but the

majority juvenile without pleopods.

North of Iceland: St. 126: Lat. 67°19’ N., Long. 15° 52’ W., 293 fm., temp. + 0.5°; 1 juv. spec.

— — St.124: Lat. 67°40’ N., Long. 15°40' W., 495 fm., temp. + 0.6°; 1 spec.

65. Leptognathia glacialis n. sp.
(Pl. X, figs. 3 a—3b).

Female (without marsupium). This species, of which only a single specimen is at hand, is
closely allied to Z. datiremis, differing only in the shape of the chelz and a little in the uropods.
When the chela is seen vertically from the outer side (fig. 3a) it is observed, that the major part of
its posterior margin is considerably convex with two sete, the incisive margin a little sinuate and its
proximal half slightly concave with about seven rounded saw-teeth; the movable finger is very much
narrower than the proximal third of the fixed finger and has a minute tooth near the middle of its
incisive margin; when the fingers have their apical parts crossed a long and moderately broad
interval is found between their incisive edges. The uropods (fig.3b) have the produced part of the
peduncle considerably shorter and more rounded than in the two other species of group d.

Length of the specimen 2.8 ™™.

Occurrence. This species has been taken by the IIl¢ Amdrup Expedition at East Greenland
at a single locality.

Fleming Inlet: Lat. 71°51’ N., Long. 22° 27' W., 118 fm., redfclay; 1 spec.

Haplocope G. 0. Sars.

This genus, established on a single species, is so closely allied to Leptognathia, that it would per-
haps be advisable either to cancel it or to divide Leptognathia into several genera. On p.g and 65—66 I
have pointed out why I think it premature to subdivide the last-named genus, but as Hafplocope has
been established may years ago it might probably be nearly impossible to get it cancelled. Haplocope
angusta G. O. Sars is a slender species with long uropods and the exopod of these appendages two-
jointed; according to Sars it differs from Leptognathia in having the molar process of the mandibles

CRUSTACEA MALACOSTRACA. ILI. 103,

tather strong, cylindric and armed at the tip with dentiform tubercles, furthermore by having the
pleopods uniramous without sete. Dollfus has established a new species as Haplocope (?) abyssorum,
but according to his figures I suppose that this species, which has no rami on the pleopods, does not
belong to Haplocope, but either to Leptognathia or, and more probably, be the type for a new genus. —
From the “Ingolf’ I have a new species which is allied to H. amgusta in the mandibles (fig. 4c) and in
all other features of some importance excepting that the unimarous pleopods have very long sete. I

think that the best external character for Haplocope is that the pleopods are uniramous.

66. Haplocope linearis n. sp.
(Pl. X, figs. 4a—qf).

Female. Slender, between eight and eight and a half times as long as broad, tapering some-
what in breadth from the second thoracic segment to the end of abdomen (fig. 4a). — Carapace about
as long as second segment plus half of the third, slightly narrower than second segment, not much
longer than broad, about twice as broad behind the middle as at the front end and with the lateral
margins very moderately convex.

Antennule (fig.4b) much shorter than the carapace, somewhat robust. First joint somewhat
shorter than the other joints combined, not fully twice as long as deep; second joint not quite half as
long as the first and feebly produced above, only a little longer than the third and a little shorter
than the fourth joint; longest terminal setee about as long as the two distal joints combined. —
Antennze somewhat short, with fourth and fifth joints completely fused.

Chelipeds (fig. 4b) somewhat small. The basal joint with the posterior protuberance well devel-
oped, about as long as deep, with its rounded hind margin moderately distant from the lower front
angle of second thoracic segment. Carpus considerably longer than the basal joint, twice as long as
deep, with the lower margin considerably convex. Chela small, somewhat shorter than the carpus
and somewhat more than twice as long as broad; movable finger as long as the anterior margin of
the hand and towards the base much narrower than the fixed finger which has two long setz on its
straight posterior margin towards the hand.

The thoracic segments (fig.4a) more or less distinctly angular, and on the second segment
their lateral angles are situated far in front, on the following segments gradually more backwards,
consequently on the seventh segment only a little from the posterior margin. Third segment is more
than half as long again as the second, slightly longer than broad and slightly shorter than fifth
segment. — Thoracic legs slender and subequal in length, moderately long. Second pair (fig. 4b) with
fourth and fifth joints subequal in length and their terminal spines long; sixth joint not fully half as
long again as the fifth and a little shorter than seventh joint with claw. Three posterior pairs
(fig. 4d) with most of the spines moderately long and their sixth joint a little shorter than seventh
with claw.

Abdomen slightly shorter than the two preceding segments combined and the first segment
conspicuously narrower than the seventh thoracic segment. Five anterior segments with the ventral

margins considerably or very moderately convex (fig. 4f). Pleopods (figs.4e and 4f) long and narrow;

TOo4 -CRUSTACEA MALACOSTRACA. II.

peduncle very oblong; the single ramus half as long again as the peduncle, about four times as long
as broad, with the end cut off obliquely; on this terminal margin about seven fine, extremely long
setee are inserted, some of them about two and a half times as long as the ramus; no sete are found
on the lateral margins of the rami. Sixth segment as long as, or a little longer than, the two pre-
ceding segments together. — Uropods (fig. 4f) slender and long, from a_.little shorter to a little longer
than the three posterior segments combined; peduncle long, abotit as long as the fifth segment and
more than twice as long as deep; endopod with first joint a little or conspicuously longer than the
second; exopod very slender, half as long as the endopod and with its two joints equal in length.

Length of a female with marsupium 2™.

Remarks. This small and slender species is easily distinguished from all North Atlantic or
Arctic forms hitherto known by its long and uniramous pleopods with very long sete.

The mandibles are shown in fig.4c; a description is scarcely needed beyond that given in the
remarks on the genus.

Occurrence. Taken by the “Ingolf” at a single station.

Davis Strait: St. 25: Lat. 63°30’ N., Long. 54°25’ W., 582 fm., temp. 3.3°; 12 spec.

Leptognathiella n. gen.

This genus is established on a new species which in a few features differs materially from
Leptognathia and Haplocope.

The body is extremely slender. The four-jointed antennule differ from those of Leptognathia
by having the second joint strongly produced above (Pl. X, figs. 5b and 5g) into a triangle overlap-
ping a part of third joint; besides second joint, seen from the side (figs. 5d and 5g), increases in depth
from the base to beyond the middle. (Mouth-parts unknown). Chelipeds normal, with the basal joint
having the hind margin of the well developed posterior protuberance free and rounded. Thoracic
legs built as in Leptognathia, short; three anterior pairs thick. Pleopods wanting in the female. Last
abdominal segment with the posterior margin between the uropods feebly concave (fig. 5c); uropods
extremely long, curved downwards, biramous (figs. 5f and 5i), with the endopod two-jointed, the short
exopod one-jointed.

Remarks. Though the characters pointed out as generic are not very valuable, the aspect
of the animal is so different from that of the forms of Lep/ognathia that the establishment of a new

genus seemed to me to be necessary.

67. Leptognathiella abyssi n. sp.
(Pl. X, figs. 5a—5i).
Female (without marsupium). Body extremely slender, between ten and nine and a half
times as long as broad (fig. 5a), broadest at the middle of the thorax which is a little broader than
the carapace and somewhat broader than the abdomen. — Carapace about as long as the second plus

CRUSTACEA MALACOSTRACA. II. 105

half of the third thoracic segment, considerably longer than broad (fig. 5b), at the front end somewhat
more than half as broad as behind the middle; the lateral margins posteriorly somewhat convex,
anteriorly a little concave.

Antennule (figs. 5b and 5d) nearly as long as the carapace, moderately strong. First joint
slightly longer than the two next joints combined, somewhat more than twice as long as deep, some-
what produced above and before the middle considerably deeper than towards the end. Second joint
extremely produced above, increasing in depth from the base to the end of the lower margin and its
upper margin is nearly two-thirds as long as that of the first joint. Third joint considerably tapering,
- with the lower margin about twice as long as the upper; fourth joint slenderly conical, a little longer
than the lower margin of third joint, considerably shorter than its terminal sete. — Antenne short,
even a little shorter than the two proximal antennular joints combined; fourth and fifth joints com-
pletely fused.

Chelipeds (fig. 5g) somewhat robust. The basal joint even a little longer than the carpus,
with the posterior protuberance large, as long as deep and its rounded hind margin reaching behind
the anterior lower end of second thoracic segment. Carpus nearly ovate, slightly more than half as
long again as deep. Chela a little longer than the carpus, about twice as long as broad, with the
major part of its posterior margin straight and furnished with two long sete; movable finger almost
as long as the anterior margin of the hand and towards the base much narrower than the fixed finger.

Lateral margins of the thoracic segments (fig. 5a) not angular but evenly and moderately
convex. Second segment somewhat shorter than the third which is slightly shorter than the fifth or
the sixth. — Thoracic legs short. The two anterior pairs uncommonly thick (fig. 5g); third joint with
a very long, spiniform seta from the posterior angle; fourth and fifth joints very thick; subequal in,
length and with the terminal spines long or rather long; sixth joint considerably longer than the
fifth and slightly longer than seventh with claw. Three posterior pairs somewhat slender (fig. 5e)
with their spines well developed; fifth joint even longer than the sixth and slightly longer than
seventh without claw.

Abdomen a little shorter than the two preceding segments combined. Five anterior segments
(fig. 5f) with the ventral margin moderately convex; pleopods wanting. Sixth segment (fig. 5c) scarcely
as long as the two preceding segments combined, transverse, with the hind margin long and a little
concave. — Uropods, inserted on the postero-lateral angles which are cut off obliquely, are only a
little shorter than the five posterior segments combined and somewhat robust; the peduncle as long
as the sixth segment, seen from the side (fig. 5f) curved a-little downwards, with the lower margin
concave; endopod curved downwards as the peduncle, almost thicker a little from the end than near
the base, two-jointed, with the second joint more than twice as long as the first; exopod slender, as
long as the first joint of the endopod, one-jointed.

Length of a female without marsupium 2™”.

Subadult Male. Similar to the female in most features, but differing in some particulars.
— The antennule (fig. 5g), especially their two proximal joints, somewhat thicker than in the female.
— Three posterior pairs of legs (fig. 5h) have the seventh joint and the claw considerably longer

than in the female, subequal in length and together twice as long as sixth joint. — Abdomen (fig. 5 i)
The Ingolf-Expedition. III. 3. 14

106 CRUSTACEA MALACOSTRACA. II.

a little longer than the two preceding segments combined; pleopods well developed, biramous, with
the exopod much longer than the peduncle and its terminal setee about as long as the pleopod. —
Length 2.1™™.

Remarks. This small and very slender: species is easily distinguished from all other forms
by its very long and peculiarly shaped uropods.

Occurrence. It has been taken by the “Ingolf” at the two deepest stations.

South-West of Cape Farewell: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 187c fm., temp. 1.3°; 3 spec.

_ -_ = — St. 22: Lat. 58°10’ N., Long. 48°25’ W., 1845 {m., temp. 1.4°; 1 spec.

Cryptocope G. 0. Sars.

This genus was established in 1880 on two species, C. abbreviata G.O.Sars and C. Voringi G.
O. Sars. C.abbreviata must be considered the type, at it was described several years before the other
species and by Sars placed before C. Voringiz, when he established the genus. Later I established
C. arctica which is related to C. abbreviata. Norman & Stebbing established Strongylura arctophylax,
which is nearly related to C.Voringit and must be transferred to Cryptocofe. This genus is closely
related to Leptognathia, the only important difference between the two genera being the existence of
four pairs of marsupial lamelle in Leftognathia and only a single pair in Cryftocope. But females
with marsupium are known only of C. abéreviata and C. arctica, while they are unknown not only of
C.arctophylax but of C.Voringit, as far as I may infer from Sars’ detailed description of this species.
But the genus may be divided into two groups, the first comprising C. abdreviata and C. arctica,
which are small and very thick species and besides closely ‘allied, the second group comprising C.
Voringit and C.arctophylax, both large, less robust and closely allied but differing much in the relative
length of the thoracic segments and in general aspect from the two other species. As the marsupium
is unknown in these two large species it may be somewhat uncertain whether they have only a single
pair of marsupial lamelle, and if in the future that should prove not to be the case, these two species
must be removed from Cryftocope and a new genus be formed for them. But at least provisionally

they may be referred to Cryftocope.

68. Cryptocope arctica H. J. Hansen.
(Pl. XI, figs. 1a—rh.)

! 1886. Cryptocope arctica H. J. Hansen, Dijmphna-Togtets zool.-bot. Udbytte p. 209, Tab. XXI, fig. 4.

1887. _ _ _ Vidensk. Medd. naturhist. Forening i Kjobenhavn for 1887,
p. 180, Tab. VII, Fig. 1—1¢.

Female. Extremely thick (fig. 1a), from four to four and a half times as long as broad. —

Carapace extremely large (fig. ra), only a little shorter than the four following segments combined,

somewhat longer than broad, at the front end scarcely half as broad as somewhat behind the middle,

with the lateral margins somewhat convex.

CRUSTACEA MALACOSTRACA, II. 107

Antennulze somewhat long in proportion to the animal (fig. 1a), being somewhat more than
half as long as the carapace and rather slender (fig. 1b). First joint somewhat shorter than the other
joints combined, slightly more than twice as long as deep and a little more than twice as long as the
second which is not produced above; third joint a little longer than deep, rectangular and consider-
ably shorter than the second; fourth joint uncommonly long, as long as second and third joints com-
bined, slender; longest terminal seta nearly as long as the three distal joints combined. — Antenne
with fourth and fifth joints completely fused without any vestige of an articulation, about twice as
long as the penultimate joint.

Chelipeds (figs. rb and 1c) somewhat large and moderately strong. Basal joint posteriorly
produced into a considerable free portion bent much upwards and reaching distinctly behind the cara-
pace. Carpus somewhat less than twice as long as deep, nearly oblong-ovate, with the lower margin
considerably convex. Chela somewhat longer than the carpus, long and somewhat slender, being a
little less than three. times as long as broad, with two long sete near the middle of the concave
posterior margin and. with the hand distinctly narrower at the base of the movable finger than near
the middle; movable finger considerably or rather much shorter than the anterior margin of the hand,
only a little narrower than the fixed finger (fig. 1c), the incisive margin of which is somewhat sinuate,
showing two flatly vaulted and badly defined protuberances.

Thoracic segments (fig. ra) with their lateral margins very convex, producing deep incisions
between the segments; some of them are subangular. Second to fourth segment short, increasing in
length backwards, together about as long as the sum of the fifth and the sixth; second segment de-
creases considerably in breadth from near the front to the posterior end; third segment is broadest
somewhat before, and fourth a little before, the middle, while the three posterior segments are broadest
behind their middle. Fifth segment is almost broader than the second and somewhat broader than
the fourth or the seventh. — Thoracic legs (figs. 1b and 1d) long and slender; the anterior pair have
the joints from the fourth to the sixth somewhat increasing in length, and the sixth joint, which is
slender and long, is a little longer than seventh with claw. Posterior pairs (fig. 1d) have the spines
of moderate length; sixth joint is very long and considerably or much longer than seventh with claw.

Abdomen somewhat longer than the two preceding segments combined (fig. ra), seen from
above tapering considerably backwards to the posterior margin which has a very obtuse angle; four
posterior segments each with a pair of sublateral sete (figs. 1a and re). Ventral side of the five
anterior segments (figs. re and 1f) strongly serrate, as each segment bears a high, subtriangular or
subquadrangular protuberance. Pleopods generally small and their rami terminating in some moder-
ately long sete (fig. re); in the largest specimens from the “Ingolf’ Stat. 25 the pleopods are very
small (fig. rf) and their sete nearly rudimentary. Sixth segment longer than the two preceding seg-
ments combined. -- Uropods small; peduncle short and much deeper than long, thick; the endopod
with its two joints equal in length; exopod more than half as long as the endopod, more or less di-
stinctly two-jointed, with the joints subequal in length.

Length of females with marsupium 1.67—2™".

Subadult Male. Conspicuously more slender and distinctly smaller than adult females. —

Antennule (fig. 1g) considerably thicker than in the female; first joint somewhat less than twice as
t4*

ro08 CRUSTACEA MALACOSTRACA. II.

long as deep. — Five anterior abdominal segments (fig. 1h) proportionately longer than in the females,
with the pleopods somewhat long, well developed.

Remarks. C.arctica is allied and rather similar to C. abdreviata G. O. S., but according to
Sars’ text and figures and my examination of a Norwegian specimen given by him C. abdreviata is
smaller than C. arctica, its pleopods have no sete on the end of their rami, the exopod of the uropods
is one-jointed and, what is of special importance, the chelipeds are rather different, having the carpus
only one-third as long again as deep and the chela distinctly broader, two and a half times as long
as broad, with a single sete on the posterior margin.

In vain I have looked for differences of possibly specific value between the specimens from
my very different localities; my type from the Kara Sea agrees completely with the specimens from
East Greenland and from the “Ingolf’ Stations. — Some among the specimens from the “Ingolf”
Stat. 25 are larger than the others and, as already stated, have the pleopods less developed than all
other specimens seen, but no other difference could be discovered.

Occurrence. It has been taken by the “Ingolf” at nine stations.

Davis Strait: St. 32: Lat. 66°35’ N., Long. 56°38’ W., 318 fm., temp. 3.9°; 11 spec.

-—- = St. 25: Lat. 63°30'N., Long. 54°25’ W., 582 fm., temp. 3.3°; 29 spec.

-- — St. 24: Lat. 63°06'N., Long. 56°00’ W., 1199 fm., temp. 2.4°; I spec.

— — St. 36: Lat. 61°50’ N., Long. 56°21’ W., 1435 fm., temp. 1.5°; 7 spec.
Denmark Strait: St. go: Lat. 64°45’ N., Long. 29°06’ W., 568 fm., temp. 4.4°; 4 spec.
South-West of Iceland: St. 81: Lat. 61°44' N., Long. 27°00' W., 485 fm., temp. 61°; 1 spec.

— St. 78: Lat. 60°37'N., Long. 27°52’ W., 799 fm., temp. 4.5°; 27 spec.

East of North-Iceland: St. ror: Lat. 66°23' N., Long. 12°05’ W., 537 fm., temp. + 0.7°; I spec.

North of East-Iceland: St. 126: Lat. 67°19’ N., Long. 15°52’ W., 293 fm., temp. + 0.5°; 4 spec.

Furthermore this species has been taken at a number of arctic localities on both sides of Green-
land, especially East-Greenland, and off Jan Mayen by various Expeditions.

Baffin Bay: Lat. 72°20' N., Long. 59°39’ W., 170 fm., clay with stones; 1 spec. “Ingegerd

och Gladan” 1871. (H. J. Hansen).

East Greenland: Henry Land: Lat. 69°34’ N., Long. 23°35’ W., 20 fm.; 17 spec. II¢ Amdrup Exp.

_ — Hurry Inlet: Lat. 70°36'N., Long. 22°31’ W., 50 fm.; 2spec. - _ _

— _ io fm.; Ispec. - _ —

_— — Forsblad Fjord: Lat. 72°27’ N., Long. 25°28’ W., go—4o fm.; 1 spec.

II¢ Amdrup Exp.

“= oa Stormbugt, ca. Lat. 77°N., 15—20 fm.; 1 spec. Danmark Exped. (Steffensen).

Jan Mayen: 50—60 fm.; 1 spec. IIi¢ Amdrup Exped.

Distribution. The type of C.arctica was taken in the Kara Sea, 64 fm. (H.J.H.). Later
Stebbing has mentioned specimens from Novaia Zemlia or Spitzbergen, 100 fm. Recently it has been
mentioned by Sars from the Gaase Fjord, Ellesmere Land (at ab. Lat. 78° N., on the western side of
Smith Sound), 60m. (24 Fram Exped).

The geographical and bathymetrical distribution of this species. is very interesting. In the
Kara Sea, at East Greenland, Jan Mayen and in Smith Sound it has been taken in depths between

CRUSTACEA MALACOSTRACA. II. 109

ro and 9o fathoms; in the cold area it was taken by the “Ingolf” at two stations, 293 and 537 fm.; in
the warm area by the “Ingolf” at seven stations at depths varying from 318 to 1435 fathoms.

69. Cryptocope Voringii G. O. Sars.
(Pl. X, figs. 6a—6d.)

1877. Tanais Voringt G. O. Sars, Arch. for Math. og Naturv. B. II, p. 347.
1881. Cryptocope Voringii _ Arch. for Math. og Naturv. B. VII, p. 50.
. | 1885. —_ — — Den norske Nordhavs-Exp., Crust. I, p. 74, Pl. VII, figs. 5—16.

Female (without marsupium). G. O. Sars has published a very detailed description with
several figures of this sex, but a number of observations may be added.

Body, carapace, thoracic segments and abdomen, seen from above, as to all particulars nearly
as in C.arctophylax Norm. & Stebb. (comp. description and fig. 2a on Pl. XI of this species).

Antennule (fig.6a) somewhat shorter than the carapace, moderately slender. First joint con-
siderably shorter than the three other joints combined, about two and half times as long as deep and
feebly tapering; second joint distinctly less than half as long as the first and considerably produced
above; third joint somewhat shorter than the second, almost quadrangular; fourth joint long, nearly as
long as third and second joints combined. — Antenne: somewhat long; fourth and fifth joints com-
pletely fused.

Chelipeds robust (fig.6a). A coxal joint is well marked off, large, somewhat triangular and
well chitinised on the outer side. Basal joint posteriorly produced into a moderately long, free, moder-
ately thick protuberance directed backwards and upwards, and the hind margin of this protuberance
is situated beneath the front margin of second thoracic segment. Carpus only somewhat longer than
deep, being somewhat expanded downwards and showing a somewhat protruding triangle below at
the front lower angle of the ischium. Chela almost half as long again as the carpus, robust, only a
little more than twice as long as broad; movable finger somewhat shorter than the anterior margin
of the hand, robust, with a conspicuous, subtriangular and moderately low tubercle at the middle of
the incisive margin (fig.6b); fixed finger somewhat thicker than the movable, with three sete on its
posterior margin, while its incisive margin has a large, broad and somewhat high, rounded tubercle
beyond the middle and before the middle a low and badly defined protuberance; both fingers with
their end obtuse. 4

Thoracic legs rather long and slender, with their spines short or moderately short. Anterior
pairs (fig.6c) with the joints increasing much in length from the fourth to the sixth; sixth joint very
long and slightly longer than seventh with claw. Posterior pairs as in the next species (vid. infra).

Abdomen (fig.6d) somewhat shorter than the three preceding segments combined. Five anterior
segments with their ventral surface peculiarly armed; first segment with the ventral process somewhat
short, obliquely and obtusely triangular; process of second segment long, longer than broad, obliquely
triangular, somewhat curved and directed much backwards; the processes decrease much in length
from second to fourth segment, while the process on fifth segment is only a moderately low, rounded

tubercle. Pleopods very small, biramous, without sete. (In juvenile specimens with the seventh pair

IIo CRUSTACEA MALACOSTRACA, II.

of thoracic legs not developed the pleopods and the ventral processes are not found). Sixth segment
about as long as fifth, fourth and half of the third segment combined. — Uropods (fig. 6d) small and
robust; both rami distinctly two-jointed (also in juvenile specimens) and the exopod somewhat shorter
and much thinner than the endopod.

Length of the single larger specimen 4™™.; Sars stated that the female is 5.5 ™™. long.

Remarks. The differences between the females of C.Voringii and C.arctophylax are pointed
out in the “Remarks” on the latter species. Sars stated that the uropods of the female have the exopod
one-jointed, but this is decidedly incorrect; his figure of the chela is not good, and he has described
and figured (figs.5 and 6) the terminal part of the thoracic legs, viz. seventh joint with claw, quite
erroneously.

Occurrence. Taken by the “Ingolf” at three stations in the cold area.

North-West of the Feeroes: St.138: Lat.63°26'N., Long.7° 56’ W., 471 fm., temp. + 0.6°; 1 large spec.

South of Jan Mayen: St.117: Lat.69°13' N., Long. 8° 23' W., 1003 fm., temp. + 1.0°; 1juven. spec.

— - — St.116: Lat.70°05'N., Long.8° 26’ W., 371 fm., temp. + 0.4°; 1juven. spec.

Distribution: The specimens seen by Sars had been taken at three places in the cold area

West of Norway, from Lat. 63°10’ to Lat.67°56’N., and in depths ranging from 350 to 778 fathoms;

temperatures at the bottom from + 1.0° to + 1.4°.

70. Cryptocope arctophylax Norm. & Stebb.
(Pl. XI, figs. 2a—2k).

1886. Strongylura arctophylax Norman & Stebbing, Transact. Zool. Soc. London, Vol. VII, Pt. IV, p. 116,
Pl. XXIV, fig. 3.

Young Female and subadult Male. Body of the subadult male (fig. 2a) robust, slightly
more than five times as long as broad and the anterior half conspicuously broader than the posterior;
the young female is about five and a half times as long as broad. — Carapace nearly as long as the
two following segments combined, as long as or slightly longer than broad, anteriorly somewhat less
than half as broad as behind the middle, where the lateral margins are very convex.

Antennulz in the subadult male (fig. 2a) a little, in the young female somewhat, shorter than
the carapace. In the female (fig. 2e) the antennulze are somewhat slender; first joint considerably
shorter than the three following joints combined, somewhat less than three times as long as deep and
feebly tapering; second joint somewhat produced above, not fully half as long as the first, but much
longer than the third which is a little shorter above than below; fourth joint almost as long as third
and second joints combined and a little longer than the terminal sete. In the subadult male the
antennulz (fig. 2b) are much thicker; first joint slightly more than half as long again as deep; second
joint as deep as the length of its upper margin, which is half as long as the first joint; third joint
more than half as deep again as the length of its upper margin; fourth joint uncommonly long,
conspicuously longer than the two preceding joints combined, with the proximal portion somewhat
thickened, and the terminal sete are considerably shorter than the joint. Antenne: somewhat long, in
the young female (fig.2e) with, in the subadult male without, a vestige of an articulation between
fourth and fifth joints.

CRUSTACEA MALACOSTRACA. IL. III

Chelipeds robust and on the whole agreeing with those in C. Vorimgii excepting in the armature
of the fixed finger (fig.2c), which has the distal large tubercle furnished with two incisions dividing
its margin into three rounded teeth, and the proximal protuberance is higher and better defined than
in C.Voringii; in my specimens both fingers have their ends acute, while they are obtuse in my
female of C. Voringit.

Thoracic segments (fig. 2a) decrease distinctly in breadth from second to sixth. Second seg-
ment is slightly shorter than the third which is as long as the fourth and only slightly shorter
than the fifth. Second to fourth segments increase conspicuously in breadth from their posterior
. to the anterior, rather broadly rounded angle, while fifth and sixth segments are subrectangular
with their angles rounded and the lateral margins feebly protuberant behind the middle; seventh seg-
ment broader behind than in front. — The thoracic legs as in C. Vorimgii; fig.2d shows that in the
posterior pairs sixth joint is considerably longer and thinner than the fifth and distinctly longer than
seventh with claw; fig.2f shows that the upper terminal spine on sixth joint is strong and adorned
with some five pairs of lateral, oblique branches (a somewhat similar spine is found in C. Voringit).

Abdomen in the subadult male (fig.2a) as long as the three preceding segments combined; its
anterior half is as broad as seventh thoracic segment, but from the fourth segment the abdomen
tapers conspicuously; in the young female the last thoracic segment has not arrived at full size and
the abdomen is somewhat narrower than sixth segment, slightly longer than fifth and sixth segments
combined and not tapering, as the sixth segment is fully as broad as the first. In the male (fig. 2d)
the armature of the ventral side is strongly developed; the process from third segment is very long,
acute, subiriangular, with the anterior margin a little convex and the posterior margin somewhat
concave, directed mainly downwards; the process from second segment is much shorter than the third
though still large, triangular and as long as broad; the first segment has only a somewhat low,
triangular tubercle, fourth segment a somewhat higher tubercle, and on the fifth segment the protub-
erance is rudimentary. In the young female the processes (fig. 2g) or tubercles are conspicuously less
developed, but show nearly the same relative proportions as to length. Pleopods completely wanting
in the female, while in the subadult male they are well developed (fig. 2d), somewhat long, biramous,
with moderately long sete. — Uropods (figs. 2d and 2g) distinctly more slender and longer than in
C.Voringu; peduncle at least as deep as long; endopod with the two joints subequal in length;
exopod two-jointed, somewhat shorter and considerably thinner than the endopod.

Length of the subadult male 3.8™,, of the young female 3.3™™, (The female specimen described
by Norman & Stebbing was 4™". long).

Adult Male (figs. 2h—2k). On the whole somewhat reminding of males of the genus
Leptognathta. — Antennule (fig.2h) as long as the carapace and second thoracic segment combined,
seven-jointed. First joint twice as long as deep; second joint thick and slightly more than half as
long as the first; third and fourth joints very short and fifth joint short, all three somewhat cup-
shaped and fourth and fifth joints each with a close row of extremely long sensory hairs; sixth joint
about as long as the four preceding joints combined, at the end with a row of very long sensory
hairs; seventh joint long, nearly as long as the first and much thinner than the sixth, slightly longer

than the terminal sete.

II2 CRUSTACEA MALACOSTRACA. Il.

Chelipeds (fig.2h) moderately strong, somewhat long. The coxal joint is distinctly marked
off; the basal joint is very thick, only a little shorter than the carpus, which is a little less than
twice as long as deep. Chela considerably longer than the carpus, inconsiderably more than twice as
long as broad (fig. 2i); movable finger almost as long as the anterior margin of the hand and distally
much curved, and the major middle portion of its incisive margin is irregular with several moder-
ately small or very small teeth and two minute spines; the fixed finger has nearly the proximal half
of its incisive margin finely serrate, while the distal half has the two protuberances found in the
immature male, but both are lower and the distal protuberance without marginal incisions and teeth
excepting a single small, acute tooth at its end and just at the origin of the terminal, oblong-triang-
ular, acute part of the finger.

Thoracic legs long and slender (fig. 2h), subsimilar in all particulars excepting that the spines
on the anterior pairs are very short, on the posterior pairs somewhat more developed; sixth joint is
very long and considerably longer than seventh with claw.

Abdomen (fig.2k) somewhat longer and, as usually, conspicuously thicker than the thoracic
segments. Five anterior segments with ventral tubercles; the tubercle on third segment triangular
but almost twice as broad as high; from that segment the protuberances decrease in size both forwards
and backwards and all are somewhat or fully rounded. Pleopods strong with very long sete. — Sixth
segment strongly produced backwards in a somewhat slender process with the upper margin distinctly
concave; the result is that the uropods originate considerably before the middle of the segment and
terminate before its end. — Uropods (fig. 2k) with the peduncle about as long as deep; endopod three-
jointed, with first joint thicker and much shorter than the second, which is a little shorter than the
third; exopod very slender and as long as the sum of two proximal joints of the endopod, two-joiuted,
the first joint very short, the second long.

Length 3.8™™.

Remarks. C.arctophylax is allied to C. Voringiz, but the female and the subadult male of the
two species differ sharply in the ventral abdominal processes, the third process being much longer
than the others in C. arctophylax, while in C. Voringit the second process is the longest; furthermore
the female of C.Vorimgizi has small pleopods without sete, while in the female C. arctophylax pleopods
seem to be wanting; a third character-is the difference in the above-described distal tubercle on the
incisive margin of the fixed finger of the chele. — According to the figures of the male of C. Voringii
published by Sars this animal seems to differ sharply from the male of C.arctophylax by having the
first joint of both endopod and exopod of the uropods much longer in proportion to the second joint than
in the last-named species, and in C. Voringii the terminal joint of the antennulz is only somewhat longer
than sixth joint, while in C.arctophylax the seventh joint is more than twice as long as the sixth.

C.arctophylax was established by Norman & Stebbing on a single female specimen; they
referred, however, the species wrongly to the genus Strongylura, but it must be emphasized that their
work was written before any figure of Cryptocope Voringit G.O.S. or Strongylura cylindrata G.O.S.
had been published. Stebbing’s figures of the animal from above, of the cheliped, thoracic legs, etc.,
leave no doubt that the animal is either C.Voringi or C.arctophylax as defined here; the locality for

the specimen and the ventral abdominal process shown on his fig. III Pl. but not mentioned in the

CRUSTACEA MALACOSTRACA. II. 113

text shows that the animal cannot be C.Vorzmgit. One small error may be noted, viz. that the English
authors stated the exopod of the uropods to be unjointed, while it certainly is two-jointed.
Occurrence. C.arctophylax has been taken by the “Ingolf” at two deep-water stations in
the warm area.
Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 1 subadult male, 1 young
female and 1 juvenile specimen.
— — St 36: Lat. 61°50’ N., Long. 56°21' W., 1435 fm., temp. 1.5°; 1 adult male and 1 mut-
ilated juvenile specimen.
Distribution. The only specimen mentioned in the literature is the type, which has been
dredged by the “Porcupine” at Lat. 56°24’ N., Long. 11°49’ W., “midway between Ireland and Rockall”,
1380 fathoms. — C.arctophylax has only been found in the warm area, while C.Vorzmgzi is confined

to the cold area.

Tanaella Norm. & Stebb. |

This genus was established on a single specimen of a new species, 7: ungutcillata Norm. &
Stebb., and I possess a specimen of this species and a. specimen of a hitherto unknown form; all three
specimens hitherto known are females without marsupium. The genus is related to Leptognathia
but differs in some particulars. A brief description of the genus may be given here.

Body somewhat robust. The antennule have the second joint longer than third and fourth
joints combined, and the third joint is very short. Chelipeds unusually robust. Anterior pairs of
thoracic legs have the rather long sixth joint longer than the seventh with claw; while on the post-
erior pairs sixth joint is considerably shorter than seventh with claw. Five anterior abdominal seg-
ments very short and peculiarly shaped so that they, seen from the side, are somewhat angularly
bent at the median lateral line; sixth segment long, at least as long as the four preceding segments
combined. Pleopods either small without sete or wanting. Uropods robust, with a styliform, unjointed
endopod and no exopod. (Mouth-parts, marsupium and male unknown).

Remarks. TZanaella is related to Strongylura in having the sixth abdominal segment very
long in proportion to the five anterior segments, but the whole abdomen in Zamnqaella is shorter in
proportion to the thorax than in Strongylura. In the diagnosis of Zanaella Norman & Stebbing
stated that no pleopods are found, but this feature cannot be maintained as a generic character,
because my new species 7: ochracea is closely allied to 7: unguzcillata excepting in the single feature,
that it possesses small pleopods. The structure of the uropods seems to be a good character; besides the

antennule and the elongate terminal part of the posterior pairs of legs seem to afford generic characters.

71. Tanaella ochracea n. sp.
(Pl. XI, figs. 3a—3f.)
Female (without marsupium). Moderately robust (fig. 3a), a little more than six times as long

as broad, subcylindrical, tapering slightly in breadth from the carapace to sixth abdominal segment,

which is conspicuously broader than the preceding abdominal segments. — Carapace somewhat longer
The Ingolf-Expedition. III. 3. 5

I14 CRUSTACEA MALACOSTRACA. II.

than the two following segments combined, somewhat longer than broad, at the front end half as
broad as a little behind the middle; the lateral margins considerably convex; the frontal process tri-
angular, broad and of moderate length.

Antennule (fig. 3b) a little shorter than the carapace, somewhat robust. First joint slightly
longer than the three other joints combined, more than two and a half times as long as deep and
with the proximal third rather expanded below. Second joint moderately produced above, conspicuously
more than half as long as the first and somewhat longer than third and fourth joints combined, in-
creasing distinctly in depth from the base to the end; third joint very short and fourth joint uncom-
monly short and somewhat robust; terminal setee somewhat or considerably longer than fourth joint.
— Antenne long; fourth and fifth joints completely fused and conspicuously more than twice as long
as the penultimate joint.

Chelipeds robust (fig. 3b). Basal joint long, even distinctly longer than the carpus; the posterior
protuberance is very deep and its free, rounded hind margin reaches the front lower angle of second
thoracic segment. Carpus ovate, scarcely half as long again as deep, ovate. Chela considerably longer
than the carpus, twice as long as broad; movable finger much shorter than the anterior margin of
the hand, strong, with a broad, very low, very flatly triangular protuberance on the incisive margin
somewhat from its base (fig. 3c) and a minute, sharp denticle at the distal end of that protuberance;
fixed finger very broad, with two strong sete on the posterior margin, while the incisive margin has
at the base a somewhat deep and moderately narrow, not crenulated incision producing a small hole
between the fingers when the chela is closed; beyond that incision the margin is somewhat undulate
to rather near the end where it has a sharp tooth and beyond this a conspicuous incision; the terminal
part of the finger is an oblong and somewhat curved triangle with the end acute.

Thoracic segments (fig. 3a) increase gradually in length from the second to the fifth; the lateral
margins of each segment are nearly straight excepting at both ends, but the margins of seventh seg-
ment are somewhat convex. — Thoracic legs somewhat short. The two anterior pairs (fig. 3b) moder-
ately slender, fourth joint with a rather long spine on the posterior angle; fifth joint a little longer
than the fourth, with the anterior distal spine long and the posterior spine much shorter; sixth joint
with fine denticles along the posterior margin and on the end (fig. 3d), considerably longer than the
fifth and a little longer than seventh with the straight claw. Three posterior pairs moderately strong,
with somewhat long spines on the fourth and especially on fifth and sixth joints (fig. 3e); sixth joint
somewhat longer than the fifth but much shorter than the seventh with claw, the seventh joint being
long but yet shorter than the very long claw, and both are finely ciliated below.

Abdomen somewhat shorter than the three preceding segments combined (fig. 3a). Five anterior
segments short, scarcely as broad as the posterior thoracic segments, seen from the side (fig. 3f) a
little angularly bent at the lateral margin; the ventral side with somewhat low, rounded protuberances.
Pleopods very small, biramous, without sete. Sixth segment even perceptibly longer than the sum
of the four preceding segments, seen from above (fig. 3a) broader than these segments and with the
posterior margin and the lateral margins together evenly curved like the greater part of a circle. —
Uropods a little shorter than sixth segment (fig. 3f); peduncle somewhat longer than deep; endopod

about twice as long as the peduncle, styliform.

CRUSTACEA MALACOSTRACA. IL II5

The body is shining and its anterior half deeply reddish yellow.

Length of the single specimen 3.0™™.

Occurrence. It has been taken at the deepest “Ingolf” station.

South-West of Cape Farewell: St. 38: Lat. 59°12’ N., Long. 51°05’ W., 1870fm., temp. 1.3°; 1 spec.

Remarks. Tochracea differs from 7: unguicillata Norm. & Stebb. especially in the shape of
the incisive margins of the chelez, the shape of the five anterior abdominal segments when seen from

the side, the shape of the last segment from above and by possessing small pleopods.

72. Tanaella unguicillata Norm. & Stebb.
(Pl. XI, figs. 4a—4d.)

1886. TZanaella unguicillata Norman & Stebbing, Tranact. Zool. Soc. London, Vol. XII, Pt. IV, p. 118,
Pl. XXIV, fig. IV.

Female (without marsupium). The single specimen is so strongly curved that it was im-
possible to straighten it without breaking. But it seems to differ slightly from 7. ochracea as to the
general shape of the body, outline and relative length of the carapace and thoracic segments (comp.
fig. IV D in the English paper quoted.)

Antennulz (fig. 4a) somewhat shorter than the carapace, but otherwise almost as in 7: ochracea,
the most important difference being, that the second joint is proportionately a little longer and
cylindrical, considerably more than half as long as the first joint and a good deal longer than the
two distal joints together. — Antennz with a feeble articulation between fourth and fifth joints, which
are more than three times as long as the penultimate joint.

Chelipeds very robust (figs. 4a and 4b). The basal joint not fully as long as the carpus, very
deep, with the hind margin of the deep posterior protuberance very flatly convex. Carpus not quite
half as long again as deep. Chela somewhat longer than the carpus, distinctly less than twice as
long as broad; movable finger much shorter than the anterior margin of the hand, with a somewhat
high, triangular protuberance on the incisive margin somewhat from its base and a minute, sharp
denticle just beyond that protuberance (fig. 4b); fixed finger very broad, with two strong sete on its
posterior margin, while its incisive margin has at the base a somewhat deep and long incision cren-
ulated with some five or six obtuse saw-teeth, producing a small hole between the fingers when ad-
duced, and beyond that incision the margin is somewhat undulate to rather near the end, where a
very obtuse angle and beyond this a triangular incision are seen; the ends of both fingers are obtuse.

Three anterior pairs of thoracic legs (fig. 4a) proportionately more slender than in T. ochracea
and decreasing conspicuously in length from second to fourth pair; fourth and fifth joints subequal in
length and with the length of their spines as in 7: ochracea; sixth joint much longer than the fifth
or the seventh with its straight claw. Three posterior pairs (fig. 4c) nearly as in T. ochracea; seventh
joint with its long claw much longer than the sixth joint, finely ciliated and nearly straight or curved
distinctly upwards.

Abdomen only a little shorter than the three preceding segments combined, seen from the side

(fig. 4d) uncommonly thick and thickest a little before the middle. Five anterior segments short, seen
15°

116 CRUSTACEA MALACOSTRACA | II.

from the side with their vertical margins most curiously bent twice at the lateral margin. Pleopods
wanting. Sixth segment even a little longer than the four preceding segments combined; its posterior
margin is not broadly rounded as in T. ochracea but a little produced behind with a somewhat obtuse
angle. — Uropods much shorter than the sixth segment, thus somewhat shorter than in 7: ochracea,
with the endopod not quite twice as long as the peduncle, but otherwise nearly as in the last-
named species.

The animal is somewhat light greyish.

Length of the single specimen about 3.2™™, thus a little larger than that of the English authors.

Remarks. The specimen described belongs unquestionably to T. wnwgwicillata; especially the
shape of the proximal parts of both fingers of the chele and the lateral view of the abdomen as com-
pared with Stebbing’s figures proves that beyond doubt. The main differences between 7: ochracea
and 7: wnguicillata have been pointed out in the “Remarks” on the first-named species.

Occurrence. It has been taken by the “Ingolf” at the following place.

South of West-Iceland: St. 69: Lat. 62° 40’ N., Long. 22°17’ W., 589 fm., temp. 3.9°; 1 spec.

Distribution. The type of Norman & Stebbing was dredged by the “Porcupine” on the
slope of the English Channel, Lat. 49°7' N., Long. 10°57’ W., 96 fathoms. No other specimen has been

recorded in the literature.

Strongylura G. O. Sars.

This genus was established on a single species, .S. cylindrata G.O.S., of a peculiar aspect. This
form is in most characters allied to species of Leplognathia with the pleopods rudimentary or wanting,
but it differs by having the abdomen in the female and the subadult male extremely long, only some-
what shorter or even as long as the five posterior thoracic segments combined, while the sixth ab-
dominal segment is extremely long, at least a little longer than the three preceding segments combined,
and the biramous uropods are small and thick. Furthermore it differs from Leftoguathia and reminds
of Cryptocope arctica and Tanaopsis in having third and fourth thoracic segments each conspicuously
shorter than the fifth or the sixth segment, the three anterior segments together being in reality
scarcely as long as the sum of fourth and fifth segments.

The “Ingolf” material contains two species which I refer to Stvongylwra; one of them is less
characteristic than S. cylindrata, while the other species is somewhat difficult, but after long hesitation
I have referred it to S. cylindrata.

Cryptocope arctophylax, established by Norman & Stebbing as a species of Strongylura, differs
widely from this genus but is, as already stated, allied to Cryptocope Voringit G.O.S. No other species
hitherto described has been referred to Strongylura.

73. Strongylura cylindrata G. O. Sars.
(Pl. XII, figs. ra—11.)

1881. Strongylura cylindrata G.O.Sars, Archiv for Math. og Naturv., B. VII, p. 53.
! 1896. o- ~ — Account Crust. Norway, Vol. II, p. 36, Pl. XVI, fig. r.

CRUSTACEA MALACOSTRACA. II. II7

In the last-named work Sars has given a good representation of this species, viz. figures of a
female without marsupium from above and from the side, together with drawings of appendages. He
presented the Copenhagen Museum with two of his co-types, but they differ in some points and
especially in the antennule from his figures and description. A comparison between my fig. 1g, drawn
from one of his co-types, with his figures on Pl. XVI shows, that the antennule are much more slender
than figured by Sars and above all that the moderately slender terminal joint is slightly shorter than
the two preceding joints combined, while according to Sars that joint is much shorter than the sum
of the two preceding joints and very thick. Furthermore my figures of second and sixth legs (figs.
th and ri) as compared with Sars’ figures of second and seventh legs show that the thoraci¢ legs
drawn by him have the joints conspicuously shorter in proportion to thickness than in my Norwegian
specimens presented by. him. As to the relative length of thorax and abdomen, Sars’ figures agree well
with my Norwegian specimens, but in these the uropods are more remote from the end of abdomen
(fig. tk) than according to his figures, in which the uropods reach beyond the end of abdomen which
is not the case in his co-types mentioned, while it exists in all the “Ingolf? specimens. Sars stated
that he had taken .S. cylimdrata at several places “in depths ranging from 50 to 200 fathoms”.

Judging from these statements one might be tempted to suppose that Sars had mixed up two
different species. But though the “Ingolf’ material is small, it originates from three localities with
the depth from about 1200 to near 1700 fathoms, two specimens from the cold and two from the warm
area, and these specimens show various differences. Furthermore, the antennulz show features inter-
mediate between Sars’ figures of .S. cyimdrata and his two co-types mentioned; the thoracic legs are
in two “Ingolf? specimens about as drawn by Sars, in two other specimens still shorter and thicker.
For such reasons I am apt to think that all specimens seen by Sars or me are in reality variations
of the same species. But it may be of some significance to add some further notes on the “Ingolf”
specimens from each locality.

The female from Stat. 113 (fig. 1a), which measures 3.7™™ in length, is more slender than any
other of my specimens and than that figured by Sars, as it is even slightly more than nine times as
_ long as broad. But its antennule (fig. rb) have the fourth joint shorter and thicker than in the
specimens from the other stations, though less thick than in Sars’ drawing (fig. 1a"), while the chelze
are more robust and the thoracic legs (figs. rc and rd) shorter and thicker than in the specimen
figured by Sars or in my specimens from other places. The chelz (fig. 1b) are slightly more than
twice as long as broad; the abdomen is longer than in specimens from any other source, being as
long as the five posterior thoracic segments plus more than half of second segment combined, while
the sixth abdominal segment is only a little longer than the three preceding segments combined.
In Sars’ figures and in his two co-types the abdomen is scarcely as long as the five posterior thoracic
segments combined, but its sixth segment is as long as the four preceding segments together. — The
subadult male from the same place — Stat. 113 — agrees in all respects with the female and its
antennule are but slightly thicker, but it has moderately developed pleopods, the rami of which are
somewhat long in proportion to the peduncle and the sete on their terminal margin short (as
figured by Sars).

The subadult male from the “Ingolf” Stat. 24 (figs. re and 1f) agrees as to the relative length

118 CRUSTACEA MALACOSTRACA. II,

of the thorax and abdominal segments, the length and thickness of the chele and the thoracic legs
with Sars’ figures. It may be mentioned that the chelz in this “Ingolf” specimen (fig. re), in Sars’
figure and in my Norwegian specimens are conspicuously more slender than in the above-described
specimens from Stat.113, the chela being somewhat more than twice as long as broad. But in this
“Ingolf? specimen from Stat. 24 the antennule are intermediate between those from Stat. 113 and my
Norwegian specimens (fig. 1g), especially their fourth joint is slightly shorter and distinctly thicker
than in the last-named specimens. — The young male from the “Ingolf”’ Stat. 20 has the pleopods
rudimentary; the sixth abdominal segment is as long as the five other abdominal segments combined,
but as to the length and thickness of the thoracic legs, the length of abdomen in proportion to the
thorax and the shape of the chele the specimen agrees with Sars’ figures, while the antennule, and
especially their short and thick fourth joint, are similar to those in the specimens from Stat. 113.
From this somewhat detailed investigation it may be seen that it is impossible to divide my
somewhat scanty material from both the cold and the warm areas and from Norway into two or three
species and besides to take the Norwegian specimens figured and described by Sars into account,
because the characters are mingled apparently without reference to depth or temperature. Therefore
I feel myself compelled to refer all specimens to the same species which shows considerable but gradual
variation in several features.
Length of the largest specimen, the female from Stat. 113, 3.7", of my largest specimen from
Norway 3.0™™. i |
Occurrence. It has been taken by the “Ingolf” at three stations.
Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°;
1 subadult male.
South-East of Cape Farewell: St. 20: Lat. 58°20’ N., Long. 40°48’ W., 1695 fm., temp. 1.5°;
I young male.
South of Jan Mayen: St. 113: Lat. 69°31’ N., Long. 7°06’ W., 1309 fm., temp. + 1.0°;
1 female and 1 subadult male.
Distribution. S.cylimdrata was hitherto known only from several places at the southern
and western coasts of Norway, “in depths ranging from 50 to 200 fathoms. It extends northwards
to Selsovig, situated just within the polar circle.”

74. Strongylura minima un. sp.
(Pl. XI, figs. 5a—5d.)

Subadult Male. This tiny species is, seen from above (fig. 5a), moderately slender, about
seven and a half times as long as broad, subcylindrical, yet tapering slightly towards both ends. —
Carapace not quite as long as the three following segments combined, narrower than the next seg-
ment, much longer than broad, anteriorly conspicuously more than half as broad as behind the middle.

Antennule moderately robust (fig. 5b), slightly longer than the carapace. First joint two and
a half times as long as deep, somewhat shorter than the three other joints combined; second joint
somewhat produced above and half as long as the first; third joint middle-sized, distinctly longer than

CRUSTACEA MALACOSTRACA. II. I1g

deep; fourth joint somewhat shorter than the two preceding joints combined and much shorter than the
longest terminal seta. — Antenne of middle length; second and third joints uncommonly long; fourth

and fifth joints completely fused, about twice as long as the sixth joint.

Chelipeds (fig. 5b) moderately strong. Basal joint somewhat more than half as long as the
carpus, with the posterior protuberance deep but short, its hind margin free and rounded and reaching
somewhat behind the front lower angle of second thoracic segment. Carpus somewhat long, slightly
more than twice as long as deep, with the lower margin distinctly convex. Chela as long as the
carpus, slightly more than twice as long as broad, with the hind margin somewhat concave; movable
. finger somewhat short, very much shorter than the anterior margin of the hand, moderately strong;
fixed finger with a single long seta on the posterior margin at its base, and with a more proximal,

triangular protuberance and a more distal triangular tooth on the incisive margin.

Thoracic segments, seen from above (fig. 5a), as to relative length and the shape of the lateral
margins in the main similar to those in S. cylindrata. The lateral margins of the second segment are
rather convex; the three anterior segments together a little shorter than fifth and sixth segments
combined. — Thoracic legs of moderate length and thickness. The two anterior pairs (fig. 5b) have
fourth and fifth joints subequal in length and proportionately short, together as long as the sixth
joint, which is somewhat longer than seventh with claw, and on these legs the spines are very short
or partly wanting. Three posterior pairs somewhat similar to those of thick-legged specimens of
S. cylindrata.

Abdomen only as long as seventh, sixth, fifth and half of the fourth thoracic segments com-
bined; sixth segment as long as the three preceding segments together, its posterior margin is some-
what convex with an obtuse median angle (fig. 5a). Pleopods proportionately long (fig. 5c); the
exopod much longer than the peduncle and somewhat longer than the endopod; the terminal sete
longer than the rami. — Uropods not much more than half as long as sixth segment, moderately
robust (fig. 5c); peduncle short and thick, much deeper than long; endopod with the proximal joint
twice as long as the distal; exopod about half as long as and much thinner than the proximal joint
of the endopod.

Length of the single specimen 1.05™".

Female (without marsupium). As the single specimen is so curved that I did not venture
to make an attempt to straighten it, the description of the species has been based on the subadult

male, and some remarks on the female may be added.

The specimen is rather similar to the male in most respects, but differs in some minor parti-
culars. As far as can be judged the specimen is somewhat more slender in proportion to length than
the subadult male.

The carapace is-considerably shorter than the three following segments combined. — The an-
tennule (fig. 5d) are somewhat longer than the carapace, slender; the first joint is three times as
long as deep; fourth joint is distinctly shorter than the second. — Chelipeds with the carpus about
half as long again as the basal joint and nearly twice as long as deep; chela somewhat more than

twice as long as broad, with the movable finger proportionately a little longer than in the male; the

120 CRUSTACEA MALACOSTRACA., II.

two protuberances on the incisive margin of the fixed finger are well developed, and when the fingers
are closed a row of three oblong holes are seen between them.
Abdomen proportionately as long as in the male, but the sixth segment is longer, being even
slightly longer than the sum of fifth, fourth, third and half of the second abdominal segment.
Length 1.25™".
Occurrence. This species has been taken by the “Ingolf? at two deep stations in the
warm area.
Davis Strait: St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 1 female. ;
South of Iceland: St. 64: Lat. 62°06' N., Long. 19°00’ W., 1041 fm., temp. 3.1°; 1 subadult male.
Distribution. This tiny species is easily separated from S. cylindrata. It is the smallest
species hitherto known from the North Atlantic and probably smaller than any species hitherto

described.

Strongylurella n. gen.

Allied to Strongylura, but differing in the following characters.

The thoracic segments as to relative length as in Leptognathia, consequently differing from
Strongylura in having the three anterior segments combined conspicuously longer than the fifth and
sixth segments combined. The last abdominal segment shorter than in Strongylwra and longer than
in Leptognathia, being slightly longer than broad. The uropods have the endopod divided as in
Strongylura, as its proximal joint is much longer than the distal, but the exopod is wanting.

Remarks. It was found necessary to establish this new genus on a single species which

differs materially from Leptoguathia, Strongylura and allied genera.

75. Strongylurella indivisa n. sp.
(Pl. XII, figs. 2a—2e.)

Female (without marsupium). Body very slender (fig. 2a), about eight and a half times as
long as broad, broadest behind the middle of the carapace and thence tapering slightly to the base
of the abdomen. — Carapace large (fig. 2a), even a little longer than the two following segments
combined, considerably longer than broad, at the front end scarcely half as broad as behind the middle
and with the lateral margins evenly and moderately convex.

Antennule (fig. 2b) somewhat shorter than the carapace, shaped nearly as in Strongylura cy-
lindrata. First joint a little shorter than the three other joints combined, two and a half times as
long as deep, but only a little deeper before the base than at the distal end. Second joint consider-
ably produced above, a little less than half as long as the first and distally thicker than at the base;
third joint moderately large and distinctly longer than deep; fourth joint conspicuously longer than
the third and shorter than the second. — Antenne moderately short; fourth and fifth joints completely
fused, about two and a half times longer than the sixth joint.

Chelipeds moderately robust (fig. 2b). The basal joint is somewhat shorter than the carpus,

CRUSTACEA MALACOSTRACA. II. I2I

its posterior protuberance somewhat long, longer than deep, with the rounded hind margin situated
considerably before the front lower angle of second thoracic segment. Carpus a little more than half
as long again as deep, with the upper margin very convex, the free part of the lower margin feebly
convex. Chela considerably longer than the carpus, a little more than twice as long as broad, with
two strong sete on the posterior margin, which is distinctly convex between the distal of these setze
and the base; movable finger considerably shorter than the anterior margin of the hand, somewhat
robust; when the fingers are adduced a triangular, oblong hole is seen between their proximal parts,
while the subdistal part of the incisive margin of the fixed finger is rather convex.

Thoracic segments (fig. 2a) taper slightly in breadth from second to seventh segment; their
lateral margins are feebly convex or nearly straight and a little curved at both ends. Second seg-
ment a little shorter than the third which is somewhat shorter than the fifth. — Thoracic legs some-
what short. The two anterior pairs (fig. 2b) are moderately strong, with sixth joint long, somewhat
shorter than fourth and fifth joints combined and considerably longer than seventh with claw; most
of their spines short. The three posterior pairs rather slender (fig. 2c); their sixth joint about as long
as the fifth but much shorter than seventh joint with claw; seventh joint and claw subequal in length.

Abdomen’ as long as seventh, sixth, fifth and half of the fourth thoracic segment combined
(fig. 2a). Five anterior segments with the ventral line straight (fig. 2d). Pleopods wanting. Sixth
segment distinctly shorter than the three preceding segments combined (figs. 2d and 2e); its lateral
margins somewhat long and straight, while each half of the posterior margin is considerably concave,
as the median half of the segment is produced posteriorly into a triangle about twice as broad as
long and with the end acute (fig. 2d). — Uropods as long as the straight lateral margin of the last
abdominal segment, moderately strong; peduncle, seen from the side (fig. 2e), oblong rectangular;
endopod twice as long as the peduncle, with its proximal joint slightly less than twice as long as the
distal joint; exopod completely wanting.

Length of the single specimen 1.7™".

Remarks. S.imdzvisa is easily distinguished from all other species mentioned in this paper
by having a well developed and two-joirited endopod but no exopod on the uropods; furthermore the
shape of the last abdominal segment is very characteristic.

Occurrence. Taken by the “Ingolf” at the following station.

South-West of Iceland: St. 78: Lat. 60° 37’ N., Long. 27°52’ W., 799 fm., temp. 4.5°; 1 spec.

Paranarthrura n. gen.

Description. As to general aspect somewhat similar to Leptognathia. The body tapers
considerably from the posterior part of the carapace or the front part of second segment to the ab-
domen. — Antennulze four-jointed and shaped as in Leptogmathia. Antennze with fourth and fifth
joints completely fused. — Mouth-parts (examined only in P. zwsignis) somewhat aberrant; the labrum
(Pl. XII, fig. 3c) is produced in a somewhat long, distally obtuse triangle; the mandibles (figs. 3c

and 3d) are somewhat long, without molar process, curved inwards far beyond the middle, and the
The Ingolf-Expedition. HI. 3. 16

122 CRUSTACEA MALACOSTRACA. II,

incisive margin of the right mandible has few and obtuse teeth, while that of the left mandible is
somewhat incised and the movable lobe moderately developed. . The maxillule are very slender (fig. 3¢);
the maxillipeds (fig. 3f) have their proximal unpaired part long, the lobes are well separated to their
base and each has two short sete at the terminal margin.

The thoracic segments have the lateral margins conspicuously angular and the anterior seg-
ments as to length developed as in Leptognathia. The thoracic legs shaped as in the last-named genus.

Abdomen in the female very short (figs. 3a and 4a); its five anterior segments combined at
most as long as seventh thoracic segment, considerably narrower than this segment and somewhat
narrower than sixth abdominal segment, which is broader than long and posteriorly somewhat pro-
duced. Pleopods wanting. Uropods short, with the exopod either unjointed or not marked off, the
endopod one-jointed or two-jointed. — In the subadult male the five anterior abdominal segments are
somewhat longer than in the female and their pleopods are moderately long, but terminal sete are
either somewhat short (fig. 3m) or quite wanting (fig. 5c). — (Adult males unknown).

Remarks. This genus differs from all preceding genera with four-jointed antennule in having
the five anterior abdominal segments much reduced both in length and breadth; in the female of the
genus Anarthrura G.O.S. the abdomen is also much reduced in length, but all segments are fused
so that not even a vestige of a division into segments is visible. Furthermore, in Azarthrura the
coxal joint of the chelipeds is, according to Sars’ figure, developed as a free, outstanding joint different
from the structure found in any species of Paranarthrura. Finally, the abdomen in the subadult male
of Anarthrura is according to Sars much more developed than in Paranarthrura (I consider the male
of Anarthrura figured by Sars to be not adult but in all probability only subadult, because its anten-
nule contain only five joints as in subadult males of several species of Leptognathia, and because the
thoracic segments and their legs do not differ materially from those in the female.)

Three new species secured by the “Ingolf? in the warm area are referred to this new genus.

These species differ materially from each other in several particulars.

76. Paranarthrura insignis n. sp.
(Pl. XII, figs. 3a—3m.)

Female. Moderately slender (fig. 3a), almost seven times as long as the breadth of the cara-
pace somewhat before its hind margin and tapering considerably backwards. — Carapace large, as
long as the two following segments combined (fig. 3a), somewhat longer thau broad, somewhat behind
the middle more than two and a half times as broad as at the insertion of the antennule and thus
nearly pear-shaped.

Antennulz a little or somewhat shorter than the carapace, rather slender (fig. 3b). First joint
uncommonly long, somewhat longer than the three other joints combined, nearly three and a half
times as long as deep, but considerably deeper somewhat from the base than somewhat beyond the
middle. Second joint distinctly produced above, as deep as the distal part of the first joint but slightly
more than one-third as long as that joint; third joint distinctly longer than deep; fourth joint some-

what shorter than the second. — Antennz slender and moderately short.

CRUSTACEA MALACOSTRACA. IL 123

Chelipeds moderately strong (fig. 3b). Basal joint short, somewhat deeper than long, without
any posterior protuberance, as its whole posterior margin is oblique and inserted on a very large,
well defined coxal area; the hind margin of the joint is very remote from the front lower end of se-
cond thoracic segment. Carpus twice or more than twice as long as deep, peculiarly shaped; the
lower margin has a very low protuberance with two small sete at the middle and behind and beyond
this protuberance the margin is feebly concave; the upper proximal part of the joint is somewhat
produced backwards. Chela somewhat longer than the carpus and a little more than twice as long
as broad; the movable finger somewhat robust, as long as or slightly longer than the anterior margin
. of the hand, which is conspicuously but more or less irregularly arcuate; the posterior margin of the
chela is sinuate, showing three concave or flatly incised places (figs. 3b and 31 — the last figure
drawn from a subadult male); the incisive margin of the fixed finger has a sharp tooth somewhat
from the end.

Thoracic segments, seen from above (fig. 3a), peculiarly shaped and increasing somewhat in
length from the second to the sixth. Second segment, which is slightly narrower than the carapace,
is considerably broader anteriorly than behind, with the lateral margins converging considerably back-
wards. Third to seventh segment on each lateral margin with a rounded protuberance, which on the
third segment is situated somewhat before the middle, on the following segments gradually more
backwards; the front half of each lateral margin of the three posterior segments is conspicuously
convex. In specimens without marsupium (fig. 3b) each segment has on the ventral side a moderately —
long, slender, acute process; on second segment this process is situated near the front end, on the
following segments gradually more backwards, on seventh segment (fig. 3h) somewhat or a little be-
fore the middle; the anterior processes (fig.3b) are curved much forwards, while on the posterior seg-
ments they are directed more downwards (fig. 3h); in females with marsupium the processes of second
to sixth segments are lost, but the process on seventh segment is preserved. — Thoracic legs (figs. 3b
and 3g} rather slender, decreasing in length from second pair, which are somewhat long, to seventh
pair, which are somewhat short; most of the spines on the legs are somewhat long. Second pair
with fourth and fifth joints rather long, sixth joint somewhat longer than the fifth and about as long
as seventh joint with claw; the spine on the anterior angle of fifth joint long. Seventh pair (fig. 3g)
with sixth joint a little or slightly shorter than fifth joint and somewhat shorter than seventh joint
together with the fine, curved claw.

Abdomen very short. Five anterior segments, when straightened (fig. 3i), together a little or
somewhat shorter and much narrower than seventh thoracic segment. Sixth segment, seen from above
(fig. 31), a little longer than the three preceding segments combined, much broader than long and
somewhat broader than the fifth segment, posteriorly at the middle distinctly triangularly produced;
. the lateral margins very convex. — Uropods about as long as, or a little longer than, sixth segment,
robust; exopod not marked off and directed essentially downwards (fig. 3h), being an oblong, triangular
protuberance from the distal angle of the peduncle and longer than the peduncle itself, which is at
least as long as deep; endopod two-jointed, with the first joint distinctly shorter than the second.

Length of a large female without marsupium 2.9"", of females with marsupium 2.6—2.8™.

Subadult Male. It differs from full-grown females without marsupium in three features
16*

124 CRUSTACEA MALACOSTRACA. II.

The antennule (fig. 3k) are considerably thicker; the first joint somewhat or rather considerably
shorter than the three other joints combined and only a little more than two and a half times as
long as deep; second joint considerably produced above; fourth joint nearly as long as the second
and thickened, especially at the base. The five anterior abdominal segments (fig. 3m) are much longer
than in the female, together about twice as long as seventh thoracic segment. The pleopods are
somewhat large, with the rami much longer than the peduncle, but the terminal sete are slightly
more than half as long as the rami and somewhat thick.

Smaller than the females, measuring only 2.2—2.3™™.

Remarks. FP. imsignis is a fine form which is abundantly distinguished from the two following
species by possessing ventral thoracic processes, by the shape of the thoracic segments, the chelipeds
and above all by the uropods.

Occurrence. It has been taken by the “Ingolf” at three stations.

Davis Strait: St. 32: Lat. 66°35' N., Long. 56°38’ W., 318 fm., temp. 3.9°; I spec.

_ — St.25: Lat. 63°30’ N., Long. 54°25) W., 582 fm., temp. 3.3°; more than a hundred
specimens.

_ — St. 24: Lat. 63°06’ N., Long. 56°00’ W., 1199 fm., temp. 2.4°; 6 spec.

77. Paranarthrura subtilis un. sp.
(Pl. XII, figs. 4a—qd.)

Female (without marsupium). Rather slender (fig. 4a), about seven and a half times as long
as broad a little behind the front end of second thoracic segment and tapering considerably backwards.
— Carapace as long as the second and half of the third segment combined — these segments are
long —, somewhat longer than broad, not fully twice as broad at the middle as at the front end and
with the lateral margins moderately convex.

Antennulz much shorter than the carapace (fig. 4b), somewhat thick. First joint subcylindrical
and somewhat more than twice as long as deep; second joint scarcely produced above and half as
long as the first; third joint a little longer than deep; fourth joint scarcely as long as the second. —
Antennze short, a little more than half as long as the antennule.

Chelipeds (fig. 4b) somewhat slender. Basal joint short, about as long as deep, without posterior
protuberance, but attached by the whole oblique hind margin, which is situated a little behind the
middle of the cephalothorax. Carpus two and a half times as long as deep, with the upper proximal
part produced backwards, the major part of the upper margin nearly straight and the lower margin
a little sinuate. Chela scarcely as long as the carpus, somewhat slender, being two and a half times
as long as broad; the movable finger as long as the front margin of the hand, moderately robust;
the posterior margin is a little concave at the middle, where a single seta is inserted; the end of both
fingers very acute.

Thoracic segments (fig. 4a) with the lateral margins very conspicuously angular; the angles,
which on second segment are near the front end, are on the following segments placed gradually

more backwards, on seventh segment somewhat from the posterior end; the margins between the acute

CRUSTACEA MALACOSTRACA, II. 125

or somewhat rounded angles and both ends of each segment are straight. Third, fourth, fifth and
sixth segments subequal in length, while second and seventh segments are somewhat shorter. No
ventral processes are found. — Thoracic legs (figs. 4b and 4c) moderately short, and all subequal in
length and moderately slender; the relative length of the joint almost as in P. zwsignis, but the spines
on the anterior pairs are much shorter than in that species.

Abdomen very short (fig. 4a). Five anterior segments combined scarcely as long as and con-
siderably narrower than seventh thoracic segment (fig. 4d). Sixth segment about as long as the four
preceding segments combined and somewhat broader than the fifth segment; each half of its posterior
. margin is considerably concave, as the median third of the segment is produced backwards in a
triangle with the end nearly acute. — Uropods robust and somewhat shorter than the sixth segment;
the peduncle longer than deep (fig. 4c), with the outer distal angle a little produced as a small rudi-
ment of an exopod not marked off; the endopod unjointed, slightly longer than the peduncle.

Length of the largest specimen 1.9™".

Remarks. P. subtilis is easily distinguished from all other Tanaidz with four-jointed anten-
nulz described in this paper by its uropods. The antennule are unusually thick and shaped as in
subadult males of allied forms, but as no pleopods are found the specimens must be females.

_ Occurrence. Taken by the “Ingolf” at a single station.
Davis Strait: St. 32: Lat. 66°35’ N., Long. 56°38’ W., 318 fm., temp. 3.9°; 7 spec.

78. Paranarthrura clavipes n. sp.
(Pl. XII, figs. 5a—5 cc.)

Immature Male and juvenile Specimen. Body, seen from above (fig. 5a), moderately

slender, broadest across the carapace and tapering much backwards to the abdomen. — Carapace large
(fig. 5a), somewhat shorter than the two following segments combined — which are uncommonly
long —, somewhat longer than broad and broadest a little before the middle, which is nearly more

than twice as broad as the front end, and consequently the lateral margins are very convex.
Antennulee (fig. 5b) much shorter than the carapace. First joint a little longer than the three
other joints combined and in the immature male two and a half times as long as deep; second joint
somewhat produced above and not half as long as the first joint; third joint quite short; fourth joint
considerably shorter than the second. — Antennz of moderate length; the joint composed by the
fusion of fourth and fifth joints is very long, while the penultimate joint is unusually short.
Chelipeds (fig. 5b) moderately strong. The basal joint is considerably longer than deep,
posteriorly produced in a protuberance which is narrowly rounded behind, and the distance between
its end and the front lower angle of second thoracic segment is a little more than half as long as the
joint itself. Carpus slightly more than half as long again as the basal joint, somewhat more than
twice as long as deep, with the upper basal part somewhat produced backwards; most of the upper
margin and nearly the whole free lower margin are straight and slightly converging. Chela slightly
longer than the carpus, almost two and a half times as long as broad, regularly shaped with the
fingers acute; the posterior margin almost straight with a single seta; the movable finger slightly

shorter than the anterior margin of the hand.

126 CRUSTACEA MALACOSTRACA. II.

Thoracic segments, seen from above (fig. 5a), in the main as in P. subtilis, but more tapering
than in this species; the lateral margins are sharply angular; second segment is unusually long, only
a little shorter than the third, which is as long as the fourth or the fifth. — Second and third pairs
of thoracic legs (fig. 5b) somewhat long and slender, with the spines thin and moderately or very
short; fifth joint conspicuously longer than the fourth; sixth joint only a little shorter than fourth
and fifth joints combined and considerably longer than the seventh joint with claw. Three posterior
pairs (fig. 5c) only a little shorter than second pair; second joint is clavate, being very thin towards
the base while the distal part is thick; sixth joint is somewhat longer and considerably thinner than
the robust fifth joint and somewhat longer than the seventh joint with claw.

Abdomen in general shape somewhat similar to that of P.sawd/ilis. As the seventh thoracic
segment is only half developed — having no legs — in the juvenile specimen shown in fig. 5a, the
length of the abdomen must in this figure be compared not with seventh but with sixth thoracic
segment. In the immature male (fig. 5c) the five anterior segments combined are nearly half as long
again as seventh thoracic segment; the pleopods are of moderate size, with the exopod longer than
the peduncle, but both rami completely without sete. In the immature male the sixth abdominal
segment is not quite as long as the three preceding segments combined; in the juvenile specimen it
is even longer than the four preceding segments combined; it is a little less broad in proportion to
length than in P. szbtilis, and the produced part between the uropods is not triangular but rounded.
— Uropods considerably shorter than the sixth segment; the peduncle is much shorter than deep
(fig. 5c); the endopod two-jointed, with the second joint much longer than the first; the exopod is
well marked off, one-jointed, a little more than half as long as, and much thinner than, the endopod.

Length of the immature male 2.15™", of the juvenile specimen 1.7™".

Remarks. In the structure of the uropods and the posterior protuberance on the basal joint
of the chelipeds P. clavipes is sharply distinguished from the two preceding species. The clavate shape
of the second joint of the three posterior pairs of thoracic legs is also very characteristic.

Occurrence. ‘Taken by the “Ingolf” at the deepest of its stations.

South of the Davis Strait: St. 38: Lat. 59°12’ N., Long. 51° 05’ W., 1870 fm., temp. 1.3°; 2 spec.

(1 immature male and 1 juvenile specimen).

CRUSTACEA MALACOSTRACA. II. 127

. 4a.

EXPLANATION OF THE PLATES.

Plate I.
Fig. 1. Apseudes vicinus n. sp.
Body of the single specimen, an immature female, from above; >< 21.
Left cheliped, from the outer side; < 32.
Left second thoracic leg, from the outer side; < 32.

Fig. 2. <Apseudes lenurs un. sp.
Cephalothorax and four thoracic segments of a subadult female from the “Ingolf” Stat. 24,
from above; < 13.
Seventh thoracic segment and abdomen of the same specimen, from above; x 13.
Left cheliped of a subadult female, from the outer side; x 24. .
Left second thoracic leg of the same specimen, from the outer side; x 24.

Left seventh thoracic leg of the same specimen, from the outer side; >< 24.

Fig. 3. Apseudes gracilis Norm. & Stebb.
Cephalothorax and three thoracic segments of a subadult female, from above; > tro.
Left cheliped of the same specimen, from the outer side; x 22.
Distal half of the fixed finger of the chela of the cheliped shown in fig. 3b, from the outer
side; >< 90.
Left second thoracic leg of the same specimen, from the outer side; x 22.

Fig. 4. Apseudes gracillimus n. sp.
Cephalothorax and the major part of the thorax of a subadult female, from above; x ro.
Seventh thoracic segment and abdomen of the same specimen, from above; >< 10,
Left cheliped of a subadult female, from the outer side; x 23.
Left second thoracic leg of the same specimen, from the outer side; x 23.

Left seventh thoracic leg of the same specimen, from the outer side; x 23,

Fig. 5. Heterotanats groenlandicus n. sp.
Female with marsupium, from above; x 16.
Carapace with antennulze of the same specimen, from above; >< 35.
Carapace and second thoracic segment with appendages of a female with marsupium, from
the left side; >< 47.
The fixed finger of the left chela of the same female, from the outer side; x< 94.
Left third thoracic leg of the last-named female, from the outer side; x 47.
Left seventh thoracic leg of the last-named female, from the outer side; >< 47.
End of abdomen with the left uropod of the same female, from the left side; >< 47.

128 CRUSTACEA MALACOSTRACA. II.

Fig. 6. Neotanais serratispinosus Norm. & Stebb.
Fig. 6a, Left cheliped of an adult female, from the outer side; >< 23.
— 6b. Fingers of the cheliped shown in fig. 6a, from the outer side; >< 67.

Plate II.

Fig. 1. Neotanais serratispinosus Norm. & Stebb. (Continued).
Fig. 1a. Terminal part of left third thoracic leg of an adult female, from the posterior side; x 74.
— 1b. Terminal part of left sixth thoracic leg of the same female, from the posterior side; >< 74.

— 1c. Terminal part of left seventh thoracic leg of the same female, from above; x 74.

Fig. 2. Meotanats giganteus n. sp.
Fig. 2a. Adult male, from above; >< 3.
— 2b. Anterior part of the carapace with the right antennula of the male, from above; x 8.
— 2c. Front end of the carapace with the ocular plate, the left antenna and the basal part of the
left antennula, of the male, from the left side; x 8. -
— 2d. Left cheliped of the male, from the outer side; >< 8.
— 2e. Right second thoracic leg, from the posterior side; >< 33/,.
— 2f. Terminal part of the leg shown in fig. 2e, from behind; x 24.
— 2g. Terminal part of right seventh leg, obliquely from above and in front; x 24.
— 2h. Last abdominal segment with the left uropod and the proximal part of the right uropod of

the male, from above; scarcely >< 7.

Fig. 3. Pseudotanats forcipatus LAlljeborg.
Fig. 3a. Body of an adult male, from above; x 36.
— 3b. Cephalothorax and the two anterior free thoracic segments with appendages of the adult
male, from the left side; >< 81.
— 3c. Front end of the carapace with the antennule of the adult male, from above; >< 81.
— 3d. Left seventh thoracic leg of the adult male, from the outer side; > 81.

— 3e. Three posterior abdominal segments with the uropods of an adult male, from above; > 81.

4. Pseudotanais abyssi n. sp.

Fig. 4a. Female with the marsupium not half developed, from the left side; >< 49.

— 4b. Body of a female with the marsupium fully developed, from above; >< 36.

— 4c. Front end of the carapace with left antennula and antenna of the adult female, from the
left side; >< 98.

— 4d. Left cheliped of an immature female, from the outer side; >< 98.

— 4e. Right second thoracic leg of an adult female, from the outer side; >< 91. The articulation
between fourth and fifth joint erroneously omitted.

— 4f Left third thoracic leg of an immature female, from the outer side; >< 98.

— 4g. Right fifth thoracic leg of an immature female, from the outer side; >< 98.

CRUSTACEA MALACOSTRACA. II. 129

Fig. 4h. Left first pleopod of an adult female, from behind; >< 94.

Fig.

4i.

Ta.

eb:

ire,

1d.

- 24.

2b.

2c.
2d.

2e.
af.

2g.
2h.

Right uropod of an adult female, from above; >< 145.

Fig. 5. Pseudotanais Lilyeborgit G. O. Sars.

Carapace with right antennula and half of left antennula of an ovigerous female, from
above; < 45.

Carapace with left antennula and half of the right antennula of an adult male, from above;
< 45-

Cephalothorax and the two anterior free thoracic segments with appendages of the adult
male, from the left side; >< 61.

Four posterior abdominal segments and uropods of the adult male, from above; x 57.

Left seventh thoracic leg of the adult male, from the outer side; >< 61.

Distal part of the leg shown in fig. 5e, from the outer side, x 146.

Distal part of seventh thoracic leg of a subadult male, from the outer side; x 146.

Fig. 6. Pseudotanats oculatus n. sp.
Distal part of left cheliped of a not fully adult female, from the outer side; >< 78.
Left second and third thoracic legs of a not fully adult female, from the outer side; > 78.
Left fourth thoracic leg of the same female, from the outer side; x 78.

Left seventh thoracic leg of the same female, from the outer side; x 78.

Plate III.

Fig. 1. Pseudotonats oculatus n. sp. (Continued).
Body of a female with the marsupial lamella small, from above; x< 24.
Female with the marsupial lamella small, from the left; > 25.
Front end of carapace with ocelli and left antennula and antenna of the female shown in
fig. 1b, from the left side; x 78.
Right uropod of the female shown in fig. 1a, from above; x 85.

Fig. 2. Pseudotanais affinis H. J. Hansen.

Carapace with left antennula of a female with marsupium from the Kara Sea, from above;
XS

Left antennula of the adult female from the Kara Sea, from the outer side: > 70.

Right uropod of the adult female from the Kara Sea, from above; x 83.

Left antennula and antenna of a female without marsupium from the “Ingolf” Stat. 103;
from the outer side; x 56.

Left chela of the same female from the “Ingolf’ Stat. 103, from the outer side; >< 56.

Left second thoracic leg of the same female from the “Ingolf” St. 103, from the outer side;
< 56.

Left third thoracic leg of the same “Ingolf” specimen, from the outer side; x 56.

Left seventh thoracic leg of the same “Ingolf” specimen, from the outer side; >< 56.

The Ingolf-Expedition. III. 3. 17

130 ° CRUSTACEA MALACOSTRACA. II.

Fig. 2i. Distal part of left third leg shown in fig. 2g, from the outer side; = 130.

— 2k. Left antennula and antenna of a female without marsupium belonging to the variety from
the “Ingolf” Stat. 25, from the outer side; >< 82.

— 21. Left antennula and antenna of a subadult male from the “Ingolf” Stat. 119, from the outer
side; >< 52.

— 2m. Left chela of an immature male from the “Ingolf” Stat. 119, from the outer side; >< 52.

— 2n. Left antennula and antenna of a subadult male of the variety from the “Ingolf” Stat. 25, from
the outer side; >< 82.

— 20. Left sixth thoracic leg of a subadult male from the “Ingolf” Stat. 119, from the inner side;

< 52.

Fig. 3. ? Pseudotanais affinis H.J.H.; adult Male.
Fig. 3a. Cephalothorax and second thoracic segment with appendages of the male from the “Ingolf”
Stat. 124, from the left side; >< 80.

— 3b. Four posterior abdominal segments and uropods of the same male, from above; x 80.

Fig. 4. Pseudotanats longipes un. sp.
Fig. 4a. Female with the marsupial lamellz quite small, from the left; >< 35.
— 4b. Anterior part of the body of the not quite full-grown female, from above; >< 35.
— 4c. Left antennula and antenna of the female shown in fig. 4a, from the outer side; x 55.
— 4d. Left chela of the same immature female, from the outer side; = 63.
— 4e. Left second thoracic leg of the same immature female, from the outer side; < 63.
— 4f£ Left third thoracic leg of the same immature female, from the outer side; >< 63.
— 4g. Distal part of the left fourth thoracic leg of the same female, from the outer side; x 100.
— 4h. Left seventh thoracic leg of the same immature female, from the outer side; >< 61.

-— 4i. Right uropod of an immature female, from above; x 84.

Fig. 5. Zyphlotanats irregularis n. sp.
Fig. 5a. Female, from above; >< 31.
— 5b. Cephalothorax and the two anterior free thoracic segments of a female without marsupium
from the “Ingolf” Stat. 117, from the left side; >< 73.
— 5c. Left chela of the specimen shown in fig. 5b, from the outer side; >< 128.
— 5d. Left seventh thoracic leg of the same female, from the inner side; < 73.

-—— 5e. Last abdominal segment with left uropod of the same female, from the left; >< 73.

Fig. 6. Zyphlotanais macrocephala n. sp.
Fig. 6a. The type-specimen, from above; < 43.
— 6b. Cephalothorax and the two anterior free thoracic segments of the single specimen, from the
left; >< 85.
— 6c. Second and third thoracic segments, from above; >< 84.
— 6d. Left seventh thoracic leg, from the outer side; x 85.

— 6e. Last abdominal segment with left uropod, from the left; >< 110.

Fig.

CRUSTACEA MALACOSTRACA. IL 131

Plate IV.
Fig. 1. Vyphlotanais pulcher nu. sp.

The single specimen (without marsupium), from above; >< 21.

Cephalothorax with antennulz, from above; x 45.

Cephalothorax and second thoracic segment with appendages, from the left side; >< 60.
Left third thoracic leg, from the outer side; >< 60.

Left fifth thoracic leg, from the outer side; >< 60.

Left seventh thoracic leg, from the outer side; x 60.

Left uropod, from above; >< 88.

Fig. 2. TZyphlotanais gracilipes un. sp.
Anterior part of the body with antennulz of the female without marsupium; x 44.
Carapace and anterior thoracic segments with appendages, from the left side; < 63.
Left fourth thoracic leg, from the outer side; x 63.
Right sixth thoracic leg, from the inner side; > 122.

End of abdomen with the mutilated left uropod — the endopod wanting — from above;
oe Ysa
Fig. 3. Zyphlotanais mucronatus n. sp.
Body of a female without marsupium (from the “Ingolf” Stat. 120), from above; >< 20.

Carapace with antennulze of the specimen shown in fig. 3a, from above; >< 37.

Cephalothorax and two anterior free thoracic segments with appendages of a female without
marsupium from the “Ingolf” Stat. 119, from the left side; =< 48.

Left chela of the female shown in fig. 3c, from the outer side; x 96.

Left sixth thoracic leg of the last-named female, from the outer side; x 48.

Distal half of the leg shown in fig. 3e, from the outer side; x go.

Last abdominal segment with left uropod of the last-named female, from the left side; >< 57.

Left antennula and antenna of a subadult male from the “Ingolf” Stat. 120, from the left

side; x 48.

Fig. 4. Zyphlotanais eximius un. sp.

Immature, somewhat contracted female, from above; >< 35.

Cephalothorax and the two anterior free segments with appendages of the largest female
without marsupium, from the left side; x 80. .

Seventh right thoracic leg of the last-named female, from the outer side; x 80.

Right uropod of the specimen shown in fig. 4a, from above; x 88.

Cephalothorax and two anterior free segments with appendages of the immature male, from
the left side; >< 77.

Left sixth thoracic leg of the immature male, from the outer side; >< 77.

Last abdominal segment with left uropod of the immature male; x 77.

Fig.

Fig.

24a.

2b.

ac.

3a.

3b.

a6.

CRUSTACEA MALACOSTRACA. IL.

Fig. 5. Zyphlotanais penicillatus G. O. Sars.
Cephalothorax and anterior free segments with appendages of a female without marsupium,
from the left side; >< 80.
Left sixth thoracic leg of the same female, from the outer side; =< 8o.
Last abdominal segment with left uropod of the same female, from the left side; x 80.

Left antennula of an immature male, from the outer side; >< 80.

Fig. 6. Zyphlotanais tnermis n. sp.
Body of a female without marsupium, from above; >< 22.
Carapace with antennulee of the same female, from above; >< 42.
Cephalothorax and anterior thoracic segments with appendages of a female without marsupium
from the “Ingolf’ Stat. 139, from the left side; x 55.
Left chela of the specimen shown in fig.6c, from the outer side; >< 100.
Left sixth thoracic leg of the female shown in fig.6c, from the outer side; x 55.
Distal half of the leg shown in fig.6e, from the outer side; x 138.

Right uropod of the specimen shown in fig.6a, from above; >< 76.

Fig. 7. Zyphlotanais variabilis un. sp.
Female without marsupium from the “Ingolf” Stat. 102, from above; < 22. The legs omitted.
Left sixth thoracic leg of the adult female shown in fig.2a on the next plate, from the
outer side; >< 50.
Major distal part of left seventh leg of the last-named female, from the outer side; x 110.

Left uropod of the last-named adult female, from the outer side; >< 50.

Plate V.
Fig. 1. Zyphlotanats mucronatus n. sp.
Left antennula and antenna of a subadult male, from the outer side; >< 48. (This figure, which

is found as fig.3h on PI.IV, has by an error in the arrangement been reproduced here again.)

Fig. 2. Zyphlotanars variabilis n. sp. (Continued.)
Cephalothorax and anterior thoracic segments of an adult female from the “Ingolf” Stat. 102,
from the left side; x 50. Z. parasitic Copepod, measuring o.1 ™ in length.
Left antennula and antenna of a female without marsupium from the “Ingolf” Stat. 105, from
the outer side; >< 50.
Cephalothorax and anterior thoracic segments with appendages of a subadult male from the

“Ingolf” Stat. 105, from the left side; x 55.

Fig. 3. Zyphlotanais tenuicornis G. O. Sars.
Left antenna, setee omitted, of a female from Norway (a co-type of G. O.Sars), from the
outer side; >< 140.
Major distal part of left second thoracic leg of a female from Norway, from the outer side; >< 140.
Left third leg of the last-named female, from the outer side; >< 140.

Fig.

6a.

6b.

CRUSTACEA MALACOSTRACA. II. 133

Fig. 4. Zyphlotanats trispinosus n. sp.
Female without marsupium, from above; x 21. The legs omitted.
Cephalothorax and anterior thoracic segments with appendages of a female without mar-
supium, from the left side; x 82.
Left antenna of the last-named female, from the outer side; + 140. The sete omitted.
Major distal part of left second thoracic leg of the specimen shown in fig. 4b, from the
outer side; >< 140.
Right seventh thoracic leg of a female without marsupium, from the outer side; > 205.

Left uropod of the female shown in fig. 4b, from the outer side; x 82.

Fig. 5. Zyphlotanais profundus nu. sp.
Female without marsupium, from above; x 21. The legs omitted.
Left antennula of the same specimen, from above; >< 75.
Left antennula and antenna of a female without marsupium, from the outer side; >< 78.
Left uropod of a female without marsupium, from the outer side; >< 80.
Cephalothorax and anterior thoracic segments with appendages of a subadult male, from the

outer side; < 78.

Fig. 6. Zyphlotanats spinicauda nu. sp.

Cephalothorax and three anterior thoracic segments of the single specimen, a female without
marsupium, from above; >< 30.

Cephalothorax and anterior thoracic segments with appendages of the female without mar-
supium, from the left side; >< 45.

Left antennula and antenna, from the outer side; x 83.

Distal half of left cheliped, from the outer side; x 83.

Left second thoracic leg, from the outer side; < 83.

Left third thoracic leg, from the outer side; x 83.

Right sixth thoracic leg, from the outer side; >< 83.

Last abdominal segment with the uropods, from above; x 60.

Fig. 7. Zyphlotanais grandis ux. sp.
Body of the single specimen, probably an immature male, from above; < 13.
Cephalothorax and anterior thoracic segments with appendages of the specimen mentioned,
from the side and somewhat obliquely from above; x 38.
Left seventh thoracic leg, from the outer side; x 38.
Major distal part of the leg shown in fig.7c, from the outer side; x 135.
Last abdominal segment with left uropod, from the outer side; x 54.

_ Fig. 8 Zyphlotanais plebejus n. sp.
Body of a female without marsupium, from above; x 16.
Left antennula and antenna of a female without marsupium, from the outer side; x 58.

Left cheliped of a female without marsupium, from the outer side; > 58.

CRUSTACEA MALACOSTRACA. II.

Fig.

Fig.

Batak

8e.

Bt
8g.

ga.

~ Ta

ric

Left second thoracic leg of a female without marsupium, from the outer side; x 58.

Left fourth thoracic leg of the same female, from the outer side; x 58.

Left fifth thoracic leg of the same female, from the outer side; x 58.

Last abdominal segment with left uropod of a female without marsupium, from the left
side; x. 58.

Lig O74 vphlotanais inequipes i. sp.
Right seventh thoracic leg of a female without marsupium, from the outer side; >< 80.

Left uropod of a female without marsupium, from the outer side; > 8o.

Plate VI.

Fig. 1. Zyphlotanats inequipes (Continued.)
Body of a female without marsupium, from above; >< 25.
Right antennula of the same female, from above; >< 8o.
Cephalothorax and anterior thoracic segments with appendages of a female without mar-

supium, from the left side; >< 80.

Fig. 2. Zyphlotanais finmarchicus G. O. Sars.
Left antennula and antenna of a female without marsupium from the Sabine Island, from
the left side; = 84.

Left uropod of the same female, from the outer side; >< 84.

Fig. 3. Zyphlotanats mixtus n. sp.
Body of a female without marsupium from the “Ingolf’ Stat.117, from above; >< 27.
Cephalothorax and anterior thoracic segments of a female with marsupium (the marsupium
itself omitted) from the “Ingolf” Stat.117, from the left side; x< 82.
Left antennula of a subadult male from the “Ingolf” Stat.117, from the left side; >< 82.
Second thoracic segment (left leg omitted) of a female without marsupium from the same
station, from the left side; x 82.

Left sixth thoracic leg of the female shown in fig. 3b, from the outer side; >< 82.

Fig. 4. Zyphlotanais solidus un. sp.
The single specimen, a female without marsupium, from above; >< 21. Most of the append-
ages omitted.
Carapace with antennule, from above; >< 32.
Cephalothorax with appendages, from the left side; x 52.
Left second and third thoracic legs, from the outer side; >< 52.
Right seventh thoracic legs, from the outer side; = 52.

Last abdominal segment with right uropod, from above; x 52.

Fig.

5m.

5n.

50.

. 6a.

6b.
6c.
6d.
6e.

CRUSTACEA MALACOSTRACA. II.

135

Fig. 5. <Agathotanais Ingolfi n. gen., n. sp.

Largest female without marsupium, from above; >< 15.

Largest female without marsupium, from the left side; x 16.

Front end of the cephalothorax with left antennula and antenna ot the last-named female,
from the left side; < 53.

Both mandibles of a female without marsupium, from below; > 93. / left mandible.

Paragnatha of the last-named female, from below; >< 93.

Left maxillula of the last-named female, from below; x 93.

Maxillipeds, with the epipods omitted, of the last-named female, from below; >< 93.

Left chela of the female shown in fig.5b, from the outer side; >< 53.

Left third thoracic leg of the female shown fig.5b, from the outer side; < 53.

Left seventh thoracic leg of the last-named female, from the outer side; >< 53.

Two posterior abdominal segments with left uropod of the last-named female, from the left
side; >< 68.

Two posterior abdominal segments with uropods of another female without marsupium,
from below; < 66.

Front end of the head with left antennula and antenna of a subadult male, from the left
side; x 61.

Posterior part of the thorax, seventh left thoracic leg and abdomen with pleopods and left

uropod of a subadult male, from the left side; >< 36.

Fig. 6. Leptognathia multiserrata nu. sp.
Right antennula and antenna of a female without marsupium, from the outer side; >< 85.
Carpus and chela of right cheliped of the same female, from the outer side; < 85.
Second right thoracic leg of the same female, from the outer side; >< 85.
Sixth right thoracic leg of the same female, from the outer side; >< 85.
Five posterior abdominal segments with the right uropod and the pleopod of fifth segment
of the same female, from the outer side; >< 46. Pleopods of second, third and fourth
segments omitted. 3

Fig. 7. Leptognathia Sarsii H. J. Hansen.

Anterior part of the cephalothorax of a female from Klaksvig (Faroe Islands), from the
outer side; >< 65.

Left chela of an other female from the same locality, from the outer side; x 8s.

Left second thoracic leg of a third female from the same locality, from the outer side; x 58.

Left seventh thoracic leg of the last-named female, from the outer side; x 58.

Abdomen with left uropod and the pleopod of second segment of a female from the same
locality, from the left side; x 39. Four pleopods omitted in order to show the ventral
protuberances.

End of abdomen with left uropod — sete omitted — of another female from the same

locality, from the left side; x 55.

Fig. 4a.

CRUSTACEA MALACOSTRACA. II.

Plate VII.
Fig. 7. Leptognathia gracilis Kroyer.
Anterior part of the cephalothorax with appendages of a female, from the left side; x 65.
Left chela of a subadult male, from the outer side; x 84.
Distal part of left second thoracic leg of a female, from the outer side; x 80.

Left uropod of a female, from the outer side; x 80.

Fig. 2. Leptognathia Hanseni Vanhoffen.

Anterior part of the cephalothorax with appendages of a female from the mouth of the
Ameralik Fjord, from the left side; x 63.

Left second thoracic leg of the same female, from the outer side; x 76.

Left sixth thoracic leg of the same female, from the outer side; x 76.

Five posterior abdominal segments with left fourth pleopod and left uropod of a female from
the same locality, from the left side; * 41.

Left cheliped of a subadult male from the same locality, from the outer side; * 76.

Anterior part of the cephalothorax with appendages of an adult male from the mouth of the
Ameralik Fjord, from the left side; < go.

Major part of the left chela of the same male, from the outer side; < 180.

Distal part of the hand with the base of the fingers of the same chela, from the inner
side; < 170.

Left second thoracic leg of the same male, from the outer side; x go.

Major distal part of left seventh thoracic leg of the same male, from the outer side; >< go.

Posterior end of abdomen with left uropod of the same female, from the outer side; X go.

Fig. 3. Leptognathia longiremis LAlljeborg.

Anterior part of the cephalothorax with appendages of a female without marsupium from
the “Ingolf” Stat. 25, from the outer side; < 62.

Left second thoracic leg-of the same female, from the outer side; x 62.

Distal part of left fifth thoracic leg of the same female, from the outer side; X 62.

Abdomen with left fourth pleopod and left uropod of the same female, from the left side;
> 40. The other pleopods omitted in order to show the ventral tubercles of the segments,

End of abdomen with left uropod — sete omitted — of the same specimen, from the outer
side; X 92.

Fig. 4. Leptognathia inermis u. sp.

Anterior, part of the cephalothorax with appendages of an ovigerous female, from the
“Ingolf” Stat.115, from the left side; 86.

Distal half of left cheliped of another female from the same station, from the outer side;
< 86. ipl

Left second thoracic leg of the specimen shown in fig. 4a, from the outer side; < 86,

Major distal part of left second thoracic leg of another female, from the outer side; x 86.

' Fig. 5a.

CRUSTACEA MALACOSTRACA., II. 137

Left sixth thoracic leg of the female possessing the chela shown in fig. 4b, from the inner
side; >< 86.

Abdomen with second and fifth left pleopods and left uropod of the female shown in fig. 4a,
from the left side; >< 82.

Left cheliped of a female from Cape Dalton, from the left side; =< 84. The movable finger
differs from that in specimens from other localities (figs.4a and 4b) in having three feeble

indentations on the anterior margin.

Fig. 5. Leptognathia brachiata nu. sp.

Carapace with antennulz and second thoracic segment of a female without marsupium from
the “Ingolf” Stat. 25, from above; >< 35.

Cephalothorax and second thoracic segment with appendages of a female with marsupium
from the “Ingolf” Stat. 25, from the left side; >< 47.

Left antennula and antenna of the last-named specimen, from the outer side; >< 85.

Left cheliped of the last-named specimen, from the outer side; >< 85.

Left second thoracic leg of a female without marsupium from the same station, from the
outer side; >< 85.

Left sixth thoracic leg of the last-named female, from the outer side; x 85.

Three posterior abdominal segments of the specimen mentioned at fig.5a, from above; > 46.

Abdomen with appendages of a female with marsupium from the “Ingolf” Stat. 25, from the
left side; < 46.

Fig. 6. Leptognathia alba n. sp.

Left antennula and antenna of the single specimen, from the outer side; >< 55.

Left cheliped, from the outer side; < 8s.

Left second thoracic leg, from the outer side; > 58.

Left seventh thoracic leg, from the outer side; x 58.

Abdomen with left fifth pleopod and left uropod, from the outer side, x 33. The other

pleopods omitted in order to show the characteristic ventral tubercles.

Fig. 7. Leptognathia hastata n. sp.

Left antennula and antenna of a female without marsupium from the “Ingolf” Stat. 102, from
the outer side; >< 62.

Left cheliped of the same specimen, from the outer side; >< 62.

Left second thoracic leg of the same specimen, from the outer side; >< 88.

Left fifth thoracic leg of the same specimen, from the outer side; >< 88.

Distal part of left seventh thoracic leg of the same specimen, from the outer side; x 172.

Abdomen with left first and fifth pleopods and left uropod (with the sete omitted) of the
same specimen, from the left side; >< 4o.

End of abdomen with left uropod of the same specimen, from the outer side; x 65.

Three posterior segments of the abdomen and left uropod — the sete omitted — of another

female without marsupium from the “Ingolf” Stat. 102, from the left side; x 4o.

The Ingolf-Expedition, IT. 3. 18

CRUSTACEA MALACOSTRACA. IL.

Fig. 2a.

Fig. 5a.
— 5b.

Plate VIII.

Fig. 1. Leptognathia armata n. sp.

Left antennula and antenna of a subadult male from the “Ingolf” Stat. 36, from the outer
side; >< 59.

Left cheliped of the same subadult male, from the outer side; >< 59.

Left second thoracic leg of the same subadult male, from the outer side; >< 509.

Distal part of second thoracic leg of the female from the “Ingolf” Stat. 22, from the outer
side; >< 100.

Left sixth thoracic leg of the subadult male, from the inner side; < 59.

Abdomen with second left pleopod and left uropod of the female, from the left side; >< 32.
The other pleopods omitted.

Fig. 2. Leptognathia Amdrupti n. sp.
Left antennula of a female with marsupium, from the outer side; x 60.
Left cheliped of the same female, from the outer side; =< 60.
Left second thoracic leg of the same female, from the outer side; > 60.

Fig. 3. Leptognathia tuberculata n. sp.

Cephalothorax aud sécond thoracic segment of a female without marsupium, from the left
side; >< 56.

Left second thoracic leg of a female with marsupium, from the outer side; < 83.

Left sixth thoracic leg of the last-named female, from the inner side; x< 83.

Abdomen with first, third and fifth left pleopod and left uropod of a female, from the left
side; < 48.

Left first pleopod of the female, from behind; = 140.

Left first pleopod of a subadult male, from in front; x 140.

Fig. 4. Leptognathia uncinata n. sp.
Left antennula of a female without marsupium, from the outer side; >< 93.
Left cheliped of the same specimen, from the outer side; >< 93.
Left second thoracic leg of the same specimen, from the outer side; < 93.
Portion of abdomen with left fourth pleopod of the same female, from the outer side; < 88.
End of abdomen with left uropod of the same female, from the left side; < 93.
Major part of cephalothorax with appendages of an adult male, from the left side; < 83.
Left second thoracic leg of the same male, from the outer side; < 83.
Major part of left sixth thoracic leg of the same male; x 83.

Two posterior abdominal segments with left uropod of the same male, from the outer side; >< 83.

Fig. 5. Leptognathia manca G. O. Sars.
Cephalothorax and second segment of a female without marsupium, from the left side; >< 86.

Abdomen of a female with marsupium, from the left side; x 86.

Fig. 2a.

CRUSTACEA MALACOSTRACA. IL. 139

Cephalothorax of a subadult male, from the left side; >< 86.
Last thoracic segment (leg omitted) and abdomen with left uropod and fourth left pleopod
— the other pleopods omitted — of the same subadult male, from the left side; < 60.

Fig. 6. Leptognathia subequal n. sp.
Female without marsupium from the “Ingolf” Stat.139, from above; < 34.
Cephalothorax and second segment with appendages of a female with marsupium from the
same station, from the left side; < 80.
Left cheliped of another female from the same station, from the outer side; >< 135.
Three posterior abdominal segments of the female shown in fig. 6b, from the left side; >< 89.
Four posterior abdominal segments with pleopods and left uropod of an immature male or
more probably a female without marsupium from the “Ingolf” Stat. 4, from the left side; x 89.
Left antennula and antenna of a subadult male from the “Ingolf” Stat. 139, from the left

side; >< 89.
: Fig. 7. Leptognathia ventralis n. sp.

Female without marsupium from the “Ingolf” Stat. 115, from above; >< 27.

Cephalothorax and second segment — only the basal part of its left leg drawn — of a
female with marsupium from the same station, from the left side; < 86.

Mandibles of an immature male, from above; = 142. /. left mandible.

Maxillipeds of the last-named specimen, from below; >< 142.

Left third thoracic leg of a female with marsupium from Stat. 115, from the outer side; >< 86.

Left seventh thoracic leg of the same female, from the outer side; < 86.

Abdomen of a female from Stat. 115, from the left side; < 59.

Left second thoracic leg of a female without marsupium from Stat. 38, from the outer side; > 86.

Cephalothorax and second segment with appendages of a subadult male from Stat. 115, from
the left side; 86.

Three posterior abdominal segments with left pleopods and uropod of a subadult male, from

the outer side; >< 86.

Plate IX.
Fig. 1. Leptognathia tenella un. sp.

Female without marsupium, from above; x 33.

Cephalothorax and second thoracic segment of a female without marsupium, from the left
side; >< 95.

Left seventh thoracic leg of the same female, from the outer side; >< 95.

Abdomen of the same female, from the left side; >< 95.

Three posterior abdominal segments of the female shown in fig. 1a, from above; >< 84. Sete

of right uropod omitted.

Fig. 2. Leptognathia acanthifera nu. sp.

Female without marsupium, from above; < 31.
18*

140

Fig. 2b.

Ts.

38:

CRUSTACEA MALACOSTRACA. II.

Cephalothorax and the two following segments of a female without marsupitum, from the
left side; < 84.

Left fifth thoracic leg, from the outer side; < 84.

Abdomen of the female shown in fig. 2b, from the left side; >< 84.

Fig. 3. Leptognathia breviremis Lilljeborg.

Cephalothorax and second thoracic segment of a female without marsupium from the “In-
golf? Stat. 117, from the left side; x 83. A minute parasitic Copepod is attached to the
outer side of second joint of second thoracic leg. .

Four posterior abdominal segments with left fourth pleopod and left uropod of the above-
named female, from the left side; < 83.

Abdomen of an ovigerous female from Norway, from the left side; = 83. Pleopods excepting
the third and the sete of the uropod omitted.

Anterior part with appendages of an adult male from the “Ingolf’ Stat. 36, from the left
side; < 84.

Left sixth thoracic leg of the same male, from the outer side; >< 84.

Sixth and seventh thoracic and all abdominal segments of the same male, from the left side;
>< 84. Thoracic legs and the pleopods of first, second and fourth abdominal segments
omitted.

Sixth abdominal segment with left uropod of an adult male from the “Ingolf’ Stat. rox
from the left side; x 80.

Fig. 4. Leptognathia crassa n. sp.

Female without marsupium, from above; =< 29.

Cephalothorax and second thoracic segment with appendages of a female, from the left
side; >< 60,

Left sixth thoracic leg of another female, from the outer side; < 79.

Abdomen of the female shown in fig. 4b from the left side; >< 60. Pleopods omitted ex-
cepting the third.

Three posterior abdominal segments of the last-named female, from below; < 60. The

pleopods on the left side of the figure omitted.

. Fig. 5. Leplognathia polita n. sp.

Female without marsupium, from above; x< 17.

Cephalothorax and second thoracic segment of the same female, from the left side; >< 36.
Left second thoracic leg omitted excepting its most proximal part.

Major part of left chela of the same specimen, from the outer side; x 80.

Right second thoracic leg of the same female, from the outer side; >< 50.

Left sixth thoracic leg of the same female, from the outer side; =< 50.

Five posterior abdominal segments with left fifth pleopod and left uropod of the same spec-
imen, from the outer side; >< 36.

CRUSTACEA MALACOSTRACA. II. 14t

See a
tb.

Ic.

rd.

re

rf.

Ig.

th.

ee
2b.

2c.

2d.

2e.
af.

22.
2h.

2i.

ak.

Fig. 6. Leptognathia vicina nu. sp.

Subadult male from the “Ingolf” Stat. 28, from above; x 25.

Cephalothorax and second thoracic segment with appendages of a female without marsupium
from the same station, from the left side; >< 57.

Mandibles of a female, from below; < 90. Z left mandible.

Molar processes of the same mandibles, from below; < 315.

Left maxillula of the same female, from below; >< go.

Left cheliped, removed from the animal and seen from the outer side; >< 65.

Right sixth thoracic leg of a female, from the outer side; >< 57.

Four posterior abdominal segments with fourth pleopod and left uropod of the female shown
in fig. 4b, from the outer side; >< 57.

Left antennula of a subadult male from Lat. 66° 49' N., Long. 56° 28’ W., from the left side; 82.

Plate X.
Fig. 1. Leptognathia profunda vn. sp.

Female without marsupium, from above; x 26.

Anterior half of a female without marsupium, from the left side; ~«< 56.

Left cheliped of another female, from the outer side; x 97.

Left second thoracic leg of a third female, from the outer side; < 97.

Left sixth thoracic leg of the last-named specimen, from the outer side — distal half of the
leg somewhat turned; >< 97.

Left first pleopod of a female, from in front; x 95.

Four posterior abdominal segments with appendages of the female shown in fig. rb, from
the left side; < 56.

Left uropod of another female, from the outer side; < 97.

Fig. 2. Leptognathia latiremis nu. sp.
Female without marsupium from the “Ingolf” Stat. 58, from above; < 26.
Left antennula and antenna of a female without marsupium from the same station, from the
outer side; < 86.-
Left antennula of the female shown in fig. 2a, from above; < 48.
Left antennula of an immature male from the same station, from above; =< 48.
Labrum and both mandibles of a female; from below; >< 235.
Maxillipeds of the last-named specimen, from below; < 235.
Left cheliped of a female without marsupium, from the outer side; < 86.
Distal part of left second thoracic leg of the last-named specimen, from the outer side; > 86.
Left third thoracic leg of the last-named specimen, from the outer side; x 86.
Left seventh thoracic leg of the same specimen, from the outer side; < 86, The distal half

of the leg somewhat turned.

CRUSTACEA MALACOSTRACA. ITI.

Fig. 21.

— 2m,

sn QE.

Fig. 3a.

Fig. 4a.

First left pleopod of a female, from in front; x 86.

Posterior part of abdomen with right uropod of a female, from above; >< 52.

Posterior part of abdomen of a young specimen with the seventh pair of thoracic legs and
the pleopods still wanting, from the left side; =< 86.

Fig. 3. Leptognathia glacialis un. sp.
Distal half of left cheliped, from the outer side; x 86.
Three posterior abdominal segments, from the left side; < 86.

Fig. 4. Haplocope linearis n. sp.

A full-grown female, from above; X 32. The right uropod in this specimen was abnormally
short.

Cephalothorax and second thoracic segment with appendages of a female without marsupium,
from the left side; x< go.

Mandibles of a female, from below; >< 200. / left mandible.

Right sixth thoracic leg of the female shown in fig. 4b, from the outer side; >< go.

Third left pleopod of a female with marsupium, from in front; >< 108.

Major part of abdomen with fourth and fifth left pleopod — the other pleopods omitted — and
left uropod of a female with marsupium, from the left side; x 75.

Fig. 5. Leptognathiella abyssi n. gen., 0. sp.

Female withont marsupium, from above; x 26.

Anterior part of the same female, from above; x 56.

Abdomen and posterior part of the thorax of the same female, from above; = 44.

Left antennula and antenna of a female, from the outer side; x 82.

Left sixth thoracic leg of a female, from the outer side; x 82.

Abdomen and major part of last thoracic segment of a female, from the left side; < 56.

Cephalothorax and two anterior thoracic segments with appendages of a subadult male,
from the left side; x 82.

Left fifth thoracic leg of the subadult male, from the outer side; < 82.

Abdomen with fourth and fifth left pleopod and uropod of the subadult male; < 56. Anterior
pairs of pleopods omitted.

Fig. 6. Cryptocope Voringii G. O. Sars.
Cephalothorax of a female without marsupium from the “Ingolf”’ Stat. 138, from the left
side; >< 31.
Distal part of the chela of the same female, from the outer side; < 53.
Left third thoracic leg of the same female, from the outer side; >< 31.
Abdomen of the same female without marsupium, from the left side; >< 31.

Fig.

Ic,

CRUSTACEA MALACOSTRACA. II. 143

Plate XI.

Fig. 1. Cryptocope arctica H. J. Hansen.

Female without marsupium from the “Ingolf” Stat. 25, from above; x< 26.

Cephalothorax and second thoracic segment with appendages of an ovigerous female from
Henry Land, from the left side; >< 47.

Left chela of a female without marsupium from the “Ingolf” Stat. 25, from the outer side;
ar i i

Left sixth thoracic leg of the last-named specimen, from the outer side; >< 50.

Abdomen and last thoracic segment of the female shown in fig. 1b, from the left side; > 47.
The thoracic leg excepting its basal part and second, third and fourth left pleopod omitted.

Abdomen with small pleopods — second, third and fourth pleopod omitted — of a large

female without marsupium from the “Ingolf” Stat. 25, from the left side; >< 52.

Left antennula of a subadult male from Henry Land, from the left side; >< 47.

Abdomen — left second, third and fifth pleopod omitted — and posterior part of the thorax
of a subadult male from Henry Land, from the left side; >< 47.

Fig. 2. Cryptocope arctophylax Norm. & Stebb.

Subadult male from Stat. 24, from above; >< 16.

Left antennula of the same subadult male, from the outer side; > 57.

Major part of left chela of the same subadult male, from the outer side; x 56.

Abdomen — first, second and fourth pleopod omitted — and seventh thoracic segment of
the same subadult male, from the left side; < 32.

Left antennula and antenna of an immature female from Stat. 24, from the left side; > 57.

Distal part of left sixth thoracic leg of the same immature female, from the outer side;
x< 80, |

Abdomen and end of thorax of the same immature female, from the left side; =< 36.

Cephalothorax and anterior part of thorax of an adult male from Stat. 36, from the left
side; >< 35.

Left chela of the adult male, from the outer side; >< 61.

Major part of abdomen — the three anterior pleopods omitted — of the same adult male,

from the left side; >< 33.

Fig. 3. Zanaella ochracea u. sp.
Female without marsupium, from above; x 21.
Cephalothorax and the two anterior thoracic segments with appendages of the same female,
from the left side; >< 46.
Major part of left chela of the same specimen, from the outer side; x 85.
Distal part of left third thoracic leg of the same female, from the outer side; >< 80.
Left seventh thoracic leg of the same female, from behind; x 8o.
Abdomen — first, third and fourth pleopod omitted — and seventh thoracic segment of the

same female; < 32.

CRUSTACEA MALACOSTRACA. II.

Fig. 4. Zanaella unguicillata Norm. & Stebb.
Cephalothorax and two anterior thoracic segments with appendages of a female without
marsupium, from the left side; x 4o.
Major part of left chela of the same female, from the outer side; < 85.
Left sixth thoracic leg of the same female, from in front; >< 80.

Last thoracic segment and abdomen of the same female, from the left side; >< 31.

Fig. 5. Strongylura minima n. sp.
Subadult male, from above; < 55.
Cephalothorax and two anterior thoracic segments with appendages of the subadult male,
from the left side; >< 95.
Four posterior abdominal segments — third and fourth left pleopod omitted — from the
side; >< 95.

Cephalothorax of a female without marsupium, from the left side; >< 91.

Plate XII.
Fig. 1. Strongylura cylindrata G. O. Sars.

Female without marsupium from the “Ingolf’ Stat.113, from above; < 14.

Cephalothorax of a female without marsupium from the “Ingolf’ Stat. 113, from the left
side; < 52.

Left third thoracic leg of the female from Stat. 113, from the outer side; >< 81.

Left seventh thoracic leg of the female from Stat.113, from the outer side; =< 8x.

Cephalothorax and second thoracic segment of the subadult male from the “Ingolf” Stat. 24,
from the left side; < 60.

Posterior part of abdomen of the subadult male from Stat. 24, from the left side; >< 60.

Left antennula and antenna of a female without marsupium from Norway, from the left
side; < 60.

Left second thoracic thoracic leg of the same female from Norway, from the outer side; >< 81.

Left sixth thoracic leg of the same female from Norway, from behind; x 8r1.

Last abdominal segment of the same female from Norway, from the left side; < 58.

Left pleopod of the abdomen shown in fig. 1k, from the outer side: >< 175.

Fig. 2. Strongylurella indivisa n. gen., 0. Sp.
Female without marsupium, from above; < 36.
Cephalothorax and second thoracic segment of the same specimen, from the left side; < 91.
Left sixth thoracic leg of the same specimen, from the outer side; x 9I.
Five abdominal segments of the same female, from the left side; x 80.

Four posterior abdominal segments of the same female, from above; x 54.

Fig. 3. Paranarthrura insignis n. gen., 1. sp.

Female without marsupium from the “Ingolf” Stat. 25, from above; >< 21.

CRUSTACEA MALACOSTRACA. II. 145

Fig. 5a.
5b.

31

Cephalothorax and anterior thoracic segments of a female without marsupium from the same
station, from the left side; = 56.

Labrum and mandibles of a female, from below; > 130.

Both mandibles in another position, from below; >< 200.

Left maxillula of the last-named female, from below; 130. '

Maxillipeds — epipods omitted — of the same female, from below; >. 130.

Left seventh thoracic leg of an ovigerous female, from behind; = 56.

Seventh thoracic segment — the leg omitted — and abdomen of a female, from the left
side; < 47.

Seventh thoracic segment and abdomen of a female, from above; x< 42.

Left antennula and antenna of a subadult male from Stat. 25, from the left side; >< 56.

Left cheliped of a subadult male, from the left side; >< 81.

3m. Seventh thoracic segment and abdomen of a subadult male from Stat. 25, from the left side;

5c.

>< 47. Left thoracic leg and third and fourth pleopods omitted.

Fig. 4. Paranarthrura subtilis un. sp.
Female without marsupium, from above >< 34.
Cephalothorax and second thoracic segment with appendages of a female without marsupium,
from the left side; < 89.
Seventh thoracic segment and abdomen of the same female without marsupium, from the
left side; >< 80.
Seventh thoracic segment and abdomen of another female without marsupium, from above;

< 89.
Fig. 5. Paranarthrura clavipes un. sp.

Young specimen with the seventh thoracic segment only half developed, from above; x 35.
Cephalothorax and second left leg of an immature male, from the left side; x 82.
Abdomen and posterior part of the thorax of the same immature male, from the left side;

>< 82. Major part of sixth leg and first, second and fourth pleopod omitted.

The Ingolf-Expedition. III, 3. 19

EL. J. Hansen: Crustacea Malacestraca I. PI. 1.

L Apseudes viciiits n.sp.

4. A. gracillimus 1. sp.

3A. gracilis Norm.& Stebb.

6. Neotanats serratispinosus Norms stebs.

2. A. teniis w. sp.

3. Heterotanais groenlandicus mn. sp.

3
i
.

IN MSller se.

HJ. Hanser: Crustacea Malacostraca Il PI I

1. Neotanais serratispinosus Norm.4Stebb. 2.N. siganteus n.sp.

¢. PB abyssi rsp. IP Liljeborgii Gas. 6. P. oewlatus n.sp.
HJ Hansen del.

WS flavin: Critdnons Malacutiace UPL

1 Pseudotanais oculatus n.sp. 2. P atfinis HIH. 3? PB aftinis HIH,é ad.

4. BP longipes n. sp. &. Typhlotanais trregularis n.sp. 6 T. macrecephala n. sp.
HTHansen del. IN. Miller se.

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Q Q The Ingolt Expedition Il. 3. HJ. Hansen‘ Crustacea Malacostraca Il. PLW.

1. Typhlotanais pulcher n. sp. 2. TL gracilipes ny. 3.F mucronatus n.sp. ¢.Teximius n.sp.

5.2. penicillatus 6.08. 6. Tinermis n.sp. 7. I. variabilis n.sp.
HI Hansen del. LN Miller se,

4. Typhlotanats mucronatus n. sp. 2.2. variabilis n sp
3. Tprotundus n. sp. 6. 7. spinicauda n, sp. 72. grandis n. sp.

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1. Typhlotanais ineguipes nsp. 2.0 finmarchicus 608. 3. U mixtus nz. sp. 4.7 solidus n.sp.

J Agathotanaés Ingolfi n gen,n sp. 6. Leptognathia multiserrata n.sp. 7. L. Sarsti HSH.
HSHansen ded. IN Miller se.

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eaten ron Races

HJ. Hansen: Crustacea Malacostraca I. Pl. VII.

1 Leptognathia gracilis kr. 2. L.Hanseni Vanhotfen. 3. L. longiremis Liles. 4. Linermis n.sp.

&L.brachiata nsp. 6. L.alba n. sp. 7L.hastata n. sp. :
HidHansen del. ‘ : INMller se.

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HS. Hanserv: Crustacea Malacostraca Il. Pl. Vill.

Lteptognathia armata n.sp. 2. L.Amdrupti n.sp. 3.1L. tuberculata n.sp. 4. L.uncinata n.sp.
o.L.manca G08. 6.l.subequalis w.sp. 7. L. ventralis rn. sp.
iHsHansen del. LN. Meller se.

as de cine
.

HJ. Hanser: Crustacea Malacostraca II. PU. IX.

1 Leptegnathia tenella n.sp. 2.1. acanthifera nsp. 3.1. breviremis Lilijed. $l. crassa r. sp.

JL. polita n. sp. CL. vicina n. sp.
= HidHansen del. r LN. Mller ve.

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‘The Ingolf Expedition IL 3. HJ Hansen: Crustacea Malacostraca II. Pl. X.

>

1. Leptognathia protunda wn. sp. 2. latiremis n.sp. BL. glacialis n.sp. 4. Haplocope linearis n.sp.
J leptognathiella abysst’ n.gen,n.sp. 6. Cryptocope Voeringti GAs.

HdHansen det. TN. Méller se.

HLS. Hansen: Crustacea Malacostraca Il. PL XI.

1. Cryptocope aretica HWiH. 2. C. arectophylax Normstebb. 3 Tanaella ochracea n. sp.

4.7 ungutetllata Nerm.4 $tedd. 5. Strongylura minima n. sp. 5
Hd. Hansen del TN. Métller se.

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JIEJ. Hansen: Crustacea Malacostraca Il. Pl. XI.

1. Strongylura eylindrata @08. 2. Strongylurella indivisa n.gen.,n.sp. 3. Paranarthrura insignis n.gen., n. sp.
§. PB. subtilis n. sp. SP. clavipes nap.

LN. Méller se.

THE INGOLF-EXPEDITION

* 1895—1896,

THE LOCALITIES, DEPTHS, AND BOTTOMTEMPERATURES OF THE STATIONS.

Depth Depth Depth
| Tat [Lene | temp [one | ME |W] yoca[ eg | one | HES OME] pai | nay
fathoms | fathoms fathoms
\

I 62° 30’ 8° ar’. 132 7°2 24 63° 06’ | 56° 00’ 1199 2°4 45 61° 32’ 9° 43' 643 4°17

2 63° o4' Q°:22’ 262 | 5% 25 63° 30’ | 54° 25’ 582 30% 46 619 32": |; 31° 36" 720 2°40

3 63° 35° | 10° 24’ 272 0°5 63° 51' | 53°03’ 136 47 61° 32’ | 13° 40' 950 | 3°23
4 64°07’ | 11° 12” 237 2°5 26 63° 57’ | 52°41’ 34 0°6 48 61° 32’ 15° 11’ 1150 Bah
5 64° 40’ | 12° 09’ 155 64° 37’ | 54° 24’ 109 49 62°07" | 15° 07’- |) 1120" | 2°91
6 63° 43’ | 14°34’ go 7°0 27 64° 54’ | 55° 10' | 393 3°8 50 62° 43’ | 15°07'.| Yo20 | 3°13
7 63° 13’ | 15° 41’ 600 4°5 28 65° 14’ | 55° 42 420 | 3°5 51 64° 15’ | 14° 22’ 68 7°32
8 63° 56’ | 24° 40’ 136 6°0 29 65° 34’ | 54°31" 68 0°2 52 63° 57’ 14739" 420 7°87
9 64° 18’ 27° 00 295 5°8 30 66° 50’ | 54° 28’ 22 1°05 53 63° 15’ 15° 07’ 795 3°08
10 64° 24’ | 28° 50’ 788 3°5 31 66° 35’ | 55° 54’ 88 1°6 54 63° 08’ | 15° 40’ 691 3°9
II 64° 34’ | 31° 12’ 1300 1°6 32 66° Bart KAgOn se. 318 3°9 55 Ce a, Al a dal 7 316 5°9
12 64° 38’ 32° 37’ 1040 0°3 33 67° 57’ | 55° 30" 35 | 0°8 56 64° 00’ | 15° 09’ 68 7°57
13 64° 47' | 34° 33’ 622 3°0 34 65°17’ | 54°17’ 55 57 63° 37’ | 13°02’ 350 | 3°4
14 64° 45’ | 35°05’ 176 | 4% 35 65° 16’ | 55°05’ 362 3°6 58 64° 25’ | 12° 09’ 211 0°8
15 66° 18’ | 25° 59’ 330 0°75 36 61° 50’ | 56° 21’ 1435 1°95 59 65° 00’ | 11° 16 310 |—o°r
16 65° 43' | 26° 58’ 250 6°r 37 60°17’ | 54°05’ | 1715 1°4 60 65° 09’ | 12° 27’ 124 | 0%9
17 62° 49’ | 26°55’ 745 3°4 38 59°12) | 51° 05" 1870 at 61 65° 03' | 13° 06’ 55 0°4
18 61° 44’ | 30° 29' 1135 3°0 39 62° 00’ | 22° 38’ 865 2°9 62 63° 78°") 16? 72" 72 7°92
19 60° 29’ | 34°14’ 1566 2°4 40 62° 00° | 21° 36’ 845 go 63 62° 4o’ | 19° 05’ 800 4°o
20 58° 20’ | 40° 48’ 1695 rs 41 61° 39’ | 17°10 1245 2°0 64 62° 06’ | 19° 00’ | IO4I 3°%
2I 58° or’ | 44° 45’ 1330 2°4 42 61° qr’ | 10°17’ 625 0°4 65 61° 33’ | 19° 00’ 1089 3°0
22 58° 10’ | 48° 25’ 1845 1°4 43 61° 42’ | 10° 11’ 645 0°05 66 61° 33’ | 20° 43’ 1128 3°3
23 60° 43’ | 56° 00’ Piankin Net ; 44 61° 42’ | 9° 36’ 545 | 4°8 67 61° 30’ | 22° 30° 975 | 3°0

Depth Depth
ee af eat eg We Loe Tink : sen ee eee ete Aoi ;
fathoms fathoms

68 62° 06’ | 22° 30’ 843 3°4 92 64° 44' | 32°52’ 976 1% 118 68° 27’ 8° 20’ 1060 | —1°o
69 62° 40’ | 22°17’ 589 3°9 93 64° 24’ | 35° 14' 767 1°46 119 67° 53’ | 10° 19’ Io1o | —1°o
70 63° 09’ | 22° 05' 134 7°0 94 64° 56’ | 36° 19’ 204 4°r 120 67° 29’ | 11° 32’ 885 | —1°o
71 63° 46’ | 22° 03' 46 65° 31’ | 30° 45’ 213 121 66° 59’ | 13°11’ 529 | —0°7
72 63° 12’ | 23°04’ 197 6°7 95 65° 14' | 30°39 752 2°r 122 66° 42’ | 14° 44’ 115 1°8.
73 62° 58’ | 23° 28’ 486 5°5 96 65° 24’ |. 29° 00’ 735 199 123 66° 52’ | 15° 40° 145 2°0
74 | 62°17' | 24° 36 695 4°2 97 | 65°28’ | 27° 39’ 450 5°5 124 | 67°40" | 15°40’ | 495 | —0%6

rl 67 175.35), 761 98 65° 38’ | 26° 27’ 138 5°9 125 68° 08’ | 16° 02’ 729 | —o°8

61° 28’ | 25° 06’ 829 99 66° 13’ | 25°53’ 187 6°r 126 67% 19" IS e Se: 293 | —0°5
75 61° 28’ | 26° 25’ 780 4°3 Too 66° 23’ | 14°02’ 59 0°4 127 66° 33’ 20° 05’ 44 5°6
76 60° 50’ | 26° 50° 806 4°r 101 66° 23’ 12° 05’ 537 —0°7 128 66° 50’ | 20° 02’ 194 0°6
17 60° 10’ | 26° 59’ 951 3°6 102 66° 23 10° 26’ 750 | —o°9 129 66° 35’ | 23°47’ 117 6°5
78 | 60° 37’ | 27°52’ 799 4°5 103 | 66°23’ | 8°52’ 579. | —0°6 130 | 63°00’ | 20° 4o' 338 6°55
79 | 60°52’ | 28°58’ 653 4°4 104 | 66°23’ | 7° 25' 957% | 19x 131 | 63°00 | 19° 09’ 698 4°7
80 61° 02’ | 29° 32’ 935 4°0 105 65° 34’ a? ax’ 762 | —o°8 132 63° 00’ | 17°04’ 747 4°6
81 61° 44’ | 27°00’ 485 6° 106 65° 34’ 8° 54’ 447 —0°6 133 63° 14’ | 11° 24’ 230 2°2
82 61° 55’ | 27° 28’ 824 4°r 65° 29’ 8° 4o’ 466 134 62° 34’ | 10° 26’ 299 4°1
83 62° 25’ | 28°30’ gi2 3°5 107 65° 33’ | 10° 28’ 492 | —0°%3 135 62° 48’ 9° 48’ 270 0°4

62° 36’ | 26° or’ 472 108 65° 30’ | 12°00’ 97 1° 136 63° o1’ 9° 11’ 256 4°8

62° 36’ | 25° 30" 401 Tog | 6§° 29’ | 13°25’ 38 1°5 137. | 63°14’ | 8°3r’ 297 | —0°6
84 62° 58’ | 25° 24’ 633 4°8 IIo 66° 44’ | 11° 33’ 781 | —0°8 138 63° 26’ 7° 56’ 471 | —-0°6
85 63° 21’ 25° 21' 170 Ill 67° 14’ 8° 48’ 860 | —o°g 139 637 36’ a9" 702 —o°%6
86 65° 03'6 | 23° 47'6 76 112 67° 57’ 6° 44' 1267 | —1°1 140 63° 20’ 6257" 780 | —o°9
87 65° 02’, | 23° 56’2 110 113 69° 31’ 7° 06’ 1309 | —1°0 141 63° 22’ 6° 58’ 679 | —0%6
88 64° 58’ | 24° 25’ 76 6°9 114 70° 36 7° 29' a | 18d 142 | 63°07’ | 7°05’ 587 | —0°6
89 64° 45’ | 27° 20° 310 8°4 115 70° 50" 8° 20’ 86 oP! 143 62° 58’ 7° 09’ 388 | —o0%4
go. 64° 45’ | 29° 06’ 568 4°4 116 70° 05’ 8° 26’ 371 | —0°4 144 62° 49’ 79 12" 276 1°6
gl 64° 44’ 31° 00’ 1236 at 117 69° 13’ 8° 23 1003. | —1°0

oe SB

THE DANISH INGOLF-EXPEDITION.

HITHERTO PUBLISHED:

1899. Vol. I, Part I. SS Reno of the Voyage = C.F. Wandel (1 plate) re | Kis ae eo Sh. Pe
2. Hydrography by Alartin Knudsen (34 plates)........ j

1900. — Part II. 3. The deposits of the sea-bottom by O. B. Boeggild
: (7 charts) Pe enw Me sae eae DS | i ip Sale - 800 (-. 11)
4. Current-bottles by C. #.Wandel (1 plate)............
1899. Vol. Il, Part I. The ichthyological results by Chr. Liithen (4 plates) ...

1899. — Part Il. On the Appendices genitales (Claspers) in the Greenland-

Shark, Somniosus microcephalus (Bl. Schn.), and other Sela- 5 SRO eet

chians by Hector F. L./ungersen (6 plates)..... ... Se Sa ali:
1900. — Part Il. Nudibranchiate Gasteropoda by R. Bergh (5 plates). foo - 4,75 ( - 7)
1904. —_ Part IV. The North-European and Greenland Lycodine by

_ Adolf Severin Jensen (10 plates)... 6.660.666 eee cece ees a caper (oe aa

1912. — Part V. Lamellibranchiata, Part I, by Ad. S. Jensen. .(4 plates

and’ 's Ho ttes sirthe Text) aso Gk set Ge es se india Gus es he ey - 800 (- 11)
1899. Vol. II, Part I. Pycnogonide by Fr. Meinert (S.platesy re. seiko - 600(- 9)
1908. — Part II. Crustacea Malacostraca, I: Decapoda, Euphausiacea, |

Mysidacea by- H. J. Hansen (5 plates) .......-.. 22 eee eee ees - 800 (- In) .
1913. — Part III. Crustacea Malacostraca, II: Tanaidacea by H./. Hansen ;

(ta "plates SOR iu hws Cae OME Na he cree ore ts. Lak Ss - 13,00 (+~ 18) |
1903. Vol. IV, Part I. Echinoidea, Part I, by Zz. Mortensen (21 plates) ...... - 20,00 ( sy 24)
1907. — Part II. Echinoidea, Part II, by 7%. Mortensen (19 plates)..... - 19,00 ( - 23)
1904. Vol. V, Part I. Pennatulida by Hector F. E. Jungersen (3 plates)....... - 650(- 9)
1912. — Part Il. Ctenophora by Zh. Mortensen (10 plates and 15 figures

TABS het) oe Ren Ricca oe Eee a amen ad fs hor, Gon 5 oa - 10,50 (- 14)
1912. — Part Ill, Ceriantharia by Oskar Carlgren (5 plates and 16 figures

TED CE LORE oo 2 Pe CRY alias ea anette geet ede - 6,0 '& 9)
1902. Vol. VI, Part I. Porifera (Part 1), Homorrhaphide and Heterotthaphidee

by Will. Lundbeck (19 plates).....-. 00.000. 0s cere cee ect - 17,00 ( - 22)
1905. —_ Part II. Porifera (Part 2), Desmacidonidze (Pars) by Will. Lundbeck

(20 SPACES send AS ne eay Pees aan WR teks ae Vig - 20,50 (- 25).
1gI0. — Part III. Porifera (Part 3), Desmacidomidze (Pars) By} Will. Lundbeck ‘ :

(11 plates) Rivers Seat ao Ras iS Pe eM eee A, - 1200 (- 16)

SN

es
ey

Se oe VOLE RART 4
cae 2 -DONTENTS:.
ae ; CARL WITH: COPEPODA, IL
: PUBLISHED AT THE COST OF THE GOVERNMENT
5 BY r
THE DIRECTION OF THE ZOOLOGICAL MUSEUM OF THE UNIVERSITY. :
* : ‘ °
: “QAM O/>-- >
Bo5 : COPENHAGEN. ‘ i 4 Ov FE \
ae, > : - : ; H. HAGERUP. Co aes }
Sas PRINTED BY BIANCO LUNO.
; 1915.

THE DANISH INGOLF-EXPEDITION.

VOLUME III.

4.

COPEPODA I

CALANOIDA AMPHASCANDRIA.

BY

CARL WITH.

WITH 8 PLATES, 422 TEXTFIGURES, 1 CHART AND A LIST OF THE STATIONS.

COPENHAGEN.

PRINTED BY BIANCO LUNO.

IQI5.

ae

eee ear
See eee fut Be

Bh bs I

CONTENTS

Copepoda I.

Calanoida Amphascandria.

Page

CEES Gol «101 he CE a a eS a I
On the material....... AEE SEU Pea gy Barer pa tee I
MENEZES E250 a Oe eR ee a 3
On systematic characters. . iy gee 2 Oe wre aie ae 4
Oe PontlarvAl development 37 5 )i sei eee ved cats een 7
On nomenclature and abbreviations ................. 7
On the description of species ..............-.-0...4.. 8
ROM BTIALION ANG PATEBILES ious ss ws Wes eee yg se yer ee es 9
NMR sai aie se oi aise eoaTs Sis vseaie oe ah a RES Be sty AC
SE arME ATIVE ROT 062) isis lc lesack omvisieibje ass WA 8 egos ds II

eee Grist Be RH Se ar ce Sa kk acces Ir

a Calanue firimarchicus: Gui os eal tees 10

A Bede CCR EMILOME Pe) Solel ie o's lenin as en bi eine eke es 30
PN OCIUITIB Gr SI OES Ye liicly cs ties. foreleg 4 iy cbig este vie 36

3. Macrocalanus princeps Brady..................... 37
RC MPRRINDOA IW ORs Gein sia! bia nado < oe laieinain ied sina 40

4. Megacalanus princeps Wolf....................... 41
DE EY SES 2s Seeley BAe cae Cra ea 44
5. Rhincalanus nasutus Giesbr. ..................... 44

6. Eucalanus elongatus Dana....................... 48

7 _ attenuatus Dana...............-...0-- 52

8. — fe Eo 0) SA sea a are pe en 53
POSMPAMIERE CONN pies GON MeL EA ior Se ciga wes oS ees a 54
OR BTACHIATHIG ae UES MIAN oo ieee. soi s Gesrs occ iy is 54
em OCHIATINORG O24 855 crake o pun Win hia WL AW a ea Alyys: @hs) 5 2's 57
10. Pseudocalanus minutus Kr. .................205.5. 57
11. Microcalanus pygmzus G.OSars................. 66
12. Clausocalanus arcuiformis Dana.................. 68
13. Spinocalanus abyssalis Giesbr..................... 69
14. _ MAGNUS WO ees ciicwiec esac nese. ue 72
ACOA ee oe eee Le NUE TE See oo ua oa 72
a6: Actidius armatiw: Boeeks sets ee. eo 75
16; Chisidins: armatus Boeck sos 5 ck ke sass cae es 77
17. — MABUENS: TS veers Lak Ove Wal wise 81
18. at modestus n.sp.....:... eA ey eee 82
19. — obtusiivons: GiO. Sars eo eh Sirs eee
20. _— gracilis’ Fame oo tyns tae ericl sce oes 85
21. Aetidiopsis rostrata G.O. Sars ........... ..ee.eu 86

22, Udinopsis-armatus: Vanl. 223.55 Ge va es a ena 88

Page

23. Gaidius tenuispinus G. O. Sars................... 89
24. =e brevispinns G.'O, Sate sei... us csee ves ots 94
25: Gaetanus Jetuppr GiesDre. i. cick ce eee ea bees s 97
26. — MOM ERANY Fst lacs vn edeny ie EUS has eae 103
27. = PCO LGR Mame cL Oi. s emis vais rede soo es 104
28. — DUCA ICMOS DRA To SP aic ey nce aie mae 107
29. —_— TateOne Gs: OC), CALA ei ee ices vsyepisios te 108
30. _ nb ELLE: | URE a (POR OI Da ea OPS tO III
31.. Euchirella rostrata Claus. ...............-..00055 113
32. — curticauda Giesbr. ..... Ril eas arom od 118
33- = messinensis, Claus. 20,005.60. 2. eeee.. 122
34. — POPINEA A NSPS his ad an 2, Wetter Dak
35. “= RINGS AMAOs ALONG. ook crag bev sv ec cag 127
36. — MTU DBE ois oie SOLE was actly Coca es 131
37. Undeucheete minor Giesbr................... Sis Sie be
38. — CATE ORR EST easy oa er eg 136
39. _ SUED MS BTN id saya enlaces 6d pid a. wie bs Oye 137
4o. Chirudina Streetsi Giesbr........................ I4I
41. _ Pustsuera GeOr Sars so ss as 145
42. — APEBMATIR TEND a0 2.5 giles icin Gag Sales ae 147
43. — noracantia \G. O: Sate... ek es 148
44. _ parviepura Fartatt . oor. tase cee cuss 151
Waldiviella Stemetre. oo5 Se ee 154
45. Valdiviella insignis Farran................ Sea 154
Eucheetidae ..... PL RL a aS eRe De ae 157
ACR UPENSEIE xo g 0 8%, ae pis aid ee wes we ewicc vege opie 157
46. Eucheete norvegica Boeck...........0.....0-0005 158
47. _- S6nsa) Giesbe ss Yonge oe e has Saat 166
48. — inwintidk PIANGON 5 dees hese 169
49. — MRSA OES ost eae pees onda a kai 172
50. — erodte BLaay oo 2 ie Per ws eee eee eee 174
5I. — WHIH MASTAR Cue PSS es OME Ss alee 177
52. -- REGS | AL OUM ES orn oes 3a burs eve a 179
53. — REAMONIS HOP ices! Soastu eat pain Seals aN 181
54. -- RG YE Ms Bp eo soos fies cards woe awe 182
55. — pimntata-G, O; Sate hoo aos eee ss 183
56. — gpetilis: GO; Sate Ss: Saaleas pn ees 185
57. — AGUA: GIORDK sc. e ace tes cokes ees oe aes 187
58. — HES. Slee his archi a oa ae ees 188

Scolecttiricidae:. sic cance hae et aes ERS 189
59. Scaphocalanus magnus Th. Scott ..........-..... 189
60. — brevicornis G. O. Sars ............ 192
61. — obtusifrons G. O. Sars ............ 194
62. _ VENOUS Parran 50 sare neues 198
63. _ globiceps \Parran (3) 005 ase 199
64. -- robustrus Th: Scott.oco5 2 202
65. Scolecithricella minor Brady .................... 204
66. — Ingolfi n. aps Veo seas eee 207
67. ovata Farran......... ltestes PEGS 208
68. Lophothrix frontalis Giesbr...................... 211
69. Scottocalanus Thorii-nisp. 20.25 5 i005. 0. oes ees 215
70. _ securifrons Th. Scott .............. 220

Phatonidaé.io5 3 feiss kaos esses ae ee
71. Cornucalanus chelifer Thomps. ..................
72. Onchocalanus magnus Wolf. ....................
re — erintntis SWolt ss ysl aa
74. _ hirtipes NS.30. Sarg. 5303 os sso
75. — Sifts ORs ais) Gabon es ah ace Cee
76. Xanthocalanus Greeni Farran ...................
77- — pitiguis Parren: |.) Gite eee
78. -- clayiger' Th. Scott#.S.an os bcs
79. _ hirtipes: Van.’ 2.232355 vce
80... Phatnna spinifera Claus, .4:.05555. rcs eon

List of Literature...... Basa be spase sip LE EIS SE

Explanation :of -the plates 5005. cies snd Sateen ees cee

Introduction.

My studies on the Plancton-Copepods, brought home by the Danish Ingolf Expedition, which
were commenced about 1904, have been delayed for several reasons, of which the three principal ones
are: in the first place that I for several years was occupied with other topics, in the second place that the
rich collections of The Thor Expedition from the waters around Iceland as well as those of the Danish
Expedition to East Greenland 1900 have greatly added to the work to be done; the third reason is,
that it was my intention to give so full an account of each species as possible, not only of the adult

males and females but also of the different stages of Copepodites.

On the Material.
The principal source of material was that of the “Ingolf” 1894 and 1895; the investigation of

this expedition “extended over the eastern part of the seas along the west coast of Greenland from a
point a little north of the polar circle to about 58° L. N., two degrees south of Cape Farewell, from
there in a north-easterly direction towards Iceland, the waters round this island and between Iceland
and the Feeroes, lastly eastwards to a line drawn almost due north from the Feroes to Jan Mayen”.
The above quotation is from Hansen’s Crustacea Malacostraca I of the Ingolf-Expedition vol. III 2
1908, to the introductory remarks of which paper I partly refer. The southern limitation in the
Atlantic was about 60° L,. N.

Comparatively few specimens were taken with the trawl; a good many of the samples were
gathered with ordinary vertical nets (P and V) in a depth iying between 50—300 fathoms and the sur-
face and a few ones with a closing net in considerable depth; numerous samples were- taken at the
surface with net marked Pl, Apst and Cyl during the voyage. The Ingolf collections give a very
good picture of the plankton copepods, the big as well as the small species, but only down to a depth
of 300 fathoms; the deeper layers of these regions are, as shown by the Thor, populated by numerous
species, which were not taken by the Ingolf, at least as far as the Atlantic South and west of Iceland
is concerned. It is a pity that no deep hauls were made on the West Coast of Greenland; an Atlantic
fauna, identical with that mentioned, should certainly be found here. It is rather interesting that in one
of the few samples, taken with a closing net at a considerable depth near Jan Mayen St. 118 a new
species Luchete Bradyi was found and in another a single specimen of so scarce a species as Scapho-
calanus brevicornis G. O. Sars was secured.

The Ingolf’s material from the Atlantic, rich in specimens, of the bigger as well as the smaller

species, which inhabit the intermediate as well as the upper layers, is in a useful way supplemented
The Ingolf-l-xpedition. III, 4. I

COPEPODA

lo

by the material gathered by the investigation-Steamer »Thor«<, the leader of which was Dr. J.
Schmidt, in the year 1903—1905. The region investigated by the Thor is the eastern part of
Denmark Strait, the Atlantic South of Iceland, the Iceland-Feroe Channel, a few Stations North-
east of Iceland and outside the Ingolf area, the Atlantic, South West of the Feroes. The hauls of
the Thor were made with the young-fish trawl from the surface down to a depth of nearly a thousand
meters (length of the wire out about 1800 meters.)

As the meshes of the young-fish trawl were rather wide, and as I have only examined few
of the surface samples, the Thor material gives a rather onesided picture of the fauna of pelagic
Copepods from these tracts. Several of the Copepods from the Thor were by Dr. Ove Paulsen sent
to Professor G. O. Sars for determination; to the former of these gentlemen I am indebted because he
kindly lent me these specimens, to the latter, one of the first anthourities on the Copepods, for
much useful information. ;

The third Danish Expedition to East Greenland under the leadership of the captain in the
navy Amdrup and with the late mag. sc. Soren Jensen as zoologist in the year 1900 has gathered
numerous samples during the journey. Surface samples were gathered each hour, day and night, from
19/5—?5/6 in the western part of the Norwegian Sea from 60° L. N. 3° L. E. to near Jan Mayen; from
27/s—%/, during the Journey from Jan Mayen to near the East Coast of Greenland (at about 92° Tas ty
ar° L. W.) in water, which often contained Scattered Ice. During the journey home from 3°/g to 3°/,
samples were taken generally each second hour of the day in the ocean North-West of Iceland, in
Denmark Strait and in the Atlantic South of Iceland as far South and East as 59°. Lo Ne
o. 52 L. W.

These surface samples (marked A, B, C, but generally F) as a rule only contain comparatively
few specimens and species, but they give nevertheless a very good impression of the diurnal variations
in the-occurrence of the most common species Cal, finmarchicus at least at the surface. The
meutioned Expedition has at Jan Mayen as well as near the Coast of Kast-Greenland taken some
vertical hauls with the closing net at moderate depth.

In addition to these I have:examined a few samples from East Grecia collected by cand.
E. Bay and Dr. H. Deichmann. ;

Our museum contains a good many samples containing Plancton-Copepods, from the week
Coast of Greenland; collected by Bergendal and W. Lundbeck, as well as from the waters around
Iceland, brought home by mag, sc. R. Horring, A. Ditlevsen, W. Lundbeck and Lieutenant in
the navy E. Jensen, 5

To discuss the number of species, which has been found in each of the explored regions by
the different Expeditions as well as other questions concerning the distribution of the species, will
more naturally fall within the next volume of this, paper, which will deal with the Calanoida
heterarthrandria; in the next volume I hope to be able to publish a list, showing.the number of
species and the proportionate number of the specimens of each successive stage occurring at
each Station. eR 8 coe

At present I am only going to say a few words about the number of species brought
home by each Expedition, I have altogether examined 79 species, which probably belong to the region;

COPEPODA 3

among these 13 were new to science. The Ingolf has only collected 2: species of which 3 were new,
the Thor has collected 69 different species (8 however outside the area explored by the Ingolf), of which
II were new, and the Danish East Greenland Expedition 1900 has only taken 13 different species, of
which only one has not been recorded previously. Of the Calanidae and related families the Ingolf
has taken 7 species, the Thor 9 and the @.Exp. 1900 5, of the Aetididae the three expeditions have
taken 6, 29 and 3 species respectively, of the Zuchetidae the Ingolf has taken 4, the Thor 12 and the
@.Exp. 3 species and of the Scolecithricidae the three expeditions have taken 4, 19 and 2 species
respectively. Of species, which by previous authors were recorded from the examined region, only a

single one Udinopsis armata Vanh. was not taken by any of the expeditions.')

On the Literature.

Without underestimating the fine papers by E. Canu and Th. Scott, it must be admitted,
that Giesbrecht and G. O. Sars are the two modern zoologists, who have contributed most to the
knowledge of the Plancton-Copepods. The work of the former indicates a new epoch in the studies
of these animals; unfortunately the arrangement of the topics in his main paper is so unpractical,
that it is often very difficult a to derive full advantage from the vast amount of information, which is
found in it. Giesbrecht has sometimes been blamed for giving unneccessarily many details for
the definition and understanding of the species. I do not share this opinion, as it sometimes occurred
to me, that details necessary for the limitation of two nearly related species were wanting in his
description. G.O.Sars has in many ways contributed greatly to the study of the Copepods as well
as to that of the other Crustacea; his descriptions are lucid and supported by numerous practically
arranged figures, but might sometimes be a little more exhaustive.

In the last ten years numerous Plancton-Copepods have been described from the deeper layers
of the North-East Atlantic as well as from other ocean tracts; the three principal authors, who have
described these species are Farran, Wolfenden and A. Scott. The papers of the first of these
naturalists have a direct bearing upon the Ingolf-Investigations; he has given good descriptions of
numerous new species and most useful information about the Copepod-fauna of the Atlantic Slope
of Ireland. Wolfenden’s papers often include a number of useful characters and details, supported
by beautiful drawings, but he does not always seem to have accepted the classic rules of nomenclature.
A. Scott’s main-paper on the Copepods of the Siboga Expedition, which only partly falls within
my sphere, contains most useful lists of synonymy, descriptions of numerous new species and several
"new characters; his descriptions are according to my opinion often a little too meagre for the definition
of nearly related species.

When speaking of the studies on the Plankton-Copepods of later years, I think a few words
may be added about a most useful paper by Koefoed & Damas on the collections brought home
by the duc d'Orléans, It may perhaps be allowed to set forth a few words of criticism. It is a
pity that the authors have not wished under each species to give a full acount of the biological facts,

1) Wolfenden (1904 p. 112) has from the cold area of the Faeroe Channel mentioned four species viz: Bradyidius
armatus Gbt., Udinopsis bradyi G. O. Sars, Bryaxis brevicornis Farr., Ctenocalanus vanus Gbt. and Scolecthrix similis Gbt., but as
they are all found south of the 60° L. N, I have not included them in this paper. The same is the case with Oothrix
bidentata Farr. which according to the duc d'Orléans was secured at 75° I. N. 14° L. W., somewhat north of the area, inclu-
ded in this paper. ;

y*

6 COPEPODA

In front of the labrum a sometimes hairy protuberance is found; this was by Sars in Euchete
designated the efzstoma; I have in this paper followed him, where the organ belonged to the somite
of the antennae. The /adrum proper, which is placed in the mandibular somite is often subdivided
and has in the Zuchetidae and Scolecithricidae its free or anterior surface more or less hairy, in a
way that often is of systematic importance (cf. pl. VI fig. 2b, 7a, 14a and pl. VII fig. 5e, 9b and
7c); along the hinder margin of the labrum, separating the anterior and the oral surface, marginal
bristles are always observed (pl. II fig. 3b; pl. IV fig. 5¢). The oval surface is adorned with a more
or less developed chitinous framework, to which longitudinal muscles are fastened; this system is by
comparison with fig. 7 f. pl. II and fig. 2a and 5e pl. IV seen to be differently developed in the different
forms. Along the median line three central circular spots, in the middle with two parallel lines, as well
as a fourth more posterior one, with a lateral one on each side are found; laterally a few spots, which
may perhaps be regarded as muscular spots, are observed (cf. pl. IV fig. 5e). About the nature of
these four central circular striated spots I do not know anything; they are certainly not muscular
spots, perhaps sensory ones. Around or behind the fourth spot a bigger or smaller transverse row
or area of spines or bristles is observed; the systematic importance may be realised by comparing
fig. 2a and 5e pl. IV. The oral surface of the labrum is on each side near the middle adorned with
a lateral longitudinal series of bristles or spines, which is again dissolved into five groups, the more
detailed variations of which show interesting differences between species and genera, as seen in
numerous figures (pl. I—VII). ;

The /abiwm is gradually fused with the postérior wall of the pharynx; it is generally adorned
with curious structures. In the middle a compactness in the chitinous skeleton the »/amina labialis« is
found; in front it is not well separated from the wall of the pharynx, but its hinder margin seems to
be partly free, and shows many variations, as seen by comparing the figures (pl. II fig. 7{, 2a and
3c; pl. Il fig. 5e; pl. V fig. 26; pl. VI fig. 3b, 1x b and 13b); in the Scolectthricidae this organ seems
to be wanting or poorly developed (pl. VII fig. 4e and 7 d).

Laterally to the /amina labialis on each side a longitudinal row of 6 generally well articulated
spines is found. I have designated it the serruda sexdentata, and as it was found in all the examined
genera except Candacia and Heterorhabdus within the Calanoida, but not in any of the few genera
of other groups, which were examined, it is certainly of some systematic importance. In front of the
lamina labialis and the serrula, curved longitudinal rows of bristles or granules are found, which as
seen in the figures show specific as well as generic differences (pl. I fig. 1¢; pl. Il fig. 2a; pl. II
fig. 5e; pl. IV fig. 1c, 2c and 3d; pl. V fig. 2b and 4c; pl. VI fig. 1b, 2d, 3b, 5a and rob and
pl. VII fig. 2c, 4e and 12¢c),. Behind the /amina labialis, more or less well developed areas, covered
with granules or spines are found (pl. II fig. 7£). The /adial lobes as well as the area between and
behind are covered with series of delicate hairs; the arrangement of these series is different in the
various genera, but these differences are probably modifications only of a general system (cf pl. II
fig. 7f; pl. IV fig. 1d, 4c and 5g; pl. V fig. 1c and 5f; pl. VI fig. 5b). Behind the area labialis in
the maxillular and maxillar somites an intricated system of hairy areas is sometimes found, f. inst. in
Calanus hyperboreus (pl. I fig. 1d).

In the literature I have found a good descpription of these organs in Laophonte and Hersiliodes

COPEPODA 7

(Canu 1892), but their structute is quite different from the one described; lately I have examined the
labrum and labium in two genera of the Harpactoida, in Oncaea and in Oithona, but only in the
latter genius found a structure not quite dissimilar to the one described.

'-\In the nauplius of Ca/anus I have not yet succeeded in elucidating the structure of these or-
gans; in the first postlarval stage of C. Anmarchicus the structure is in its main feature like that of
the adult one. i *

The structure of the mouth organs in the males is, in species in which the oral appendages
are not reduced, scarcely different from that of the female, but in other forms, it is more or less
‘reduced (cf. pl. IV fig. 1e; pl. VI fig. 3 e).

From the above it seems to me to be evident that the study of these organs in different forms

is of no mean importance.

On postlarval development.

Most modern authors, who have studied the Plancton-Copepods from the systematic point of view
have only paid attention to the adult males and females, even when younger specimens were present; in
later years Oberg has given a description of the larval stages in several species and Kraeeft has paid
much attention to the postlarval development in a very interesting paper; Damas, Paulsen and
Stephensen have for single species contributed to our knowledge of the development. It is generally
understood that Grobben is the first who has described the ‘nauplius in Calanus finmarchicus and
that Gran was the first to give an account of the postnauplial development; both statements are wrong,
as Kroyer, as early as the year 1847, followed the development of Calanus finmarchicus from the
nauplius to the adult (or more correctly the penultimate stage). In this paper I have not dealt with
the larval forms, but I have tried and generally succeeded in determining the postlarval stages;
I have named the first postlarval form stage I, and the adult male and female stage VI. About the
differences between the different stages in eacli species, and the reductions in the limbs. I refer to the
systematic part; the most complete account is found in the description of Cal. finmarchicus. The
mouth-organs are generally not reduced in the Stages IV—V; the, number ‘of setae in the exopodite
of the maxillulae forms an exception to this rule. In the adult female the number is 11, in stage
V it is 10, in stage IV it is 9, in stage III it is 8, in stage Il it is 7’ and in stage I probably 6.
The main differences between the stages is found in the number of natatory legs and number of
somites of the urosome.

Nomenclature,

In the naming of the different appendages I have followed Hansen as well as Giesbrecht,
who somewhat later arrived at the same result. Hansen has shown that the antennae, mandibulae
and maxillipeds really have threesegmented basipodites. The structure of the maxillulae in Valdtviella
mmsignis shows Clearly, that the basipodite of these limbs are threesegmented; the first basal segment
is adorned with the Lil; the second bears the Le and a single Li (II ~ III); the third basal segment
which is distinctly articulated to the preceding one, supports the tvo rami. The natatory legs ap-

8 COPEPODA

parently have only two basal segments; but according to Hansen the first basal segment of the
natatory legs is probably fused with the complicated chitinous system of the ventral surface; if this
is right, the first basal segment of the authors is really the second, and the second the third. In the
description I have followed this nomenclature; the last basal segment is accordingly designated the
third one (corresponding to the second one of most authors in the antennae, mandibulae, maxillulae,
maxillipeds and natatory legs); the second basal segment in my description corresponds to the first
one of most authors in the maxillipeds and natatory legs; the second basal segment of the mandibu-
lae and the first one of the antennae are as show by Hansen poorly developed.
About the different abbreviations used in this paper I refer to the following list.

Plancton nets used by the Ingolf. species are those used by Giesbrecht and

V_ signifies the big vertical plancton net. following authors.

errs the smaller one. Basp. I—III = The first, second and third base-
V2 — net with different width of the meshes. podite. ,
Pt — _. Apstein’s vertical net (Nr. 20). Ri — Ramus internus,

Re = Ramus externus.

Ri I—III and Re I-III signifies the number of
the segment of the endopodite or exopodite.

~ signifies that two segments are fused e. g.
Re II ~ III and segment 8&9 of the anten-

Apst. = A. The same net used in the surface.
Pl. — _ Surface plancton net.
Cyl. — Cylindric net.
Closing net is the net of von Petersen-Chun,
modified by Hensen.
Yt is the abbreviation of the youngfish trawl nulae.
used by the Thor: Si = an interior seta.
@. Exp. 1900 is the abbreviation of The Danish | Se = an exterior seta.
Expedition to East Greenland in the year 1900. | 5P = 4 posterior seta.
A. B.C. D. E. and F. are the different kinds of | Sa = an anterior seta.

surface nets used by this expedition. Spr = a proximal seta (antennulae).
f? = adult female. Sd = a distal seta (antennulae).

fg = fullgrown male. St = a terminal seta (Re III pes I—V).

Y = a young specimen. L, or Lob = lobe.
St. = the stage. Le or Li — Lobus externus or internus.

St. I—VI signifies the postlarval development;
St. I is the youngest first postlarval stage and
St. VI is the adult male or female.

The abbreviations used in the description of the

Sp = Spermatophores. Sp. within a bracket indi-
cates that specimens, bearing these structures,
were secured.

Sin. and dext. means sinister and dexter.

On the description of species.

As I have personally examined all the samples from the three expeditions myself and have picked
out a fairly big number of specimens, generally more than a hundred, if so many were present, adult
as well as young ones, I think that we get a fairly good impression of the proportion between the
different stages; Paulsen has as far as Calanus finmarchicus is concerned picked out a hundred
specimens to get an impression of the proportional distribution of the stages. In the systematic part
I have given an almost complete description of the species, which were only imperfectly described;
in cases, in which good descriptions have been given by previous authors, I have only added features,

overlooked, or differing from existing description. Not only the males and females of the last stages

COPEPODA 9

have been described, but also the younger stages, as far as they showed features of any interest. The
descriptions are as a rule rather long, partly on account of the new characters, which are taken into
account, partly because it often struck me, that existing descriptions were often too wanting in details
for a sure definition of nearly related species.

Under each species is found a list of synonymy, which I have tried to make as complete as
possibly for the years after the publication of Giesbrecht’s classical paper; for each species I have
given the measurements of each examined stage.

After the description is added a few words of the variations and parasites, if any have
‘been observed. Under occurrence I have only given my personal observations, but under distribution

I have dealt with the facts, previonsly published, relating to the occurrence of each species within
as well as outside the explored area. Under remarks the whole systematic position of the species

is discussed.

On variation and parasites.

In a good many species viz: Rhincalanus nasutus, Eucalanus elongatus, Paracalanus parvus,
Pseudocalanus minutus, Chiridius armatus, Gaetanus Kruppi, G. pileatus and G. latifrous, Euchirella
rostrata and curticauda, Euchete tonsa and barbata and Scaphocalanus magnus variations of different
kinds were observed; most common is variation in a rudementary fifth pair of legs and in the struc-
ture of the setae of the furcal branches; several of the variations are probably due to traumata and
regeneration, others certainly represent a kind of atavism. To study the whole question of variation
within the Copepods or to collect all the published facts (cf. Wolfenden and Steuer) does not lie
within the frame of this paper. But as such facts are rather scarce, and as they may be important
for a future student of these topics, it seems to me to be the duty of each observer to make his per-
sonal observations known, even if they are fragmentary. Negative statements are seldom of much
value; but nevertheless I think it rather curious, that abnormal segmentation, which is fairly common
in the Arachnids, Insects and Annelids, was never met with in any of the examined, I think several
thousand, Copepods; to my knowledge no case of abnormal segmentation has been observed in any

of the Crustacea.

In several species parasites of different kinds have been observed; I refer to the description
of Rhincalanus nasutus, Chiridius armatus, Gaidius tenutspinus and brevispinus, Gaetanus Kruppi,

pileatus and latifrons, Undeuchete superba and Chirudina notacantha.

The Ingolf-Expedition. III. 4. 2

1765.

1842—1845.

1849.

1863.
1886,
1892,
1892.
1897.

1898. .
1898.

1899. ?
1899.
1g00.

1900,
IgOl.
1902.
1902.
1903.

1903.

Fam. I.

1. Calanus finmarchicus Gunnerus.

Monoculus finmarchicus n.sp. Gunnerus, pp. 175,

fig. 20—23.
Calanus spitsbergensis n. sp. Kroyer, pl. 41, figs.
Ia—n.

Calanus affinus n, sp. Kroyer, pl. 41, fig. 5.

Calanus quinqueannulatus n.sp. Kroyer, pl. 41, fig. 3. |

Calanus spitsbergensis Kr, Kroyer, pp. 531—542,

*P- 552+
Calanus affinis Kr. Kroyer, pp. 544—545, p. 553-

Calanus quinqueannulatus Kr. Kroyer, pp. 545—
546, Pp: 553--

Cetochilus helgolandicus n. sp, Claus, p. 171, pl.
; XXVI, figs. 2—9.

Calanus finmarchicus Gunn. H. J. Hansen, pp.
255—256.

Calanus finmarchicus Gunn. Canu, p. 170, pl. I;
figs. 13—I9.

Calanus finmarchicus Gunn. Giesbrecht, p. 89, taf. _

6-8.
Vanhéffen, p. 278, pl. 1
fig. 7.
Aurivillius, pp.67—69.
Giesbrecht - Schmeil,
pp. 14—15.
— _ — Brady, p. 32.
T. Scott, p. go.
— Wheeler, pp. 164—
165, fig. 1.
G. O. Sars, p. 2.
T. Scott, p. 338.
Gran, pp. 56—65.
Mrazek, pp. 503—519,
figs. I—4.
Jensen, Johansen &Le-
vinsen, p. 303, tab. I.
G. O. Sars, pp. 9—11,
pl. I—III.

Calanidae.

1903.
1903. -

1903.
1904.
1905.
1905.

1905.
1905.

(Textfigs 1—5).

Calanus finmarchicus Gunn. I. C. Thompson, p. 15.
Calanus helgolandicus Claus. G. O, Sars, pp. 11 —12,
pl. IV.
Thompson & Scott,
p. 241.
Calanus finmarchicus Gunn. Wolfenden, pp. 126—
t 127.
G. O. Sars, p. I.
G. O. Sars, p. I.
Th. Scott, pp. 221.
Calanus finmarchicus Gunn. Farran, p. 30.
Damas, pp. I—23.
Esterly, pp. 125-—126;
fig. 1.
Calanus septentrionalis Goodsir. Norman & Scott,
p- 126.

— helgolandicus Claus. Pearson, pp. 4—5.
— finmarchicus Gunn. Paulsen, pp. 1—2I.
Williams, pp. 639—

640.
Damas & Koefoed, pp.
382—93; 405.
v. Bremen, pp. 7--8;
fig. 1.
— helgolandicus Claus. v. Bremen, pp. 8—9;
fig. 2.
Farran, p. 20.
Steuer, p. 21.
Sharpe, pp. 409—410.
Farran, pp. 83— 89.
Esterly, pp. 140—151.
Esterly, pp. 282—295.
Stephensen, pp. 308
—3I0.
Stephensen, p. 71.

— helgolandicus Claus.

— finmarchicus Gunn.

COPEPODA II

Giesbrecht refers this species to Monoculus finmarchicus Gunnerus, (p. 32—33). Kroyer

(1848 p. 528) has already shown that Gunnerus species was a Calanus, but he thinks that the
decsription is too incomplete for a sure indentification. In contrast to Giesbrecht I think that it
is quite impossible to tell if the species belongs to Cal. finmarchicus or to young specimens of Calanus
hyperboreus. The one figure in natural size: shows a small animal (c. 2 mm. long) even less robust
than most specimens of C. Anmarchicus; this figure and the author’s remarks about »quite small
animals« certainly speaks against its identification with Cal. hyperboreus, but the remark about, the
very pellucid, shining colour without indication of the reddish tint which is most often found in Cad.
_‘finmarchicus, especially the antennulae, does not bear out the same opinion. The biological conditions
under which the two species are found in the polar region, are almost identical, and do not allow
any conclusion. But as the name Cal. Jinmarchicus has been once recognized, and as it cannot with
better, probably with smaller, right be applied to Cal. hyperboreus, I think it right to follow Giesbrecht.
In other respects as far as the synonymy is concerned I refer to Giesbrecht; as I have however

As I have had the opportunity of examining Kroyers original specimens of Cal. carimatus and cristatus, 1 think that
a few words of their systematic position would not be superfluous, even if these species belong to another geographical region.

Calanus carinatus Kroyer.
1849. Calanus carinatus n, sp. Kroyer, p. 554.

1856. — brevicornis n. sp. Lubbock p. 11.
1860. —_—" — Lbk. Lubbock, p..117.
1892. _ — Lbk. Giesbrecht, p. 90; taf. 6, 7, 8.

Of this species Kroyer has examined a single not very well preserved adult female from the coast of Brazil. In
spite of the differences enumerated below I think it is identical with the midatlantic species, which Giesbrecht has referred
to C. brevicornis Lubk.. The total lenght was 2°0-++ 06=-26 mm. The marginal frontal keel is more prominent than figured
by Giesbrecht (t. 6, fig. 7) and the rostral spines are more stiff,’ but the lateral outline of the labrum shows the same
characteristic structure as figured by Giesbrecht. The fourth abdominal somite is dorsally 1:2 as long as the fifth one as
shown in Giesbrecht’s fig. 18, but in contrast to his text, in which he writes that the fifth somite is a little longer than
the fourth. - . ' wa :

2 The antennulae extend a little beyond the tip of the fourth abdominal somite; the segment VIII—IX are less
well separated than the rest. The distal. setae of segm. VIII and XII are not spinelike. The measurements are at least
different from Giesbrecht’s figure of the male (taf. 8 fig. 5); the segment 24 is alittle shorter than the 23, which is
scarcely as long as the 22. The 25 segment is rather mutilated, but seems scarcely to be half as long as the preceding one.

No marginal setae were found along the inner margin of the second basipodite of the pes II, IV and V, and no teeth.
The first Se of the Re III divides the outer margin in equal parts in the second pair of legs but in the fourth pair the
portion, proximal to Se 1 is 1°7 (not 1-4 as in drevicornis) as long as that distal to it.

Calanus cristatus Kroyer.
1845. Calanus cristatus n. sp. Kroyer, pl. 41, figs. 6a—k.

1849. — cristatus Kr. Kroyer, pp. 546—550, p. 553.
1884... — a Kr. Poppe, pp. 282—286; taf. XX, fig. 1-6.
1892, -— _ Kr. Giesbrecht, p. 91, t. 6, figs. 14—15.

Of this species I have examined 14 young specimens (Kroyers original ones), of which 12 belonged to pernultimate
stage and a single to stage IV. They were all rather mutilated, but nevertheless it is scarcely doubtful that Poppe’s and
Giesbrecht’s rather imperfect descriptions refer to this species. Total length is 8°6 (7-0 -+1°6). Shape of the head is alike
Giesbrecht (fig. 14—15); the lateral corners are rounded and not produced. The antennulae extend with the 25 segment
beyond the end of the abdomen. The segment 8g are only indistinctly separated and together just as long as the segment
21, which is 115 as.long as.the segment 22. The latter is 1°r as long as the 23 and 25 segment, which is 1.3 as long as
the 24. The mouth-appandages scarcely provide features of interest. The Ri of pes I—IV possess no Si The RelIII pes II
is by the SeI divided into a proximal shorter and a distal almost 1:2 as long; the exopodites of the three last pair of legs
are wanting. The inner margin of the first basipodite of the fifth pair of legs is smooth.

2*

12 COPEPODA

had the opportunity of examining Kroyer’s original specimens of this species, I do not find it out
of place to add a few remarks.

Kroyer’s description and figure of Cal. Spitsbergensis apply without doubt to the mature
females; his description is clear and remarkably exhaustive; he has seen and described the receptacula
seminis; his original specimen is a Cal. finmarchicus. Kroyer’s description and figure of Cal
affinity applies to young specimens (St. V), but of his 3 original specimens the two belong to the
fourth stage. The description and figure of Cal guimgueannulatus refer without doubt to the male
of Cal. finmarchicus; Kroyer’s original specimens were not preserved, but a number of specimens,
determined by Kroyer as C. guinmgueannulatus, were males of Cal. finmarchicus.

As Kroyer had unfortunately not examined mature specimens of Cal. hyperboreus, but only
young animals, he was obliged to establish his species on specimens of stage V; accordingly he did
not realise that the number of abdominal somites is not a systematic character, and was not able to
understand the full cyclus of development from nauplius to fullgrown animal of Calanus finmarchicus
ow hyperboreus. He realised that is was too difficult for him to distinguish the earlier stages of these
two nearly related species. Starting from the stage V of Cal. hyperboreus he regarded the stage IV
as the oldest larve; he has given fairly good figures and clear descriptions of stage I—IV; he has
recognised the nauplius and metanauplius as forming part of this cyclus. I think that Kroyer was
the first to set forth the almost complete development of one of the Calanoid; so full a description of
several features does not seem to have been published for this species in spite of its importance (cf.
Damas p. 8, who thinks that Gran is the first to recognise the larval stages).

As I have been obliged to examine a big number of specimens of this species from the wide
area investigated by the Ingolf, the Thor and the East-Greenland Expedition, I have felt it necessary
to try to solve the question whether Sars is right or wrong in establishing the two species Calanus
finmarchicus and C. helgolandicus'). According to Sars:

The female of the more southern form C. helgolandicus is about 3 mm. long, the male 2°8 mm.,
while C. finmarchicus is 4 and 36 mm. respectively; the former species is more narrow in form with
more angularly produced head. The urosome is in Cal. finmarchicus about half the length of the
metasome, and the caudal rami are-somewhat longer than the anal somite, while Cal. helgolandicus
has the urosome exceeding half the length of the metasome and the caudal rami scarcely longer than
the anal segment. In Cal. helgolandicus the antennulae extend only 2 segments beyond the caudal
rami but 3 in Cal finmarchicus. The most important difference is found in the fifth pair of legs of
the male, which are more asymmetrical in Cad. helgolandicus with the Ri sin. extending a little beyond
the Re 1 (not beyond the middle of Re II) and with the Re III scarcely exceeding half the length of
the Re II (not nearly so long).

The difference in size does not, as suggested by Sars, always correspond to a more northern or
southern distribution as pointed out by several authors. Mrazek (p. 502) has in the same samples from
Spitzbergen found mature females varying in size from 34 to 52 mm., Damas and Koefoed have
from the same locality seen specimens varying from 32 to 54 mm. (cf. p. 382). Giesbrecht’s spec-

1) A name, which Norman & Scott with good reason propose to replace with Cal. septentrionalis Goodsir.

COPEPODA 13

imens varied from 2°7 to 4.5 mm. I have found the same to be the case in several samples from the
west coast of Greenland.

In a sample from Jakobshayn I found roo specimens (ff) varying in size from 3°3, 3'5, 38 to
41 and 4 specimens 46 to 53 mm. long; a young female from the same sample measured 3°9 mm.,
Ig young ones measured about 3 mm. From Ingolf St. 28 f? of size from 3°5 to 5:1 and young spec-
imens from 3'5 to 4°8 were taken.

By comparing the length of the urosome and anterior portion in specimens from different
localities and of different size etc. it was quite impossible for me to find any character of value. In

“specimens of £2 from the west coast of Jutland (Thyboron, Thor *7/, 04) the head was certainly more
produced than in specimens taken 73° L. N. 8° L. E. by Johannes Petersen, but in the former
the caudal rami were scarcely as long as wide, and a little longer than the anal somite, and in the
latter distinctly 2:1 as long as wide. In 3 of the mentioned specimens from Denmark the antennulae
reached three segments beyond the tip of the urosome, but in 2 other specimens two only; in specimens
from Spitzbergen (c. 3°4 mm) they extended three segments beyond the end of the urosome, but in a
big specimen from Greenland (5:3 mm) with the head even less produced than the specimens from
Spitzbergen the antennulae extended only two segments beyond the urosome.

As far as the shape of the head is concerned the differences between the different types are
better marked in the males than in the females; as far as the characters found in the fifth pair of
legs are concerned I first tried like Mrazek to find a character in the variations of the spinulation
of the inner margin of the second basipodite, but like him without success.

In Sars’ figures of C. finmarchicus the pes V does not extend to the end of the abdomen;
in none of my specimens the pes V is so short as figured by Sars; in all my specimens they extend
to or almost to the end of the abdomen. In all the examined males (from Denmark, Greenland or Spitz-
bergen) except in a single one from Denmark, the Ri III sin. reached beyond the middle or almost
to the end of ReII. In a single specimen from Denmark the Re II sin. was 17 as long as the
Re III, but in most other specimens the Re II was 1-4 or 1'5 as long as Re III; the last segment
differs from Sars’ figures by a more or less marked rounded protuberance basally and inwards.

Scott (1905), followed by Pearson (p. 5), has accepted Sars’ two species, but most authors
agree in regarding the proposed characters as insufficient f, inst. Wolfenden (1904 pp. 126—127),
Farran (1905 p. 30) and Gough (1905). Mrazek has (1902 pp. 502—506) without knowledge of
Sars’ point of view tried to solve the question. Without result he tried to find characters in the
dentation of the inner margin of the first basipodite of the fifth pair of legs. He writes p. 504:
»Etwas konstanter erwiesen sich die Langenverhaltnisse der vorderen Antenne. Die Lange derselben
ist der Lange des K6rpers umgekehrt proportionell,.«< He. also found differences of some value in the
armature of the legs, and the relation between the length of the different parts of the body; but he
rightly thought, that a detailed study of a larger material, consisting of specimens, originating from
a different region of the ocean with statistical methods of studying the limit of variation, would scarcely
solve the question, without at the same time studying material from well defined geographic regions.
The question ought soon to be properly investigated, for if Cad. finmarchicus and helgolandicus should
really be proved to belong to two different species, a good deal of the vast amount of knowledge

14 COPEPODA

about the biology and distribution, collected in the last years, is in danger of losing considerably in
value. All questions regarding development, propagation and distribution should in most regions be
extremely, difficult to investigate, if’ we instead of a single well defined. species had two very
badly limited.

Description f¢—?. Size: {9. 2:8—55 mm. fig. 3—44 mm. (Smallest specimens Feeroe Iceland
Channel; largest Davis Strait). i

The number of secretory pores scarcely differed in the males and females, or in specimens
from different localities.. In the first pair of legs no secretory pores were found; on the anterior sur-
face of Ril, at the base of Se, sometimes a minute pore (?) was seen. In pes II—V a minute pore
was found on the anterior surface at the base of'a minute Se of third basipodite; in the Re I—II a
more or less distinct pore was found at the base of Se in the four last pair of legs, and a distinct one
was found at the base of the Se 2—3 Re Il} but in addition to these in the pes III—IV a pore was
found corresponding to the missing Ser Re III, in pes II this pore was most often wanting. The
shape of the labrum etc. (cf. textfig. 6) is somewhat different from Sars’ fig. (pl. I). Between the
insertion of the antennulae a small elevation is found, which by a transverse groove, less prominent
than shown in the figure, is divided into a shorter anterior portion (a) and a longer posterior one (b).
Separated from this by a narrow groove and between the insertion of the antennae a low elevation
(c), slightly convex from before backwards and from side to side is seen. In front limited by a trans-
verse groove, behind by the free posterior margin and laterally gradually continued into the transverse
chitinous bar, situated between the articular cavity of the antennae and mandibulae respectively, the
labrum proper is found. The mentioned chitinous bar is medially to the articular cavity of the
mandibulae connected with the area labialis, thus forming the chitinous bed, in which the manduca-
tory portion is situated (cf. Sars’ fig. pl. II). The /aérwm proper has in front, in the middle, a prominent
tumulus, beset with a number of long bristles directed backwards. On each side of the process an
oblique series, directed outwards and backwards, sometimes fused with the lateral marginal row, is found;
it consists of short spinelike hairs. In front of hinder margin on each side a group of fairly long setae,
beginning in’ the middle and directed backwards and outwards, is Suan ys: and laterally. a marginal
row of rather short spinelike hairs is found.

The oral surface of the labrum shows an arrangement alike that of Cal ioviaaloniae (pl. I fig.
1b), but the enlarged group in front is less developed (differing on the two sides in the two examined
specimens), the first group is converging anteriorly, the second group is medioconvex, well separated
from the first group, but only indistinctly from the third one; the third to the fourth groups are partly
fused and consist of several rows of hairs. Transversély between the last series only a few teeth
are found.

The lamina labialis (textfig. 1), which seems to form a part of a transverse yechitinous system,
has antibelacle a median tooth, and on each side two or three teeth (often assymmetrical). In front
of the lamina labialis a delicate granulation is found in the middle between ‘a median series of shorter
and a lateral of longer hairs. Behind the lamina and between the serrulae 6dentatae an outer group
of fairly delicate hairs and a median one of thick granules, fused with a group between the labial lobes

COPEPODA 15

are found. The arrangement of hairs on the labial lobes and the somites behind seems, as far as made
out, to be like that of Cal. hyperboreus. In several specimens it was seen that the transverse line, which
limits the maxillar somite posteriorly, is continued just in front of the articular cavity of the maxilli-
pes and laterally into the membrane, dorsally and posteriorly limiting the head. Accordingly the
first, thoracic somite bear two pair of limbs viz. maxillipeds and pes I, and thus corresponds to two
somites (cf. Hansen 1893).

By examining females from Denmark I did not find any difference from those described except
in the arrangement of the hairs of the ventral surface of the maxillar and maxillular somite, which
‘is less complex than those figured.

The only difference between males and females seems to be the more prominent median

process of the labrum in the former sex.

Textfigure 1. : i Textfigure 2.

Calanus finmarchicus G. 9. Labial lobe seen from : C. finmarchicus G. 9. (Stage IV—V).
in front with lamina labialis and serrula 6den- , a. Pes-V sin. (stage V) in anterior view X 85.
tata etc. < c. 170. : b. Pes IV sin. (stage IV) in anterior view X< 85.

c. Pes V sin. (stage IV) in anterior view < 85.

Y. (St. V). Size: Varying from 22 (Egedesminde, Davis Strait), 2°5 (73 L. N.. 8 L. FE.) — 48
mm. (Davis Strait). Gran’s specimens (+ urosome) varied from 21—26 and the specimens from duc
d@Orléans 3—4'5 mm. '

This stage, in which I have not been able to distinguish males and females, is easily disting-
uished by 4 abdominal somites of which the second is the longest, 2-7 as long as the first and 1-4
as long as the anal somite. The mouth-appendages are scarcely different except the maxillulae,
which have only 10 instead of 11 setae in the exopodite. The four pair of natatory legs are scarcely
different from those of the mature female, but pes V differs by fused Ri II—III without indication of
Se II but with the number of Si7 as usual, and by the fused Re II—III with 5 Si and well
developed Se Re II (textfig. 2 a). Number of secretory pores seem to. be alike f? in pes II—IIJ, but

16 COPEPODA

in pes IV no secretory pore corresponding to Se 1 Re III was seen and in Re II ~ III pes V only
a single pore is found at the base of Se 3.
The labrum shows in lateral view complete similarity to Sars’ figure pl. I but has the anterior

process less prominent than in most f-9 examined by me.

Y. (St. IV). Size: Varying from 2 (63° 43 L.N. o26L. E.), (18 + 06) = 24. (South West
of Iceland), 26 (Davis Strait), 28 mm. (64° 56 L. N. 36° 19 L. W.) to 29 mm. (Jan Mayen). Gran’s |
specimens (+ urosome) varied from 1:4—1'83 and specimens from du¢ @ Orléans from 2—35 mm,

This stage is easily distinguished by 3 abdominal somites, of which the third one is the
longest, being 1,3 as long as the second one, and 2% as long as the first one. The number of setae

in the furca is scarcely different. The antennulae (with 25 segments) and mouth-appendages (including

a b ¢ d e f

Textfigure 3. Cal. finmarchicus G. 9. (Stage III).
a. Head from the right. x 85. b. Abdomen from the left. « 85.
c. Pes II dext. Re in post. view. I10. d. Pes III sin. in anterior view. IIo.
e Pes IV sin. in anterior view. IIo. f. Pes V sin. in lateral view. I50.

the labrum, exteriorly as well as in oral view) except the Le of the maxillulae, which only possess
9 setae, are scarcely different from f. Pes I has the Ri II—III fused and an indistinct articular mem-
brane between RilI and II; the Re II—III are also fused but in other respects this appendage is
scarcely different. Pes II—III have the same segments fused, the Se RilII is missing, but Ri has 10
setae as usual; the Re II ~ III have only 5 Si. The pes IV differs from the preceding pair by 8 setae
only of Ri (textfig. 2b). The pes V is more clumsy than in stage V with undivided Ri with 6 setae
and undivided Re with 4 Si and 3 Se. The inner margin of basipodite II has 3 teeth (textfig. 2c).
Secretory pores are in pes II—IV wanting in Re III, corresponding to Se 1- 2, but found at Se Re II
and at Se 3 Re III; in pes V secretory pores are found at base of Se Re I and Se 3.

Y. (St. I). Size: Varying from 1-4 (Davis Strait), 17 (1°3 + 0-4) (63° L. N. 15° L. W.) — 2'4 mm.
(Davis Strait). Gran’s specimens (+ urosome) of his stage IV varied from 1o5—144 and specimens
from duc d Orléans 2—2:2 mm.

COPEPODA 17

The body appears more slender than in the preceding stage; the urosome consists of 2 somites;
the Se of furcal rami is missing (textfig. 3 a—b). The antennulae, which consist of 23 segments,
extend 3 segments beyond the tip of the abdomen. The antennae and other mouthlimbs except the
maxillulae, in which the Le has 8 setae and the Re 8, are scarcely different. The lateral outline of
the labrum is as shown in textfig. 3a alike stage V, but the frontal protuberance is less prominent.
The oral surfaces of the labrum and the labium are in their main structures alike f9.

Pes I= St. IV. Pes II in main features alike St. IV, but Ri with 8 setae and Re II~ III,
which is less slender, with 4 Si only (textfig. 3c). Pes III is comparatively shorter than II, and the
Re IIe III has only 2 Se (fig. 3d). The pes IV (fig. 3 e) has no seta in basipodite II, 7 setae in
unsegmented Ri and 3 Si-+ 3 rather short Se in Re. The pes V (fig. 3 f) is represented by a wide
indistinctly divided basal part, which is distally attenuated, and here subdivided into longer outer
branch with at least 3 setae decreasing outwards and a shorter inner branch with 2 fairly long setae.
Secretory pores were with certainty only observed at the base of Se 3 Re II~III in pes N—III.

Textfigure 4. Cal. finmarchicus G. 9." (Stage II).
a, In lateral view X 85. b. Pes IV X 225.

Y. (St. Il). Size: Varying from org (S. W. Iceland), 1° (Davis Strait), 1-3 (r + 0:3) (Jan Mayen)
— 16mm. (Jan Mayen). Gran’s specimens (+ urosome) of his stage V varied from o'78—1‘or and
specimens from duc d’Orléans from 14—18 mm.

The body is more slender than in the preceding stage (textfig. 4 a). The head is sometimes
indistinctly separated from the first thoracic tergite, in addition to which 3 somites are found, of which
the last one only bears a rudimentary pair of legs. The antennulae, which reach about one segment
beyond the tip of the furca, consist of 18 segments only, as the segments proximal to the 11 are more
or less fused. The antennae and mandibulae are practically alike those of the ff. The number of setae of
the maxillulae is comparatively small; Le has only 6 setae, Li I has only to spines, basipodite II
has 3, RiI 1, Rill 2, Ri lI 5 and Re 7 setae. The maxillae are in the main features alike the f9.
The maxillipeds are in shape alike the preceding stages, but the Basp. III has in the middle only

2 Si, as the basal one is wanting, Ril has a single seta, Ri II (probably Ri II ~ III) is rather elongate
The Ingolf-Expedition. III. 4. 3

18 COPEPODA

with a median and a distal Si and the following segments are fused with 4 setae. The labrum is
searcely different from the preceding stage. Pes I is in the main structured as in the two preceding
stages, but the Si of basp. II is very delicate, the Ri has a fairly well developed articular membrane
between the RiI and Ri II~III. The pes II is practically alike the pes III of the stage III, and
the pes III alike pes IV (cf. fig. 3 e). The pes IV is alike the pes V of stage III and the pes III
of stage I (textfig. 4 b).

Y. (St. I). Size: Varying from o'8, o'9 (0°77 +02) — rz mm. Specimens from duc d’Orléans
were I mm.

The head is more produced than in the following stage without distinct filaments; behind the
head 3 fairly distinct somites are seen in addition to the two somites of the urosome. The antennulae,
which scarcely reach the end of the urosome, consist of 11 segments only; proximally 3 indistinct
segments are found, the segments 11—18 are probably fused and the segments 19—25 are free. The

antennae and mandibulae are
practically as in ff. The ma-
xillulae are alike those of
preceding stage but the number
of setae seems to be somewhat
smaller. The maxillae are in
main as shown in textfig. 5 b
alike £9. The maxillipeds are
even more reduced than in
the preceding stage, as easily
recognised by studying fig.
5b. The Ri, which is only 2/; as
long as the basipodite III, con-

Textfigure 5. Cal. finmarchicus G. 9. (Stage I).

a. Lateral view of the labrum 225; . b. maxilla and maxillipes X 225; c. pesI sists of the long basal segment
(perhaps somewhat flattened by the pressure of the glasscover) X 225; 4d. pes II with two 2 Si and _ shorter
sin. in anterior view. X 175.

terminal segment with 4 setae.
The lateral outline of the labrum and labium are, as seen by comparing textfig. 5a with
3a, somewhat different from stage III, the longitudinal series of hairs on the oral surface are in
the main arranged as in the preceding stages, but the hairs are very short. The lamina labialis, the
longitudinal series of delicate hairs in front of it and the serrula sexdentata are scarcely different from
preceding stages. The pes I fig. 5c has 2 wide basal segments without Si. The undivided Ri has
7 setae and the Re has 3 Si and 3Se. The pes II (fig. 5d) is less slender but in other respects alike
pes IV stage III. The pes III is alike pes V stage III. No secretory pores were observed.
Occurrence etc. Calanus Jinmarchicus Gunn. was, as there was good reason to expect, found all
over the area explored by the different expeditions. As I have examined a great number of this
species from several hundred of samples, I thought it worth while to examine the proportion of the
different stages in each sample. As the number of specimens, which were originally picked out from

COPEPODA 19

the samples, were not selected from this point of view, and as the istruments, by which the different
hauls are made, are widely different, the results arrived at are only to be compared with caution, and
are not expected to give more than an impression. For getting an exact knowledge of the vertical
and seasonal distribution of a species like Calanus finmarchicus, we are obliged to have at our
disposal numerous samples taken with a closing net at the different hours of the day, and in the
succeeding months of the year at the same localities, scattered over a wide area. Most of the samples
at my disposal are surface ones; the vertical hauls are not procured with a closing net. Like most
expeditions in these regions the Ingolf Exp. etc. has only taken plankton samples in the months of
the summer (May to September) and seldom in different months in the same region.

West coast of Greenland. The Ingolf Expedition has in the months of June and July 1895
taken several samples with C. /nmarchicus.

June July
°
St. VI . . a
Number of samples in which each stage occurred N 7 2
in'17 samples June and in 15 samples July. IV 9 13
III 8 12
II 6 8
I 4 7

Table showing the proportion, in which the different stages were found.

Station Bath in Temp. ee of different stages. Numb ee oof
Date 1895. | L. N. | L. W.|| of athiciis Sur- | St. VI specimens
Ingolf. "| face. 3] Vj} iv | Ur | |} I | examined.
18/6 4 p.m. 60°29 | 34°14] St.19 | Vt 300-0} 9° C. | .. | 31] 64} 5° | .: ajar ease 100
26/6 2 p.m. ||63°30 | 54°25]| St. 25 | Vt 200—0 | 2°9° C. | .. | 17 |} 24 | 19 | 15 | 13] 12 || 200
2/6 3 p.m. || 63°56 5| 52°41) St. 26 | Vt 20—0 | 299° GC. .. I I 2 14 | 52 | 30 | 130
1/7 8 p.m. |65°r7 | 55°42]) St. 28 | Vt 100—0| 1°15°C".. I || 2r | 57 | 20 |... | 65
5/7 3°30 p.m. 65°34 | 54°31|| St. 29 | Vt 50-—o0 |3°5° Coz | 3 |] 32 | 22°3 | 2374] 18) 1 | 340
11/7 8°40 p. m.| 66°35 | 55°54] St.31 | Vt 50o—o | 26°C] .. | 03] 03] 18 | 36 | 45 | 04 | 230
6/, 11p.m. || Holstensborg.| .. Pig 5° C.|io5 | 2 H9t'5| 2 Re | ae oe ee | 100
18/7 3 p.m. 65°17 | 54°17] St. 34 | Vt r0o—o| 51°C. AA ES | 20%: 1°30) 3)"29") 2 | 50
28/7 7 p.m. ||61°50 | 56°21 || St. 19 | Vt 100—0| 8°5° C. 3 | 47 | 47 2 2 a ea 200
| |

The following table shows the number of the mentioned 9 samples, in which a certain per-
centage of the different stages were found.

Stage. VI Vv IV Ill II I
Percentage.

0°%o fo) fe) ° I 2 4
o—5 7 2 3 2 2 3
5—I10 o fe) fe) fe) fe) fo)
10—20 I I 3 3 2 I
20—50 I 4 2 % 2 °
50-75 ° ° I fe) I I
75— 100 te) I Q Q Q °

20 COPEPODA

From the above it is impossible to draw any conclusions except that all stages occur fairly
frequently in the months of July and June. As mature males have been found in four samples (in
addition to the 2 mentioned: */; St. 27. 64°54 L.N. 55°10 L. W. V" 200—0 and 2/6. St. 26. Pl. 25. 63°57
L.N. 52° L. W.), in the month of July it is safe to conclude that propagating takes place at that date.
From the North of Greenland Lundbeck and Bergendal have 1889 and 1890 (°/,—%/s) taken 7
samples, which all contained mature females. The other stages were less frequent. In the samples
from August and September the mature were found in comparatively few samples; in the two examined

samples, with numerous specimens, the stage IV formed the majority.

Lundbeck Bispatieiad | Bergéiidial Percentage of each stage. Nambener
Peal 6-26/3 1890 | Lundbeck. l specimens
7 Samples. 8 Samples. 8/g 14/o. VI| v | Iv | Illi 11| 1 | examined.
VI 7 3 Rs Lundbeck 6/6 go. 65°27 L. N. 53°48 L. W. 2%! 0 | 19 | 27 | 27 | 25 > 100
Vv 2 5 3 Lundbeck "4/, 1890 Diskobay. eg | | he (ae el etal ee > 100
TV) 4 7 Bergendal 6/, 1890 Diskobay. vie ARES BS) CBRE a “5 > 100
Tit} ‘2 7 be Pong
IL 2 5 tye eke er
I 3 I | PN A ne

Mature males were taken by Lundbeck 19/; 89 (57°08 L. N. 49° L. W.); females with sperma-
tophores *3/; 89 (59°12 L. N. 52°05 L. W.). In addition to these localities, males were taken by Soren
Hansen "/, 85 (59° L. N. 51°18 L. W.), and males are mentioned under the name of C. gucngueannulatus
by Kroyer from Greenland.

Denmark Strait. The Ingolf Expedition has 22/;—"/, 1895 and 25/s—*8/6 1896 taken 28 samples
containing C. finmarchicus. The different stages were distributed in the following way.

6 | : $ 4% |Percentage of each stage. Oa veg Number of Samples.
yf A F Depth in | 3 S 3 8/38 Ey re
Stage. < Ey Date. Ingolf. Z DP | Sethi ae VI ag 5 8 @ VI
ag ei 3 O° V jIVjIIl 11} I ae 5 Fw — 1; V JIViIII 11; 1
Z a8 /[a|9 Zo | ase || 9 |
oak
| "
S| 2 |6t/.p.m. . a
VI Q| 24 |//s 1895 St. 9 | 64°18 | 27°10 | Vt 100—017'9° CG] 2 | 28]} 7 | 13 | 23| 23] 4 || c. 200 fo) Bhs | ety ache heed 9@
Vv 18 }}21/; 1895 | St.11 | 64°34 | 31°12 | Vt 200—0|7'0° Cl] x | 70} 16] 6 | 4} 1] 2] 175 oe fa fe ota rail ae
IV 19 Ae hn St. 16 | 65°28 | 27°05 | Plt rr 8° C.].. | 1271/48) 20/ 4 ].. 7o|| 11—20|...)..} | 1} 2
III 18 Nhe 63°43 | 24°20| Cyl. 10 PaO Ta byes eles 86] 20—so|..{1}2}1] 1] 1
II 9 2By6 1896 St. 96 | 65°24 | 29°00 | P. r100—0 |7°9° Ci} .. j1.5 || 39] 58 j1.5|-. | .. 64] 50—75 |..| 1/]..| 2
I 5 75—100

The S/S Thor has from '2°/, 1904 taken 14 samples containing Cad. finmarchicus with the
young-fish trawl from deep water, in addition to several from the surface, which have been examined
by Paulsen (cf. 1906 p. 10).

COPEPODA ai

The East-Greenland Expedition 1900 has in the Denmark Strait from */,—22/, between 65°
Lat. North and 62°45 Lat. North, and between 35 and 26° Long. W. taken 50 samples (F. 312—366),
of which 30 contained C. /; the hauls were made each second hour day and night at the surface.

re) F Percentage of each stage.| ‘6 E bi = Number of Samples.
—_ “\ 5 eu b=!
Stage. Z Ei 1904. — L. N.| L. W.|| Depth in metres. | yy 24 39 g VI
a V |IViIIL 11) I ERs 5 as Keates: Yo PSE ae]. E
Z 3/9 AZ| hen | o|9
3 9 19/6 | St. 152| 65°00 | 28°10 || Yt. 200 M. Wire 6.5] 57/36/0.5|.. | .. | .. || 130 fe) I Sen ihy®
fe) VE 14 || 2/6 | St. 153] 65°20 | 27°12|| Yt. 800 M. Wire |}11|60/27| 2]..]..|..]| too] o—5 | 3 i}°2
Vv 10 || 2/6 | St. 154| 65°27 | 27°10 || Yt. 15 M. Wire CP POFN GS pet pen 1.5] .. C2304 B—1O } 2 I
IV 4 : Ag Pee 4 ee POS Ves Pas disc] ssf 1OO | II—20.| F I
: Yt. 80 4178) 18)'..}) 2.) [2.9 17§ || 20—50 3
ie ae sale .. | Yt. 800 2 | 52/46 roo || 51—75 a ae
18/6 | St. 149] 65°52 | 26°12 || Yt. 250 2/58] 40 80 || 76—100 3 |

From the following list it seems to be fairly safe to conclude that the C. f in the month of
September is more common at night than in the day time at the surface, and that the stage IV—V is
the most common. In no sample I have examined more than 30—40 specimens; in the few ones
containing that number the percentage of the stage IV—V was greatest. Only a single fullgrown

female was found in a day sample.

Number of
samples in The time at which samples | Number of | Number of
St which spec- were taken by the Danish samples samples
48¢-| imens ofeach East-Greenland Expedition without | containin
P g
stage were 1900 from 8/9—22/, Oh Cf:
found. .
VI 8 Taken between 4°05 morning 18 8
Vv 25 and 7°55 evening
IV 23 Taken between 8 evening 3 de
Ill 13 and 4 morning
Il 7
I 7 =

For drawing any conclusion from the material from the Ingolf and the Thor Exp. at the
present time the material is too scanty. But it can not be denied that the percentage of mature spec-
imens is bigger in the August-June samples, and that propagating takes place about the month of
June, as fullgrown males or females with spermatophores were found *°/, 1892 (Lundbeck Dyrefjord),
c. 7°/; 1895 and 7°/s 1904; no males were found September 1900.

South of Iceland. In the Atlantic south of Iceland from about 28° Long. W. to the Feroe-
Channel, and as far South as 60° Lat. North, the Ingolf Exp. has '/;—"/, 1895—96 taken about 55
samples containing C./, and in August 1895—1896 about 10 samples.

22 COPEPODA
Percentage of each stage. ma Number of samples in
Depth Temp id id og which each stage was
Date. |Ingolf. 1. N.|L.W.|in fathoms| _* VI Ze) Stages. found.
and net. | SU v |ivjim)m| 1 }é
face. | g | 9 12/,-16/6 August
4c ge | + [8t°30}27°25| Cy 25 | 88°C}. | 4 30|60| 6|.. |ro9] ;
VI
i 96 St. 83 | 62°25/28°30]| P. roo—o |} g'2° C. 10 | 13] 5] 22 | 50] 60 fe) } 25 6
ee oe St. 73 | 62°58)/23°28 || V. roo—o} 773° C. o5]} 6 | rr | 63 | 19 | 0°51 135 Vv 39 10
“hot ie Bs Whee Phir | 83°C 2| 38 | 48 | 12 217 IV 46 8
“9/6 96 | St. 74. | 62°17|24°36]/ Plr2 | 83°C. 4) 7 | 81 4 || 100 Ill 38 5
ith on St. 69 | 62°40|22°17 || V. 10oo—o ? 15 | 29 | 51 100 Il 30 6
Alot St. 67 | 61°32|22°29 Pl, 86° C 1|49]43|7 || 72 I 12 4
et fe % St. 62 | 63°18/19°12| Pl. ro =| 7°79 C 20 | 39 | 40] 1 136
a? i St. 63 | 62°40/19°05) V. 100 | 83°C 2] 31 | 33 | 34 100
3 p.m. . : - 3 ‘Sg Fi Number of samples.
116 96 St. 64 | 62°06)19°00/ A. 16 86° C. 9|49|34| 8 178 kee |
£3 | VI
3, Aes St. 54 | 63°08/15°40] Pl 5 |9° C 2) 2132] 9] 33 | 22 1233 re V jIv}|m4| | I
ae
19/5 96 | St. 55 | 63°33/15°02 || V. 1o0o—o0} 84° Ci! 1 28 | 21 | 27 | 21 | 2/100 a hi
bing 6 | 63°43|14° . 50— 68 =.
16/5 95 St. 3°43/14°34 || V. 50—0 ? 70 4| 533) 2 I ‘. wiofl3i:.{113
%fy 96 St. 53 | 63°15|15°07 || V. 1o0—0| 88° Cl ., 8 | 10 | 61 | 21 || 70] o—5 | 2 61a ick
he St. 49 | 62°07|15°08 | V. roo—o | 9°3° C. 29] 2| 7 | 16 | 25 | 21 || 77) 6-10 ry] 417)2)213
Wag St. 52 | 63°57/13°32|| V.200 | 83°C] 1| 8] 7 | 10 | 13 | 53| 8 |/t0o\11—20] 1] x | 2 | 2 | 4 | 3
bie 96 St. 57 | 63°37|13°02| V. 100 | 8:2° CC. 26 | 26 |} 2| 6/19 | 14] 7] SO}2I—5o) 1} 2173] 8)7|514
4p g6 (St57| -- | + | Att | 85°C] a3] 15] 32] 8 | 32 50} St—75 : 8 Bis
ie oe St. 133] 63°13/11°24 || P. r1oo—0 |10°8° Cl] 5| 88] 7 «+ [403 76-100} ., j x | 1 I |

The Thor Expedition has
September,

in 1904, south of Iceland, taken 1 sample in May, 5 in July and 2 in

IV

Ill I
Il I
I

The East Greenland Expedition 1900 has south of Iceland (62°—60° Lat. N., 21°—8° Long. W.)

62°49

Number of samples. Percentage of each stage. aa
x s/s Depth i se
Cy 1904. teat dae Na || Ly We Eee VI as
2 Thor. metres, £9
D | 24/5, | 2tt/7,| I-2/o, J ViIv| WI} WW] I ie
dls P t
St? 2 3 2 2/7 | St. 171 | 63°46 | 22°56 ? II | 52 | 37 70
Q| 1. 5 I u/, 183 | 61°30 | 17°08 /Yt.1800M.W.} 1 | 90] 9 500
Wet iis 285 18°46 Yt. 100M.W.) 2 | 89 100

,

from 23-28/, (F 367—430) taken 63 samples of which 22, contained C./, but only a few specimens, seldom

20 and only once 46.

COPEPODA 23

In addition to the localities mentioned, specimens in propagating have been found by Lundbeck
*8/, 1890 55°25 Lat. N. 29°05 Long. W. (5d; 259; 5(V); 15 (IV); 5 (111); 1 (11), "/, 1893 between Talkna
and Arnarfjord (1 fd; 8 2; 2 (III).

pase pom r§ The hours at which the Number of | Number of
Stage. ferent stages. samples were taken by the samples samples

405 a.m, | 8 p.m. Danish East-Greenland Exp. | without | containing
—7'59 p.m.| —4 a.m. 1900 23-#8/g C. f. C. f.

VI 7 7 Taken between 4'05 morning |, 29 *

Vv 7 7 and 7°59 evening.

IV, 4 5 Taken between 8 evening és we

Ill 4 and 4 morning.

II ms

I

By S/S Thor several males and (St. 183) once females with spermatophores were found in July,
and even '/, By the Ingolf Expedition it has been found propagating in several samples from May
1896 and °/s 1896 (Cyl. 12 62°17 Lat. N. 28°03 L. W)).

When the material collected in May —June is compared with that collected August and September,
one is struck by the fairly equal representation of the different stages in the spring, and by the pre-
ponderance of the stage V—VI in the August— September samples. When the difference between day and
night-samples is compared with that from Denmark Strait, it is seen to be less marked; in the number
of specimens of the different stages no marked difference was found day and night.

Iceland-Fzroe-Channel.. The Ingolf Exp. has South-East of Iceland in May 1895—96 taken 9
samples containing Ca// and in August 1896 7 samples.

oe of | Depth ‘Temp. Percentage of each stage. 3
Stage, |———, Date. Scat Me | de Wels iat." at — VI Se
Poa 96 188 R: | fathoms. | surf. | 5 | 9 V jiv| ur) mW) 1 3 2
1895—96| 1 : z
3 \ VI 4 1 {3/595 2%/ap.m.| St. 4|64°07|11°12||V.t100—o| .. 2 195 st WAP eca Weeks el er ed (einga|) Ceo.
Q II 5 12/5955 p.m. | St. 2|63°04| 9°22] V.30—0 | 95° C.|| 05 1795] 4 | 4] 2] 5] 5 || T00
Vv 8 7 11/5958 p.m. | St. 1| 62°30} 8°21|| V.t50—0 [10° Cr j25 || 18 | 20 | 24 | 12] 0 |/100
IV 5 7 || 0/5 969a.m. | St.59 | 65°00! 11°26], A. 12 353) Coe, GS Boat. op cabins BaOO
lll 5 4 10/§ 96 7 p. m. |St. 139) 63°36| 7°30]) A. 80 g° Ci .. | 2 | 20] 49 | 14 | 13 | 2 | 100
il 5 3 |/sg61op.m) .. |63°45| 7°25] A. 81 85° C.] .. | 4:5] 47 | 19 | 15 | 10 | 4°5]| 100
6 2°30—
I 3 3 pe ace 63°30| 7°40]} Cyl. go j10°5° C1 | 5 13

From the Thor expedition 1904 I have only examined specimens from 4 samples, 3 containing
males or eggs.

5/; 04. St. 63. 64°05 Lat. N. 0°38 Long. W. Yt. 300 M. Wire 7 £9 (2 with spermatoph.); 3 fd; 2 V.
9/; 04. St. 70. 63°35 Lat. N. 6°20 Long. W. Yt. 100 M. Wire 17°/,£4; 80°/,f2 (1£2 with sperm.); 3°/o V.
22/. Og. St. gg. 61°15 Lat. N. 9°35 Long. W. Yt. 100 M. Wire 90°/,f9 10°, V.

24 COPEPODA

My material from Ingolf and the few samples from Thor confirm Paulsen’s result. that the
propagating in this region takes place in the beginning of May. It is rather curious that a single male
was found in September. Compared to the May samples those from September show a preponderance
of Stage IV—V.

South-West of the Feroes. In the Atlantic, South-West of the Feeroes, about 8 samples with
C.f were taken 3°/,—?6/, 1905 by the Thor.

Stage.
Number hi Number
Stage. of 1905. | Thor.| lL. N.| L. W. Depth’ ie VI of spec-
samples. cee Vv imens.
fo} Q

Q 7 8/6 05 | St. 72 | 57°52 | 9°53 || Yt. 600 M. W. Sige oss 50
Vv 6 21/6 05 | St.9o0| 47°47 | 8°00 | Yt. 300 M.W. || 15 | 60 |. 25 75
IV I s re ie

In addition to the two mentioned localities a male was found (?4/5 49° L. N. 12° L. W.), and
females with spermatophores (3°/; 59°49 L. N. 8° L. W.). Propagation accordingly takes place as far
South as 47° Lat. North 2/6. In this connection ought to be mentioned that the S/S Thor (St. 223 B.
17/, 1904) at Thyboron, Denmark, has taken 50f9, 5 fd, 10 (V), I (IV); and that Rink *"/, 1858 has
taken 1 fd‘, 12 £9, 16(V), 5 (IV), x (III) at the Orkney Islands. ea

South-East of the Faroes. The Ingolf Expedition has South-East of the Feroes, as far South
and East as 57°53 L. N. 7°39 L. E. from 5-7/; 1895 and 4°/, 1896, taken 10 samples containing C. /,
and from '-'5/s 1895 and 19/3 1896 9 samples; they were almost all taken with Cy/ and contained
generally 10—30 specimens (cf. tabula).

Number of Number of samples!
containing each

samples stage taken by | The hours, at which samples | Samples
from G.E : Samples
Stage. - Xp. 1900. were taken by East-Greenland | without wc
nee. Night Day Exp. 1900 2939/9, Cf. wa

8p.m. | 4a.m.
May. Aug.) —4 a. m. | —8 p. m.

2 Taken between 4°05 morning

6 I ft +3 4
Vv 6 8 fe) 4 and 7°59 evening.
IV 7 6 2 Taken between 8 evening and 8 a
Ill 8 2 4 morning.
ae eo a
I ae I

In the May samples from the Ingolf the different stages seem to be equally well represented
in contrast to those from August, in which the stages IV—V are best represented. In this region the
Thor has in 1905 collected some fullgrown males viz: 1 fd, 2 (V) ("/, 1905 St. 120 59°54 Lat. N. 1°19
Long. E.), 1 £3, 2 (V) (7/7 1905 St. 119 59°54 Lat. N. 4°00 Long. E. Yt. 500 M. W.), 1 fo, 15 £9, 12 (V)
(lg 1905 57°33 Lat..N. 4°26 Long. E.).

The East Greenland Expedition 1900 has 29/,—3°/, (59°33 L. N. to 59° L. N.; 3°24 L. W. to 0°05

L. W.) (F: 431—453) collected 23 samples, of which only 4 day-samples contained a few specimens of
C.F. (cf. tab.).

COPEPODA 25

Norwegian Sea. The East Greenland Expedition has from 9/;—*4/, 1900 crossed the Norwegian
Sea from 60°26 Lat. North, 3°10 Long. East to 69°06 Lat. N. 6°12 Long. West. In the samples taken
with the net F. (F. r—89) 79 were found containing C._f but only 5 without any specimens. In addition
to these, 5 samples, taken with a closing net and 6 samples with net A and B were taken. The pro-
portion between the different stages in 39 samples from the whole region which were examined in
this respect was a follows.

vI 17
Vv
Iv a The number of samples

Il 14 stage occurred.

I 7

No males wére found at the surface in the explored region. As I have unfortunately not

Il ZL | (altogether 33) in which each

examined the proportion between the stages in all the 79 samples, and have not with security classified
the larval stages, the following remarks are set forth with due reservation. In the more southern part
of the region (to 64° N. F. 38) the stage IV—V were found in 14 samples of 16, the f? only in 4
(1—2 specimens) [F. 27: 10 (V), 6 (IV); F. 29: 8(V), 16 (IV)]. In a few samples (between 64° N.—65° N.)
the younger stages were well represented f. inst. [F. 51: 4(V), 20(IV), 20 (III), 18 (II), rz (1); F. 52:
2(V), 10 (IV), 14 (II), ro (II), 20 (1)].

In 10 samples taken between 67° L. N. and 69° Ll. N. (F. 62—81) f2 were found, in fairly big
numbers (5—10), but only in a single one of these (F. 64 6 £9; 2(V) 1 (IV)) stage IV—V were found and
in another stage I--II (F. 66 2 £2 5 (II), 15 (1); in the latter sample as well as in most of the ten
mentioned above and in several others often large numbers of eggs and larval stages of Calanus, certainly
of Cal. finmarchicus, as no Cal. hyperboreus was found in this region, were observed. It seems to be
probable that propagation took place in this region c. 4/5 1900, in a similar way, as Damas has
found out with a more southern and eastern region. Whether the propagation between 62—67° Lat. N.
has taken place at an earlier date, or if the juniores there found are born in the region explored by
Damas, it is at present impossible to tell.

Near Jan Mayen. In the ocean tract passed by the Danish East Greenland Expedition from
28/s II p. m. 1900 to 9/, 9 a. m. from near Jan Mayen to 74°15 Lat. North 12°21 Long. West (F. 91—
F, 243) about 145 samples were found, of which only 4 contained a few specimens of C. f viz. F. 92
8/6 I1 p.m., F. 96 3/5 4 a.m. and F. gt 8/6 11 p.m. with 5 £9, 2 (V), 1 (III) near Jan Mayen, and
F. 143 ?/, 8 a.m. 72°30 L. N. 0°41 L. W. 1 £9. In the samples F. 153—243, which were taken between
scattered ice or along the ice-edge no specimens of C. £ were observed, but 17 samples with a few
specimens of C. hyperboreus. A few vertical hauls in the region near Jan Mayen show that the fauna
of C. f in deeper waters was probably richer.

3 | o{/viiwimln
25/6 1900 Jan Mayen 50—60 f. || .. | 21 | 56| 14} 2
25/6 12 a, m. at the surface | 7 Sy i ba pee ate
12 p. m. ’ 5| 2 ss
28/6 ide keke ne
1/7 1 p.m. Closing net 1oo—5o f.) .. | I] 3 a
50—25 f. | 1 pa Bel eae pg I
4/7 300— o f. Et3 >

The Ingolf-Expedition. III. 4. 5 4

26 COPEPODA

It is worth noticing that a ff was found between 50—25 fathoms. In this connection it may
perhaps be of some interest that Johannes Petersen "/, 1901 73 Lat. N. 8° Long. E. caught a
big sample consisting almost exclusively of C_f: the proportion between the stages was the following:
FP 52 °%o3 V 42°5°%/o IV 3% IL 1% Il 05%) I 1%o

Jan Mayen to East Greenland. From 9/, 10 a.m. to 7/, 5 a.m. taken in the sea north-west
and west of Jan Mayen between 74°28 Lat. N. 15°03 Long. W. and the coast of East Greenland at
70°29 Lat. N. 21°21 Long. W. I have examined 13 samples (F. 244—262), of which only 5 contained
C.f. viz. St. VI in 3 samples, IV in 1, I, in 1, I in 1°

East Greenland. The East Greenland Exp. has, near the coast of Greenland, taken some samples
containing C.f in vertical hauls. viz.

VI |} Vj Ivj mW
10/, 6 a.m. 1900 72°28 Lat.N. 15°30 Long. W. Closing net 6—of | 3} 9| 2
6 a.m, 120— of. | 1 | 12
Closing net 110-40 f. | 10 | 6] 1
16/, 1900 _— 35—Io f. 8 | 18 se
29/, 1900 Stewards country Gurt 9
28/3 1900 Forblas Fjord a a: {A
28/, 1891 E. Bay. 72°26 Lat. N. 19°56 Long. W. 70 | 30

On the voyage home between Forblas Fjord,*Antarctic harbour, and 70° L. N. 18° L. W. from
3°/3 g p.m. to 2/, 9 a.m. 1900 the East Greenland Expedition collected 20 samples (F. 265—278), of
which 12 night samples contained C. / in different stages, while 4 day samples only contained a few
specimens (St. I—II]), and the remaining 4 nauplii only.

II

I
Nauplius| 12
Eggs 5

Stage. Spm. | 38. Date. @. Exp. Po: See ner: Naupl. jeggs.
4a.m. | 7p.m. sae vi |v | Iv |r| m| I | imens.
VI 2 30/3 10 p.m. | F. 266] Forblasfjord || 1°5| 9°5| 3 | 10 | 32 | 44 75 c c
Vv 2 II p.m. | F. 267 ai 3 |6 | rr | 49] 16'| 15 85 c e
IV 4 31/8 8 p.m. | F. 277 ate end kia tages AO tea: 26 50 c
Il 9
8
8

Taken between
3 a.m.—7 p.m. 4 4

Taken between
8 p.m. and 4 a.m. |

C0 MwWw:

The vertical hauls show that stages IV—V of C./ are fairly frequent in the month of July.
As no Cal. hyperboreus were found in any of the samples, and as the younger stages of Copepodites of
C.f. were common, there is every reason to regard the nauplii and eggs found in large numbers all
over the surface as belonging to the same species. Accordingly there is no reason to doubt that an
important locality for the propagation of C.f is sometimes found in this region. The few samples
and the small number in which the {2 were found suggest that the f?—¢ are either exstinguished
or living: in deeper strata,

COPEPODA 27

North of Iceland. The East Greenland Expedition has in the region crossed from 2/, 10 a.m.
to 4/, 10 p.m. between ca. 70° L. N. and 67° L. N. and between 17° L. W. and 23° L. W. taken 27
samples (F. 284—310), of which only 8 (taken in the night) contained C./ -

Number of Number of
samples at samples with
which each @. Exp. 1900. OR Date. Net. vi| vj iv|m| 1
stage was eo

found. + +

bbe a Taken between 17 a 3g XO: De iter.) H..209) ¢.689 Dh. N.. 279%, Wels | 4 [2 [ase l F

¥ 5 3 a,m.—7 p.m. |.

IV 4 10 p.m. | F, 300 ney Fu | DH EET

Ill 2

Taken between
- | 3 8 p. m—4 a. m. 4 8 4/9 2 a,m. | F, 301 ses Hopap | 2x
2

The contrast to the previous group is well marked by the preponderance og stage IV—V, and
by the fact that no nauplii were found (cf. p. 21 about their occurrence in Denmark Strait).

The Ingolf Exp. has from '8/,—3/s 1896 collected 9 samples with C.f/ north and east of Iceland
(as far south as c,65° north) and 17 from '—*5/, between Jan Mayen and north-east of Iceland (in-
cluding St. ror, 121 and 107).

[a a Paine Percentage of each stage. °
Stage. | samples | samples 1896, Ingolf.| I. N. L. W. Depth at VI oe
ae a at fathoms. v |Iv|u1) 1} 1 83
18/7 —3/8. | 10—25/,, surface, 319 Z 5.
o\ vr fe) I 2/g 96 Io p.m. eg 66°40 | 22°15 A. 73 aa Gaerne Wee, 1 30° | 4501.20 | 3. F 2 |] 75
fe} 4 12 1o/, 4°30 p.m. | St. 101} 66°23 | 12°05 || V2. 100—o | 5°5° C. || 2/20 | 9 | 20| 35 | 14! .. || 150
Vv 7 8 10/7 5 a.m. |St.102| 66°23 | 10°26 || V2, ro0o—o | 43°C. || .. (84 | 16 | .. | .. |e. |e. 50
IV 7 14 u/, 4:20 a.m. | St. 104 66°23 7°25 || P. 100—o | 63°C] ..-| 1 I 6 | 16 | 55 | 21 75
Ill 7 12 %/7 It a.m. |St.120| 67°29 | 11°32 || V2. ro0—o | 51°C, || ...| 0°5| 0°5) 20 | 49 | 28 | 2] 133
II 6 12 24/7 3°30 p.m. | St. 117) 69°13 8°23 || V2. 100—o | 41°C] .. | 20 | 75 3a rol ee al ieee | ie es

I 6 9 :

The S/S Thor has in 1904 taken two samples with C. f% viz. 72/, St. 214 67°19 L. N. 17°55 L. W.
Yt. 800 M. Wire 4 £9, 14(V), and 23/, 1904 St. 216 66°15 L. N. 12°13 L. W. Yt. 600 M. Wire 1(V). As a
f$ was taken '/, 1896 and by the East Greenland Expedition near Jan Mayen '/, 1900, and as Cope-
podites of stage I—II and nauplii of C. /? were taken at several stations, there is reason to think that
propagating takes place in this region in the month of July.

Distribution etc. About the distribution of Cad, Jinmarchicus 1 refer to the able account of
Farran (1911). It has “been recorded from the South Atlantic off Cape Colony, the west coast of
North and South America, the Mediterranean, the Adriatic, the Red Sea and the Polar Ocean.” In
the Pacific it has been found abundantly by Esterly in the Bay of California. ,In the North Atlantic
it is distributed over the whole of the area north of about 55° N.” It is sometimes found in great
numbers along the east-coast of North America and is, to the east, distributed as far as the western
part of the Baltic.

28 COPEPODA

To deal with the vast topic of its seasonal occurrence in the area investigated by the Inter-
national Commission does not fall within the scope of this paper, and has fortunately been as well
done by Farran as the in several tespects incomplete material allowed. As, however, the important
contributions to the biology of Calanus finmarchicus by Damas, Damas & Koefoed and especially
by Paulsen are based upon material from the regions investigated by the Ingolf Exped., and as all
the conclusions, to which these authors have arrived, do not quite stand criticism in details, I feel
obliged to deal rather exhaustively with these papers.

About the vertical distribution of the different stages it seems to be a general rule, that the
younger the stage of development the nearer the surface do the specimens live, as pointed out by
Damas, Paulsen and Farran; the fullgrown females and males are generally spawning on the
surface in every case in the northern seas, as set forth by Damas & Koefoed, who write (1907
p. 393) “La ponte de Calanus finmarchicus s’opére visiblement 4 une profondeur d’autant plus grande
que la région considérée est plus méridionale. Par la méme, la distance de la céte ot it se reproduit
augmente progressivement; autrement dit, cette espéce prend un caractére océanique de plus en plus
accentué.” About the vertical distribution of the C. f within the day I have only found observations
by Esterly, who writes (1911 pp. 140—151) as his conclusion:

1) C. f is most abundant at the surface about 7—8 p. m. during June and July.

2) It has begun to leave the surface by midnight and is most abundant at a depth of 5—10
fathoms about midnight.

3) The plurimum during the day (6 a.m.—6 p.m.) is probably 200 feet.

He thinks that the effect of light upon the “geotropisme of animals is probably the main factor
involved”. On a much bigger material (1912, pp. 282—95) he arrives at almost the same result.

Unfortunately he has not examined the part which the different stages play in these diurnal
migrations.

My material was not well adapted for solving this question, but the difference in the number
of specimens taken by the Danish East Greenland Expedition in Denmark Strait (?3-28/,) cf tab. p. 21,
from North-East Iceland (?-4/,), but especially from East Greenland (cf. tab. p. 26), indicate that all stages
inhabit the surface-layers in the night in some regions and at some seasons, in which only the
youngest Copepodites or the larves are frequent in the day.

It must accordingly be admitted that there is a source of error in comparing the relative
proportion of the different stages contained in surface samples, as Paulsen has possibly done, as he
does not state whether the hauls are made in the day or in the night.

It may perhaps be allowed to set forth one more general remark against Paulsens con-
clusions, that they are often based upon a too scanty material; even if, £ inst. five samples from a
certain region show almost the same proportion between the stages, it is not at all inprobable, that
the next 5 will show quite another result.

Paulsen thus summarises (1906 p. 7) his results based on the Thors material from April 1904.
“In April, there are many adult Calanus finmarchicus and Naupli at the surface of the sea to the south
of Iceland, many Nauplit (Sample 10) west of Iceland likewise on the surface. North of Iceland
there are but few adults and probably no jwnzores. Along the east coast of Iceland C. / seems for

COPEPODA 29

the most part to be absent.” On p. 6 “I thus venture to conclude that stage III [my IV] has been
predominant along the west coast of Iceland in April”. Only 2 samples (7 and 9) bear out this
opinion; sample 1 but especially 1o—12 (taken same date and locality with different nets}, when
rightly interpreted, shows the species in propagation. The conclusion, as far as the North is concerned,
is based on several hauls with negative result and 2 samples taken with young-fish trawl and with
C. 95 fo £2; to bear out this conclusion much more material is needed.

His conclusion for May reads. “Whereas the Atlantic and the waters between the Fxroes
and Iceland are rich in C. f£ the waters on the east and north coast of Iceland are poor, of the west
coast we know almost nothing.” The Ingolf material from May and June 1895—96 (cf. tab. pp. 20—22)
confirms this view, and shows the species in full propagation especially in the latter half of May. The
same is the case in the middle of Denmark Strait, Paulsen’s conclusion from north Iceland is placed
on far too scanty material. oe

Paulsen’s conclusion for June reads. “To the south and west of Iceland there are great
quantities, mainly sumzores, — west of Iceland considerable quantities of adult both #f and 9... On
the western part of the north coast of Iceland, where the water is warmer, many jumiores were also
found, on the eastern part, where the water is colder, few or none” (1906 p. 12). The Ingolf material
(cf. p. 22) from the south of Iceland confirms the conclusion that the juniores predominate; the great
number of St. I—-III probably indicates the new. generation. My own samples from the Thor and in a
less degree from the Ingolf (cf. p. 20) tell the same story as far as the west coast is concerned. Paulsen
thinks that the adult males and females probably belong to the new generation, “as they occur along
with a number of juniores, most of which are in the larger stages”. This proportion between the
stages, which f. inst. is not found in a sample (Ingolf St. 9 7°/;), seems just as much to speak for
referring them to the old as the new generation. The hauls from the north coast are so few, that it
must be admitted that our knowledge about the occurrence of C./ in the month of June is too
incomplete for any conclusion as far as this region is concerned.

The author writes (1906, p. 13). “Summarising the conditions in July we find that Calanus
Jinmarchicus has increased more in the south than in the north, and that individuals on the easterly
north coast are larger than those of the westerly north coast on the one side, and than those on the
east coast on the other.” The greatest number of specimens of the south coast belong to the stage
V—VI; Paulsen’s suggestion that deep hauls with the young-fish trawl would show a considerable
amount of males is shown to be right by tab. pag. 22; whether these specimens belong to the elder or the
new generation is impossible to tell. The two samples (Nr. 3—4) from the north western coast do
not allow any conclusion, but the preponderance of St. IV (50—g0 °/,) in 9 of 10 samples, scarcely
without any adult, is very remarkable, but does not give any information about the origin of the
specimens; 4 samples from the east coast show not much similarity to each other or to 2 samples,
from the Ingolf (St. r1or—1oz) with a considerable number of adult specimens. Paulsen concludes (p. 14).
“As there are practically no Ca/ani on the greater part of the North coast at the end of May and
beginning of June, and as Nielsen has shown with certainty, that the water here is renewed from
the west, we are entitled to conclude that the large quantity of Ca/ani on the north coast, as also

the young of the cod, have come with the Irminger current from the west.” Before accepting this

30 COPEPODA

theory, a much larger number of samples from May and June must be examined. Personally I think
that surface plancton like the Mauplius of Cf are carried by the cirrent from the south to the
north, increasing in size during the carriage, but also that not the smallest amount originates where
it lives, and begins to prosper when the Atlantic current makes its influence felt. Paulsen’s con-
clusion that from August stage V is predominant south of Iceland is proved by a big and varied
material; a few samples taken by the Ingolf south-east of the Fzeroes and of Iceland tells the same story.

Paulsen has from the month of September examined a few samples from the north coast
with St. V in the majority. Samples taken by the East Greenland Expedition north-west of Iceland,
in Denmark Strait and south of Iceland tell the same story.

Damas has in his interesting paper shown that the propagating of C.f took place 2*-3°/, 1904,
south of 67° L. N. where the Atlantic and the North Polar current meet. The material brought home
by the Amdrup Expedition tells exactly the same story for "4/6 1900, but as far north as 69° L. N.
Damas suggested that the majority of the specimens of C. f, which inhabit the Northern Ocean
took their origin from this region, and, by the Gulf-Stream, were scattered all over the ocean. He
writes (1905 p. 19) “Il est donc extrémement probable que nous avons par 14 reconnu le chemin suivi
par le renouvellement printanier des Calanides et lorigine des masses considérables de Calanus qui
peuplent en été le Nord de l’Océan et y jouent un réle si important.” Gran had, however, in his
well known paper (1902 p. 64), found the C. # in full propagation on the north-west coast of Norway
in April—May, Paulsen has from Lofoten examined specimens in propagating from 24/,—*/, 1899
and Damas and Koefoed (1907 p. 390—391) have found it spawning not only along the coast of
Norway but also in the fjords of Spitzbergen (?°-*8/, 1905). ‘The Duc d’Orléans has taken Cf $—?
near Cap Bismarck (76°49 L. N. 18°13 L. W.) 27/, 1905 in a depth of roo meter, 3'/, at St. 42 (78°06
L. N. 15°06 L. W.) 44—280 m. C. f was found cc (#—9) and at St. 47 (76°47 L. N. 15°21 L. W.) %/s
60—170 meter C. f was found cc (#—9). Even if no eggs or larve were found together with the
adults at these localities, their presence confirms my view that propagation of C. £ sometimes takes
place on a large scale on the east coast of Greenland.

Paulsen suggests in his concluding remarks “that the spring is perhaps not the only repro-
ductive period of Calanus finmarchicus, for the reason that we also find the adults of both sexes at
other times of the year almost everywhere, where fishing has been carried out in deep waters”,

In this he is probably right. He agrees with the different authors “that this species has its
principal reproductive period at any rate in the spring” (1906 p. 19). He is only right, if the spring
is defined as the period at which the waters reach a certain temperature and salinity, and which
varies according to the latitude from March (February?) to August (East Greenland).

2. Calanus hyperboreus Kroyer.
(Plate I figs. 1 a—d; textfigs. 6 a—b).

1838. Calanus hyperboreus n. sp. Kroyer, pp. 84, tab. IV, fig. 23. ; 1898. Calanus hyperboreus Kr. Giesbrecht & Schmeil,

1842-45. — _ Kr. — pil. 41, figs. 2a—g. p. 15.
1849. — — Kr, — pp. 542—542, 559. | 1899. — —_ — Th, Scott, pp. 90-91.
1892. — _ Kr. Giesbrecht, p. 91, taf. 6—8. 1897. o — — Vanhéffen, p. 278.

|

1898. -- — — Aurivilllus, pp. 88—89.

COPEPODA 31

1goo. Calanus hyperboreus Kroyer, G. O Sars, p. 2. 1905: Calanus hyperboreus Kroyer, Th. Scott, p, 221.
Igol. _ _ — Th, and A. Scott, pp. | 1905. ere _ — .G, O, Sars, p. 1,
338—339. 1907. — _— - Damas & Koefoed, pp.
1902. _ oo — Th. Scott, p. 450. 352-—358, 405.
1902. _ — — Mrazek, pp. 506—507. | 1908. — _ - Farran, p, 20.
1903. — — — Jensen, Johansen, Le- | 1908. _ _ — v. Bremen, pp. 8—9,
vinsen, p. 303. fig. 3.
1903. — — — G.O. Sars, pp. 12—13, | IgII. _ - _ Farran, pp. 89—g0.
pl. V. 1913. — Be — Stephensen, p. 71.
1903. ~ — — Norman, p. 135. 1913. — — — Stephensen, pp. 307—
1904. = _ — Wolfenden, pp. 112. 308.

Description. {9. Size varies from 7°5—9 mm.

The number of secretory pores differs from that of Calanus finmarchicus by the presence of
a “secretory pore”, (not in all specimens, as far as I was able to find out) laterally a little removed
from the base in Re III pes II in stead of corresponding to the wanting Se I; in pes III—IV the
pore was found at the same place as in Cal. finmarchicus, but was more distinct.

In the serration of the second basipodite of pes V it is, as shown by Giesbrecht (taf. 8 fig. 21, 23),
distinctly different from that of Cal. finmarchicus, in which species a serrated lamina is found; in Cad.
hyperboreus the number of teeth are smaller (about 25—35) and they ar not fused basally.

As far as the shape of the /aérum etc. is concerned I refer partly to the description of the
preceding species; only a few minor differences are dealt with here. The anterior process of the labrum is
more produced (text-fig. 6 a (d)). In the longitudinal series on the
oral surface (figs. 1 a—b) the two first groups are seen to be fused and
are diverging towards the free margin. In front of the lamina
labialis no granulation was observed.

Behind the lamina labialis (fig. 1c) and between the serrula
bidentata a dense group of hairs, medially more like short spines is
found; the arrangement is, as seen in the figure, somewhat different from
that of Cal. finmarchicus G. Behind, the group is separated into
two, of which the inner is continued between the lobi labiales, while

the outer is continued on the anterior surface of the lobe and thus

fused with the inner series of the lobes. The labial lobes (fig. 1 d), :

Textfig. 6 a—b.
bear 4—5 longitudinal series, of which the inner is the longest and cies

Calanus hyperboreus Kr,
6a. Head in lateral view. < 85.

group between the lobes, Behind the transverse list, between the © First abdominal somite. 85.

has the longest hairs; behind they are more or less fused with the

mandibular and the maxillular somites, laterally on each. side are found two groups of hairs, forming
together a semicircular figure. Between these groups, in the middle, a group, which is in front triangularly
pointed and behind the transverse line, which probably indicates the limitation between the maxillar
and maxillular somites, is widened. out and divided into two portions, between which a triangular
median group of dense hairs is found. More posteriorly a square group of densely placed short setae is
found in addition to one of fewer hairs just in front of the hinder limitation of the maxillar somite.

Laterally as seen in fig. 1d a few groups are found.

32 COPEPODA

Y. (St. V).. Size. 6 — 68 mm. (4°5 + 1°3).

This stage shows the same differences from the mature females as in Cal. finmarchicus G.,
it differs from that species, as in the adult females, by a pointed lateral corner, fewer teeth in the basipod. II
pes V marginally, by larger size and greater transparency.

Y. (St. IV—I). Size. of St. IV 3-7 mm. (299 + 08) — 4'5. Difference from Cal. finmarchicus as in
preceding stage, but number of spines at inner margin of basipodite II pes V 2—3. The stage III, which
varies in size from 26—3 (24—06) mm. the stage II, which varies from 18—1rgq mm. and the
stage I, of which I have not examined any specimen, seem only to be distinguished from the corre-
sponding stages of Cal. finmarchicus by larger size, as the character found in the pointed lateral
corner is wanting.

Occurrence. Specimens of Calanus hyperboreus have been taken all over the area investigated
by the different expeditions as far south as 51°00 L. N. 11°43 L. W., the S/S Thor has 15/5 05 taken
a single f?. (St. 82. Jt. 1200 M. W.)

West Coast of Greenland. On the west coast of Greenland it has been found by the Ingolf
Expedition from *?/.—!8/, 95 in 10 samples in the depth of 200—o fathoms. The stage IV has been
found in the greatest number of samples, but the stage V in the largest numbers; of the adult

females and stage III only single specimens were found; the youngest Copepodites seem to be wanting:

Number of
samples in Nah et, D “ Haak 3 Temp. |Percentage of] Number of
Stages. | which each ss eras ate So L. N.| . W. . oe at stages. specimens
stage is examined in| 1895. é:| fathoms. pirtate: | ecnined:
found. | 10 samples. «| VE) Vv fv
VI 4 6 25/695 | St. 24 | 63°06 | 56°00 | V.t 200—0 | 4:2°C. TPO Ts 105
/ 9
Vv 8 200 22/695 | St. 22 | 58°10 | 48°25 | V.t 200—0 | 574°C. 5 | 88| 7 65
IV 9 30 4A ve se er a
Ill 3 10

Bergendal has at Jakobshavn ?!/s 1890 taken a single f9.
Lundbeck has from 19/; 1889. 58°21 L. N. 48°43 L. W. 1 f9.
from 73/, 1889. 59°12 L. N. 52°05 L. W. 3 £9, 3 V.
26/; 1890. 57°08 L.N. 49°04 L. W. 10 f9, 10 V.
Soren Hansen 18/, 1885. 59°14 L.N. 51°18 L. W. 4 V, 10 IV.
Eberlein 12/, 1882. Umanakfjord. 1 f?, 4 (V), 1 IV.

Denmark Strait. The Ingolf Expedition has south-west of Denmark Strait (between 62°
L. N. and 58° L. N. and between 4o° L. W. and 26 L. W.) 7/6 1895 and from 1°/6-—*°/6 1896 taken
4 samples of which 3 contained together 6 {9, 3 respectively 12 V and 9 IV, and only 2 samples
containing 3 specimens of stage III. The same expedition has in the Denmark Strait 2°/, 1896 taken 5
f? and 25 V, 4/; 1895 1 £2 and 2!/; 1895 3 V + 3 IV.

The Thor has from **!/, r90q4 in Denmark Strait in 6 of 7 samples collected 180 f? and
104 V, but in 4 of 7 samples only 10 IV. At St. 154 2"/6 67°27 L. N. 27°10 L. W. the percentage of
196 specimens examined was f? 67°/., V 30°/. and IV 3 °%7/..

COPEPODA 33

South of Iceland. The Ingolf Expedition has south of Iceland '3/, 1896 St. 68 taken 2 V and
%8/; 1896 St. 54 3 f2 + 3.V. The Thor has *4/, 1904 (St. 104, 62°47 L. N. 15°03 L. W. Yt. 1500 M.
Wire) taken 25 ff and "/, 1904 (St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. W.) taken 20 f?, 10 V
and 1 IV. As the Danish East Greenland Exp. from *8/, 1900 has taken 50 samples (F. 312—366)
at the surface from Denmark Strait and 63 (F. 367—430) in the Atlantic Ocean south of Iceland
without any specimens, it is certainly right to conclude, that C. hyperboreus is only seldom found in these
regions at the surface.

Iceland-Feroe Channel. In the Iceland-Feroe Channel the Ingolf Exp. has from '-'/; 1895
taken 3 samples of which 2 together contained 8f and 2 V, one contained a single IV and one 3
III; 19 f? and 29 (V), contained in 4 samples, taken from '5~"/, 1896, were examined, but only 4 IV
(found in 2 samples) and a single (III). The Thor has 5/, 1904 (St. 63, 64°05 L. N. 9°38 L. W. Yt. 300
M. Wire) taken 10 f?, ro (V), 1 (IV), 22/; 1904 (St. 99, 61°15 L. N. 9°35 L. W. Yt. 1000 M. Wire) 16 f?
+ 7 (V) and 9/; (St. 70, 63°35 L. N. 6°20 L. W. Yt. 100 M. Wire) 175 f9. From 4/s 1904 (St. 230, 63°10
L. N. 7°31 L. W. Yt. 1200 M. Wire) 1 £9, 1 V and 1 1V were found. As far south as 57°52 L. N. 9°53 L. W.
Yt. 1500 M. Wire the S/S Thor has 8/6 1905 taken 16 £9 + 20 (V).

North Coast of Iceland. The Ingolf Exp. has on the north-west coast of Iceland collected a
large number of Cal. hyperboreus *7/, 1896 St. 125 with the stage V in majority; north-east of Iceland
as far north as Jan Mayen 11 samples with C. %. were taken from '*4/, 1904; 7 of these contained

£2, 7 (V), 4 (IV), 3 (III) and 2 stage Il; in all samples but one the stage IV—V formed the greatest
percentage.

, Devth i Temp. phy ot
Date. Ingolf.| L. N. | L. W. ae wits at VI Vv IV lll IL ed og
anon | surface. imens.
wiley St. 125 | 68°08 | 16°02 || Apst. 68 21° C. 25 Jo 74.%o| I Yo} .- .. |] 224
10/7 1896 | , ; :
4°30. p. m,. | St FOX | 66°23 | 12°05) Vt 100-0. | 55° C iad 16 I 7 5
Pa oye St. 59 || 65°00 | 11°16 | P. 100-0 16° C, 87. %o| 12 %o| 1%] .. ‘4 gI
11.15 p. m. ~ ro .. |-Apst. 12 r§°° Cl oe 21 - a
8 : “4
Be rae St. 117 | 68°13) 8°03 | V2 100-0 | 41° C. | 14 %o]13.5 %0] 36 %o| 35 %o| 1°5%lo] 150
Thor
22/, 1904 | St. 214 ||67°19| 17°55 Vt. 800 M.W.| .. 20 %9}| 27 Yo}.53 Yo] -.. e 75

Norwegian Sea etc. In the western part of the Norwegian Sea between 60° L. N. 3° L. E.
and 69° L. N. 6° L. W. the Danish East Greenland Expedition has not in any of the 84 surface
samples (F 1—8g9), which were collected from '9-?4/, and contained plenty of C. Ammarchicus, found
C. hyperboreus, With E. 14 a single f? was taken 21/6 c. 64° L. N. o'51 L. W. The same expedition
has near Jan Mayen with a closing net made several vertical hauls, and a few horizontal ones with a

big net, which makes it evident that the species was rather common in this region.
The Ingolf-Expedition. III. 4.

34 COPEPODA

Of 5 samples from Jan Mayen (?5/ 1 a. m.—5 a. m.) 4 contained f (21 specimens), 5 (V) (34
specimens) and 3 stage (IV) (6 specimens only); of 8 day samples 5 (taken 6 a. m. to 11 p. m.) did
not contain any specimens, but 3 (12 a. m.—3 p. m.) contained together g f9.

Number of
Date. G.Exp. 1900 | yy | y | iv | m | | 1 [specimens
at Jan Mayen. ovninineds
25/6 12°30 night | Horizontal net. | At the Surface || 87 %%o|13 %0| .. ae Pas I 100
25/6 Closing net. 50—60 fathoms|| 10 17 I ot "es
28/6 ? bee 20 2 3 4 Shirt “ae
1/7 I p. m. Closing net. 25 —I10 10 | 40 %o| 21 %o| 29 %o} .. | .. 60
ae 50 —25 I 3 :
100—50 I 4

From the 78/s 10 p. m.—?/, 1900 the East Greenland Exp. has near Jan Mayen collected c. 40
samples (F. 907—135); 27 day samples (6 a. m.—7 p. m.) were taken, of which only F. 125 ('/, 1912

mid-day 71°31 N. 7°43 L. W.) contained a single f?; of 13 night samples the 4 following contained
C. 4, and the {2 most abundantly.

Number of
@.Exp. 1900.| VI v IV || specimens
examined.
28/6 10 p.m. | Jan Mayen F. 90 85 %o | 15 %o} .. 106
II p.m, os - gl 5 4 I
12 p.m. os - 92 4o 4 Be
29/6 I a.m. si - 93 3 15 6

In the ocean tract crossed by the East Greenland Expedition from 2/, 1 a. m, to 9/, 12 p. m.
between 73° L. N. 4° L. W. and 74° L. N. 11° L. W. 109 samples (F. 136—244) were taken, partly
along the ice-edge or among scattered ice. As is easily seen in the following table the adult females
are the most frequent; the species is rather scarce at the surface and there is not seen to be any
marked difference in its occurrence in different times of the day.

Number of | Number of
les samples | Number of | Number of
O. Exp. 2-9/7. parr P
St It without | containing £9. stage V.

C. he. Ch.
Number of samples and f 5 a. m.—7 p. m. 43 16 : 54 6
specimens taken U8 p. m.—4 a. m. 40 10 12 6
Summa 83 26 66 12

That the species was well represented in the greater depth even at localities in which it was
scarce at .the surface is shown by a few vertical hauls (cf. table p. 35).

COPEPODA 35

By Deichmann 3 f?-+ 5 (V) were taken as far north as 75°37 L. N. and 6°40 L. W. As the
Danish East Greenland Expedition from the coastal waters only took the species in the few above
mentioned samples, and as not one was found in 13 surface samples (F. 244—262) taken from 9/,—"7/, in the

Number
Date. | LN. | Lw.| % EP | vi | v | Iv lof spec-
= aay imens.

4/7 3 p.m. | 73°32 | 3°30 || 300—om. || 83% | 16%] 1% |) 114
8/, 2 p.m. | 74°09 | 11°31 || 400—-om., || 23 I 3
1o/, 6 a.m. | 74°28 | 15°36 || r110—om. 7 15 I
16/7 72°02 | 21°20 || 35—I10 2 I

sea north-west and west of Jan Mayen, and as not one was collected in 47 samples (F. 265—310) taken
on the voyage home from 3°/s—4/, between Forblasfjord and 67° L. N. 23° L. W., there is reason to suggest
that the species was not very common in the mentioned period.

Distribution. This species has its main area of distribution in the North-Polar Basin, (but has at
the present only been found as far east as 136 L. E.}, where its propagation probably takes place; it is
found at the surface as well as in the lower layers. In the waters, which connect the polar seas, it is equally
found viz. the Bering Strait (von Bremen), the Barents Sea, the Davis Strait (Ingolf Expedition,
Vanh6ffen and Stephensen in Karajakfjord), but especially in the ocean between Spitsbergen and
the east coast of Greenland. It was here found from the surface or 5—10 met. below it, when there
was floating ice, down to about 1000 meters. Probably carried by the north polar current it was found
in the North Sea, but generally in small numbers and in the lower layers. The area around Iceland
in which it occurs in abundance “coincides almost exactly with the path of the east polar current
and takes the form of a broad tongue passing in a south-easterly direction between Iceland and Jan
Mayen and reaching almost as far as the Feeroes” (Farran p. 89). By the south-going bottom current
it is probably carried over the Wyville Thomson’s and the Iceland-Fzroe ridges, and is accordingly
found scantily in the deeper layers of the North Atlantic as far south as 54° L. N. on the west coast
of Ireland. By the assistance of the Labrador- and the Kuro-Sivo currents the species is probably in a
similar way distributed over the West-Atlantic and the Pacific. In the Skager Rak and the deep fjords at
the west coast of Norway it is sometimes found abundantly, according to Sars, as a relict fauna. If
he is right, it should be possible to find it in propagation here. It should be interesting to know, if
the species in the deep Atlantic is sometimes propagating, or if the stock must be renewed. The
temperature under which this species is found abundantly, lies between +19 and + 6°, the salinity
between 33°15 %/oo and 35°18 %/o. About the details in the biology and distribution of this species I refer
to the papers of Farran and Damas-K oefoed,

Remarks. This species is in the three last stages easily distinguished from Cal. finmarchicus.
But the distinction in the earlier stages, in which the difference is only found in the size etc. may,
as pointed out by Damas & Koefoed, be very difficult if not impossible, especially in the polar sea,

where Cal. finmarchicus attains a size of 5 mm. or more.

36 COPEPODA

Macrocalanus G. O. Sars.

1883. Calanus pars Brady. 1907. Megacalanus G. O. Sars.
1905. Macrocalanus. G. 0. Sars,.- | 1908.. Megacalanus Farran.
1906. Megacalanus Pearson. 1909 . Bradycalanus Scott p. 14.

1906. Heterocalanus Wolfenden. | 1911. Heterocalanus Wolfenden p. 201.

Since Wolf enden, as the first, established a new genus, A/agacalanus, for a big Calanoid from
the deep Atlantic, four other genera viz. Macrocalanus G. O. Sars, Heterocalanus Wolfenden, Bathy-
calanus G. O. Sars, and Bradycalanus Scott, more or less related to the original one, have been
established. A good deal of confusion about the right definition of these genera has risen. Scott
and Wolfenden have both tried, but only with partial success, to find the right names for the most
natural groups of species.

About the genus Bathycalanus G. O. Sars not much discussion in necessary. By Sars it was
characterized by the ribbon-shaped and- densely-ciliated bristles on the lobes of the maxillae and
maxillipeds, and by the two-segmented Re of pes I; the described species (B. Richardt) has 2 distinct
spines covering the rostral filaments and “assez gréles” rostral processes. As Wolfenden has examined
a specimen of B. Richardi G. O. Sars with indication of segmentation between Re II and III pes I,
and as his other species B. maximus Wolf. has a three segmented Re pes I (without Se as in the
other species) and with long and stiff rostral processes, he regards the structure of the maxillae +-
maxillipeds and the frontal teeth as the most important character (p. 198). Scott (1909 p. 11) is certainly
wrong in not accepting Bathycalanus maximus Wolf. as belonging to Sars’ genus on account of the
differences in the segmentation of Re pes I.

Wolfenden writes (1911 p. 201) “Ob die Charaktere dieser drei Gattungen geniigen, um ihre
Abtrennung von einander zu rechtfertigen, kan Ansichtssache sein; wenn aber die generische Unter-
scheidung von Bathycalanus und Megacalanus anerkaunt wird, so erscheint auch die Abtrennung von
Heterocalanus. als eigene Gattung berechtigt, denn Heterocalanus unterscheidet sich von jeder der
beiden andern Gattungen deutlich durch die Bewaffung der Maxillipeden, die Form des Kopfes und
den Bau des 5 Fusspaares”. From this point of view Wolfenden as well as Scott (1903 p. 11) are right,
and Sars wrong in referring his Macrocal. princeps and longicornis to the same genus, but his
Bathycalanus Richardi to a new genus. The genus Megacalanus Wolf. with MZ princeps Wolf. as the
type is characterized by the hook on the anterior surface of the Basp. III pes I and the slender bristles
of the maxillae. Wolfenden, who rightly recognised that Brady’s Calanus princeps is‘ nearly
related if not identical with his Heterocalanus medius, ought in every case in his later publications to have
accepted Sars name Macrocalanus, which according to the general rules of nomenclatures had priority,
especially as Mac. princeps Brady is naturally regarded as the type of the genus and as the name
Heterocalanus has been previously used for anothed genus of Calanoids. In the Report from the
Siboga Expedition, Scott (p. 44) established a new genus Bradycalanus with a single species B. ¢ypicus,
which differs from Heterocalanus by the head without crest, by the pointed lateral corners of the
last thoracic somite, and by the well developed Se of Re I—II pes I and 2 Se Re III of pes I. He
writes: “I think that it is probable that Brady’s Calanus princeps belongs to this genus rather than
to Bathycalanus or Heterocalanus”; accordingly, instead of establishing a new generic name, he ought

to have accepted Macrocalanus G. O. Sars.

COPEPODA 37

Scott suggest that Heterocalanus medius Wolf. is identical with Kréyers Calanus cristatus;
this species, of which I have examined the type specimens, is however a true Cadanus (cf. p. 11).
On account of the existing confusion I think the following synoptic key will be useful.

1. Strong hook on anterior surface of basp. III pes. 1; pes I—IV with 3 segmented Re and Ri. The

‘maxillae without densely plumous setae in distal lobes Megacalanus 2.
1. Strong hook on anterior surface of basp. III pes I wanting as
2. 3 Se of Re III of pes II—IV Megacalanus princeps Wolf.
2. 2 Se of Re III of pes I—IV Calanus gracilis Dana.
; Calanus robustior Giesb.
3. Maxillae without densely plumous setae. 2 Se of Re III of pes II—IV Calanus
3. Maxillae with densely plumous setae. 3 Se of Re III of pes II—IV 4.
4. Maxillipeds with slender setae Macrocalanus. 5.
4. Maxillipeds with densely plumous setae. Re pes I without Se. Front with 2 conical processes

Bathycalanus G.O.Sars. 6.
5. Frontal crest. Rounded lateral corner. Pes I has no Se in Re I—II, one Se in Re III
Macrocalanus (FHeterocalanus) princeps Brady.
5. Frontal crest wanting. Pointed lateral cornes. Pes I has 1 Se in Re I—II, 2 Se in Re III
| Macrocalanus (Bradycalanus) typicus Scott.
6. Re pes I two segmented. Rostral processes rather slender Bathycalanus Richardi G. O. Sars.
6. Re pes I with 3 segments. Rostral processes long stiff rounded Aathycalanus maximus Wolf.

3. Macrocalanus princeps Brady.
(Pl. I figs. 2a—b; textfigs. 7a—b).

1883. Calanus princeps n. sp. Brady, pp. 36—37, pl. IV | 1906? Heterocalanus medius n. sp. Wolfenden pp. 27—28.
5; figs. 3—7. || pl. VIII figs. 1—s.
1904 nec. Megacalanus princeps n.sp. Wolfenden pp. 112—113. | 1908. Megacalanus princeps Brady. Farran p. 21.
1905. Macrocalanus princeps Brady. G. O. Sars p. 7. Ig1i nec. Megacalanus princeps Wolf. Wolfenden pp. 196—198.
1g05 nec. Megacalanus princeps Brady. Wolfenden pp. 3—5 | Igtr? Heterocalanus medius Wolf. Wolfenden pp. 201—202
5 “pl. I figs. 7—9. taf. XL figs. 1—5.
1906, Megacalanus princeps Brady. Pearson p. 6. :

Description f£9. Size. Anterior division 55-5 mm; posterior 3 mm; total length 13:5 mm. The
body is slender, as the anterior division is about 2°5 as long as wide. The first as well as the fifth somite,
the lateral corner of which is regularly rounded (fig. 7b), are well distinguished. The head has a low
crest terminated by a small frontal process. The rostrum consists of two powerful rounded spines,
parallel and directed downwards. At the base slender rostal filaments protected above by low pro-
cesses. The hinder margin of the head has dorsally a small elevation bearing a conical process. The
urosome consists of four somites, of which the first — the genital one —, ventrally produced in front,
dorsally behind, is distinctly wider and deeper than long, and distinctly twice as long as the following
somites. The furcal rami are-a little shorter than the third somite and 1-2 as long as wide.

The antennulae project at least 6 segments beyond the tip of the furca; they consist of 25
segments, of which, however, the 8 and 9 are less well separated. The segments increase in length

38 COPEPODA

from the 8 to the 17 segments, but decrease from the 20 to the 24, which is scarcely half as long as
the 23, which is of almost equal length to the 25. In the basal segment only 2 terminal setae are
observed; the second segment bears three tritheks, and the following 17 segments bear a single one,
consisting of rather delicate setae; the 20—23 segments have only 2 terminal setae (Sd -+ “Aisthe-
tasken”), the 24 segment has a single long and slender seta and the 25 segment has 6. Segment 22
has a delicate posterior seta (Sp.) and the two last segments each bear a powerful, ringed plumous
one, at least twice as long as the two segments combined.
Antennae are in the main alike Ca/anus, but the Si of the Basipodite II is very short and
the Re I and II have no Si, but the latter segment has two processes medially.
Mandibulae: The manducatory part is rather short with the first to the fifth serrations well
developed without accessory teeth; the sixth to the eighth serrations are only poorly developed. The
four partly plumous setae, of about equal length, are shorter than the width of
the segment. The Ri I has only 2 setae and the Ri II has 8 setae anteriorly
and a single one posteriorly.

Maxillulae: The Le I has the 2 first setae extremely short, almost
rudimentary, and the following 7 long and plumous; the Le II is only indistinct
without any seta. The Li II, which does not bear any seta, is comparatively
shorter than Li III, which is fairly slender with 2 setae only. The Basp. H has
2 moderately slender setae (Sp.?); the Ri I—II which are indistinctly separated

from each other as well as from the basipodite, have a single seta each, while
Textfig. 7.
Macrocalanus princeps
Brady. a. Head of adult which has the usual eleven plumous setae, extends a little beyond the end of
male, x 8°5. b. Abdomen,
X 85.

the well distinguished Ri III bears 4 long and one single rather short seta. Re,

the endopodite.

Maxillae are in most respects alike Ca/anus, but the Lob. V bears
anteriorly 2 long slender ribbon-shaped setae, and the Ri, which has the articular membranes rather
indistinct bears six setae of the described structure.

Maxillipes: The proportions of Basp. I~ II, Basp. III and Ri = 55:50:30; they are in the
main alike Calanus, but Ri II—IV have only a single seta each, and Ri V has 2 Si+1 Se.

Legs are comparatively short and broad and have three segments in exopodites as well as
in endopodites. In the first pair the Re I—II has no Se and the Re III has only a single one, placed
a little nearer to base than tip. The Re I—III has1-+1-+ 5 Si (ci. Wolfenden t. XI fig. 5, in which,
however, the Se Re III is placed distinctly nearer tip than base). The second pair of legs has the
Ri extending just beyond the end of Re II; the Re I—II is 11 shorter than Re III, but 16 as long
as the distinctly serrated St.; the Re I—II have each a Se and the Re III has 3. The third and
fourth pair of legs are in the main features alike the second pair. The fifth pair of legs is smaller
than the others and differs in several respects. The inner margin of the basipodite II and III are
almost straight, thus differing distinctly from pes. II, and in a less degree from pes. II—IV. The Ri
extends beyond the base of Re III to the insertion of Se 2. The Re I—II have each one Se and the
Re III has 2; the number of Si is 4 in Re III and 1 in Re II, but the Si is wanting in Re I.

Secretory pores are in pes II found on the the anterior surface at the base of Se Re II

al al:

Se a a ee

ota

COPEPODA 39

and the Se I—III of Re III, and, surrounded by a number of fine hairs, somewhat removed from tip,
on the anterior surface of Ri III; in addition to these the pes III—V have a pore at the base of Se
Re I, and so has pes V, in which, however, only 2 pores are observed in Re III.

The number as well as the arrangement of the “maculae cribrosae”, of which none was
observed in the mouth-appendages, is less regular than in M/egacalanus. On the anterior surface of
Re I, at base of Se, the organ was observed in pes II—III, but not in pes IV. On the posterior surface
the maculae were sometimes found near the base of Se ReI pes II, and regularly in pes II as well as
pes III near the base of Se Re II and Se I—II Re III; in pes IV only a single group was observed
in Re II.

On the anterior surface of pes II—III, medially to insertion of the Re, a group of delicate fila-
ments, projecting through minute pores (?) and perhaps corresponding to a macula cribrosa, was found.

The lateral outline shows, somewhat in front of the labrum, a low rather elongated elevation.
In the middle, as well as on each side, well removed from the hinder margin, a group of fairly long
and slender, delicate hairs are observed. ‘The posterior margin has a median incision, and well removed
from the middle on each side a transverse marginal row consisting of about 15 short lancet-shaped
spines (fig. 2a). On the oral surface the usual longitudinal series is dissolved into 5 more or less trans-
versely placed groups, as shown in fig. 2a pl. I; the bristles of the more posterior groups are more
slender and longer than those of the anterior ones; between the group (Nr. 4) on each side and behind
the fourth central spot a transverse row of granules is found.

The lamina labialis has 1 median and on each side 2 lateral teeth; in front of this we
have an exterior and mostly anteriorly slightly convex series of rather long bristles and an interior short
one of shorter bristles (pl. I fig. 2b). The serrula 6-dentata has the 4 posterior spines club-haped;
between these and the labial lobes scarcely any setae were observed. The area labialis has behind the
labial lobe a median somewhat convex group, and a lateral oblique group of numerous hairs on each
side; the labial lobes bear about 8 groups of shorter and longer hairs, which seem to be arranged in
3 series. f

Y (St. V). Size: 84+ 22 —= 106mm. The shape of body is scarcely different from that of the
f? except for the urosome, which has four somites, hardly produced beneath, of which the second
is almost twice as long as the first, which is the shortest. The antennulae extend only 4 segments
beyond the end of the furca; the measurements differ in minor points only; the maxillulae have in
one specimen only a single seta in the basp. III in another 2 as in £9. The Re has only to setae.
In other respects no difference was observed.

Y (St. Ill). Size 61—63 mm. (1°10 + 0°53).

Of this stage I have examined 2 specimens; in spite of the different shape of the head and
the short antennulae I do not doubt that the animals are rightly referred to this species, as they agree
with it in several important features e. g. the curious structure of the maxillulae.

The body in much more slender, and the head shows no trace of a frontal keel; the first as well
as the fifth thoracic tergite is well marked. The urosome consists of 2 somites, of which the second
is almost twice as long as the rostrum as well as the furcal branch. The antennulae, which just

reach beyond the end of the abdomen with the tip of the last segment, consist of 23 segments; the

40 COPEPODA

25 is 21 as long as the 24 and 1'1 as long as the 23. The Le as well as the Re of the maxillulae
have only 11 setae. The distal setae of the maxillae show indication of the curious structure found
in the full-grown. The pes I—III have the Ri II~III and the Re IIWIII fused; the Re II~ III pes
II has 3 Se and 5 Si; the Re II~III pes III has only 2Se; and its Ri has 8 setae. The pes IV
has Ri Iw III fused with 7 setae and the Re I~wIII has 3 Se and 3 Si. The fifth pair of legs is, as
shown in Cal. finmarchicus, quite rudimentary. In contrast to the full-grown female a distinct pore
was found at the base of Se basp. III of the pes II—III; in addition to this a pore was found at the
base of Se Re I and Se 3 Re III.

Occurrence. This species has not been captured by the Ingolf Expedition, but the Thor
Expedition has taken it from the following stations 1904 and 1905.

Thor "9/6 1904 St. 152 65°00 Lat. N. 28°or Long. W. Yt. 1000 M. Wire 2 f9.
to/, 1905 St. 180 61°34 Lat. N. 19°05 Long. W. Yt. 1800 M. Wire 3 f9.
1t/, 1904 St. 183 61°30 Lat. N. 17°08 Long. W. Yt. 1800 M. Wire 4 £9; 2y (V); 2 (IID).
25/, 1904 St. 104 62°47 Lat. N. 15°03 Long. W. Yt. 1500 M. Wire 1 f9?.
22/, 1904 St.gg 61°15 Lat. N. 9°35 Long. W. Yt. 1700 M. Wire 1 f9.
7/6 1905 St. 71 57°47 Lat. N. 11°33 Long. W. Yt. 1500 M. Wire 2 f9.
8/6 1905 St. 72 57°52 Lat. N. 9°53 Long. W. Yt. 1500 M. Wire 2 f9.
1t/, 1905 St. 167 57°46 Lat. N. 9°55 Long. W. Yt. 1500 M. Wire 3 f9.

Distribution. This species has previously only been recorded from the great depths in the
Atlantic Ocean viz. from the west coast of Ireland as far north as 55° Lat. North, from the North
Atlantic (c. 40° Lat. N. 70° Long. W.) and the Mid Atlantic (c. 10° Lat} N. and 20° Long. W.). As it
has not been taken by the Siboga Exp., it is rather doubtful if it is found in the Indian Ocean.

Remarks. It seems to me scarcely doubtful, that the described species is identical with Brady’s
Calanus princeps; this author writes: The abdomen is short, stout and three-jointed. The latter character
is certainly due to a mistake. His fig. 5 of the maxillula shows, probably wrongly, only 6 setae in Le
I and 10 in Re. As I have examined specimens, identified by Sars, it is scarcely doubtful that the
species is identical with Sars and Farran’s Megacalanus princeps Brady. Farran has suggested, that
Wolfenden’s Heterocalanus medius is identical with Cal. Arinceps Brady, and I think he is right. My
specimens differ from Wolfenden’s fairly exhaustive description (1906 p. 27) in the following features:
1) Le I maxillulae has 9 instead of 7 bristles and the 2 setae of basp. II are not “very short and

delicate”. 2) the Se Re III pes I is placed nearer the base than the tip.

Megacalanus Wolfenden.

1904. Megacalanus, Wolfenden. | 1908. Megacalanus pars, Farran, p. 21.
1905. Macrocalanus pars, G. O. Sars. 1909. Megacalanus, Scott, pp. 10o—12.

1905. Megacalanus pars, Wolfenden. Ig1t. Megacalanus, Wolfenden, pp. 195—196.
1906. Megacalanus pars, Pearson, p. 6. ‘

The type of this genus, which is probably more related to Caldanus than Macrocalanus and

Bathycalanus, is M. princeps; it is well characterized by its size and the curious hook on the anterior

COPEPODA 4I

surface of the third basipodite of the first pair of legs. Scott has proposed to refer Calanus gracilis
Dana and Calanus robustior Giesbrecht to the same genus, in spite of smaller size, on account of
a similar hook. Possibly he is right; but as I have not had the opportunity of examining any spec-
imens of the two said species, I do not feel competent to judge in the case.

3. Megacalanus princeps Wolfenden.
(Pl. I figs. 3a—i; textfigs. 8 a—d).

1904. Megacalanus princeps n. sp. Wolfenden, pp. 112--113. | 1906. Megacalanus longicornis G. O. Sars. Pearson, p. 6.

1905. Macrocalanus longicornis n. sp. G. O. Sars, p. 7. 1908. Megacalanus longicornis G. O. Sars. Farran, p. 21.
1905. Megacalanus bradyi n. nom. Wolfenden, pp. 1—3, pl.I, | 1909. Megacalanus princeps Wolfenden. Scott, pp. 13—14,
; figs. 1—6. pl. I, figs. 12—18.
1905. Nec. Megacalanus princeps Brady. Wolfenden, pp. 3—4, | 1911. Megacalanus princeps Wolfenden. Wolfenden, pp. 196
pl. I, figs. 7—9. —198, taf. XXII, figs. 1-11.

b

Text-figure 8.
Megacalanus princeps Wolfenden.
a. Head of adult female 16. b. Abdomen of adult female x 16. c. Pes I in situ * 67.
d. Abdomen of young female (stage V) 16.

Description f9. Size: 10°5 mm. (anterior division 8:5; urosome 2). The head is slightly produced
between the base of the antennulae and is without any crest. The rostral filaments are short and placed
on a low elevation just above the rostrum, composed of a short basal part and two slightly convergent
rather obtuse, fairly long spines, directed backwards and downwards. The five thoracic somites are well
distinguished; the fifth is laterally triangularly produced. Projecting from the hinder margin of the
head a small process, similar to that of Macrocalanus, though less prominent, is observed.

The abdomen is only one fourth of the anterior division in length. The genital somite is as
long as deep and wide, and in front ventrally produced.

The antennulae, which are at least 8 segments longer than the body, have all 25 segments
well separated, except the VIII and IX, with the articular membranes wanting posteriorly. The
segments increase in length from the 8 to the 17; beyond the 19 they are much shorter; the 23 is 14
as long as the 25, which is only rr as long as the penultimate one. The 13 and 14 have in the distal
part, ventrally and exteriorly, a row of delicate teeth (according to Wolfenden they are found in seg-
ment 12 and 13). The bristles of the antennulae are rather delicate; the posterior setae of segment

23—24 are rather weak, and scarcely 1°5 as long as two distal segments (in Scott’s figure they are
The Ingolf-Expedition. III. 4. 6

42 COPEPODA

distinctly twice as long). The arrangement and number of setae are alike that of Macrocalanus, and
agree with Ca/anus by the presence of a single seta instead of two in segment 21.

Antennae are in the main alike those of Ca/anus (cf. Wolfenden), but the Re II is by an
incomplete articular line divided into a proximal division, bearing two setae, and a shorter terminal one
with a single bristle.

Mandibulae (figs. 3 a and c) cf. Wolfenden (taf. XXII fig. 5) have a well developed manducatory
portion with five distinct teeth and a few more or less fused.

Maxillulae are alike Calanus jinmarchicus in most features, but differ by comparatively long
Re, and by the presence of 3 setae instead of 4 in Ri I (as seen in Wolfenden’s fig. 2).

The Maxillae (fig. 3d) and Maxillipeds are as described by Wolfenden (taf. XXII figs. 4
and 6) in the main features alike those of Ca/anus, but the former organ has the fifth lobe comparatively
long with a thin hook, and the latter has the hairs, which cover the anterior surface of the Basp. III
proximally and medially bifurcate or divided into three branches, and the Se of Ri 4—5 are compara-
tively short and unarmed.

The five pair of natatory legs have three segments in exopodites and endopodites; in basipod
III pes I a characteristic structure is found in the upwards directed hook, which dorsally in the concavity
has arather irregular process, and ventrally bears the slightly plumous Si; this hook is indicated in
most species of Calanus and in Macrocalanus as a small process on which the Si is placed (cf. Giesbrecht
p. 110). Pes II has the inner margin of second basipodite almost straight (cf. fig. 3 e). Thes pes III—IV
is in main features alike pes II, but Ri II with distinct Se. The pes V (fig. 3 h) is in general structure
like the preceding pairs, but is distinctly shorter; the inner margin of basp. has no hairs and no Si.

Glandular pores, surrounded by prominent rings are observed in the pes II—IV, as shown in
fig. 3e at the base of Se basp. III and Re I—III, and are observed surrounded by fine hairs distally
on the anterior surface of Ri III; the last mentioned pore and the pore corresponding to the wanting
Se 1 Re III are absent in pes V.

Maculae cribrosae: In the legs and in a less degree. in the other appendages small spots,
consisting of a more or less circular ring of minute pores, continued into a delicate threadlike glandular
duct? (fig. 3 fg), are observed. '

As the arrangement of these, “maculae cribrosae” seems to be fairly regular, and as I have
only observed them in Megacalanus and Macrocalanus, I think they are of some systematic importance
and hope that the following account of their number is fairly exhaustive; they are often rather diffi-
cult to observe. The antennulae possess on the upper surface of the second segment a group of 9
pores; on the anterior surface of the Ri I of the antennae, at the base of the distal third, a group
of about 15 pores is observed. The manducatory part of the mandibulae bears at the base of the
serrations at least a single group, and the basp. III at least 2 rings of 7 pores anteriorly. The maxillulae
bear on the anterior surface a group of 14 pores at the base of Le I and basally near the lateral
margin of Re. In the maxillae a single group of 12 pores is observed on the anterior surface of the
first basipodite and near the outer margin.

On the posterior surface of the first pair of legs no pores are found; anteriorly a group of 10
pores is observed in basip. III medially to the articular cavity of Re I, and another one is seen in the

COPEPODA 43

middle of Ri II. In the second pair of legs, on the anterior surface, pores are found near the lateral
margin of basip. II (on the left side a single group of ro pores and on the right side two groups of 6 pores),
in the basip. III medially to the insertion of Re I and in ReI near base of the process bearing Se; on
the posterior surface of basip. II, and at base of Se Re II and Se 1—2 Re III, a rather indistinct group of
pores is found. In the third and fourth pair of legs, groups of pores are also found posteriorly at base
of Se basp. II and Re I; in the fifth pair of legs only a single group was found in Re III posteriorly
(at base of Se J).

As the number and arrangement of the maculae cribrosae in the mature male are scarcely dif-
ferent from those in the female, and as only the groups in the maxillulae, but not those in the nata-
tory legs, were observed in the Copepodites (stage IV—V) it seems to be possible, that the main-
purpose of the maculae cribrosae is connected with the sexual life (e. g. light organs).

In front of the labrum and well distinguished from it, a fairly prominent elevation is found.
The /aérum itself is rather elongated (Pl. I, figs. 3a—b and text-fig. 8a). Anteriorly a transverse row
of delicate hairs is found, and posteriorly on each side of the median incision a transverse marginal row
of about 25 rather short lancet-shaped spines in addition to two somewhat convex rows, and a small group
of delicate hairs. The oral surface of the labrum has in front two well separated oblique groups. The
three following groups are placed more longitudinally as seen in fig. 3b. Only corresponding to the
fourth central spot a few hairs are seen in a transverse row. The /amina labialis is, as seen in fig. 3¢,
fairly distinct without serrations; in front of this an outer convex series consisting of fairly long hairs,
in continuation of the serrula 6-dentata, and three inner series of very delicate hairs are observed.
Behind the lamina labialis, between and upon the labial lobes and behind these a number of series and
rows of delicate hairs are found; about theit arrangement I refer to fig. 3a.

fg. Size: 106 mm. (anterior division 8:5; urosome 2'1), The body is more slender and the process
of the posterior margin of the head is better developed. The abdomen consists of 5 somites, of which
the second is 2°5 as long as the first and 1:2 as long as the third.

The antennulae (Pl. I fig. 3i) have the articular membranes between the 7—9 segments less
well developed than between the preceding and following ones. The number of the bristles shows a
similar difference from that of the female as in Calanus. The “A®stetasken” are powerfully developed and
the Sd of segment 9 is represented by a clavate structure (fig. 3i). The other appendages do not show
any difference from those of the females except the fifth pair of legs. In these the basp. and Ri are
scarcely different, but the Re have no Si except the Re II of the pes V sin, which has the Si(?)
represented by a stumpy articulated process, prolonged into a somewhat twisted feathery spine, at the
base of which long and stiff hairs are seen; marginally a dense seam of hairs, as figured by Wolfenden
(fig. 9), is seen.

Y. (V). Size: 8:2 mm. (anterior division 6:5, urosome 17). The shape of body is in main as in f9,
but the lateral corner is more pointed and the urosome consists as seen in fig. 8d of four somites, of
which the first one is prominent ventrally, The mouth appendages seem in the main features alike
those of mature females; the Re of the maxillulae possess as usually 10 for 11 setae. The second
pair of legs differs by comparatively short Ri, which does not extend to the end of Re II, and by

the wanting glandular pore at the base of Se I Re III; the same pore is wanting in the fourth pair
6*

44 COPEPODA

of legs and the corresponding Se is distinctly smaller than the following. The fifth pair of legs
has the Ri II—III fused with the usual number of setae, as well as the Re II—III, bearing 3 Se (pore
at base of Se I missing) and 5 Si.

Y. (IV). Size: 68 mm. (anterior portion 5°5; posterior 1°3). The body differs distinctly by a three-
segmented abdomen; the first somite, which is slightly produced beneath, is the shortest, and 1-6 shorter
than the third one. The antennulae, especially the distal segments, are comparatively longer; the
number of setae differ in several details. The maxzllulae differ by a smaller number of bristles in
Ri (Ri I has f£ inst. only 2 setae) and by 9 setae of Re. The first pair of legs have the Ri II —III
fused with 8 setae, and the Re II—III with 3 rather slender Se, but only 4Si. The second pair of
legs has the Ri II—III fused with 9 setae, and the Re II—III fused with 3 Se and 5 Si; glandular
pores as in preceding stage. The fourth pair of legs has 7 setae in Ri I~ III, and 5 Si and 3 Se,
of which first one without glandular pore, in Re IIWIII. The fifth pair of legs has the Ri I~ III
with 6 setae and the Re IwIII with 3 Si, 3 Se and a St. only a single pore at base of Se III
is found.

Occurrence. This species has not been captured by the Ingolf Expedition, but has been taken
at the following stations in deep hauls by the Thor r9g04—1905 south and west of Iceland.

Thor "9/6 1904 St. 152 65°00 Lat. N. 28°00 Long. W. ry (IV).
"3/, 1903 St. 164 62°10 Lat. N. 19°36 Long. W. 1 £9.
10/, 1904 St. 180 61°34 Lat. N. 19°05 Long. W. Yt. 1800 M. W. 2 £9; 3 fot; ry (V).
11/, 1904 St. 183 61°30 Lat. N. 17°08 Long. W. Yt. 1800 M. W. 4 £9; 4 fd‘; 5y (V); ry (IV).
24/. 1904 St. 104 62°47 Lat. N. 15°03 Long. W. Yt. 1500 M. W. ry@ (V).
12/, 1904 St. 78 61°08 Lat. N. 9°28 Long. W. 1 £9.
29/3 1905 St. 167 60°00 Lat. N. 10°35 Long. W. Yt. 1000 M. W. 1 f9.
3t/s 1905 St. 167 57°46 Lat. N. 9°55 Long. W. Yt. 1500 M. W. 1 £9; ry (V); ry (IV).
8/6 1905 St. 72 57°52 Lat. N. 9°53 Long. W. Yt. 1500 M. W. 1 £9; 1 y (IV).
23/, 1905 St. 124 61°04 Lat. N. 4°33 Long. W. Yt. 1000 M. W. 1 f9?.

Distribution. This species seems to be fairly common in the Feeroe-Shetland Channel, and on
the west coast of Ireland between 600 and 1000 fathoms. It has been taken in the Atlantic by the
Gauss Expedition as well as at a single station in the south polar region (c. 65° Lat. S. c. 85° Long. E).
By the Siboga Expedition it has been taken at three stations at about 4° Lat. S. 129 Long. E.

Eucalanidae.

5. Rhincalanus nasutus Giesbr.
- (PL I figs. 4a—e).

1877. Rhincalanus gigas Brady. Mdbius. 1898. Rhincalanus nasutus Giesbr. Giesbrecht & Schmeil pp.
1888. _ nasutus n. sp. Giesbrecht, p. 334. 22—23.
1888. -- gigas Brady. J.C. Thompson, p. 148. IgoT, — gigas Brady Th. Scott, p. 237; pl. XXVII
1892. — nasutus Giesbr. Giesbrecht, pp. 152—158, figs. I—4.

taf. 3, 12 and 35.

COPEPODA 4S

1902. Rhincalanus gigas Brady. Th. Scott, p. 450. 1905. Rhincalanus nasutus Giesbr. G. O. Sars, p. 2.

1902. _ nasutus Giesbr. G. O. Sars, pp. 15—16 pls. | 1905. - ‘kets — Th. Scott, p. 222.
VI—VII. 1905. _ — — Esterly, p. 137, fig. 10.

1903. _ (oe — J.C. Thompson, p. 16. 1905. —- — — Wolfenden, p. 996.

1903. _- _. — Thompson & Scott, p. 242. | 1906. - = — Pearson, p. 8.

1903. — — — Norman p. 135. 1908. — _ — Farran, p. 22.

1903. _ — — Cleve, p. 368. 1908. — _ — vy. Bremen, p. 18 fig. 14.

1904. — = — Wolfenden, p. 128. 1909. _ gigas Brady. Scott, pp. 24—25.

1904. — _ — Cleve, p. 196. IgI0. — nasutus Giesbr. Farran pp. 18—19.

1905. _ ts; — Farran, p. 30.

Description £9. The females examined varied in size from 4°5 to 5 mm. When this characteristic
species is examined in lateral view, a marked difference is observed between the different specimens in the
outline of the head; in some animals a distinct pointed eminence is seen just in front of the insertion
of the antennulae, in others the outline in more even as figured by Sars; the size of this eminence
is probably dependent upon the preservation of the animal and the position of the antennulae in the
moment of death. The structure of the limbs is scarcely different from Giesbrecht’s description.
In the exterior margin in the middle between Se I and II of the Re II~III in the first pair of legs
a small incision with a circular pore(?), through which a minute conical eminence projects, is seen
(glandular pore?). In the three last pair of legs I have not been able to find secretory pores with
certainty.

As seen in Sars’ figure the /abrum, which is widely removed from the insertion of the anten-
nulae, is saddle-shaped and by a median line divided into an anterior and a posterior division (fig. 4a).
On the oral surface of the labrum, on each side almost attaining the middle, a row of fairly
long stiff hairs are found in addition to six short stout setae, more alike granules, in the middle partly
fused with transverse groups, and two posterior groups of partly sickleshaped spines, between which
large group of stout teeth are found (cf. Pl. I fig. 4e).. The lamina labialis consists of a median and
two lateral divisions (fig. 4c). In front of this we have laterally an inwards convex series of fairly
long bristles; the inner longitudinal row is posteriorly represented by row of rather short spines or
granules and anteriorly with irregular group of similar spines. Behind the lamina labialis and between
the serrula 6-dentata the setae are arranged as figured. The lobus labialis possesses 4 longitudinal
series or groups of hairs, which posteriorly and inwards are fused into a big irregular group of hairs,
extending between the two lobi. ;

fg. Size: 38 to 445mm. The head is less produced in front of the rostral filaments. The ab-
domen, which is one fourth of the length of the anterior division consists of five somites; the first one
is dorsally and posteriorly produced into a distinct spine, corresponding to that found in the genital
somite of the female. The two first segments of the antennulae are well separated. The antennae
(cf. Pl. I fig. 4f) are more clumsy than those of the female, and so are the mandibulae, which have
a well developed manducatory lobe. The maxillulae, maxillae and maxillipeds, especially the
latter, which have the second basal segment scarcely twice instead of three times as long as wide, are
more clumsy than in the females, but scarcely less adapted for manducatory purposes. The mouth and
its surroundings are scarcely different from those of the female; the single specimen which I examined
had the spinulation of the labrum less coarse than in the female. The natatory legs are scarcely
different from those of the female. The internal sexual organs are found on the left side.

46 COPEPODA

Of this species Giesbrecht has only examined a single mutilated male from the Pacific Ocean.
The figure, which is represented on his pl. 9 fig. 14 is not quite like the structure found in several
males which I have examined, the main-differences being that the endopodite of the right leg in none
of my specimens is terminated with a short clumsy hair; it is rather doubtful if this difference has any
specific value, as the legs of the animals examined show marked variations in other respects. The
left leg consists of 2 basal segments and a fairly elongate exopodite (fig. 4g) produced into a more or
less curved terminal spine and a minute Se; only in a single one of my specimens, which had no Se, the
St was so strongly curved as figured by Giesbrecht (fig. 4h). In the four specimens examined the
exopodite of the right leg had a long St and a short slender Se; but the endopodite varied in a
curious way. In a specimen (fig. 4g) with the Ri about 5 times as long as wide, the articular line
between the last two segments was almost obsolete, and the posterior surface was more hairy than in
the specimen with the segment about 36 as long as wide (fig. 4h). In a single specimen (fig. 4j) the
Ri was represented by short segment, but this is probably due to a mutilation.

Y. 9—d (St. V). Size: 35—41 mm. The “head” is about twice as long as the thorax, and the
anterior division is 5°5 as long as the abdomen, which consists of four somites; the last one is partly
fused with the furca; the first (genital) somite is produced beneath in the female, not in the male.
The appendages are in most respects alike those of the mature females; the only difference of any
interest is, that the exopodite of the maxillulae possesses 8 instead of g bristles. While the fifth pair
of legs in the female is like that of the mature, this organ is in the male less developed than in the
full-grown animal. The left leg (fig. 4k) is most similar to that of the female, but less slender; the Ri
is represented by a conical protuberance, and a minute Se is found in Re. The right leg possesses an
exopodite very similar to that of the left leg, and a fairly long and slender endopodite with a slender
terminal bristle. Brady gives (Pl. VIII, fig. 10) in his description of RA. gigas, without having under-
stood its real nature, a figure of the fifth pair of legs in the young male; the Ri dext. has two bristles
in stead of a single one, and the Se of Re is missing; in the former feature a valuable character between
the yd of the two species is probably found; the latter character is probably due to a mistake (or an
abnormity) as an exterior seta is present even in the mature female of Brady’s species (Pl. VIII fig. 9)

as well as in Rh. grandis Giesbr. in contrast to the female of Rx. nasutus.

Y.9—¢ (St. IV). Size: 39mm. This stage is characterized by the three somites of the urosome.
The pes V is better developed in the male; the right and the left legs are as shown in fig. 41 nearly
symmetric. The Ri sin. is longer than in the preceding stage, but shorter than the Ri dext, which is

however shorter than the Re dext.

Variation. A mature female (Thor St. 72; fig. 4b) had the lateral thoracic spine on right side
of fourth thoracic somite distinctly bifurcate (in the same specimen a nematode was dwelling as para-
site); a corresponding variation was found in a specimen from Thor St. 183, but in addition the right
dorsal spine of the first abdominal somite was bifurcate. In a mature female from Thor St. 82 the
latter abnormity was found on both sides and in a young female on the left side only. In a single
specimen (Thor St. 88) the Re of the right fifth foot has a lateral pointed projection (fig. 4d); about

the variations in the fifth pair of legs in the males I refer to the description of the male.

COPEPODA 47

Parasitism. In several specimens the body cavity. was partly filled with a nematod, which
was very distinct through the skin on account of its white colour; this parasite was observed in a young
female from. Thor St. 153, in 5 £2 from St. 183 and in one from St. 82, and mag. sci. Hj. Ditlevsen
has kindly informed me that it is a larval stage, the exact determination of which is impossible on

account of bad conservation.

Occurrence. The Ingolf Expedition has collected this species at the following stations south
of Iceland.

7/6 95 St. 18 61°44 L. N. 30°29 L. W. V'.200—o fm. Temp. at the surface 10°C. 39.

8/. 96 St. 54 63°08 L. N. 15°40 L. W. V'.100—o fm. Temp. at the surface 9°C. 69.

13/, 96 St. 49 62°07 I. N. 15°07 L. W. V*.100--o fm. Temp. at the surface 93°C. 49.

12/, 96 St. 47 61°32 L. N. 13°40L. W. V. 1too—ofm. Temp. at the surface 10°C. 1 y? (V).
5/, 96 St. 52 63°57 L. N. 13°32 L. W. V‘'.200—ofm. Temp. at the surface 83°C. 2 £9.

20/, 96 St.57 63°37 L. N. 13°02 L. W. V. 10o—ofm. Temp. at the stirface 82°C. 9 £2 1f¢.
/, 96 St. 45 61°32 L. N. 9°43 L. W. V. 100—ofm. Temp. at the surface 95°C. 1 f9.

The Thor Expedition has taken this species at about 12 stations in the Atlantic south and
south-east of Iceland. Only at the following 6 stations more than single specimens (generally adult

females) were found.

Thor 9/, 1904 St. 178 63°08 L. N. 21°30 L. W. Yt. 750. M. Wire 16 f9.
/, r904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 150f2; rfid; 2yQ(V) 2 yh (V).
24/; 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 25 £2; 8 y2(V); r yo (V).
23/; 1904 St. 102 61°41 L. N. 13°31 L. W. Yt. 15 M. Wire 20f9; 2 y? (IV).
22/. 1904 St. 100 61°21 L. N. 10°39 L. W. Yt. 15 M. Wire 20f9; 8 y (V).
™/, 1904 St.124 61°04 L. N. 4°33 L. W. Yt. 1000 M. Wire 50f92; 10 y?(V) 3 yo (V).

In Denmark Strait the Ingolf did not take any specimens, but the Thor brought it home from

the following stations.

Thor 79/5 1904 St. 153 65°20 L. N. 27°12'5 L. W. Yt. 1000 M. Wire 36 £9; 5 y?(V).
21/6 1904 St. 154 65°27 L. N. 27°10 L. W. Yt. 800M. Wire 6 f9.
75 M. Wire 5 £9; ty?(V); 1yd (V).
50 M. Wire 1 f92; 1 y?.
8/6 1904 St. 150 65°50 L. N. 26°53 L. W. Yt. 4oo M. Wire 2 f9.

The Thor has outside the Ingolf area south-west of the Feroes caught the species at the

following stations.

Thor '5/g 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 8 f9; 1 y?(V). :
Yt. 800 M. Wire 35 £2; 6£4; 7oyd; 25yc (V).
"ly 1905 St. 167 57°36 L. N. 9°55 L. W. Yt. 1500 M. Wire 20 f9.
300 M. Wire 2 f9.
200 M. Wire rid

48 COPEPODA

8/6 1905 St. 72 57°52 L. N. 9°53 L. W. Yt. 1500 M. Wire 50 f?; 5 £4; 20 y2(V); 20y dh (V); 1 yd (IV).
20/5 1905 St. 88 48°09 L. N. 8°30 L. W. Yt. 300 M. Wire 75 £9; 60f¢; 15 y?(V); 5 yo (V).

21/, 1905 St.go 47°47 L. N. 8°00 L. W. Yt. 300 M. Wire 10 £9; 10 fd; 1 y? (V); 2ych (V).

7/, 1904 St. 11.959°54 L. N. 4°00 L. W. Yt. 500 M. Wire 1 y? (V).

From the material available it has been impossible to form any conclusive opinion about the
season at which Rhincalanus nasutus attains its full development. By counting the specimens, col-
lected by the Thor Expedition with the young fish trawl from May, June and July 1904 and 1905, I
have attained the following figures. Even if we admit that the animals have been taken in two suc-
ceeding years in a limited and occasional quantity, I think that the following figures give some im-
pression of the relation between the males and females etc. About roo f?, 20 y@ and a few young
males were taken in the month of May 1904 between 62°47 L. N. 15°05 L. W. and 61°15 L. N. 9°35
IL. W. In June 1905 about 150f?, about 80f¢, about 105 y? and 50 yo were taken between 57°52 L. N.
and 47°47 L. N., 9°53 L. W. and 8°06 L. W. In July 1904 (61°30 L. N. 17°08 L. W.) a single sample
containing 150 f9, rfd, 2yQ and 2 yd was taken. '/, 1904 (62°49 L. N. 18°46 L. W. Yt. soo M. W.)
5 females were captured. As the greatest number of males (60) against 75 females, of which three carried
spermatophores attached to the genital somite, were taken 2°/g 1905 St. 88 48°09 L. N. 8°30 L. W. Yt.
300—0, propagation probably took place in this locality.

Distribution. This species has been recorded from the Pacific between the Straits of Magellan
and the Gulf of California, from the western part of the Mediterranean and from the Indian Ocean
(one specimen only). Our knowledge about its distribution in the greater part of the Atlantic is very
scarce: “As far as concerns its distribution in the N. KE. Atlantic, it may be regarded as an inhabitant
of the Atlantic current; its distribution to the north and east depending on the varying strength of
that stream” (Farran p. 65). I think, that its occurrence on the west coast of Ireland, the Faeroe
channel, the Faeroe-Iceland channel, the North Sea south and south-east of Shetland, the Norwegian
Sea east of the Faeroes and east of Iceland (Sars), as well as at my own localities the south and west
of Iceland is easily explained in this way.

The vertical range of the species seems to be uniform from the surface down to more than
1800 meters (Farran p. 66).

Esterly (1912 pp. 317—318) has on a somewhat scanty material drawn the conclusion that
there is indication “of a movement of the greater proportion of the individuals from the neighbour-

hood of 200 fathoms upwards to above 100 fathoms at night”.

6. Eucalanus elongatus Dana.
(Pl. I figs. 5 a—d; text-figs. 9 a—f).

1852. Calanus elongatus n. sp., Dana. 1898. Eucalanus elongatus Dana. Aurivillius, p. 29.

1877.. Eucalanus elongatus Dana. Streets, p. 139. IgOI. — _ — Cleve, p. 6.

1892. — — — Giesbrecht, pp. 131, 149. 1903. va: = — J.C Thompson, p. 15.
1894. _ spinifer n. sp. Scott, p. 29, pl. I, figs.15—23. | 1904. — — — Wolfenden, p. 127.

1895. — elongatus Dana. Giesbrecht, p- 248. 1904. -- Atlanticus n. sp. Wolfenden, pp. 113—114,

1898. — - — Giesbrecht & Schmeil, p. 20. pl. IX, figs. 3—4.

COPEPODA 49

1905. Eucalanus elongatus Dana. Esterly, p. 131—132, figs. | 1908. Eucalanus elongatus Dana. v. Bremen, p. 15, fig. 10.

6a—d. 1908. _ a — Farran, p. 21.
1905. — _ — Th. Scott, p. 222. | 1908, = —_ — Wolfenden, p. 29.
1905. — — — Farran, p. 30. | IgIo. — - — Farran, pp. 93—94, pl.XIV.
1906. ee —_ — Pearson, pp. 6—7. IgIl. — — — Wolfenden, p. 204.
1906. _ —_ — G. O. Sars, p. 2.

Description. £9. Size: 65 mm. The females scarcely differ from Giesbrecht’s description.
No glandular pores were observed in the natatory limbs.

The dabrum proper, which is suddenly raised from the region lying in front of it, is by a
transverse groove divided into an anterior and a more raised posterior portion; the latter is divided
into three hairy lobes, a median and two lateral ones a | ¢
(text-fig. ga). The oral surface (fig. 5 a) shows a structure
similar to that found in Rhzzcalanus, but the two first
groups of the longitudinal series consist of fairly long and
slender bristles. In front of as well as behind the transverse

bar the skin is beset with a dense group of strong granules.
In front of the trebly divided /amina labialis (fig. 5 b) a.

median longitudinal row of long and a lateral one of very

delicate setae are observed; in the middle a row of very os)

short hairs is found on each side, single behind and \ y i
double in front. Between the serrulae 6-dentatae a longi- > | s (=
tudinal lateral series, a median group and more posteriorly a S uf

transverse group of short setae are found; behind the serrula

me
e
*

an oblique group was seen. The area labialis possesses a Text-fig. 9. Zucalanns elongatus Dana.

a. (to the left above) £0. Labrum etc. < 18.
b. £2. Abdomen X 18.
; : c c. (to the right) fo. Labrum etc. x 18.
continued on the latter, which bear four fairly regular a dr ikdamees ye x8.
; e. YQ (St. V). Abdomen x 18.
rows of hairs. £. (to the right beneath). Yo (St. V) X 18.

fg. Size: 45—5 mm. The fifth thoracic somite is better marked out, and the lateral corner is

central group of hairs between the labial lobes, partly

less produced than in the female. The head is in front of the transverse groove more strongly convex
(text-fig. 9c) and the labrum is lower; its oral surface is smooth; the labial appendages are lower.
The intestine is well developed with the usual convexity and coecal sacs.

The oral appendages are, as shown by Giesbrecht, greatly reduced. The legs of the fifth
pair (fig. 5c) are more slender than figured by Giesbrecht; the left leg was, except in two spec-
imens, the longer. In a single male the terminal segments of the fifth pair possessed a small median
hair in addition to the terminal one. The fifth pair of the young male has the left leg a little longer
than the right; the Re is divided into two distinct segments, of which the latter bears two long
bristles (fig. 5 f, cl. Wolfenden Pl. IX, fig. 3); in a single young? male the number of setae in the
terminal segment was 3 instead of 2 (fig. 5 d) and in another young (?) male the structure was, as seen
in fig. 5 e, more like that of the mature male. -

J2 (V). Size: 4455 mm. The lateral corner of the last thoracic somite is like that of the f¢.

The urosome consists of three somites, as the two basal ones (text-fig. 9 e) are fused in most specimens
The Ingolf-Expedition. III. 4. 7

50 COPEPODA

and slightly produced below. The anal somite is fused with the furcal rami, of which sometimes the
left and sometimes the right is the longer. The structure of the legs and of the labrum is scarcely
different from that of the female.

Jd (V). The male of this stage is scarcely different from the female except for the four
abdominal somites (text-fig. 9 f) and well developed fifth pair of legs, as previously described. Wol-
fenden (1904 p. 113) has, with some doubt established the young male of this species as a new one
Euc. atlanticus, because “the larger furcal segment and longest tail seta are on the left side, instead
of the right side”, and on account of the not retrograded oral organs.

As, however, the former assumption is wrong, because not only males and females but also
young specimens have the longest furcal branch now on the right and now on the left side, and as
the latter is a general phenomenon in the young males, the species must vanish.

J? (IV). Size: 38mm. In general structure this stage is like the preceding one, but the urosome
consists of 3 somites, of which the two first are of almost equal length and distinctly shorter than
the third one, which is fused with the furcal rami, on the left side being the longer in both specimens
examined. The ovaries were well developed though less so than in the preceding stage.

Occurrence. The Ingolf has taken this species only at a single station in Denmark Strait.

27/6 1896 St.95 65°14 Lat. N. 30°39 Long. W. V.200—o fm. Temp. at surface Se iltes 10 £9.

By the Thor it has been taken at the following stations.

Thor "9/6 1904. St. 152. 65°00 Lat. N. 28°10 Long. W. Yt. 1000 M. Wire 35 f9; 1 yh (V).

Yor? go f2.
20/6 1904. St. 153. 65°20 Lat. N. 27°12'5 Long. W. Yt. 800 M. Wire 1 f9.
21/6 1904. St. 154. 65°27 Lat. N. 27°10 Long. W. Yt. 800 M. Wire 30 f9.
Yt. 75 M. Wire 10 f9.
18/5 1904. St. 150. 65°50 Lat. N. 26°53 Long. W. Yt. 400 M. Wire 3 f9.

The Ingolf, in the Atlantic south of Iceland, has caught the species at 6 stations, and the

Thor at 7 stations.

Ingolf 17/5 1895. St.18 61°44 L. N. 30°29 L. W. V!200—o fm. Temp. at surface. 10°C. 15 f?

10/, 1895. St. 17. 62°49 L.N. 26°55 L.W. V'200—0 fm. — - — og1°C rf?
3/6 1896. St.68. 62°06L.N. 22°30 L.W. Virtoo—-ofm. — - — 87°C. 1f?
8/, 1896. St.54. 63°08 L.N. 15°40 L.W. V.100-ofm. — - — g0°C. 10 f?
13/, 1896. St. 49. 62°07 L.N. 15°07 L.W. V. 100—o fm. — - — 93°C. 4o ff.
12/, 1896. St. 47. 61°32 L.N. 13°40 L.W. V.100-o fm. — - — 106°C. 35 f9.
Thor 9/, 1904. St. 178 63°08 L. N. 21°30 L. W. Yt. 700 M. Wire 85 f2.
14/, 1903. St. 167. 63°05 L. N. 20°07 L. W. 1 9.
to/, 1904. St. 180. 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 8 f2.
t/, 1904. St. 285. 62°49 L. N. 18°46 L.,.W. Yt. 500 M. Wire 8 f9.
™/, 1904. St. 183. 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire about 350 f.
2/, 1904. St. 286. 61°49 L.N. 14°11 L. W. Yt. 1800 M. Wire 10 f9.

Yt. 15 M. Wire I f?.

COPEPODA 51

In the Iceland-Feroe channel, the Ingolf has taken it at 3 stations and the Thor at 6 stations,
one from the month of July with a single female, and 5 from May.

Ingolf 15/; 1896. St.52. 63°57 L.N. 13°32 L. W. V.t 200—ofm. 83°C. 2 9.
20/, 1896. St.57. 63°37 L.N. 13°02 L. W. V.‘ 100—ofm. 82°C. 9 f9.
™/, 1896. St.45. 61°32 L.N. 9°43 L.W. V.t 100o—ofm. g1° C. 15 ff.

Thor 73/; 1904. St. 102. 61°41 L. N. 13°31 L. W. Yt. 15 M.Wire too f9.

22/, 1904. St.100. 61°21 L. N. 10°39 L. W. Yt. 180 M.Wire 15 f9.
Yt. 15M. Wire 20 f9.
22/, 1904. St.g9. 61°15 L.N. 9°35 L.W. Yt.1000M.Wire 75 f?; 1 y?.

In the Atlantic outside the Ingolf area a big number of specimens, males as well as females,
were found.

Thor ‘3/, 1905. St.82. 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 5002; 28 y? (V); 100 yd' (V);
2 y? (IV).
Yt. 800M.Wire 50f?; 10 y?(V); 10 yh (V);
2 y? (IV).
/, 1905. St. 167. 57°36 L.N. 9°55 L.W. Yt. 1500M.Wire 25 f2; 1 yo (V).
8/6 1905. St.72. 57°52L.N. 9°53 L.W. Yt. 1500M.Wire 29; 12 fo; 15 y9(V); 16
yd (V); ry (LV).
20/6 1905. St.88. 48°00 L.N. 8°30L.W. Yt. 300M.Wire 35 £9; 3 fd; 1 y?(V); ryd
(V); 2 yo (IV).
2t/s 1905. St.90? 47°47L.N. 8°00 L.W. Yt. 300M. Wire 45 £9; 17 fd; gy2(V); 5
yd (V).
It is rather curious that a large number of adult females, but only three young animals, from
three stations, were taken in the numerous samples brought home by the Ingolf and Thor from 3*/,
—/, north of 61° Lat. North. At four southern stations (°/s—*"/s 1905) the Thor gathered mature males
and young animals in addition to numerous adult females.

Distribution. This species has been recorded from the Mediterrenean, the Indian Ocean, the
Pacific between 61° Lat. N. and 33° Lat. S., and the North and South Atlantic (as far south as 47°
Lat. S. 40° Long W.).

In the North Atlantic (cf Farran Pl. XIV) it has been found on the south and west coast
of Ireland, in the Feroe channel, north and east of Shetland and occasionally in the North Sea as far
east as the coast of Norway. “In point of number it is generally scarce. Vertically it is recorded
from the surface down to 4000 meters.” Esterly (1912 pp. 295—300) has on an extensive material

made it probable “that the species. is more abundant and more frequent above 50 fathoms by night
than by day.”

52 : COPEPODA

7. Eucalanus Attenuatus? Dana.
(Pl. I figs. 6a—c; text-figs. 10 a—e).

1849. Calanus attenuatus n. sp. Dana. 1903. Eucalanus attenuatus Dana. J. C. Thompson, p. 15.
Eucalanus attenuatus Dana. Dana. 1905. —_ — — Wolfenden, p. 996.
1892. a= — — Giesbrecht, pp. 131. 1905. a a — G, O. Sars, p. 2.
1894. = _— — Th. Scott, pp. 28—29. 1905. — _— — Esterly, p. 133, figs. 7a—c.
1895. a _ — Giesbrecht, p. 248. 1906. oa — — Pearson, p. 7.
1898. — — — Giesbrecht & Schmeil, pp. | 1908. _ a — Farran, p. 22.
20—21. 1908, —_ _ — v. Bremen, p. 16, fig. 12.
IgOI. _— _ = Cleve, p..6. 1909. _ — — — O. Pesta, p. 21.
1903. _— _— — Norman, p. 135. IgII. _ _— — —Q.-Pesta, -p. ‘20,
1903. — — —.° Cleve, p. 362: IgI0. _ - — Steuer, p. 21.
1900, -- - — Wheeler, p. 167. IgI2. — — — Sewell, p. 357.
1903. — — — J.C.Thompson & A. Scott,
pp. 242.

Description y?. (Stage V). Length: anterior division 3:34 -+- 1:26 = 46; urosome 0°58; total
length 518mm. The head (text-figs. 10 a—b) is like that of Riincalanus nasutus triangularly produced in

2 ° ‘ lateral as well as in dorsal view. The “7th thoracic somite (text-fig.
10 c—d) is fairly well marked out, especially dorsally, and its lateral
corners are slightly produced and rounded. The vostra/ filaments
(text-fig. roe) are long and slender, and placed on a long bifurcate
basal portion. The wrvosome, which is scarcely one sixth as long as
the anterior portion, consists of three somites. The first (I~ II), which
does not show any trace of receptacula seminis, is longer than the
two following combined; the fourth somite is completely fused with
the furca, which has the longer branch on the left side. The St. 2
sin. is distinctly longer and more powerful than the other setae.

The structure of the mouth appendages and natatory legs

scarcely shows differences of any importance from Giesbrecht’s

description; the Ri2 of the maxillipeds has only 3 instead of 4 Si.

Text-fig. 10.

No glandular pores were observed in the four pair of legs.
Eucalanus attenuatus Dana. YQ (stage V). . i
a. Head in lateral view x 18. The /abrum is in lateral view like that of Zuc. elongatus

b. Head in dorsal view 18. ‘

c.—d. Abdomen in lateral and dorsal though less produced. The oral surface differs from that of the other
view X 18. ‘ : F :

e. Rostral filaments < 27. species 1) by anterior group of minute spines laterally near free

margin, and 2) by the different number and arrangement of three first groups of spines in longitudinal
series, as seen by comparing figures 5a and 6a; the structure of the three posterior groups and of the
transverse rows are scarcely different from that of Awe. elongatws. About the small differences existing
in the structure of the labium etc. I refer to fig. 6b.

Yd (Stage V). Length: 5mm. The lateral corner of the fifth thoracic somite is less produced.
The urosome consists of four somites, of which the first one is 1:2 as long as the second, which is
again 1'3 as long as the third and fourth. In this species the fifth pair of legs (fig. 6c) shows, as a
whole, more similarity to that of the adult male of Z attenuatus than in &. elongatus. The right leg

is the shorter, and the segments are more attenuated than in the mature male.

ee en eee ee eee

COPEPODA 53

Remarks. Most probably the specimens examined ought to be referred to Luc. attenwatus Dana
in spite of a more produced forehead than in original specimens, and of greater size (Giesbrecht f9:
42—4°85 mm.). The Thor Expedition has taken the species at the following two stations

m/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire ry?; 1yd.
8/5 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 1yé.

Eucalanus attenuatus has been recorded from the Pacific, the Mediterranean, the Indian Ocean
and the Atlantic. In the North Atlantic on the west coast of Ireland it has been found as far north
as 54°57 Lat. N. 10°51 L. W. at about 700 fathoms.

8. Eucalanus crassus Giesbrecht.
(Pl. I fig. 7; textfig. rz).

1888. Eucalanus crassus n, sp. Giesbrecht, p. 333. 1905. Eucalanns crassus Giesbr. Th. Scott, p. 222.

1892. — — Giesbr. Giesbrecht, p. 132, pls 4. 11, 35. | 1905. a — — G.O. Sars, p. 2.

1898. _ — _— Giesbrecht & Schmeil, p. 22. 1905. _ _ — Esterly, p. 134, fig. 8.

IgOI. _ _ — Cleve, p. 6. 1905. | — -— — Farran, p. 30.

1902. — — -- Wolfenden, p. 361. 1906, — = — Pearson, p. 7.

1903. _ _ — J.C. Thompson and A. Scott, | 1908. _— — — v. Bremen, pp. 16—17; fig. 13.
p. 242. 1908. — _ — _ Farran, p. 22.

1903. — — .— Cleve, p. 362. 1909, — _— — A. Scott, p. 1I9g—20.

1904. an _ — Wolfenden, pp. 127—128, IgI2. — —- — Sewell, p. 357.

1905. — _ — Wolfenden, p. 996.

Description. f?. Length: 3°7—40 mm. The basal fused portion of the rostral filaments is com-
paratively longer than figured by Giesbrecht (t. 35, fig. 26). The last thoracic somite, which is well
marked out, is somewhat rounded (text-fig. 11). The adomen consists of 3 somites only; the receptaculum
seminis is large. The coecal sacs on each side are divided into smaller parts (fig. 7). In the
structure of the appendages a feature of interest was observed in the structure of the
external process of the basal segment of Ri, pes I, which is produced into a distinct fay
point not seen in Giesbrechts fig. 29 taf. 11. No glandular pore was observed.

The /abrum is, in appearance, like that of Hucal. elongatus, but the distance
to the insertion of the antennulae is comparatively shorter, and by a transverse groove
divided into an anterior and a posterior better raised part. The oral surface of the

labrum is most like that of Zuc. attenwatus, but differs somewhat by sharp distinction
Text-fig. 11.

between median and lateral groups of marginal bristles. The two first groups of the zy-ozanus crassus

longitudinal series are partly fused and convex towards the middle. Around the first Giesbr. £9. Ab-
f : domen in lateral
muscular spot a transverse group of granules is seen. The structures of the labium view x 30.
are in the main similar to those of the species mentioned.
Occurrence. The Ingolf Expedition has not taken this species, but it probably belongs to the

area, as the Thor Expedition has taken it at

20/3 1905 48°05 Lat. North 8°29 Long. West Yt. 300 M. Wire 1 f9.
3t/s 1905 St. 167 57°46 Lat. North 9°55 Long. West Yt. 1500 M. Wire 3 f?.

54 COPEPODA

Distribution. This species has been recorded from the Mediterranean, the Indian Ocean, the
Pacific and the Atlantic. It has been found several times in the Feeroe channel and on the west
coast of Ireland as far north as 56°rr L. N. 9°50 L. W.

Paracalanidae.

g. Paracalanus parvus Claus.
(Text-figures 12a—f).

1863. Calanus parvus n.sp. Claus, p. 173. 1903. Paracalanus parvus Claus. J.C.Thompson & A. Scott, p. 243.
1864. Paracalanus parvus Claus. Boeck, p. 233. 1903. — — -— Cleve, p. 367.
1892. _ — — Canu, p. 169, pl. I, figs.1—12. | 1904. _ —_ — Cleve, p. 194.
1892. oa — — Giesbrecht, pp. 164—171, taf. | 1904. - — — Wolfenden, pp. 129—130.

I, 6 and 9. 1905. — -- — var. borealis n. var. Wolfenden,
1894? ~ = — Th. Scott, pp. 26—27, pl. I pp. 997-998, pl. 96 figs 7—11 and 16.

figs. 9—14. 1905. _ parvus Claus. G. O. Sars, p. 2.
1898. — _ — Aurivillius, pp. 29—30. = _ — Farran, p. 30.
1898. _— — Giesbrecht & Schmeil, p. 24. os — — Esterly, pp. 140—41, figs 12a—e.
1899. _— - — Th. Scott, p. 248. 1906, _ = — var. perplexus n. var. Norman
1899. = - — Brady, p. 32. & A. Scott, p.127 pl. XII figs. 1—2.
Ig00. _ — — Th. Scott, p. 383. 1906. _ parvus Claus. Pearson; p. 8.
1900. = aa — Wheeler, p. 168, figs 6a—c. 1906. — - — T.Scott, p. 298.
19OI. — — — Th. Scott, p. 350. 1908. _ — — vy. Bremen, p. 20 fig. 17.
Igor. a — — Cleve, p.8. 1908. _— _— — Farran, p. 22.
IgOl. a= — — Brady, p.32. 1909. - — — A. Scott, pp. 27—28.
1902. _ — — A.Scott, p. 402. IgIo, _ —~- — _ Farran, pp. 61—63.
1902. i — — Wolfenden, p. 361. IgI0. — — — Kraeeft, p. 77, taf. 1 figs.
1902. — _ — G.O.Sars, pp. 17—18 pls VIII I—I3.

° —IX. IgI0O. — - — Steuer, p. 22.
1903. — — — Jensen, Johansen and Levin- | 1912. — _ — Sewell, p. 358.
sen, p. 303, tabel I.

Description. £9. Size: 0'84—1°0 mm.

In contrast to Giesbrecht the head and the first thoracic somite are completely fused. The
mouthlimbs are scarcely different from Giesbrecht’s description. In the structure of the natatory
legs, however, fairly well marked differences are found, especially in the armatures of the basipodites
and endopodites; in these respects they fairly well agree with Sars’ description, but especially with
that given by Wolfenden for his P. parvus variet. borealis. In Sars figure, Pl. IX, the first segment
of the exopodite of the first pair of legs has a minute spine; in all my specimens this spine is sub-
stituted for by a bundle of fine hairs as seen in Giesbrecht’s Taf. g fig. 31. Glandular pores are ob-
served at the base of the exterior spines of the exopodites (at least in the second pair of legs).

Between the mouth and the rostral filaments the usual elevations are found; I was not able
to see any setae along the hinder margin of the labrum. The arrangement of hairs on the oral sur-
face of the labrum is similar to that of Pseudocalanus. The first group, which is convex outwards,
and oblique, consists of about ro short hairs in a single row; this group is followed by an almost
straight row of about 25 very short hairs; most orally, and fairly well separated from this group, 20
hairs are placed in a S-shaped group. Laterally to the first group two partly transverse groups of

COPEPODA 55

fairly long setae, slightly convex inwards and posteriorly, are found. The median circular spots and
transverse series of hairs were not observed. The lamina labialis shows three serrations, of which
the median is the smallest. The serrulda 6-dentata is found as usually; the arrangement of the setae
was not examined in detail.

fg. About the description of the mature males I refer to Sars and Giesbrecht. Size: o7
—1'02 mm.

YQ—¢ (St.V). Size: gf o80 mm, (O. Exp. 1900); 2 (0°61 4- 0118) = 079 mm. (Ingolf 96 Cyl. 45).
The shape of the body is in the main like that of the mature female, but the head and the first

thoracic somite are fairly well separated, b ;

and there is an indication of limitation § -

between fourth and fifth thoracic somite. fess a
The first abdominal somite is, at least in | as)
most specimens, distinctly produced below i

(text-fig. 12 b). The oral appendages are q a |
scarcely different from those of the mature hi

females; the natatory legs, however, show a ‘ ! oper
few differences; a very short Se Re II is if “A g

=
ey
a

present in the first pair of legs. The ex-

terior margin of the last segment of exo- (7
podite is smooth in the fourth pair of legs, Reeves ea see meene parva Cate,
q Bie j a. £9. Genital somite in lateral view X 90.
but, as usual, dentated in the third pair. b. yQ (Stage V). Abdomen x 90.
‘ ‘ K c. yd (Stage V). Abdomen X go.
The fifth pair of legs appears more clumsy Sao ae Vi. i aiatiow view. X ¢. 400s

with shorter terminal spine. e—f. yQ—c (Stage IV). Abdomen X go.

P . £9. Ab 1 i ith well developed Vv :
The male differs from the female Reet tet Nee SEVERED PFS ¥1X 99
by the less prominent first abdominal somite, and by the better developed asymmetrical fourth pair

of legs (cf. Canu) (textfigs. 12c—d).

YQ—d (St. IV). Size: (048 +014) = 062mm. This stage is easily distinguished from the pre-
ceding one by the number of abdominal somites (3 only). Asin the other stage, differences are found
in the less prominent fifth pair of legs in the males (cf. text-figs. 12 e—f).

Of the copepodites (stages I—III) I am not sure of having observed any; according to Oberg
these as well as the larval forms are rather difficult to distinguish from those of Pseudocalanus elon-
gatus; they are, however, smaller and more clumsy, and have the exopodite and the endopodites of the
antennae of almost equal length. From Ingolf St. 62 (Apst. 14) I have examined a young specimen
(St. II) o6 mm. long and one (St. I) 0-48 mm. long, which on account of the long endopodite of the
antenna perhaps ought to be referred to this species.

Variation. In a single mature female? (F. 389 ©. Exp. 1900), the size of which was (0°68 + 02)
= o88 mm. the left leg of the fifth pair consisted of four segments as in the immature male, while the
right consisted of two segments only, A somewhat smaller female from the same locality had both pair
of usual structure. Bay has taken 3 specimens with the left leg somewhat longer than the right,

56 COPEPODA

though consisting of the same number of segments. Normann & Scott have with reservation described
a female with the right fifth foot three-segmented, and longer than the left as P. g. var. perplexus.

Remarks. The specimens, which have been examined all belong to the northern variety (var.
borealis Wolfenden p. 997), and are fairly well distinguished from the Mediterranean form described by
Giesbrecht. A. Scott (1909 pp. 27—28) thinks that the differences are rather unimportant, in that
he is scarcely right. Detailed examination of a good many specimens from different localities especially
from the Mid-Atlantic is necessary to decide the question whether the observed differences are specific

or due other reasons.

Occurrence. The Ingolf Expedition has taken this species from 7 stations to the south and
south-east of Iceland as well as in the Feeroe channel. It has been taken as far west as at St. 84 —
Long. W. 25°24, Lat. N. 62°58; the only station farther north where is has been taken by the Ingolf
Exp. is St. 101 (Apst. 47 9/, 1896 4 p.m. 66°23 Lat. N. 12°05 L. W. 2 £9) north-east of Iceland. From
the East Greenland Exp. 1900 it was once taken in Denmarks Strait as far north as 65°36 L. N. 31°32
L. W. 9/o 2 a.m. F. 318. The comparatively few other localities, in which it has been taken by this
Expedition lies between 62°06 Lat. N. and 59°20 L. N., and 21°11 L. W. and 0°52 L. W. At the fol-

lowing stations more than single specimens of this species were captured.

Ingolf 17/6 96 St. 84 62°58 L. N. 25°24 L. W. Cyl. 9 £9; 3 y? (V); 2 yo (IV).
19/3 95 61°02 L. N. o°4o L. W. Pl. x1 f2; 2yh (V).
17/3 96 60°28 L.N. o°20 L. E. Cyl. 9 £9; 1 £6; 3y2(V); ry ht (V); ry2(IV); ry gd (V).
@.Exp.190074/, 6 p.m. 61° LL. N. 16°26 L. W. F.389 2 £9; 2d; 6yP(V); 2yh (V).
5/,2 p.m. 60°29 L. N. 12°10 L. W. F.399 7 £9; 3 yo (V).
8 a.m. _ — F. 396 3 £2; 2 y? (V); 2yd (V).

It is an interesting fact that almost all the collections of this species are from the month of
September (O. Exp. 1900 9/,—3°/, 16 Stations) or from the month of August (Ingolf Exp. 1895—96
9/s—"7/g 8 Stations). In the month of May a single young male (4/, 96 Cyl. 2 57°54 Lat. N. 6°27 L. E.)
was taken, and in the month of July (Cyl. St. 84 "7/6 1896 62°58 Lat. N. 25°24 Long. W.) 9 mature
females, 3 young females (stage V) and 2 young males (stage IV) were taken. Young animals (St.
IV—V) were also captured as late as *7/s 1896 and 25/, 1900. The fact that this species was rarely
taken in several collections in the monthes of May and June 1895, 1896 and 1900 in the same regions
in which it was found in August and September indicates a certain periodicity in its occurrence, as
shown by Farran, in several of the localities explored by the International Investigations (1910 pp.
61—62). The average salinity for this species, which generally is swarming at the surface is rather
low in the Kattegat (19°33 °/oo, Temp. 10°33° C.), but a good deal higher in the English Channel (35°26 °/oo,
Temp. 13'28° C.). According to Cleve (igor) the salinity in the Arabian Gulf lies between 35°77 °/oo and
36°20 °/oo (Temp. 267 C.) and in 1904 between 35:40 and 40°70°/,.; the maximum temperature at which
it was found in the Indian Ocean is 29°35 C. (Cleve rgor p. 8).

Distribution. Assuming the specific identity of the northern and tropical forms we find records
of its occurrence from the Mediterranean, the Black Sea, the Red Sea, the Arabian Sea, the Indian
Ocean as far South as New Zealand (Brady rg1r p. 32), the Malay Archipelagos (A. Scott 1909) the

COPEPODA 57

Pacific between 61° N. and 52° N., between 10° S. and 55° S. west of South-America, and 108° L. W.
Equator (Giesbrecht 1892) and off California (Esterly 1905). In the North Atlantic it has been
recorded on the west side off Woods Hole (Wheeler 1900) and on the east from the Faeroes to Gibraltar.
According to Scott (1894) it is fairly common in the Gulf of Guinea as far south as the Congo;
Wolfenden shares, probably rightly, the opinion that the species which the mentioned author
describes as P. parvus really is Paracalanus aculeatus Giesbr. which represents this species in the
South Atlantic (1911, p. 203). In addition to all these localities this species is found in the southern
part of the Baltic, the Kattegat and the North Sea.

Pseudocalanidae.

10. Pseudocalanus minutus Kroyer.
(Plate I fig. 8; text-figs. 13 a—f and 14 a—c).

1845—47. Calanus minutus n.sp. Kroyer, T. 41 fig. 4. | 1903. Pseudocalanus elongatus Boeck. Jensen, Johansen, Le-
_ 1849. Calanus minutus Kr. Kroyer, pp. 543—44, 552. vinsen, p. 304, tabel II.
1864. Clausia elongata n.sp. Boeck, p. 234. - 1903. —_ — — J.C.Thompson &A. Scott,
1872. Pseudocalanus elongatus Boeck. Boeck, p. 37. : p- 244.
1892. _ —_ Boeck. Giesbrecht, pp. 197—200, | 1904. — — — Wolfenden, p. 111.
taf. Io, 1905. — — — G.O.Sars, p. 3.
1892. Clausia elongata Boeck. Canu, pp. 170—171; pl. II, figs. | 1905. — — — Farran, p. 30.
, I—1I3. 1906. —_— = — Pearson, p. Io.
1897. Pseudocalauus elongatus Boeck. Vanhéffen, p. 278, pl.I, | 1906. -- — — Williams, p. 640.
fig. 6. 1907. _ major G. O. Sars. Koefoed & Damas, p. 407.
1898. — +- — Giesbrecht & Schmeil, | 1907. — gracilis G.O. Sars. Koefoed& Damas, p. 406.
, p. 28. 1908. _ major G. O. Sars. v. Bremen, p. 25, fig. 22.
1898. _ -— — Aurivillius, pp. 69—7o0. 1908. — elongatus Boeck. v. Bremen, p. 25, fig. 23.
1900. ai _ — G.O.Sars, p. 69. _ = — Farran, p. 28.
1900. -— major n. sp. G. O. Sars, pp. 69—72, pl. XX. | 1910. = — — Oberg, pp. 48-49, 56-57
1gOI. _ elongatus Boeck. Th. & A. Scott, p. 339. taf. I and VI fig. 3.
1902. — —_— — Mrazek, pp. 507—508, — — — Kraeeft, pp. 67, 77. 79,
figs. 5-6. taf. I figs. 13—21.
1902. — —_ — Th. Scott, p. 450. IgIo. oa _ — Steuer, p. 22.
1902. — _ — Wolfenden, p. 361. IgIl. _ _ — Farran pp. 63—65.
1903. — — — Norman, p. 135. 1913. — — — Stephetisen, pp. 71—72,
1903. — — — 1.C Thompson, p. 16. ; pls 4—s.
1903. a — — G. O. Sars, pp. 20—21, | 1913. _ _— — Stephensen pp. 312—13.
; pls X—XI.
1903. —_ gracilis n. sp. G. O. Sars, pp. 154—155,
pl. I (Suppl).

Synonymy. As Kroyer has described and figured a young male of his species, it is perhaps
not so curious that the different authors have not realized that it is identical with Psewdocalanus elon-
gatus Boeck. Kroyer’s description and figure are however so good, that scarcely any other species from
the Arctic Sea has a pernultimate stage to be confounded with it. As I have had the opportunity of
examining Kroyer’s original specimens, it is quite evident to me, that the two species are identical;
the three examined specimens belonged all to the penultimate stage (1d6‘-+ 29); they were in the shape
of the head most alike Ps. gracilis, and were of middle size. According to the general rules of nomen-
clature the name Ps. clongatus ought to be changed to Ps. minutus Kr., if the three forms are referred
to a single species.

The Ingolf-Expedition. III. 4. 8

58 COPEPODA

Introductory Remarks. The material which I have examined of this species has been very
big, as it is one of the most abundant and widely distributed plancton-copepods of the northern seas;
it was therefore quite necessary for me to try to solve the question, whether different or only a single
species alike to Psewdocalanus minutus exist; unfortunately the result of my investigations is not quite
satisfactory. Sars has been the first, who has pointed out that different types exist, and taking the
scanty material into consideration he was quite right in establishing the three species Ps. elongatus
Boeck, Ps. major G.O.S. and Pseudocalanus gracilis G. O.S. No naturalist has later on tried to solve
the question, scarcely touched it'; most of them have examined specimens from southern regions and

ey

Text-fig. 13. Pseudocalanus minutus Kr.

have scarcely been wrong in
referring them to the Ps. elon-
gatus Boeck (sensu strictu).
According to Sars the 3 species
are characterized in the fol-
lowing manner.

1) Ps. major G. O. S. Aver-
age length of 2 24mm. The

head is only slightly produced
anteriorly; the abdomen is half
as long as the cephalothorax.

The antennulae extend almost
to the middle of the abdomen.

: : 2) Ps. elongatus Boeck (sens.

a. £0. Head from the left X 110. b--c. YQ—d¢ (stage V) Abdomen 59. strict... The average length
d. Yo (stage V) Pes V X I50. e. Yo (stage IV) Abdomen X 59. : :
f. Yo (stage IV) Pes V X 150. is 14mm. The head is only

slightly produced anteriorly; the urosome somewhat exceeding half the length of the anterior division.
The antennulae scarcely reach beyond the second caudal somite.

3) Bs. gracilis G.O.S. Average length 1°65 mm. The body is more slender and the head anteriorly
distinctly produced; the urosome scarcely exceeds half the length of the anterior division; the caudal
rami are comparatively narrower and more divergent. The antennulae reach to the end of the third
caudal somite. Legs considerably more slender than in the typical species, with both rami‘very narrow.

It will be noticed that in most characters, except in size, the Ps. gractlis differs almost equally
from the two other forms. The character found in the size and the length of the urosome is at
least of very relative value, as even from the same station (Ing. Nr. 31)? the following was observed:
Spec. Nr. r 2°3 mm. with ant. division 2°5 >< urosome, Nr.2 18mm. ant. div. 2°5 = uros. (head of
gracilis type); Nr. 3 18 mm. ant. div. 2 = uros. (head elong. type); Nr. 4 17 mm. ant. divis.
2°5 =< uros., Nr. 5 1°5 mm. ant. divis. 2.4 >< urosome; Nr. 6 1:4 mm. ant. divis. 2:1 = urosome; Nr. 7 1:2 mm.
ant. divis. 23 =< urosome. The relation between the length of the urosome and anterior portion has

t With the exception of Damas and Koefoed, who have often been in difficulty about the identification of the
specimens and p. 406 write “Ces deux espéces, distinguées par Sars, ne sont peut-étre que des variations d’une seule forme”.
2 N.B. from this station was found copepodite (St. V) 177mm. and cop. (St. IV) 14mm. long.

COPEPODA 59

also been examined at several other stations (f inst. Gunolfsvig Iceland), where I often found that the
small specimens had the urosome comparatively longer (f. inst. ant. div. 19 =< uros.), but with several
exceptions. According to Sars the anterior division of Ps. gracilis is comparatively more slender; I
found, certainly, that a specimen of typus mayor had the anterior division 2:3 as long as wide, one of
typus gracilis 2°7 as long as wide, and one of typus elongatus 24 as long as wide, but as several
exceptions were found, I was not able to use this character. I first got the impression that the
characters found in the comparatively long antennulae and natatory legs in several specimens of
the typus gracilis were useful, but a study of greater material made it evident to me that they
were too variable to be of any value. The feature which marks out some specimens as gracilis
is the curiously prominent forehead, which is in any case very seldom found in the biggest as
well as in the smaller specimens. But as all transitions were found between the different shape of
head, even in specimens which in other respects were most like gracilis, it was impossible for me to
accept more than a single species.

Description. f9?. I was not able with certainty to find any secretory pores in the natatory legs.

The /abrum proper, which is the most posterior of a row of more or less prominent elevations
found behind the insertion of the rostral filaments (text-fig. 13a), has along its hinder margin, on each
side, a group of fairly long hairs, and in the middle, somewhat in front, a hairy protuberance. ‘The oral
surface of the labrum possesses four groups of short hairs, as seen in fig. 8 (Pl. I). The lamina la-
bialis has along its posterior margin three indistinct rounded eminences; orally the two usual longitudinal
series of fairly short hairs are observed, of which the more lateral is longer and with longer hairs.
Behind the lamina a transverse row of short hairs or teeth is observed and a similar but longitudinal
one is found inside the serrula 6-dentata. Between the labial lobes, which are covered with hairs, the
arrangement of which were not made out, about four groups of hairs are found, of which the hind-
most, which has longer hairs, stands more laterally. Between this and the lateral margin behind the
labial lobes 2 oblique groups of hairs are present.

Behind the area labialis proper is found on each side a large group of fairly long hairs in addition
to a few hairs more laterally, and in the middle a triangular group, placed more posteriorly and with
its hindmost, wider part fused with a rather irregular group of setae placed between the insertion of
the maxillae.

f3. As far as the full-grown males, of which comparatively few were examined, were concerned,
I could not find other differences between the different specimens than that of size, varying from Ir
to 14mm. Canu and Sars have given descriptions and figures of the rudimentary mouth limbs. In most
specimens an indication between the head and first thoracic somites was seen as figured by Canu as
well for the male as for the immature specimens.

Y. (Stage IV). Size: r2—19 mm. The last thoracic somite is generally more produced than
that of the mature females, and dorsally a more or less marked limitation between the two last
somites is found (text-figs. 12b—c). The urosome is comparatively short and sometimes only one third
of the anterior division; according to Kraefft (figs. 15—18) the two first somites are better separated
in the males than in the females; generally no such differences were observed, but in some young

females, especially of the smaller “variety”, the two first somites were somewhat produced below,
8*

60 COPEPODA

probably an indication of the final ecdysis. The mouth limbs are scarcely different from those of
mature females. The males are always easily distinguished from the females by the presence of the
well developed pes V (text-fig. 13d) which consists of two basal segments and two terminal ones (Re),
which especially on the right side, are not always so well distinguished as figured by Canu (PI. II fig. 6).
In this stage varieties similar to those of mature females but less marked were found.

Y. (Stage IV). Size: og—1'4 mm. But for the presence of only 3 somites in the abdomen this
stage is like the preceding one, and shows similar differences between the two sexes (text-figs. 13 e—f).

Y. (Stage III). Size: o7—1o mm. This stage, of which Stephensen has given figures of
all the limbs, shows no sexual differences, and is characterized by four natatory legs and two abdo-
minal somites.

Y. (Stage II). Size. o5—o8 mm. This stage has three natatory legs and two abdominal
somites. The last copepodite stage as well as the larval forms was not with security found out; I
refer to Oberg’s description.

Variation. From Iceland I have examined a female (taken 5/5 1902 by Ditlevsen in Heste-
reyrifjorde) with a spermatophor attached to the genital somite, in which a fairly well developed

. b : fifth pair of legs was observed (cf. text-fig. 14 a—b).

The Ingolf Exp. (at St. 49 V.t 10o—o fm.) has taken

a full-grown female? alike the preceding but with

much longer pes V, of which the left is longer than

the right (text-fig. 14 c). The ©. Exp. 1900 (F. 451)

has taken a female with a right and left pes V of
\ almost equal length; the Re III of left pair is rounded

and short, without terminal seta; the corresponding
segment of the right side is more elongate. From

Ingolf (St. 29 V' 50—o fm.) I have examined a
Tent fia. Ui {teat semarint ie, spore seal, young animal (2?) with a rudimentary pair of legs,
a, Abdomen (female with spermatophor from Hestereyri- consisting of two short basal segments, and a rounded
fjord Iceland) >< 67. : ‘ -
b. Pes V of same specimen x 160. small terminal segment. Boeck is the first who
Silty Abe ate Peary st spectenen from Ing. See has mentioned females with a fifth pair of legs
(1864 p. 234), and Mrazek has published an interesting study on this topic. He has found a small
rudiment now and then, and sometimes a fairly well developed pair of legs; his figures of two spec-
imens are somewhat different from each other, but in structure mainly like my specimen from @.
Exp. Kraefft has examined a female with a rudimentary fifth pair of legs. It is interesting, though
in no way surprising, that the organ in none of the 6 specimens in which its structure has been
described was alike another.

Occurrence. This species has been taken almost all over the area explored by the Ingolf
Expedition, as far north as Jan Mayen and the Diskoisland; in the Atlantic it has not been taken
farther south than at the latitude of 63° North. By the East-Greenland Expedition it was only taken
at comparatively few stations, south east of the Feroes 61°06 Lat. N. 10°26 Long. W., in the Nor-

wegian Sea as far east as 1°04 Long. East (lat. 62°16 North) and at 6°12 Long. West (at 69°06 Lat.

COPEPODA 61

North), in the Polar Sea as far north as 72°30 Lat. North (6°41 Long. West), along the east coast of
Greenland as far north as c. 70° Lat. N. In Denmark Strait, in the Atlantic (west of the Feeroes)
and in the fjords of Iceland as well as on the west coast of Greenland it has been taken by several
collectors.

In the following I am going to give an account of the number of stations at which the diffe-

rent stages and partly the types of the species were taken at the different seasons.

West Greenland. In Davis Strait, on the west coast of Greenland, the Ingolf Expedition
1895, has taken mature females of Ps. mayor, at four stations from '/,—"/, 1895, Ls. gracilis at five
stations from *5/,—?8/,, and Ps. elongatus from a single stat. '/, Of the copepodites (St. V) specimens
of Ps. major have been taken at 2 stat. (2°/s—*/,), of Ps. gracilis at 3 st. (#/,—*°/,) and of Ps. elongatus
at 2 stat. (!/,—"/,); of the copepodites (St. IV) Ps. mayor was taken at 3 stat. (?°/s—"/,), of Ps. gracilis
at 2 stat. (°/,—*5/,) and Ps. elongatus at 2 stat. (*/,—"/,). At a single station ('/, St. 29, 65°17 Lat.
North 55°42 Long. West) a single mature male was found, but at no station copepod. of younger
stages than the fourth were taken. In contrast to the Ingolf Expedition, by which most specimens
“were taken in the open sea in vertical hauls in a depth of from 200--o fathoms, Bergendal and
Lundbeck have in 1890 taken a good many specimens at the surface and near the coast. On that
account, perhaps, almost all the specimens are most naturally referred to the Ps. elongatus type. From
“Jakobshavn” 2 mature males [from the same sample 50 f2; 5 y2(V); 4 yd (V); 3 yh (IV); 1 y (IID)
were taken 2°/s, mature females were taken at 3 stations (21/s—*8/s), young specimens (V) at same 3
stations and Ccep. (III—IV) at a single stat. (?8/s) only. From Egedesminde 2 mature males were taken
23/, [from same stat. 6 {2; 2y?2(V); 2yd (V)], 4/s 2ic [9 £2; 60 y2 (V); 35 yo (V) from same station] and
3 ig %°/s [from the same stat. 12 £2; 9 y?(V); 2 y2(V); 5 yd (V); r yh (IV); 1 y (III); 1 y (ID)]; from the
same locality mature females were found eight times between 21/, and 1°/g and a single time 9/,. night
[at this catch were taken 6 f9; 12 y2(V); 4 yo (V); 6 y2 (IV); 4 yh (CIV); 4y (IID); ry ID], young animals
(V) seven times between 3/, and '°/s and 9/;., young animals (IV) 3/,, 1°/g and 9/;, and Copep. (II—III)
only 9/;o.
At Disco Bay Lundbeck has °/, taken 160 mature females, 3 mature males, 3 young females
(V) and 5 males (V), 3 young females IV and 13 copepodites (III) and Bergendal at the same date
100 2? (VI), 1 df (VI) and 3 y? (V).

West of Iceland. In Denmark Strait and on the west coast of Iceland no specimens, which
were naturally referred to Ps. mayor, were observed; mature females of Ps. gracilis were only taken
at 3 stations (V.' 19-?0/; 1895) in the open sea and young ones (III—V) only '9/;, while specimens in
different stages, including mature males, of the Ps. elongatus s. s. were only found in “Dyrefjord” [3°/;
1895. 6 £2 (partly with egg-balls attached to genital somite), 9 y? (V), 2 y? (IV), rid, 7ydh (V), 1 yd
(IV), 2 y (III) and 3/6 1896 1 f9]. The sample from 19/; 1895 V.7 r00o—o. St. 8, 63°56 Lat. N. 24°40 L. W.
contained 100 f?, 2 y? (IV), 7 fd, 2 yh (V), t yP (IV) and 2 y (IV), and that from 7°/; 1895 V.! 100—o fm.
St. 9 17 £2 and 15 fo.

North of Iceland. In the fjords north-west and north of Iceland A. Ditlevsen has 25/s 1902, at
Hjalteneyri Ofjord gathered specimens of the elongatus type |1 £9, 2 y2 (V), 1 y2 (IV); 2 yh (IV); 1 y (III)|

62 COPEPODA

and 28/3 at Svavadilvig [2 f9, 1 y2(V); 1 yd (IV), 3 yd (V)]. Lundbeck has 25/; 1892 taken 14 f? (two
with egg-ball and one with spermatophor), 3 y?(V), 2 yd (V) at Skutulsfjord and 23/s? in Gunolfsvig—
(N. East Iceland) 50 f?, 5 y2(V), to yd (V) and 1 yo (IV).

South-West of Iceland. To the south-west of Iceland 10 mature females, 5 y?(V), 3 mature
‘males and 5 young males (V) were found 13/, 1896, St. 80, P. roo—o fm. 61°02 Lat. N. 29°32 Long. W.

South of Iceland. To the south of Iceland a single male was taken by the Ingolf Exp. (?7/s
1896, Cyl. 32, 63°45 Lat. N. 22°37 Long. W. 2 9; 20‘); §/s 1896 a mature female of Ps. gracilis, and from
™3/,19/. 1896 at three stations females of Ps. elongatus were taken; of the latter young animals (V)
were taken at 3 stations (°/,—3*/.), y? (IV) at a single station (3"/, 1896) and young animals (III) 3°/; 1895
and 31/; 1896. The East Greenland Exp. 1900 has taken a few mature and young females south of
Iceland 25/,.

In the Icelandish fjords adult males have been taken several times by different collectors. On
the north coast it was only taken once [Ingolf '/s 1896 Selvik in Skagafjord 65°58 L. N. 19°50 L. W.
Pl. 4 y?(V), ris, 5ydh(V), 7 yh (IV), 10 y (III) and 2 y (IJ)|. On the east to west coast males were
taken 3 times (13/,—*6/, 1902), and females as well as juniores (stage II—V) were jn several samples
found common from 13/,—?6/,.

South-East of Iceland. In the Iceland-Feroe channel south east of Iceland Ps. gracilis (f9)
were taken in four samples between ™/,—"/, 1895 and 2°/; 1896, and Ps. elongatus ({2—¢) in four samples
(t1/,—1°/, 1895 and 2°/; 1896); young animals (IV—V) were taken three times (!*/;—13/; 1895 and 7°/; 1896).
Several males were found in a single sample from "/, St. 1, V.t 50—o0 fm. 62°30 Lat. N. 8°2r L. W,,
including 140 f, 23 y?(V), 8 y? (IV), 30fd, 20 yh (V) and 5 yd (IV). From St. 3, ™/;, V.t r0o0o—o fim.
11 f? and 1 fg were found and from St. 4, '3/, 1895, V.t 100—o fm. 64°07 L. N. 11°12 L. W. 37 f2, 3 y? (V),
1 y? (IV), 2g and 4 yo (V). From St. 57, 7°/; 1896, V.t roo—o fm. 63°37 Lat. North 13°02 Long. West,
r £2, r yP (V) and 2 fo were secured.

North-East of Iceland. To the east and north-east of Iceland as far north as Jan Mayen
specimens (f9) of Ps. gracilis were found in four samples, taken between '°/, and 25/, 1896, and Ps.
elongatus in six samples (%°/,—*5/;); young animals (IV—V) of the former type from 3 Stat. (%/,—%5/,)
and of the latter from g Stat. (!°/,—5/, 1895); the following stage (III) was taken at 6 Stat. (*/,—5/s).

The East Greenland Expedition 1900 has from 2!/, to 2/, in the Norwegian Sea between 63°16
Lat. North 1°14 Long. East and 72°30 Lat. N. 6°41 Long. W. collected a few samples containing this
species (type: gracilis or elongatus) all taken at the surface (F. or G.).

The mature female was only taken once (?!/6 12 p. m. F. 33, 64°17 Lat. North 0°51 Long West);
young animals (V) were taken in 7 samples, including that from the most northern station, young
animals (III—IV) were found in four samples. As the species was only taken in few specimens, in
altogether 7 samples, though one sample was taken each hour day and night from 2*/s to 1°/, as far
north as 74°28 Lat. North (15°36 Long. West), there is good reason to regard it as extremely scarce
at the surface at the season and in the region mentioned.

The expedition has taken the Ps. elongatus a few times in Nansen’s closing net.

COPEPODA 63

Viz: *#/6 1 p.m. 64°17 L. N. 0°51 L. E. 75—50 fm. 1 f9; 3 y2(V): 1 yP (IV); rid; 3 yh (V); 3 yo (IV);
ry (III); 1 y (ID).
4o—10 im. 1 £2; 6y2(V); 5y? (IV); 9yh(V); 9 yh (IV); 7 y (HI).
25/6 Jan Mayen 50—60 fm. 5 f9.
1/5 100—50 fm. 1 f?.

Johannes Petersen has 1/, 1901 at 73° Lat. North and 8° Long. East taken 60 f9, 99 y?
(V), 9 y2? IV), 72 yh (V) and 5 y& (IV) of Ps. gracilis.

East and South-East of the Feroes. To the east and south-east of the Feeroes mature females
of Ps. gracilis were only taken 7/, 1895 and °/; 1896, while those of Ps. elongatus were taken in 3
samples (5/; and 19/g 1895) and in 9 samples by Ingolf 1896 (4/,—®/; and */s). Mature males were taken
®/. 1895 Cyl. 2 [59°17 Lat. N. 3°26 Long. E. 3 f9; 1 fs], 4/; 1896 Cyl. 4 [58°29 Lat. N. 5°o Long. E. 16 f9,
3y2(V), 2y2(IV), 2 fd, 6 yd (V), 2yd (IV), xy (IID)], 5/; 1896 Cyl. 6 [59°18 Lat. N. 3°08 Long. E. 5 f9,

ry? (IV), 1 fs, 1 y (IID), 5/; 1896 Cyl. 8 [61°00 Lat. N. o°10 L. E. 9° C. 33 £2, of which one with sperma-
_tophor, 1 y? (V), 1 y? (IV); 8 id, 6 yh (V)], °/s 1896 Apstein 81 [63°45 Lat. N. 7°10 Long. W. 1 fd; 1 yo
(IV); ry (IID], %3/s 1896 Klakvig Ankerplads the Feroes 1d‘, 17/3 96 Cyl. 44 [60°50 Lat. N. 0°25 L. W.
6 £9, 8 y2(V), toy2(IV); rid, 14 yh (V), Syd (IV); 4 y (II); ry (ID and 17/3 1896 Cyl. 47 [59°40 Lat.
N. 2°12 Long. E. 11 f9, 1 y? (IV); 1 ff; 1 y (II])]. Young animals (V) were taken 5/, 1895 and in 9 samples
1896 (4/;—®/;; %/s—t7/s), young animals (IV) only in 5 samples (4/;—®,; and 17/3 1896), jun. (III) in 3
samples (4/;, °/;, 17/3 1896) and juniores (II) ¢/; and '2/s 1896.

E. Bay has ™/s 1891 58°03 Lat. N. 2°08 L. W. taken 50f?, 3: y?(V), 16 yQ(IV), 3id, 16 yd
(V), 19 yo (IV), 9 y (IIT) and 2 y (II). Mortensen has 3/6 1899 at Kalbarsfjord, the Feroes, 40—10 fm.
taken 3 females with spermatophores and Rink has "/, 1848 at the Orkney Islands taken 6 f9, 4 y9,
3 id and 3 yd.

If any conclusions with regard to the occurrence of the three mentioned types can be drawn
from the above, it must be that Ps. major is only found in the open sea in Davis Strait, probably
not at the surface, that Ps. elongatus is often found at the very surface, most common in samples
taken comparatively near the coast, though in no wise scarce in those from the open sea, and that
Ps. gracilis seems to be a more northern and more oceanic form.

Propagation. As it is generally recognised that the mature males of the pelagic copepodes,
especially in species in which the manducatory limbs are rudimentary, only live a comparatively
short time, we are right in concluding that the seasons in which we find mature males are those of
the propagation of the species; specimens with spermatophores attached to the genital somite and
with egg-balls indicate the same.

Mature males have been found south-east of the Feeroes ®/, 1895 and in 4 samples 4/;—®/, 1896,
in the Iceland-Fezroe Channel at 3 stations ™/,—‘3/; 1895 and 2°/, 1896, south-west of Iceland 13/, and
7/3 1896, in Denmark Strait at 2 stations 19/;—*°/; 1895, in various Icelandish fjords, in 5 samples 3/;—
30/, 1895—1902, at the Orkney Islands '*/; 1848; 3/6 1899 a female with spermatophor was taken at the
Feeroe Islands; 1'/5 1891 mature males were taken south-east of the Feeroes; north-east of Iceland (as
far north as 66° Lat. North) mature males were taken 25/, 1895 (+ females with spermatophores)

64 COPEPODA

and #*/5 1900. In Davis Strait mature males were taken "/, 1895 and at Egedesminde etc. in 6 samples
from 23/,—°/, 1890.

From the north of Iceland males were taken '/s 1896; from the Feroes and the Norwegian Sea,
south-east of these Islands, they were taken in 5 samples from 7/s—*7/s.

As only very few samples were taken from the explored regions at other seasons (from Norwe-
gian Seas none June—July 1895—96), we do not know if propagating took place at other seasons.

Mature females were taken in Denmark Strait '9/;—3°/; 1895, in Davis Strait *5/;—28/, 1895 and
23/,—®/, 1892, south-west of Iceland 13/5 1896, south of Iceland 13/,—19/; 1896, 7/s 1896 and 25/, 1900,
south-east of Iceland ™/;—14/,; 1895, 2°/; 1896, north-east of Iceland */,—25/, 1896, %/s—25/6 1900 and
™/, 1901, south-east of the Feroes 4/; and 19/s 1895, 4/,—°/; and "/s 1896. The copepodites (V—IV)
were practically found in samples from the same dates, the only interesting exception being their
occurrence at Disco Bay 9/,, 1892; the copepodites (III, II) were only found at very few stations, pro-
bably on account of their small size.

Distribution. The Pseudocalanus minutus Kr. has its main distribution over the northern
part of the Atlantic Ocean, on the west side as far south as the Gulf of St. Laurence, and on the east
as far south as 35° Lat. North; it has been mentioned from the Black Sea, the Gulf of Suez and the
Mediterranean. In the Arctic Ocean it is known from Baffins Bay to the New Siberian Islands, and
has once been recorded from the west coast of North America (Puget Sound).

Farran, mainly on material collected by the International Investigations, has given a fairly
exhaustive account of its distribution and the points of its biology. It is most often abundant in the
Baltic, except in the Gulf of Bothnia, in the Belts, Kattegat, Skagerak, along the coast of Norway,
in the English Channel, the Irish Sea and in coastal waters on the south and west coasts of Ireland.
“In the North Sea south of 55° it is always present but usually scarce, sometimes abundant”. In the
north-west of Scotland, there is an indication of periodicity in its occurrence as well as of curious
variation from year to year; it was common in August 1903, moderate in August 1904 and 1906, scarce
in August 1907, and absent or almost absent in August 1905. In the Feroe and the Feeroe-Iceland chan-
nel the recorded distribution is somewhat irregular; during several years it has been found fairly common
in May and August (in 1906 almost absent). “On the south and west coast of Iceland it is generally
distributed in the open sea ten miles or more from shore, but it is usually rare, and often absent from
the tow-nettings. In the coastal waters it may be found frequently, and often forms large shoals”. On
the north coast of Iceland it has been recorded by Paulsen.

In the Norwegian Sea and southern Arctic Ocean between Jan Mayen and Iceland on the west
and Norway on the east it is in any case sometimes common or abundant.

On the west coast of Greenland it has been recorded by Vanhéffen from Umanak Fjord
(1897) and rather abundantly from the surface down to 240 m. adults as well as copepodites by
Stephensen from Northern Strémfjord about 67°40 Lat. North (range of temperature 0° to 3°2° C).

From the east coast of Greenland it has been recorded by Cleve 74°15 Lat. N. 18°15 Long.
W. and by Koefoed, who has found specimens (1°42 to 17 mm. long) at 4 Stations between 78°09
and 77°35 Lat. North, and 14°or and 18°02 Long. West from the surface down to 65 met. (Temperat.
+1ro—+17°C), which he thinks ought to be referred to Ps. clongatus rather than to Ps. gracilis.

COPEPODA 65

As the Duc d’Orléans is the expedition which has made the most systematic plancton-in-
vestigations from different depths with measurements of salinity and temperature, and as Koefoed
and Damas are the only ones, who have separated the three types, I think a more detailed survey
of their material, should pay.

Ps. major, which was first recorded by G. O. Sars north of the New Siberean Islands, was
only taken a single time 78°05 Lat. N. 5°21 Long. W. *°/, 1905 between 800 and 1350 met. (salinity
34°95 °/oo; temp. 008° — + 0°37° Cels.).

Ps. elongatus was only taken near the coast of Spitzbergen (c. 80° Lat. North 14°33 Long. East)
at 4 stations near the surface (Temp. o'50—2'50° C.) and at the mentioned stations near East Greenland.

Ps. gracilis, which has previously been recorded by Sars at the coast of Finmarken and _ be-
tween Finmarken and Baren Island “a été capturé entre 600 métres et la surface; il est particuliére-
ment abondant au-dessus de 200 métres; d’aprés les estimations faites par Koefoed, il parait moins
- fréquent le long de la cdte grénlandaise qu’ au large, mais il est trés fréquent tant dans le Gulfstream
que dans le courant polaire”. The species is generally missing in hauls from o—2o0 meters, but it has
been found common here at a few station (c) independent of the time of the day and of the temperature
(lying between + 1-70 and + 1°50). It has been found common at a depth between 480 and 600 metres,
juniores between 800—1000 metres (p. 270), and abundant at temperatures from + 1°70 to + 3°C. The
salinity, at which it is found common, varies from 30°60°/ to 34°90 °/oo-

As set forth by Farran the conditions at which this species can flourish are very varied.
The salinity varies from 7°25 °/oo to 35°30°/oo, the temperature from + 1°70°C. to 12:47° C, it is found
from the surface near the coast, where it is often left in tidal pools, as deep as 600 metres in the
open ocean. About the details of its biology I refer to Farran, several interesting studies of Herd-
mann from the Irish Channel but especially to Kraeeft, who in the Baltic and the North Sea has
studied the growths and the occurrence at different depths of the various stages (juniores). He writes
(1910 p. 79) “es zeigt sich deutlich dasz das III Stadium von Schicht zu Schicht, von Boden nach der
Oberflache gerechnet in immer grészer werdenden Menge vorhanden ist”; he found that mature females
(April 1906 in the Baltic) were present in 591 °/, between 75 and 30 metres, but only in 3:1 °/, between
5 and o metres.

About the time of propagating I have in the literature only found that the Duc d’Orléans has
collected mature females and males (°/, 1905 80°13 Lat. N. 7°42 Long. East 400 —500 metres, 0'23—0'80° C.,
and 15/s 1905 71°22 Lat. N. 18°58 Long. East, 200—400 metres, 0°67—1°53° C.).

Remarks. It has previously been mentioned that no characters are found by which all spec-
imens could be referred to one of the three types of Pseudocalanus minutus; in the same sample inter-
mediary links are found not only between the extremities of the mature females but also between
the copepodites of stage IV—V, in which however the difference between the types is less marked.
The question how to explain marked differences in size and other characters found in the same sample
under the same biological conditions, if they all belong to the same species, is too vexed to be ans-
wered now. Specificness of the different types may perhaps be excluded by the examination of several
hundreds of specimens at least, from samples with marked variation between the specimens, after

Galton’s statistical methods.
The Ingolf-Expedition. II. 4. 9

66 COPEPODA

Some of the differences are certainly congenital, but others are probably due to the fact that
specimens, which later on are found under identical biological conditions, are born at different localities
and have got a different start in life, before being carried by currents or other agencies to their

present abode.

i. Microcalanus pygmeus G. O. Sars.

1900. Pseudocalanus pygmzus n. sp. (?) G. O. Sars, pp. 73—75 | 1907. Pseudocalanus pygmezeus G, O. Sars. Damas and Koefoed,
pl. XXL pp. 396 and 407.
Spinocalanus longicornis n. sp. (¢) G. O. Sars, pp. 77 | 1908? Microcalanus sp. Farran, p. 28.
—78, pl. XXII figs. 13—14. 1908. -—— pygmzeus G.O. Sars. vy. Bremen, p. 26 fig. 24.
1g0I. Pseudocalanus pygmzus G. O. Sars. Th. & A. Scott, — pusillus G.O Sars. v. Bremen, p. 27 fig. 25.
. P. 339- 1908? — oa — Wolfenden, pp. 41—42,
1902. = _ — Mrazek, pp. 508— pl. Il fig. 5.
509, taf. V figs 3—11. 1908? -- a — Hj. Brock.
1902? — _ G. O. Sars. Giesbrecht, p. 20, | Ig1o? _ — _— Kraeeft, pp. 98—99.
taf. 2. Igi1? — — _ Farran, pp. 98—g9.
1903. Microcalanus pygmzus G. O, Sars. G. O. Sars, p. 157. Igii? _ "ea —_ Wolfenden, p. 286.
? Microcalanus pusillus n. sp. G. O. Sars p. 156—157; sup- | I913. _ pygmezeus G. O. Sars. Stephensen, pp. 311
plement pl. II, pl. III fig. r. --312.

Description. £9. Most of the examined full-grown females agreed fairly well with Sars’ descrip-
tion of AZ pygmeus. The size of the specimens varied from 065 to og mm. In a single specimen (St. 8)
the antennulae scarcely reached the end of the first abdominal somite, and the terminal spine of the second
pair of legs of this, as well as of other specimens, had indication of the serration which according to
Sars forms the chief characteristic between J. pygmeus and pusillus; as the natatory limbs were
broken in most of my specimens, I was unfortunately unable to examine this character in most spec-
‘imens (cf. pag. 68). According to Sars the rostrum is represented by two “extremely small tentacular
filaments”; in my specimens, as in those examined by Mrazek and Kraeeft, these organs are
rather thick and more like teeth.
fg. Size: rrmm. The structure of the fifth pair of legs is very much like that figured by
Sars (Pl. I pes V #), but in my specimen the division of the left leg into 3 basal segments is more
indistinct.
¥ (St. V). The juniores (f\—Q Copep. V) are practically like the preceding stage, but for the
number of abdominal somites. The male differs from the females by less prominent first abdominal
somite and a fairly well developed fifth pair of legs (cf. Mrazek fig. 13).
Y (St. IV): Size: () 065—075; (JS) 065—o'—9 mm. In this stage with only 3 abdominal somites
are the same differences between males and females observed.
Occurrence. Considering its minuteness one can not wonder that this species has only been
taken from the following few stations by the Ingolf Exp.
Davis Strait: St. 29. 65°34 L. N. 54°31 L. W. 5/, 3.30 p.m. 1895. V. 50—ofm. Temp. at surface 3'5°
C19, rh, 4yP(V) Sy h(V).
West of Iceland: St. 95. 65°14 Ly. N. 30°29 L. W. 77/6 5°25 p.m. 1896. P. too—ofm. Temp. at surface 7:8°
C. 169, 5yP(V), 26 yh (V).
St. 8. 63°56 L. N. 24°40 L. W. 9/,5 p.m. 1895. V. 10o—ofm. Temp. at surface 86°
Cary:

TE rd al, OP

COPEPODA 67

South-east of Iceland: St. 133. 63°14 L. N. 11°24 L. W. 9/3 96 1:30 p.m. P. 10o—ofm. Temp. at surface
108° C. 2 9, 2 yd (V).
St. 58. 64°25 L.N. 12°09 L. W. 7°/; 96 3 p.m. P. roo—ofm. Temp. at surface
ra°C. 7%, 2yP(V), 2yP(IV), 2yd(V), 2yh (IV), 1 y (III).
North-east of Iceland: St. 105. 65°34 L.N. 7°20 L. W. "/, 630p. m.96. Closing net. 700 fm. 119, 2 yd*(V).
St. 104. 66°23 L.N. 7°25 L. W. "/, 5:30a.m. Closing net. 850 fm. x 2.
East of the Feeroes: 60°05 L.N. 1°18 L. E. 17/3 1145—3'45 p.m. 96. Cyl. 46. ry oh.
West of the Freroes: 60°28 L. N. 12°10 L. W. the East-Greenland Exp. has 75/, 1900 F. 397
: taken ry 3 (V).
The mentioned expedition has besides taken the species from the polar seas east of Greenland.

74°28 L,. N. 15°30 L. W. */, 1900 Closing net 110—40 fm. 2 y$ (V), 2 y? (IV), 2 yo (V), 2 yo (IV).
72°02 L. N. 21°20 L. W. **/, 1900 6 a. m. Closing net 35—10fm.1 9, 1 y? (V), 1 y? (IV), 2 yo (V),
| 2 yd (IV).

Distribution. The JZ pygmeus G. O. S. was originally captured by Nansen (78°N. 136° E.)
in considerable numbers north of the New Siberian Islands in October 1893; by Bruce it was taken
at Novaya Zemlya ™/5 1900 and by Schaudin at Spitsbergen 81°32 L. N. The most important con-
tribution to its distribution in the polar seas and to its biology has been published by Damas and
Koefoed in the “Duc d’Orléans”. It has been taken at almost all the stations in the polar seas be-
tween Spitsbergen and Greenland as far east as 10°42 Long. East and as far west as 18°22 Long. West,
as far north as 80°17 Lat. North and as far south as 75°35 Lat. North between 2°/, and '°/s 1905. The
authors write (p. 396) “A@icrocalanus pygmeus posséde une grande amplitude verticale: il s’observe en-
core en abondance entre 1800 et 1:200 métres (St. 17) et ne manque dans aucun des échantillons pro-
fondes. Il remont fréquemment a la surface. Nos péches prouvent que son niveau habituel est au
dessous de 100 métres”. As all the information about each species, which is found under the gatherings
for each station, has not been collected for each species, I have tried to do it for A@icrocalanus pyg-
meus. Near the surface it has only been found: at St. 13 (0—20 meires, T. 030° C., Salin. 33°30 °%/co, 8/,
445 p- m.), at St. 30 (O—5 metres, T. 1:20° C,, Sal. 31°32 %/oo ?2/, 8 p.m.) and at St. 43 (o—20 met. T. 098°
— + 164°C. Sal. 32°/oo '/3 3 p.m.). As the salinity at which this species has been found lies between
3110 %oo and 35°%/oo the said authors may be right (p. 406) in referring it to the intermediary group of
species, which in the Norwegian Sea exceptionally are observed “a la surface surtout pendant la nuit
et dans les endroits, ot la salinité est elevée”; but their final statement, indicating a difference in the
vertical distribution in the different seas, about J. pygmeus (p. 407) “a) Dans la Bassin polaire: con-
staté a de faibles profundeurs. b) Dans la Mer du Grénland: principalement vers 100 métres; existe
depuis la surface jusque 4 1850 métres. c) Dans la Mer de Norvége: sourtout abondant entre 200 et
600 métres”, is neither born out by their own material (tab. II) nor by the information available in
the literature. The species has not yet been recorded from the Norwegian Sea. The temperature, at
which this species has been found even in great numbers (cc) at different depths, varies from + 1°75
to -++ 215°C.; it has been found fairly common (++) at 381° C, but its optimums temperature seems
to be a little below and a little above Zero. Adult males have been found at 11 stations in the Green-

land Sea between *'5/, and '5/s, in vertical hauls from 60 to 20 and from 1000 to 800 metres and at
9*

68 COPEPODA

a temperature between -++0'49°C. and + 175°C. In the literature I was unable to find any further in-
formation about this species, but about JZ. pusilus G.O.Sars, which possibly is identical with it, a
good deal of information is found. According to Farran (1910 pp. 98—99) it has been recorded from
several of the Norwegian fjords at considerable depths, and from the sea between Jan Mayen and
Finmarken. According to Paulsen a species, which Sars has determined as JZ pusillus, but which
really is JZ. pygmeus (cf. later on), occurred plentifully in a depth between 230 and 350 metres on the
north coast of Iceland ('4/s 1904 66°20 L. N. 12°10 L. W.). In addition it has been recorded from the
Irish Sea, the west coast of Ireland, the whole Norwegian Sea, the Skager Rak, the Kattegat and
in the extreme S$. W. Baltic off Bornholm.

At Spitsbergen (80°02 L. N. 17°02 L. E.) it was found by the “Duc d’Orléans” in a depth of from
60—30 m. (Temp. o'40—0'27°C.) and by Hofsten and Bock (150—4o m. D)).

The Belgian Antarctic as well as the National Antarctic Expedition has in the Antarctic Seas
collected a good number of a minute species by nets let down through holes in the ice to a depth
of 200—500 met.; they have been mentioned by Giesbrecht and Wolfenden respectively as
M. pygmeus and pusillus. The latter has pointed out that Giesbrecht’s description refers to AZ pu-
sillus (viz. comparatively short antennulae). Giesbrecht’s localities lie between 71°18 and 69°48 Lat.
South and 92°22 and 81°19 Long. W. If this identification is right, the species should certainly be found
in the deep sea all over the world.

Remarks. I am fairly convinced, that the characters, which Sars has set forth to distinguish
Microcalanus pygmaeus and pusillus viz: shape of St. pes IV and length of the antennulae are not
sufficient. In this point of view I have been even more convinced by examing some specimens from
the North of Iceland, placed at my disposal by the kindness of Dr. Paulsen and determined by
Professor Sars as AZ pustl/us. Most of the specimens were young males with the antennulae reaching
about to the middle of the abdomen; the spinulation of the St. of the natatory legs was not very
coarse. In a single specimen (lengt 084 mm.) the St. pes III has 16 dentations in proximal half in
contrast to Sars figure of AZ. pusil/us with 10 teeth, and to an adult female from Ingolf St. 8 with
about 20. It seems evident to me that Paulsen’s specimens ought to be referred to JZ pygmeus, and
the fact that even such an authority as Sars has difficulty in distinguishing the two species from
each other, makes reservation necessary with regard to several identifications found in literature, and
bears out my doubts with regard to the validity of the two species.

The partial value of the two main characters have been mentioned. According to Sars the
size of the adult specimens of JM. pusillus scarcely exceeds 0°77 mm.; several of my specimens are
smaller. Mrazek, who has examined ¢ and 9, varying in size from 060 to 0'75 suggests the possibility
of referring them to two species, and Kraeeft points out minor differences between his specimens of
M. pusillus and Sars’ decription. It may be admitted that a careful re-examination of a good material
from the different localities is necessary before settling the qustion of the identification of the species.

12. Clausocalanus arcuiformis Dana.
(Pl. I figs. 9a—d).
1849. Clausocalanus arcuiformis n.sp. Dana. 1894. Clausocalanus arcuiformis Dana. Th. Scott, p. 73, pl. 8.

1892. —_ _ Dana.Giesbrecht, pp. 185—190, | 1895. — _ — Giesbrecht p. 248.
taf. 1, 2, Io and 36.

COPEPODA 69

1898. Clausocalanus arcuiformis Dana Giesbrecht & Schmeil, | 1905. Clausocalanus arcuiformis Dana G, O. Sars, p. 3.
p. 27. 1906. _ -— — Pearson, p. 9.

1899. — — — Brady, p. 32. 1908. _— - — ov. Bremen, p. 23, fig. 20.
1900. — — Wheeler, p. 171, fig. 9. 1908. - — — Farran, p. 28.
1gol. _ _ — Cleve, p. 5. 1909. _ — — Pesta, p. 22.
1903. — — — J. C. Thompson & A. | 1909. — — — A. Scott, p. 32.

Scott, p. 243. Iglo, _— = — Steuer, p. 22.
1903. — -- — Cleve, p. 359. IgIo. _ — — Farran, pp. 91—92.
1904. _ -- — Cleve, p. 188, IgII. _ — — Wolfenden, p. 203.
1905. — — — Wolfenden, p. 999. IgI2. — -- — Pesta, pp. 20—21.
1905. — _ — Ksterly, p. 142, fig. 13. IgI2. — _ — Sewell, p. 360.

Description. Between the specimens desieribed by Giesbrecht and my specimens scarcely any
differences were found. As far as the oral surroundings are concerned they scarcely show features of
greater interest. Just behind the rostrum a low epistoma bearing a few rather short and strong
bristles (fig. ga) is found. In the middle of the /adrwm proper a rather prominent, narrow and hairy
process is found, on each side of which a group of rather short setae is seen. Posteriorly the labrum
is on each side produced into a hairy wing-like rounded expansion. The oral surface of the labrum
(Pl. I fig. gc) possesses on each side 3—4 longitudinal rows of short setae, and between these 3 trans-
verse groups, of which the posterior is the most developed.

The /amina labialis has three subdivisions. Orally and anteriorly two interiorly convex series
of hairs are observed on each side. The arrangement of the hairs behind the lamina labialis did not
show features of greater interest (Pl. I, fig. 9d).

Occurrence. This species seems to be extremely rare within the area explored by the Ingolf
Expedition; I have only examined 11 full-grown females and a single young one, which were taken
24/, 1889 59° Lat. North and 17° Long. West.

Distribution. The species has previously been found on the west coast of Ireland’, In the
Mediterranean it has been recorded by several authors. In the northern as well as in the southern
parts of the Atlantic Seas it has been captured by the Monaco and the German Antarctic Expeditions.
On the west coast of South America it has been found as far south as 53° S. By Wolfenden it is
recorded from the Maladive Islands and from the Antarctic Seas as far south as Lat. 84°o1, and by
Brady from New Zealand (at the surface). In the Pacific Ocean it has been found between 20° Lat.
North and 26° Lat. South. Vertical range from the surface to 4ooo met. Cleve has found the species
in the Arabian Sea (Temperat. between 24°8° and 267°C. and salinity between 3620 and 35°77 °/oo),
the Indian Ocean (7—4° Lat. North T. 27°7°—29°35° C., Sal. 30°4—34°38 °/oo) and in the Malay Archipe-
lago (T. 25°3°—28-30° C. Sal. 32°22—3380°/..). According to Scott (1909 p. 32) it is moderately common
over the whole area investigated by the Siboga Expedition.

13. Spinocalanus abyssalis Giesbrecht.
(Plate I figs. 1oa—b; textfigs. 15a—e).

1888. Spinocalanus abyssalis n. sp. Giesbrecht. 1900; Spinocalanus longicornis n. sp. (Q) G. O. Sars, pp. 75—78,
1892. — — Giesbr. Giesbrecht, 1892 pp. 209 pl. XXII.
—213, taf. 13 and 36. -

1 According to Farran (IgI0 p.g2) “it is occasionally carried by currents into the mouths of the English Channel
and the British Channel, but has not yet been recorded from the west or north coast of Scotland”, (Salinity 35°4 °/oc).

70 COPEPODA

1902? Spinocalanus Schaudinni n. sp. Mrazek, pp. 509—512, | 1903. Spinocalanus abyssalis Giesbr: G.O. Sars, pp. 157—158;

taf. IV, taf. V fig. 1. supplement pl. III fig. 2.
1903. — longicornis G, O. Sars. G. O. Sars, pp. 22— | 1908. — -- — yv.Bremen, pp. 28—29, fig. 27.
23, pl. XII. 1908. — — — Farran, p. 27.

Description. f?. Size: varied from 1°73 to 186 mm. Sars’ specimens measured r1—16 and
Giesbrecht’s r1—r-25 mm.

The specimens which I have examined are certainly to be referred to Gbt’s species in spite
of minor differences, in which I most often agree with Sars’ description. The head and the first
thoracic segment are completely fused except in a single specimen, in which there was indication of
a subdivision. The fifth thoracic somite is, as seen in text-fig. 15a, only indistinctly marked out in front.
The ventral protuberance of the genital somite is less prominent than figured by Giesbrecht, and

more prominent than drawn by Sars, and the shape is somewhat different.

a d
\
b c e
Text-fig. 15. Spinocalanus abyssalis Giesbr.
a. £9. Abdomen X 170. d. yo (stage V). Abdomen X 170.

b. fo. Lateral thoracic corner X 170, e. yo (stage V). Pes V X c. 225.
c. fo. Pes V in anterior view X 225.

The oral appendages are scarcely different from Giesbrecht’s description. In the structure
of the natatory legs a few differences are observed. The number of bristles which are present on the
anterior surface of the second basipodite are fewer in number than figured by Giesbrecht. The exte-
rior seta of the first outer segment of the first pair of legs is distinctly more slender than that of the
following segments. The number and the arrangement of the spines or setae which adorn the surface
of the exopodites and endopodites in the last three pair of legs show variations from specimen to
specimen, and are not quite like Giesbrecht’s description; in most specimens f. inst. short spines
are observed, as figured by Sars (Pl. XII), not only on the posterior, but also on the anterior surface
of the two last segments of the endopodites. In the second pair of legs the usual glandular pores were
observed at the base of the exterior seta in the two last segments; none was observed in the basal
segment.

The /abrum proper is less prominent than figured by Sars (Pl. III 2c). In front of the hinder

margin in the middle a transverse row of long bristles is observed, but here none along the margin

COPEPODA 71

proper; laterally a series of short setae is observed (Pl. I fig. 10a), and in front of these, partly on the
oral surface, a group of short spines or granules is observed. Orally we find on each side an inner and
an outer series of delicate bristles, arranged in a short posterior and a long anterior division. As far
as the structure of the labium etc. is concerned I refer to the fig. rob.

£3. Size of male 163 mm.

The thoracic somite IV and V are as seen in the text-fig. 15b well separated. The anxtennulae
have the articular-membranes between the segments 8~9g and 10, 10 and 11, 11 and 12 rather in-
distinct; the antennulae become rather suddenly narrower beyond segment 14, which is wider than
15, The first to ninth segments possess two bristles in addition to one or two “Aesthetasken”; in the
following segments, except in the 12th, no distinct proximal seta (Spr.) is observed, but small incisions,
corresponding to their insertions; “Aesthetasken” are observed in several of the segments. The oral
appendages are as shown and partly figured by Sars rather rudimentary. The maxzlludae show the
- following features. The Le possesses 7 short bristles; the Li I has only a few rudimentary setae, and
the rather prominent Li II—III have 3 short delicate bristles each. The Basp. has 5 and the Ri I—III
4+4-+ 6 bristles, of which those of Ri III are fairly long and slender. The Re bears 11 partly power-
ful hairs. The mandibles are figured by Sars; the antennae, the maxillae and the maxillipeds are
less powerful, but in the main features alike those of the female. The /adrwm and labial appendages
show exteriorly a structure scarcely different from that of the female.

The Se of Re I pes I is even less developed than in the female. The structure of the fifth
pair of legs (cf. text-fig. 15 c) is in some points different from Sars’ description; between the Re I and

II on the right side an indistinct limitation is seen.

Y (St. V). Size: 145 mm.; anterior division 100 and the abdomen o45 mm.

The shape of the body is scarcely different from that of the female; there is indication of
articulation between the head and first thoracic somite; the two last thoracic somites are, as seen in
text-fig. 15 d, well developed. The oral and natatory appendages are scarcely different from those of
the females. The structure of pes V is shown in text-fig. 14.

Occurrence. The Ingolf Expedition has taken 2 mature females, a single mature male and
two young ones (St. V) 7/6 1895 2 p. m. V'. 200—o0 fathoms St. 25 63°30 Lat. N. 54°25 Long. W.

Distribution. This species has been taken at 2 different stations in the polar seas in about the
8oth degree of latitude and the 134th degree of longitude east as well as at 81°32 L.N. by Romer
and Schaudinn, on the coast of Norway (Osterfjord Norway in the depth from 400—600 metres),
and in moderate numbers on the west coast of Ireland “at all depths from 200 to 1000 fathoms”. Ac-
cording to Giesbrecht it is found “g99°—132° W. 3° S.—14° N. In 1000—4000 Meter Tiefe”.

Remarks. The female described by Mrazek as Spinocalanus Schaudinni is certainly identical
with the mentioned Species. His male, however, seems in rather important features to differ; in his spec-
imen the segments VIII to XIV of the antennulae are completely fused (Taf. V fig. 1), and the pes V
differs distinctly, especially by the Ri, the terminal seta of which just reaches beyond the end of Re I.

72 COPEPODA

14. Spinocalanus magnus Wolf.

1904. Spinocalanus magnus n.sp. Wolfenden, p. 118. 1908. Spinocalanus magnus Wolf. Farran, p. 27.

1905. = — Wolf. Farran, pp. 30—31, pl. 1V | 1908. _— — — v. Bremen, p. 29, fig. 29.

figs.1—12. | 1911? — on — Wolfenden, pp. 216—217,
1906. — _ — Pearson, pp. Io—II. | text-f. 8, pl. XXV figs. 3—5.
1907. - a — Damas & Koefoed, p. 409.

Description. £9. Size of female from Thor St. 82 28mm.; anterior division measured 2:2; uro-
some o6 mm. Wolfenden’s specimens measured 2°75 and Farran’s 2:9 mm.

As far as could be made ott by the examination of the two very mutilated specimens, they
do not seem to differ in any feature of interest from Farran’s description.

In the second pair of legs no glandular pores were observed in the first outer segment, but a
distinct one in the second segment, and three near the base of Se in the third outer segment.

In front of the labrum proper, which is very prominent, a smoothly rounded elevation was
found; the structure of the labrum etc. was not examined in detail.

Occurrence. Of this species I have only examined two mutilated females, gathered by the
Thor "4/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire.

Distribution. This species is according to Farran of frequent occurrence on the west coast
of Ireland “from the surface to rooo fathoms, though never very plentiful”. According to Koefoed
& Damas it is found “dans la mer du Grdnland: de 800 A afi moins 1-800 metres”. According to the
tables prepared by Koefoed, it has been found at four stations, but according to the records from
each single station it has only been found at St. 22 79° L. N. 1°52 L. E. 800—1350 metres and at St. 48
71° L. N. 18°58 L. W. 800—1000 metres. The species is by Wolfenden recorded from the Antarctic,
but he is probably not right in referring the Antarctic animals to the northern species, as his figure

shows the genital somite less distinctly produced.

Aetideidae G. O. Sars.

Little by little a good many genera of the Aetidetdae have been established; these genera are not
at all of equal value, and in their definition not the same principles have been followed. My material
has not been sufficiently exhaustive for a final solution of the question, but nevertheless a few remarks
upon the value and the position of the genera, which I have examined, may be useful.

As a whole I think that undue stress has been placed on the presence or absence of the
lamelli-formed setae or spines along the inner margin of second basipodite in the fourth pair of legs.
Chiridius and Actidiopsis are the only genera in which marginal setae of usual structure without
spines are found; in Aeézdius (Pl. II fig. 1c) terminally and posteriorly a few teeth were found in
addition to the usual slender setae. In most species of Gatdius, Gaetanus and Euchirella the setae are
transformed into more or less well developed spines. In Underchete minor and nearly related species
the margin is either completely smooth or possessses a few terminal teeth (cf. text-figure) and in Chzra-

dina, the margin is either completely smooth as in Ch. Streetst, or possesses well developed spines

COPEPODA 73

(Ch. abyssalis and pustulifera). Corresponding to the difference between the mature females and males
a difference is sometimes found between the two sexes in the penultimate stage; in Gazdius tenuispr-
nus and Euchirella rostrata f. inst. the young female has along the inner margin of the second basi-
podite in the fourth pair of legs a few lamellous setae, while the young male has a few of usual
structure; in most species of Zuchirella and Chirudina the margin is smooth in both sexes in the
penultimate stage.

The Aetidius is a well characterized genus which, as far as can be concluded from the wanting
glandular pore in ReI pes II and the well developed marginal setae in the fourth pair of legs, is a
rather primitive form. The Chiridius, to which genus I refer not only Ch. obtusifrons without distinct
rostrum, but also Ch. armatus in similarity to Sars and in contrast to Vanhdffen and Wolfenden,
is among other features characterized by the wanting plate-shaped process of the second basipodite of
the maxillipeds, the well developed exopodite of the first pair of legs with 3 setae, and the slender
' marginal setae of the fourth pair of legs; as Giesbrecht had originally established the genus for a
species without rostrum, Wolfenden and Vanhdffen have accepted the name Pseudoactidius for
Ch. armatus; Sars has judged this single character as being of minor importance, and he is certainly
right, especially when it is taken into consideration that a rudimentary slightly bifurcate rostrum is really
found. On account of the great number of glandular pores in the three last pair of legs (Pl. II figs.
3—5a) I once thought that Wolfenden was right; but as Cz. modestus u. sp., which in other respects
was like Ch. armatus, has 3 glandular pores (including one in Re I), I definitively accepted Sars’
definition. Sars has established a new genus #¢idiofsis synonymous with Wolfendens Faeroella,
especially characterized by well developed fifth thoracic tergite; as a fairly well marked fifth somite
is found in most specimens of Ch. armatus, I do not think this genus is a good one. A. Scott’s new
genus Gaidiopsis (1909 p. 52), characterized by a very robust rostrum, is probably nearly related to
Chiridius.

The genera Bradyetes Farr. and Undinopsis G. O. Sars (synonymous with Bradyidius Giesbr.)
are nearly related; Psewdocuchete Sars is according to Farran related to these genera as well as to
Bryaxis Boeck, the position of which seems to be a little doubtful on account of the poorly developed
outer ramus of the antennae. The position of Sars’ genus Chiridiella is very doubtful. I have not
had the opportunity of examining any specimens of the last mentioned five genera.

According to Giesbrecht (1892 p. 249) the genus Gazdius has “rostrum kurz einspitzig”
and “Aussenast des ersten Fusses zwei ... und Innenast des 1. und 2. Fusses eingliedrig” and the only
difference from Gae¢anus is found in the frontal spine and the two-segmented endopodite of the second
pair of legs of the latter genus. The character found in the segmentation of the endopodite
of the second pair of legs is not of much value, as this articulation is well developed in
most species of Gaefanus as well as in Gardius brevispinus, slightly developed in Gaetanus miles and
Gardius tenuispinus, and completely wanting in Gaetanus minor. ‘The presence or absence of the frontal
spine seems to me to furnish a good specific, but scarcely a generic, character; Sars seems to share
this opinion, as he has established a Gaefanus inermis without any spine. Wolfenden has established
a new genus Mesogaidius (1911 p. 223) for his MZ. intermedius, perhaps identical with G. brevispinus, and

his JZ, maximus, because they combine the wanting frontal spine with “das Vorhandensein eines Zipfel
The Ingolf-Expedition. III. 4. Io

74 COPEPODA

am Aussenaste der hinteren Antennen und einer eigentiimlichen Chitinlamelle am Rande der hinteren
Maxillipeden”. The former character is found in G. ¢enuispinus as well (PI. III fig. 2b), and the latter
is scarcely sufficient; the exopodite of the first pair of legs of JZ. maximus has 3 distinct segments,
each with a well developed outer seta, a character not found in any Gazdius or Gaetanus known to
me. If we regard the following species of Gazdius and Gaetanus as forming one group, the natural
division will probably be the following: 1) the Gardius tenuisfinus which has no frontal spine and
no lamina in the second basipodite of the maxillipeds; the second segment of the exopodite of the
antennae possesses a distinct process for the second seta, the first segment of the exopodite in the
second pair of legs has no glandular pore, and the inner margin of the second basipodite in the fourth
pair of legs in the young females has a few stiff setae, while in the young males it has a few
of usual structure, 2) the Gazdius brevispinus which has a well developed lamina in the maxillipeds
of the female, and the male of which has not a minute outer seta in the second segment of the
exopodite in the second pair of legs, 3) the Gaetanus Krupfi and Jlatifrons, which differ from the two
preceding species by the frontal spine, and the presence of ten instead of eleven setae in the exopodite
of the maxillulae, but in other respects, except the lamina of the maxillipeds, agree with G. tenuispinus
4) Gaetanus minor which, except for the wanting glandular pore in the first outer segment in the second
foot, completely agrees with the preceeding group; and 5) Gaetanus pileatus and miles, which in ad-
dition to the wanting glandular pore of the second foot do not possess any process in the second
outer segment of the antennae, and have the inner margin of the second basipodite in the fourth foot
smooth in both sexes in the penultimate stage. For settling definitively the question of the relative
position of the species, the structure of the fifth foot in the male of G. miles must be known. At
present I am inclined to regard Gaidius tenuispinus and Gaetanus Kruppi as being more nearly related
to each other than the latter species is to Gaetanus miles. In addition to the mentioned characters all
the enumerated species have the lamina labialis rather simple, without the division in three portions
as in Euchirella, in contrast to Chiridius and Aetidius. The position of Chirudina, to which not only
Ch. Streetst but also pustulifera, abyssalis, notacantha, parvispina and spectabilis are referred, is a little
doubtful. These species are in several respects rather different, but show their affinity by the structure
of the oral surface of the labrum, and the structure of the fifth pair of legs in the male; the second
outer segment of the antennae have distinct setigerous processes, the outer surface of the maxillae
(Pl. V figs. 5c) is not very produced, the maxillipeds have a rather characteristic structure, the exo-
podite of the first foot is more or less distinctly three-divided, with three outer setae, and the glandular
pore of the first outer segment is wanting in the second foot; the inner margin of the second basi-
podite in the fourth pair of legs is either more or less smooth, or has a distinct corona of spines in
the mature female, but is completely smooth in both legs in the penultimate stages. Some of these
characters suggest affinity to Chiridius, others to Gaidius; if Wolfenden’s Mesogaidius maximus
with a lamina in the maxillipeds, and the outer edged spines in the second pair of legs, really belongs
to this genus, a connecting link with Gazdius is found. The three last species ought perhaps, on ac-
count of the structure of the fifth pair of legs, to form an independent genus, and others, f. inst. Ch. pus-
tulifera, ought perhaps, as suggested by Sars, to be referred to Undenchete, the most nearly related genus.
As, however, the three or five species which I have referred to this genus form a well defined group,

COPEPODA 75

I have preferred to exclude other species of somewhat doubtful position, as well as to let Wolf-
enden’s genus Mesundeucheta go out. Though the different species of Luchirellu differ from
each other in several important features, I think the genus is a quite natural one, as it is not only
characterized by the structure of the antennae and maxillulae, but also by the presence of a glandular
pore at the base of Se I Re II pes II—IV (cf. Chiridius), which is wanting in the penultimate stage.
In Zuch. rostrata, messinensis, maxima and betumida a glandular pore is wanting in the first outer
segment in the second pair of legs, but in Z curticauda and intermedia it is wanting in the third
and fourth pairs of legs as well. In addition to the generally accepted specific characters, good ones
are found in the structure of the oral surface of the labrum, in the number of bristles of the exopodite
of the maxillulae in the males, and in the marginal hairs of the second basipodite of the fourth

pair of legs.

15. Aetidius armatus Boeck.
(Pl. II fig. ra—d; text-fig. 16).

1872, Pseudocalanus armatus n.sp. Boeck, p. 38. 1904. Aetidius tenuirostris n. sp. Wolfenden, pp. 116—117.
1883? Aetidius armatus n.sp. Brady, p. 75. 1905. — armatus Boeck. Farran, p. 31.
1892, nec. = — — . Brady. Giesbrecht, p. 213, taf. 2, 14 | 1905. — -- -- Esterly, p. 145, figs. 14 a—b.
and 36. 1905. » — — — Th. Scott, p. 222.
1893. pars. — — — Th, Scott, p. 70. 1906. = = — Pearson, p. II.
1898. pars. — _— — Giesbrecht & Schmeil, p. 31. | 1908. - -- — _v. Bremen, p. 30 fig. 30.
1gol. o _ Boeck. Th. Scott, p. 238. 1908. — — — Farran, p. 28.
1902. ~— =s — Th. Scott, p. 451. 1909? — =p — ,. Pesta, p. 23.
1902. cae re — G. 0. Sars, pp. 25—26, pls | 1909. — = — A.Scott, pp. 37 —38, pl. IV, figs
XITI—XIV. I4—25.
1903. > -_ — Norman, p. 136. IgIo. = == — Steuer, pp. 23—24.
1903. —- = — Jensen, Johansen, Levinsen, | 1910. — = — Wolfenden, p. 209, text-fig. 4.
p- 304. IgII. — _ — Farran, pp. 81—82.
1903? — es Brady. J.C. Thompson, p. 16.

Description. 9. Size of specimen from Ingolf St. 47, 1°93 mm.: anterior division (head + som.
thor. I 0920; somite II—V 0'575) 1495; urosome 0437 mm.

The head is as figured by Sars etc. vaulted in a characteristic way without frontal keel, and
the rostrum has two pointed branches without basal tubercle. The genital somite, which is both wider
and deeper than long, has a receptaculum seminis (text-fig. 16) which is distinctly dif-
ferent from that of A. Giesbrechtit Cleve 1904 (synonymous with A. mediterraneus
Steuer 1910), as seen by comparing figs 1a—b with Giesbrechts fig. 9 Taf. 36; the
vulva (fig. 1b) is also somewhat different from Giesbrecht’s fig. 8.

The measurements of the antennulae are distinctly different from those given
by Giesbrecht, as the segment 23 is shorter than 22, and as segment 24% 25 is
respectively 14 and 1°5 as long as segment 8% 9 and 2 (not 2 and 2'5). The antennae
differ from Sars’ as well as from Giesbrecht’s figures by the small process on which

Text-fig. 16.
the proximal seta of Re II is placed. The other mouth appandages show some dif- eae wetaeagg
oeck,
ferences from Sars’ figures, but not in any feature worth to be mentioned from Gies- Abdomen in left
brecht’s description. view X 57-

The pes I differs from Giesbrecht’s description (fig. 10) by the second basipodite, which has

no setae exteriorly and distally, and by the third one, which has no spinous area laterally and anteriorly.

10*

76 COPEPODA

The pes II has the articular membrane between Re I and II distinct anteriorly, but missing posteriorly;
the basp. II pes IV has, in addition to marginal row of setae, posteriorly and just proximally to the Si a
transverse row of 4 short spines (Pl. II fig. 1c), which corresponds to the two spines mentioned by
Giesbrecht but not by Sars and Scott. Glandular pores were found at the base of Se Re II and
Se 3 Re III in the three posterior pair of legs, and in addition to these a pore was found at the base
of Se Re I in pes III—IV.

The labrum is in lateral view like Sars’ figure, with a short anterior elevation, which by a
low incision is separated from the labrum proper; this is, anteriorly, evenly convex and, posteriorly
towards the free margin, slightly concave. In front of the marginal row of setae along the free poste-
rior margin no setae were found. The oral surface of the labrum is most like that of Gazdiws; the
longitudinal group 1 consists of a single series of fairly long hairs; the groups 2—5 are only in-
distinctly separated, and only the groups 4—5 are 2—3 setae deep. The lamina labialis and the setae

in front of it have a structure as shown in figure 1d.

Y? (V). Size of specimen from St. 45 1°58 mm., anterior division 1:23 mm.; urosome 0°35 mm.

This stage differs distinctly from that of the adult female by the structure of the abdomen.
The head is well separated from the first thoracic tergite, and the fifth from the fourth; the appendages
do not show any difference of importance, except the even less developed articulation between Ri I—II
pes II, and the wanting spines in besipodite II pes IV, which has however the usual marginal setae.

Occurrence. The Ingolf Expedition has gathered this species at the following stations viz:

t/, 1895 St. 27 64°54 L. N. 55°10 L. W. V*. 200--ofm. Temp. at surface 379°C. 1 f9.

26/6 1895 St. 25 63°30 L. N. 54°25 L. W. V*. 200—0 fm. Ps ge Oats ie
30/, 1895 St. 38 59°12 L. N. 51°06 L. W. V*. 100—o fm. p> ae, ee: YS
18/6 1895 St. 19 60°29 L. N. 34°14 L. W. V*. 300-0 fm. gt) C648
20/, 1895 St. 11 64°34 L. N. 31°12 L. W. V*. 200—0 fm. Sa°C. ate
12/, 1896 St. 47 61°32 L. N. 13°40 L. W. V*. 100—o fm. IO) Oates
5/, 1896 St. 52 63°57 L. N. 13°32 L. W. V*. 200-0 fm. ame gh Oona 6 4
20/; 1896 St. 57 63°37 L. N. 13°03 L. W. V*. r1oo—o fm. $:2° C71 29:
20/. 1896 St.59 65° LN. 11°61. W. Apst. 12 se at aaah as 1°)
™/; 1896 St. 45 61°32 L. N. 9°43 L. W. V*%. 100—0 fm. gi°C, 249. 2 yee

In addition to these Captain Wandel has 1891 at 67°07 L. N. 11°41 L. W. taken 1 £9, and the
Danish East Greenland Expedit. 1900 10 p. m. F. 403 has gathered a single female 60°29 L. N.
12°10 L. W.

Distribution. This species is according to Farran “a characteristic inhabitant of the lower
layers of the North-East Atlantic off the coast of Ireland and Scotland”: It has been found in the cold
as well as in the warm area of the Faeroe channel, the northern part of the North Sea, and several
of the Norwegian fjords. It has been taken off the Finmark coast N. W. of Nordkyn and north of
Iceland. The records of the Ingolf. Exp. show that it is also found in deep waters, probably as a
member of the Atlantic fauna, in the Iceland-Feroe channel, Denmark and Davis Straits. This

species seems to have a very wide distribution; according to Scott and Wolfenden the spec-

COPEPODA 77

imens which they have: referred to A. armatus are not to be distinguished from specimens from the
northern seas. The gulf of Guinea, the South Atlantic, the Indian and Malayan Seas ought accor-
dingly to be regarded as lying within the range of this species. Even if Sars is right, that some
of Brady’s specimens are identical with Boeck’s species, we are not right in concluding that the
species has the distribution stated by Brady (cf. A. Scott’s remark p. 37).

16. Chiridius armatus Boeck.
(Pl. II figs. 3a—e; text-figs. 17 a—d).

1872. Euchzte armata n. sp. Boeck, p. 39. 1905. Chiridius armatus. Boeck, Farran, p. 34.
1897. nec. Pseudocalanus -armatus Boeck. Vanhéffen, p. 279, | 1905. — —_ — G. O. Sars, p. 2.
: fig. 16. 1905. —- _ — Th. Scott, p. 222.
1goo. nec. Chiridius armatus Boeck. G. O. Sars, pp. 29—30. 1906. Pseudoaetidius armatus Boeck, Pearson, p. II.
1903. ~_ — — G. O. Sars, pp. 27—29, | 1907. Chiridius armatus Boeck. Koefoed & Damas, p. 408.
pls. XV—XVI. 1908, a — Farran, p. 30.
1903. — =_ -- Jensen, Johansen & Le- | 1908. Pseudoaetidius armatus Boeck. v. Bremen, p. 33,
vinsen, p. 304. fig. 34.
1904. Pseudoaetidius armatus Boeck. Wolfenden, pp.115 | IgII. Chiridius armatus Boeck. Farran, pp. 90—9I.
"and 131, pl. IV figs. 29—31. Ig13. nec — _ — Stephensen, p. 316.

Description. f. Size of specimens from Thor St. 172 measured 443 mm., anterior division
33 mm., urosome 110 mm. The smallest specimen (Thor St. 72) measured 3°6 mm.

The body differred in the following features from Sars’ description; laterally and beneath, the
limitation between the head and first thoracic tergite is indicated; the fifth thoracic tergite, which is
produced into well developed triangular points, is j b é
short, but well distinguished (text-fig. 17¢). The
genital somite is only slightly produced beneath, and
the receptaculum has, as seen in fig. 17d, a charac-
teristic structure. The furcal rami, which are a little
longer than the anal somite, are scarcely 1:3 as long
as wide.

The antennulae, which have the segment 25
well marked out with rather indistinct articular
membrane, have the segment 2 a little longer than
8~9, which is as long as the segment 20; the seg-
ment 21 is a little longer than 18, and the segment

23 is distinctly rz as long as 24. The arrangement
of the appendages is scarcely different from that of Ch.

obtusifrons ; the posterior seta of the segment 23 just eee iy Fie, CES, Orme DARE,
a. Head in dorsal view X 16. b. Head in lateral view X 60.

reaches the tip of the segment 25. The exopodite c. First abdominal somite in dorsal view X 50.
d, Lateral corner etc. X 60. e. Parasite attached to the

of the antennae is scarcely 14 as long as the endo- rigilt thesia X74,

podite. The Le 1 of the maxtllulae has as usual
g setae and the Li 2 possess 5 spinelike setae, the Li 3, which terminally on the anterior surface has a

curved row of short spines, has 4 setae, and the basipodite III has a similar row of short spines and

78 COPEPODA

5 setae. The Ri has 13 setae as the Ri I has 3 Sa + 1 Sp, and the Re has only 10 setae. The
posterior seta of the first lobe of the maxilla is at least 3 times as long as the lobe itself. In the
maxillipeds the third basipodite is about 1-3 as long as the second, and three times as long as the endo-
podite. The fourth lobe possesses in addition to the usual 3 hairs a short hairy sensory process. In
contrast to Sars’ figure the distance between the Si 2 and Si 3 is 2°5 as long as the distance between
the Sir and 2.

The first pair of legs has the Se Re I just extending beyond the tip of Re Il. On the
anterior surface of Re II, near the lateral margin, 1—2 minute pores are often observed, and at the
outer margin of Re III, somewhat posteriorly, just in the middle, a pore, placed on a minute process
surrounded by delicate hairs, is found. The pes II has a fairly distinct articular surface between
Re I—II anteriorly, but posteriorly it is partly wanting in contrast to pes III—IV, in which it is well
developed. The ¢erminal spine has 40—50 well separated teeth (fig. 3a). On the anterior surface of
the RiIII the usual glandular pore surrounded by delicate hairs is found in the last three pair of
legs; the usual elandular pores at the base of Se Re I—III in the three last pair of legs are not seen,
but they are certainly represented by a number of pores which, as shown in fig. 3a, in the arrange-
ment provides an important character for this species; the “pore” is formed by a chitinous ring, in
the middle of which a generally longitudinal split is seen. In the ReI a single pore and in Re III
three are found in pes II—IV, but in Re II a single is found in pes IV, but 2 in pes II—III.

The lateral outline of the /aévwm is like Sars’ figure Pl. XV, and scarcely different from
Aetidius. The anterior surface of the labrum has, in addition to the usual marginal row of setae
which are fairly slender in the middle and more like granules laterally, in the middle a transverse
row of laterally shorter setae, and in front on each side a group of short setae.

The oral surface of the /abvwm is rather characteristic (fig. 3b). In front of the chitinous
transverse bar behind the median central spot Nr. 3, a transverse row of short setae is found; around
and behind the median spot 4 (S4) short setae are placed in transverse rows. The skin is everywhere,
especially posteriorly, minutely granular. ‘The lateral longitudinal series consists as usual of 5 groups;
the two first groups are placed somewhat longitudinally, are distinctly longer than wide, and consist
of short spinules, most like granules; the groups 3—5 are, in contrast to the two first, less well sepa-
rated, and consist of an inner row of longer and an irregular, outer group of scattered shorter hairs.

The lamina labialis (fig. 3) is in the shape of the dentations somewhat different from that of
Ch. obtusifrons (fig. 2a), and it is almost smooth. The arrangement of the groups of hairs in front of
and behind the lamina labialis I refer to Ch. obtusifrons. About the arrangement of the series of
bristles on the labial lobes, the fig. 3d will give an impression.

£3. Size: Specimen from Thor St. 99 1904 measured 3°66 mm., anterior division 2°65 mm.
urosome IOI mi.

The body seems to be more slender than figured by Sars; the anterior division is 2°6 as long
as the urosome; the fifth thoracic tergite is well distinguished. The first abdominal somite is some-
what assymmetric, and the genital pore is found on the left side; the second somite is three times
as long as the first; the furcal branches, which are almost twice as long as the anal somite, are 1°6

as long ‘as wide.

ee Se ee ee ne ee ee Ce ee ee, ee ee ee en ae Fi ee ieee

COPEPODA 79

The Antennulae are in the main like Sars’ figure; the segments 2425 are almost completely
fused; the segments 8&9 and 10 as well as the 20—21 are almost completely fused on the right side,
but fairly well distinguished on the left side. The segments 8~9 are a little longer than 2, which is
about 1:2 as long as segment 20; the posterior seta of segment 23 is very short. The antennae are
scarcely different from those of the female, in contrast to the mandibulae which, except for the presence
of 2 instead of a single seta in Ri, are completely like Sars’ figure without distinct manducatory plate.
_ The manducatory part of the maxillulae is scarcely developed, and the rudimentary Lil bears a few
short sensory appendages instead of spines; the Li 2 is not developed; the Li3 bears 2 feathery
bristles, the basipodite 3, and the endopodite 9 setae; the exopodite possesses 9 strong plumous setae.
The maxillae are comparatively more slender than figured by Sars, with a number of very short
spinules and_ three proximal knobs. The maxillipeds differ from those of the females by the com-
paratively long Basp. III, which is 17 as long as the second. The first four pair of legs is scarcely
' different from those of the females. Pes V is scarcely different from Sars’ description; the Ri sin
(fig. 3 e) is rather elongate; about the structure of the right and the left exopodite I refer to figs 3g—f.

Y (Stage V). Size: Specimen from Thor St. 72 measured 3°05; anterior division 24 mm.,
urosome 065 mm. Another specimen was 3°65 mm.

The abdomen consists as usual of four somites, of which the second is the longest; the
antennulae are comparatively longer than in the females, and reach to about the end of the second
abdominal somite; the articular membrane between the RiI—II pes II is only indicated by a faint
line. The pes V of the male is, as shown in Pl. II fig. 3h, like that of Gazdius.

YS (Stage IV). Size: Specimen from Thor St. 82 measured 2°16 mm.; anterior division 1°7 mm.;
urosome 0°46.

The shape of the body is like that of the adult specimens, but the abdomen has only three
somites; the number of segments is somewhat reduced in pes IV, as Re II~III and Ri II~III are
mor a less completely fused. Two glandular pores were observed in Re III and one in Re I. The

pes V is rather rudimentary, as seen in fig. 3i.

Variation. In a few specimens from Thor St. 172 °/, 1905, which, except for the less promi-
nent sexual area, were in all other respects like the adult females, a fifth pair of legs, as shown in
fig. 3j, with the right leg the longer, was found. In a specimen from St. 72 (Thor 1905) the left leg
was longer and more slender (fig. 31), and in one from St. 173 (Thor 7/, 1905) fig. 3k the right leg
was again the longer. In two specimens from St. 104 (Thor 74/; 1904), and in one from St. 99 (Thor
22/. 1904), the pes V was like fig. 3e; the last mentioned specimens as well as one from St. 153 (7/5
1905) with pes V dext. > sin. and well developed eggs had the genital somite of female type, but without
distinct receptaculum seminis.

As most of the mentioned specimens were in all respects but the presence of pes V like the
typical ones, and as the mentioned stucture was variable to a degree, it must be regarded as a kind

of abnormity (cf. similar structures in Pseawdocalanus).

Parasites. Ina single adult female from Thor */, St. 285 a stalked parasite was found, attached

to the first basipodite laterally on the anterior surface of the right maxilla; the body consisted of

80 COPEPODA

a chitinous wall and a granular content, and was as a whole not quite unlike a spermatophor.
(text-fig. 17 e).

Occurrence. Of this species the Ingolf Expedition has taken a single adult female *°/¢ 1896
St. 92 64°44 L. N. 32°52 L. W.

The Thor Expedition has gathered the species, fairly common, at several stations, most often
in deep hauls. -

Thor "/, 1904. St. 153. 65°20 L. N. 27°12°5 L. W. Yt. 800 M. Wire 1 £2; 1 fd; 1 yh (V).
9/, 1904. St. 178. 63°08 L. N. 21°30 L. W. Yt. 750 M. Wire 1 £9.
5 1904. St. 285. 62°49 L. N. 18°46 L. W. Yt. 500 M. Wire 17 £9.
11/, 1904. St. 183. 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 15 £9; 2 fdt; 2 yc (V).
24/, 1904. St. 104. 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 8 £9; 1 yo (V).
29/3 1905. St. 164. 61°20 L. N. 11°00 IL. W. Yt. 300 M. Wire 2 f9.
22/, 1904. St.gg. 61°15 L.N. 9°35 L. W. Yt. 1700 M. Wire 2 £9; 2 fd.
Yt. goo M. Wire 3 f9.
12/, 1904. St. 78. 61°08 L. N. 9°28 L. W. a A
23/, 1905. St. 124. 61°04 L. N. 4°33 L. W. Yt. 100 M. Wire 1 f9.

Outside the Ingolf area the S/S. Thor has gathered the species at the following stations.

Thor %5/6 1905. St. 82. 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 1 £9; 1 y?(V).
800 M. Wire 2 £9; 1 yh (V); 1 yo (IV).
20/6 1905. St. 88. 48°00 L.N. 8°30 L. W. Yt. 300 M. Wire 4 £9; 1 y2(V); 2 yo (V).
8/6 1905. St. 72. 57°52L.N. 9°53 L. W. Yt. 1500 M. Wire 75 f? (one with spermatophor)
1£38; 4yd(V); ry? (V).
9/, 1904. St. 294. 57°54 L.N. 7°38 L. W. 9 f.
1/, 1905. St. 167. 58°42 L. N. 6°13 L. W. Yt. 1500 M. Wire 17 £2; 1 yh (V); 2 y? (V).
®/, 1905. St. 172. 57°33 L.N. 4°26L.E. Yt. 300 M. Wire 121 £2; 4 fd; 5 yo (V).
7/y 1905. St. 173. 57°52 L.N. 8°or lL. E. Yt. 600 M. Wire 3 f?.
Yt. 300 M. Wire 4f¢.

Distribution. The above mentioned localities affirm the conclusion arrived at by Farran at the
base of the records in the literature “that Chiridius armatus is a permanent inhabitant of the North-
East Atlantic, the Norwegian Sea south of 65° N., the Norwegian Channel and the Skagerak, at depths
of from 300 to 2000 metres, and is also indigenous to all the deeper Norwegian fjords.” It has been
taken by the Monaco Expedition; the records of this species from the west coast of Greenland and
from the North Polar Basin refer, as shown by Sars, really to Ch. obtusifrons.

According to Damas and Koefoed it has been taken at the following two stations by the
Duc d’Orléans. Viz: St. 14 9/, 1905 80°17 L. N. 5°40 L. E. between 340 and 600 meters (f? with
ovisacs) and St. 23, 7/, 77°25 L. N. 4°03 L. W. between 480—640 meters; as, however, nearly related
species exist, which have probably been confounded with Ch. armatus now and then, these localities
ought to be accepted with due reservation.

COPEPODA 81

Remarks. In spite of the small differences enumerated in the description, I do not doubt that
this species is identical with that described by Sars from Norway, and with that which Wolfenden has
described under the name of Psewdaetidius from the Feroe channel. According to my investigations
the size of the specimens varied from 36 to 44 mm., the biggest being those from northern regions;
Farran’s (1905) specimens measured 3°3—3'5 mm., and even 2°65; these small specimens possibly belong

to another species.

17. Chiridius nasutus n. sp.
(Pl. II fig. 4a; text-figs 18a—e).

1905. pars? Chiridius armatus Boeck. Farran.

Description. £9. Size: Specimen from St. 167 2°88 mm.; anterior division 2-19 mm.; urosome o'69.
The shape of the body is in the main like that of the preceding species, but somewhat more
slender (text-fig. 18a). The insertion of the antennulae is apparently better removed from the tip
and the rostral spines, which are somewhat longer E

and basally swollen, and directed more forwards
(text-figs 18 b—c). The anterior division is just three
times as long as the abdomen. ‘The genital somite
(text-fig. 18d), which has a receptaculum seminis like
that of Ch. armatus, is about 1°5 as long as the third
and 17 as long as the fourth somite; the furcal rami
are 1°7 as long as wide and 1°7 as long as the anal
somite; the last segment is about half as long as
the third one. The antennulac, which extend some-
what beyond the end of cephalothorax, but scarcely to
the end of the abdominal somite, have the segments

24 and 25 well defined; the measurements differ only a d re

in minor details, as the segment 20 is a little longer Text-fig. 18. Ch. nasutus n. sp.

a. Head in dorsal view X 16. b. Rostrum from below X 150.
c. Head in lateral view X 60. d. Genital somite etc. 60.
21, and as the segment 23 is scarcely 1r as long as e. Pes IV dext. in anterior view with abnormal rami X 150.

than 8~9, as the segment 18 is a little longer than

24. The appendages are like those of Chzridius

armatus, but the Sp. of the segment 23 extends somewhat beyond the end of the segment 25. The
antennae are like those of the preceding species, but the exopodite is 1°5 as long as the endopodite.
The mandibulae and maxillae are scarcely different, and the maxzllulae only by the smooth anterior
surface of the third basipodite. In the mamzllipeds the third basipodite is 1°5 as long as the second,
and 2°2 as long as the endopodite. The legs are only in minor points different from those of C2.
armatus; the Se of Re I in the first pair of legs extends a little beyond the end of the second seg-
ment, the articulation between the Re I and II of the second pair of legs is well developed anteriorly
as well as posteriorly, and its ¢erminal spine has 30—40 spinules (fig. 4a). A curious difference is
found between this species and Chiridiws modestus as well as armatus in the arrangement of the

glandular pores; in the number of the pores it is, as shown in fig. 4a, like Ch. modestus, as a single pore

The Ingolf-Expedition. III. 4. +:

82 COPEPODA

was found in the three segments of the exopodites in the three last pair of legs, but in the position
of the pores, especially in Re I—II, it is most like Ch. armatus, as these are placed on the anterior
surface, well removed from the lateral margin.

Occurrence. This species was taken by the S/S Thor at the following 3 stations viz:

™/, 1904. St. 183. 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 £9.
8/6 1905. St.72. 57°52L.N. 9°53 L. W. Yt. 1500 M. Wire 2 f9.
tl, 1905. St. 167. 57°461L.N. 9°55 1. W. Yt. 1500 M. Wire 2 f2.

Remarks. This species, which on account of its small size, the prominent rostrum, and the
curious arrangement of the secretory pores is well distinguished from Cz. armatus, is certainly new
to science, as in the literature I have only found a single reference to a species of the Ch. armatus

type of a size of 2°65 mm. (viz. Farran 1905 p. 34).

18. Chiridius modestus n. sp.
(Pl. II fig. 5; text-figs 19 a—c).

Description. f?. Size: Specimen from St. 183 measured 369 mm.; anterior division 2°70 mm.,

urosome 099.
The rostral spines are longer and more prominent than in Ch. armatus, but less so than in
nasutus (text-fig. 19 b), The outline of the head is anteriorly not fairly rounded as in Ch. armatus, but
distinctly produced (text-fig. rga). The frontal organ is prominent,

b
and the distance between it and the base of the rostrum is short

| and straight, not slightly concave as in the two other species. The
cephalothorax, which is 2°5 times as long as wide, is scarcely 3

i times as long as the urosome. The genital somite, which has a
ike. receptaculum seminis of the usual structure, is about 1°3 times as

F “OY long as the third somite, and 1°7 as long as the fourth (text-fig. 19 c);
ws the furcal rami are r6 as long as wide, and 14 as long as the

anal somite, which is a little longer than the furca; the latter
somite is scarcely half as long as the third one.

The antennulae, which extend somewhat beyond the end
Text-fig. 19. Chiridius modestus n. sp.
a. Head in dorsal view X 16.

b. Head in lateral view 60. pendages and the measurements are scarcely different from those
c. Genital somite etc. 60.

of the thorax, have the 24—25 segments almost fused. The ap-

of Ch. nasutus. The antennae have the exopodite 14 as long as
the endopodite; the Re I has, inwards, a conical process, but no seta, and the Re II has a medial and
a terminal seta placed on a small protuberance, in addition to a basal protuberance without seta. The
mandibulae and maxillae do not show any features of interest, and the maxzllulae only differ from
those of Ch nasutus by slightly developed spinulation of the anterior surface of the Li 3. The third
basipodite of the mazillipeds is 14 as long as the second, and 24 as long as the endopodite; its 2
proximal setae are placed near to each other with the articular membranes confluent. The Se Re I
in the first pair of legs extends distinctly beyond the end of the segment. In the second pair of legs

Se ee ee oy ee

COPEPODA 83

(fig. 5 a) the terminal spine has about 80 densely placed, partly fused, spinules; in other respects, except
the arrangement of pores, which, except for the more medial position is like that of Ch. obtusifrons
ete, the legs are like those of preceding species.
Occurrence. The S/S. Thor has gathered a few specimens of this species at the following
two stations.
21/6 1904. St. 154. 65°27 L. N. 27°10 L. W. Yt. ? Wire 3f9.
™/, 1904. St. 183. 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 2 f9.

; Remarks. This species, which seems to stand between the species of Chirzdius without rostrum
and Ch. nasutus, is well characterized by the shape of the rostrum and the position of the glan-

dular pores.

1g. Chiridius obtusifrons G. O. Sars.
(Plate II figs. 2a—b; text-figs 20a—e).

1897. Pseudocalanus armatus Boeck. Vanhéffen, p. 279, fig. 6. | 1907. Chiridius armatus Boeck. Vanhdffen, pp. 519—521.
1goo, Chiridius armatus Boeck. G. O. Sars, pp. 29—30, pl XVII. | 1908. _ obtusifrons G. O. Sars. v. Bremen, pp. 34
1902. _ _ — Mrazek, pp. 521—22. —35, fig. 37.
1903. Chiridius obtusifrons n. sp. G. O. Sars, pp. 29—30, pl.17. | 1909. nec. Chiridius? obtusifrons G. O. Sars. A. Scott, p. 43,
1904. = — G. O. Sars. Wolfenden, p. 131. . pl. XLIV figs 1—3.
1904? _ Vanhéffeni n. sp. Wolfenden, p. 117, pl. IV | 1913. pars. — armatus Boeck. Stephensen, pp. 316—317.
fig. 23.

1907. = obtusifrons G. O. Sars. Koefoed & Damas,

i p- 408.

Description. £9. Size: Specimen from Thor St. 214 measured 4:39 mm.; anterior division 3°12

mm., urosome 1°27 mm. Sars’ specimens measured 472 mm. and VanhOffens 4'5 mm.

The shape of the body is as figured by Sars . ; ‘
(cf. text-fig. 20a). The articular membrane between
the head and first thoracic tergite and between the .
fourth and fifth thoracic tergite (except in the middle) ] AT
is often wanting; in the articular membrane be- : : y i
tween the last thoracic and the first abdominal , :
somite chitinous lists of a rather curious structure
are found (text-fig. 20 c). According to most authors

no rostrum is observed; in several specimens, ho-
wever, the rostrum was represented by a very short
spine, sometimes showing trace of bifurcation as a
median line, when observed from beneath. The
anterior division is 2'4 as long as wide, and 274 as
long as the abdomen. The genital somite, which

has a receptaculum seminis of a similar structure ¢

as in Ch. armatus, but more slender, is 1°2 as long Text-fig, 20. Chiridius obtusifrons G. O. Sars.
a. Cephalosome X 9. b. Genital somite in lateral view X 31.

as the fourth somite; the furcal rami are almost c. Genital somite in dorsal view < 33. d. Anal somite etc.

twice as long as wide (text-fig. 20 d). in dorsal view < 60, e. (Downwards to the left) pes II in
: anterior view X 60. f. (In the middle above) pes III in an-
The antennulae, which almost extend to the terior view < 60.

i pe

84 COPEPODA

posterior end of the genital somite, have the 24 and 25 segments fairly well separated; the segments
2 and 89 are of equal length, and a little longer than the segment 20; the segment 18 is distinctly
Ir as long as 21, and the segment 24 is a little longer than 23. The posterior seta of the segment
23 scarcely extends to the tip of the segment 24. The antennae have the exopodite almost twice as
long as the endopodite, and the third basipodite of the mandibulae has the Si 1 shorter than figured
by Giesbrecht (Taf. 14 fig. 17). The maxillulae, maxtllae and the maxillipeds are scarcely different
from those described by Giesbrecht; a small pointed process, placed behind the articular cavity of
the maxillipeds, is better developed than in preceding species (text-fig. 20a). The first pair of legs is
like Sars’ fig., but the Se Re I extends a little beyond the end of the Re II. In the second pair of
legs (text-fig. 20 e) no trace of articulation was found between Ri I—II, neither anteriorly nor posteriorly;
the articular membrane between Re I—II is anteriorly indicated by a faint line. Glandular pores
are found at the base of the respective Se of Re I—III in the last three pair of legs; the. articular
membranes between the Re I—II in pes III—IV are scarcely better developed than in the second
pair of legs, but the articulation between Ri I—II is marked not only by a lateral incision as drawn
by Sars, but also by a faint line anteriorly (text-fig. 20 f).

The structure of the /aérum is in most respects like that of Ch. armatus; the most interest-
ing differences are found at the oral surface viz: the wanting transverse row of spinules behind
the median circular spot Nr. 3, and the lateral group of spinules anteriorly which is divided into a smaller
anterior and a bigger posterior portion. The /amzna labialis (fig. 2a) consists posteriorly of a chitinous appa-
ratus which is subdivided into a median and two lateral clumsy teeth, the posterior margin of which is
somewhat striated; the lamina is gradually sloping anteriorly, and overlapped by the slightly concave
posterior margin of an almost semicircular chitinous plate. In front of the lamina labialis we observe
on the posterior wall of the pharyngeal cavity in the middle a smooth longitudinal area, and on each
side of this a minutely granular area, as seen in fig.2a. Laterally a series of fairly slender setae,
which aré. situated on a chitinous lists, apparently a continuation of that supporting the serrula
6-dentata, is found. Behind and medially, a longitudinal series of about 20 more slender setae; this
series reaches only a little beyond the anterior limitation of the lamina labialis. The number of the
serrulae behind the lamina is three, arranged as seen in fig. 2a.

The number of series of hairs behind the labial lobes etc. is in the main like that of Gaidius
(cf. fig. 7f). The series lateral 1 seems to be wanting, series lat. 2 consists of about 30 short
delicate hairs which are anteriorly placed in a single longitudinal row, and posteriorly in an irregular
group; the series lat. 3 has posteriorly an oblique row of short hairs, on the medial side of which
we find an area consisting of about 20 short bristles, and anteriorly one or two short rows, one of
which is ¢gontinued as a long row to the end of the labial lobe. The series lat. 4 is medially placed
transversely with backwards directed convexity, as seen in fig. 2a; laterally to this, and probably be-
longing to it, a triangular group of densely placed hairs is found. The series lat. 5 is represented by
a group of densely placed short hairs, which are placed in a triangular area, pointed in front. The
connection between the two last series and the hairs on the lateral lobes was not made out.

Y (Stage V). Size: Female from St. 154 measured 3:08 mm.; anterior division 2:3 mm.; uro-

some 078 mm,

ey i ie >

ee ee fee ete ee er eee ee

COPEPODA 85

The shape of the body is in the main like that of the adult, but the articulation between the
head and the first thoracic tergite was complete at least in a single specimen; a well marked fifth
somite bearing the lateral spines was found. The abdominal somites are as usual four. The male
differs from the females by the presence of a fifth pair of legs without any endopodite, corresponding
to the structure in the adult males (PI. II fig. 2b).

Occurrence. The Ingolf Expedition has curiously enough not gathered any specimen of this

species, but the Thor has taken it at the following stations.

2t/, o4 St. 154 65°27 L. N. 27°10 L. W. Yt. 800 M. Wire 85 £9, 1 y?(V).

22/, o4 St. 214 67°19 L. N. 17°55 L. W. Yt. 800 M. Wire 67 {£2 (one with spermatophor), 1 y9.
23/, 04 St. 216 66°15 L. N. 12°13 L. W. Yt. 600 M. Wire 1 f9. :

9, 04 St.70 63°35 L.N. 6°20 L. W. Yt. 100 M. Wire 12 f9.

23/, 05 St. 124 61°04 L.N. 4°33 L. W. Yt. 100 M. Wire 1 f9.

The Danish East Greenland Expedition 1900 has gathered the species three times.

4/, 1900 3 p.m. 79°09 L. N. 4°36 L. W. Vertical net 300—o 1 f9.
8/, 2 p.m. 74°09 L. N. 11°31 L. W. -- 400—o 2 f9.
4/, 12 p.m, 61°06 L. N. 16°26 L. W. F. 392 2 £9.

Distribution. Nansen’s North Polar Expedition found this species rather abundantly from
the surface down to a depth of 300 meters. By the S/S Michael Sars it has been taken twice in the
open sea about midway between Iceland and Norway. According to Wolfenden this species occurs
sparingly in the cold underwater of the Feeroe channel. By the Duc d’Orléans this species was found
at eleven stations, most often between 300 and 600 meters, as far north as 78° N., as far east as 5° L. E.
and as far west as 16° L. W. In Lille Karajakfjord it was taken by Vanh6ffen on the west coast of
Greenland.

Taking into consideration the new localities enumerated above, it seems right to regard the

species as characteristic of the deeper layers of the Arctic seas.

Remarks. The male which Wolfenden has described as Ch. Vanhéffeni is certainly identical
with that discribed by G. O. Sars as Ch. obtusifrons. ‘The species, which A. Scott with doubt refers to
this species, does certainly not belong to it, on account of its smaller size and more robust body, not

taking into consideration the distribution.

20. Chiridius gracilis Farran.
(Text-figs 21 a—d).

1905. Chiridius Poppei Giesbrecht. Farran, p. 35. 1909? Chiridius? gracilis Farran. A. Scott, p. 42, pl. XI figs 1—3.
1908. a gracilis n.sp. Farran, pp. 30-31, pl. II figs | rrr? — polaris n. sp. Wolfenden, pp. 211-212, taf.

I--3. XXIV figs 9—12, text-f.6a—b.

Description. Size: 2°69 mm.; anterior division 2°00; abdomen o69 mm. Farran’s specimens

measured 2‘4—2.8 mm.

86 COPEPODA

The shape of the body is like Farran’s description; the anterior division is 2°9 as long as
the abdomen; the furcal rami are 14 as long as wide (text-figs 21a—b). The axtennulae differ from
those of Ch. obtusifrons by the 20 segment, which is a little longer
than the second, which is again longer than segments 8&9. The
Si of the third basipodite of the mandibulae is longer and thicker
than that of Ch. obtusifrons, but shorter than that of Ch. Poppet.
In the other mouth appendages scarcely any difference was ob-

served. In the first pair of legs the Se Re I does not extend to

: the end of the segment. The segmentation of the legs is better
| developed than in Ch. obtusifrons, as shown by Farran (text-figs
b 21 c—d).

d Occurrence. Though the Thor has only taken 3 f? (of
Text-fig. 21. Chiridius gracilis Farran.
a. Genital somite in dorsal view X 60.

which one with spermatophor) §/s 1905 St. 72 57°57 L. N. 9°53

b. Furca X 60. L. W. Yt. 1500 M. Wire, I think that this species belongs to the
c. Pes II sin in anterior view X 60. NS
d. Pes Ill sin in atiterior view X 60. fauna of the region explored by the Ingolf Expedition.

Remarks. This species is according to Farran fairly
common on the west coast of Ireland; its range was from 280 to rooo fathoms, I think it is extremely
doubtful whether the species which A. Scott refers to this species, from the Malayan Sea, really is identical
with the Irish species. I think that Farran is right in regarding it as a species which forms a con-
necting link between the much smaller Ch. Poppet and the much bigger Ch, obtusifrons, of which the
former is a distinct Arctic and the latter a Mediterranean form.

As the females belonging to the Chiridius, as Giesbrecht defined it are very much alike, a
thorough investigation of the differences between the existing species viz. those from the Siboga
expedition, the three mentioned above and Cz. polaris Wolf. (p. 212), which is very nearly related to
if not identical with Ch. gracilis, is needed.

21. Aetidiopsis rostrata G. O. Sars.
(Pl. II figs 6a—b; text-figs 22 a—d).

1903. Aetidiopsis rostrata n.sp. G. O. Sars, p. 160, supplement | 1907. Aetidiopsis rostrata G. O. Sars. Koefoed & Damas, p. 409.

pls. IV—V. 1908? Faeroella multiserrata Wolf. Farran, p 29.
1904? Faeroella nrultiserrata n. sp. Wolfenden, p. 117, pl. IX | 1908. Aetidiopsis rostrata G, O. Sars. v. Bremen, p. 33, fig. 35.
figs 26—28. 1909.Nec. — -- — A. Scott, pp. 4o—41, pl.
1906? — — Wolf. Pearson, p. 13. V figs 13—24.

Description. f9. Size: Specimens from Thor St. 214 measured 38 mm.; anterior division 2°76
mm.; urosome 104. Other specimens measured 34 and 399. Sars’ specimens measured 44 and Wolfen-
den’s 3°54 mm.

The shape of the body is like Sars’ figure. The rostral spines (text-fig. 22a) are comparatively
shorter, and in shape somewhat different from Sars’ figure; the frontal organ is very prominent. The
articular membrane is distinct not only dorsally, but also laterally between the head and the first
thoracic somite. The lateral spines of the thorax (text-figs 22b) scarcely reach the middle of the
genital-somite. The abdomen is in most specimens at least one third of the length of the cephalo-

COPEPODA 87

thorax, but in others it is scarcely one third. The comparative length of the abdominal somites and
the furcal rami are 32 — 24 — 18 — 11 — 16; the furcal rami are 16 as long as wide. The receptacula
seminis are in most specimens well developed, and of similar shape as in Ch, obtusi/rons (text-figs 22b—c).

The antennulae, which have the segment 24 and 25 well separated, reach about to the end
of the third abdominal somite; the segment 2 is 12 as long as 8~9, which is a little shorter than
the segment 20; the segment 21 is about as long as 18, and the segment 23 is rr as long as the 24.
_ The appendages are like those of Ch. obtusifrons, but a distinct “Aestetask” is found in segment 7; the
posterior seta of segment 23 reaches distinctly beyond the end of segment 25. The aztennae are like
Sars’ figure, with the Re 14 as long as the Ri; the setae of Re I—II are arranged as described in
Ch. modestus. The mandibulae are like Sars’ figure. The maxtliulae are in main features, especially
in the number of setae, like Ch. armatus; the maxillae are .
scarcely different from Sars’ figure, but differ from those of
mentioned species by a small depression in the middle of
the exterior margin of the first basipodite, which seems to
be connected with a wide chitinous sac. The third basipodite
of the maxzillipeds, is 15 as long as the first and second seg-
ments and almost twice as long as the endopodite.

In the first pair of legs the Se Re I extends
distinctly beyond the end of Re II. The second pair of |
legs has the first basipodite greatly enlarged inwards; the
articulation between Ri I—II is wanting anteriorly; glan- 5s d
dular pores are present at the base of the Se in Re I—III; Text-fig. 22. detidiopsis rostrata G. O. Sars.

e “ : a. Head in lateral view X 60. b. Genital somite
the St has 58 spinules (in Sar’s figure 35 only). The fourth jn tateral view X60. c. Genital area from below

pair of legs differs from that of the three first pairs by ESAS T RAY Set: M poet. xigwe, 16 8.
wanting marginal row exteriorly of the second basipodite; its structure is in most features like Sars’
figure, and the St has about 60 spinules (text-fig. 22 d).

The anterior surface of the /adrwm was like that of Ch. armatus, but differed by the wanting
lateral irregular group of hairs in front of the transverse series. The oral surface has the hairs in
the three first groups, especially the third, somewhat differently arranged, as seen in fig. 6a; the groups
4—5 are more irregular than in this species. The damina labialis is, as seen in fig. 6b, in most respects
similar to that of Ch. armatus; the inner longitudinal series in front of the lamina was not observed.
The longitudinal series of hairs upon and behind the labial lobes are in most features, especially in

series lateral IV—V, like those fully described in Ch. obtusifrons.

Occurrence. The Ingolf Expedition ™/, 96 630 p. m. St. 105 65°34 L. N. 7°31 L. W. closing
net 700 fathoms has taken a single adult female, and the S/S Thor has gathered it at the following
three stations,

20/6 O4 St. 153 65°20 L. N. 27°12'°5 L. W. Yt. 800 M. Wire 1 f9.
21/6 04 St. 154 65°27 L. N. 27°10 L. W. Yt. 800 M. Wire 3 f9.
22/, o4 St. 214 67°19 L. N. 17°55 L. W. Yt. 800 M. Wire 6 f9.

88 COPEPODA

Distribution. This species was taken twice by S/S Michael Sars between Jan Mayen and Fin-
marken at a depth of from 500 to 1000 metres. According to Koefoed and Damas the species is
found “a) dans la mer du Grénland: de 60 jusqu’ a 1800 métres au moins, b) dans la mer de Noryége:
jamais observé 4 moins de 400 métres” (p. 409). By the Duc d’Orléans it was gathered at ro stations
as far east as 2°40 L. E. at 79° L. N., and as far west as 15° L. W. at 78° L. N. near the east coast of
Greenland. The expedition has at the most northern station 1/, 1905 taken adult males as well as
females and young ones. According to Wolfenden his Faeroella multiserrata “is not uncommon in
the deep water of the Fzeroe channel, and has been traced by the writer as far south as Valentia in
Ireland” (p. 117). This species is, according to Farran, “occurring not uncommonly from 400 to 1000
fathoms” off the west coast of Ireland.

Remarks. I do not doubt that the specimens which I have examined ought to be referred
to Sars’ species, in spite of the smaller size, the shorter rostral spines, the lateral spines which scarcely
reach the middle of the genital somite, and the comparatively longer abdomen; from Wolfenden’s
very imperfect description it differs by the well marked segmentation between the head and first
thoracic tergite, by imperfect segmentation of Ri pes II, and by more coarsely spinulated terminal spines
of the legs.

Though Sars (cf. Farran p. 20) has accepted Wolfendens species as distinct from his own,
and in spite of the different distribution, I am fairly convinced that they belong to the same species;
the southern variety has sometimes comparatively few dentations in the St pes II (Farran has found
32 only). Further examination and comparison of the different forms are needed before the question
can be solved. It is to be regretted that neither Wolfenden nor Damas & Koefoed, who have
examined the males as well, have given any description of them.

If Scott’s figure of the antennulae of his A. rostrata Sars is correct, the Sp. of the segment
23 does not reach the end of the segment 24, and a new species ought to be established.

Wolfenden has later on established 2 new species /aeroella minor and antarctica (1911 p. 214);
it is remarkable that this author does not accept Sars’ name, which without doubt has the priority.
That the species are cogeneric does not seem to be doubtful; whether the genus is quite natural is very

doubtful. To solve this rather vexed question I have not sufficient material of the different genera.

22. Udinopsis armatus Vanhdffen.

1895. Bradyanus armatus n.sp. Vanhdffen, p. 322. 1907. Udinopsis armatus Vanh. Vanhdffen, pp. 517—519, taf. 21
1897. — — Vanh. Vanhdffen, p. 280, fig. 17. fig. 24.
1902. pars. Bradyidius armatus Vanh. Mrazek, p. 521. 1908. Bradyidius similis G. O. Sars. v. Bremen, p. 32, fig. 32.
1903. Udinopsis similis n. sp. G. O. Sars, p. 34, pl. XXL 1913. Udinopsis armatus Vanh. Stephensen, p. 317.

This species, which has not been secured by any of the expeditions, has been mentioned from
“Lille Karajak Fjord” on the west coast of Greenland, and Sars has found it in the inner part of the
Stavanger Fjord, where “it only occurred close to the ground”, “the depth ranging from 50 to 100
fathoms”.

This species is not identical with Bradyidius armatus Giesbr. of Scott, Giesbrecht-Schmeil
and Wolfenden. Stephensen has wrongly given Bradyidius armatus v. Bremen as partly synony-

mous with it.

ee

COPEPODA 89

23. Gaidius tenuispinus G. O. Sars.
(Pl. II fig. 8a; pl. III figs 2a—n; text-figs 23 a—j).

1goo. Chiridius tenuispinus n. sp. G. O. Sars, p. 67, pl. XVIII. 1907. Gaidius tenuispinus G. O. Sars. Vanhéffen, pp. 521—522,
1902. Gaidius tenuispinus G. O. Sars. Mrazek, p. 512. taf. 21 fig. 27, taf. 22 fig. 33.
1902. — borealis n. sp. Wolfenden, p. 365. 1907. — — G. O. Sars. Koefoed & Damas, p.408.
1903. — tenuispinus G, O. Sars. Norman, p. 136. 1908. = -- —.. Farratt, '‘p. 32.
1903. Chiridius tenuispinus G. O. Sars. G. O. Sars, pp. 30—31, | 1908. - _- _ v. Bremen, p. 36, fig. 39.
pl. XVIII. 1g09.Nec. — _ similis Th. Scott. A. Scott, pp. 51—52, pl. VII
1903. Gaidius tenuispinus G. O. Sars. G. O. Sars, p. 162, pl. VI, figs I—11.
suppl. Igil. — tenuispinus G. O. Sars, Farran, p. 97.
1904. ?Gaidius pungens Giesbr. Wolfenden, p. 131, pl. 1X fig. 43. | 1911? -- a — Wolfenden, p. 223, figs
1905. Chiridius tenuispinus G. O, Sars. Th. Scott, p. 223. Ir a—b.
1905. Gaidius tenuispinus G. O. Sars. Farran, p. 33. 1913. —— — — Stephensen, pp. 315
1906. - _ i _ Pearson, p. 13. —316.

Description. {9. Size: Specimen from Thor St. 70 measured 3°84 mm.; anterior division 2°94 mm.;
urosome o:g90 mim. Two specimens from Thor St. 285 measured 2°6-+-062 — 322mm. and 29+ 08
= 37 mm.; specimens from Thor St. 183 measured 2°77 +07 = 34mm. Sars’ specimens measured 38
and Wolfenden’s 38 (1904) and 3°25 (1911) mm. Vanh6ffen’s specimens 3:9 and Farran’s (1905) 3:2 mm.

The shape of the body is scarcely different from Sars’ figure, and no trace of segmentation
between the fourth and fifth thoracic somite was observed; the lateral spines of the thorax are distinctly
set off, and extend almost to the end of the genital somite (text-fig. 23a). The rostrum is not, as set
forth by most authors, undivided, but shows as seen in fig. 2a (Pl. III) trace of bifurcation.

The length of the abdomen, compared to that of the anterior division, varies from about */,
to '/,, The genital somite, which as seen in fig. has a short and well marked receptaculum seminis,
well distinguished from the stalked one in Chzridius, is somewhat deeper and wider than long, and
16 as long as the third somite. The furcal rami are 1°6 as long as wide and a little wider than the
anal somite is long.

The antennulae reach to about the end of the third abdominal somite and have the measure-
ments distinctly different from those of G. drevisfinuws on account of the shorter distal segments; the
segment 2 is 12 as long as 8~9, which is almost 1-3 as long as segment 13 and only a little shorter
than segment 20; the segments 19 and 22 are almost of equal length, and almost rz shorter than
segment 2. The appendages are like those described by Giesbrecht in Gaetanus armiger with
“Aesthetasken” in segments 3, 4 and 6 and Spr. in segment 13; the posterior seta of the segment 23
is ringed, and about three times as long as the segments 24 and 25, which are well separated.

The antennae have the Re 13 as long as Ri; the Ri I is distinctly twice as long as Re II;
this, is about twice as long as Re I, and about twice as long as Re III—VI, and about 2/; as long as
Re VII. The Re II has the short Se 2 placed on a rather prominent process, (PI. III fig. 2e), like
that found in Giesbrecht’s fig. 19 Taf. 14 of Gaetanus armiger, and the Se 3 is somewhat longer.
The mandibulae differ from Sars’ figure by two slender Si of the third basipodite, and are in main
features like those in Giesbrecht’s G. armiger. The maxillulae are rather elongated, like Gies-
brecht’s figure of Gaetanns miles (Taf. 14 fig. 21); the LiI possesses on the anterior surface about 10
fairly strong teeth, and on the posterior surface near the base of S 11 about 10 similar ones; the Li I

has 4 setae, and the Li III 5-+-a sensory lobe and anteriorly a fairly strong spinulation, the Basp. III
The Ingolf-Expedition. III. 4. 12

go COPEPODA

has 4 Sp and 1 Sa but no spinulation anteriorly; the RiI has 3 Sa-+1 Sp, the Rill has 3Sa-+1Sp
and the RiIII 5 S. The exopodite has 11 setae, and the Le has 7 long + 2 shorter ones. The maxillae
are very characteristic by the strongly and suddenly convex outer margin of the basipodite, with a
short concavity in the middle (text-fig. 22 b); the lobe I possesses a quite rudimentary spinelike Sp. 1
and a Sp. 2, which it about twice as long as the lobe itself; the strong spine of lobe IV is somewhat
longer but scarcely stronger than that of lobe V. The third basipodite of the ma-xillipeds is 1-2 as long
as Basp. I—II and three times as long as Ri; the exterior margin of the second basipodite has no trace
of lamina, and its fourth lobe bears 3 hairs and a sensory process (fig. 2c Pl. III).

The frst pair of legs has the articulation between Re I and II indicatad by a faint line

anteriorly, and sometimes a small incision laterally; the Se Re I is wanting; the St has the usual

b d f

¢ i

Text-fig. 23. Gazdius tenuispinus G. O, Sars.
a. 9, Abdomen in lateral view 33. b. Maxilla sin. in posterior view. c. Pes IV sin. in posterior view x 82. d. GC. Pes
V sin. X 140. e€. Maxilla dext. in anterior view to show position of parasites x 60. f and g: the same parasites 150.
h—j. Contorted bodies attached to the body-wall x 4oo.

characteristic structure (Pl. III fig. 2d). The articulation between Re I and II in pes II and Ri I and
II is as shown in Sars’ figure well developed; the St has 25 teeth. The fourth pair of legs has
the Re III three times as long as wide and the St. has 25 teeth, partly armed with accessory ones; the
first basipodite has the usual marginal hairs substituted for by 30—40 stiff thin lamellous bristles,
which are placed in about 5 rows along the inner margin, and in 2—3 parallel ones on posterior surface,
the more posteriorly the more distally placed. The arrangement and number of the glandular pores

in pes I—IV are as in Ch. obtusifrons.

The lateral view of the /abrvwm is like that of Chiridiws, but the different parts are less
prominent. The oral surface of the labrum (Pl. III fig. 2e) is, as seen by comparing figures,

distinctly different from Gazdius brevispinus; the five groups, as well as the sixth more transversely

COPEPODA gI

placed one (not seen in fig.) are well separated; the setae around the median circular spot Nr. 4 are
well developed.

The /amina labialis is almost smooth, but in other respects scarcely different from fig. 7f (Pl.
II), and the area in front of it is most like fig. 5e Pl. III. The longitudinal lateral series of hairs
placed behind the lamina labialis are in details somewhat different from those of G. drevispinus; the
3 posterior groups of the third series are better separated, and without direct connection with the
anterior part; the proximal and distal groups of the series V seem to be fused.

fg. Size of specimen from Thor St. 183 was 3:01 mm.; anterior division 2°3 mm., urosome 071.

The shape of the body is scarcely different from Sars’ fig. Pl. VI (supplement). The rostrum
is fairly long and shows, terminally, trace of bifurcation (Pl. III figs. 2 f—g).

The antennulae have the segments 89 partly fused with 10, and the segments 12 and 13 with
14; the segments 20 and 21 and 24 and 25 are completely fused; the appendages are scarcely different
from those of Aetidius armatus (cf. Giesbrecht Taf. 14 fig. 15). The measurements differ from those
of the female by the segment:22, which is rr as long as segment 17 and 1:2 as long as segment 2. The
structure of the aztennae is in most respects like that of the female, but the Si 2 of Re II is not
placed on a small process. The manducatory portion of.the mandibulae (cf. fig. 1d) is even more
thin-skinned than in G. drevispinus, but has rudimentary teeth; the third basipodite has no setae,
and those of the exopodites and endopodites are better developed. The maxdllulae differ from those
of G. brevispinus (fig. 1 e) by a fairly long Li 2 with a number of rounded sensory organs. The maxzillae
(Pl. III fig. 2h) are small, thin-skinned organs, which in the main preserve their original shape;
the exterior margin of the basipodite has no convexity; the inner surface possesses an indistinct
number of short partly fused lobes, the setae of which are more or less transformed into thin-skinned
more or less setiformed appendages with a swollen base; the Ri has a few setae of usual form. The
two first segments of the maxillipeds possess only the fourth lobe.

The frst pair of legs has,.as shown in fig. 1 g, the Se Re II represented by a minute seta, and
the St. is as usual in the male almost straight (Pl. III fig. 2i); the second to the fourth pairs of legs
are scarcely different from those of the females, except by the smooth inner margin of the second basi-
podite of the fourth pair of legs. The f/th pair of legs is on the right side in the main like Sars’
figure; the Ri (Pl. III fig. 21) is distally swollen and contains clear alveolar structures; the Re I (III ?)
has in most specimens a lateral protuberance, and shows trace of segmentation (fig. 2m); the Re
II has inwards a lamelli-form process which surrounds a shallow cup facing backwards and outwards (fig.
2n, cf. fig. 1j); the Re III is elongate and curved with a terminal hooked hairy process. The left leg
(text-fig. 22d) appears more slender than in Sars’ figure; the Ri which shows a trace of segmentation
is long and slender, distally somewhat enlarged and bearing a short hair; the Re 2 has inwards a hairy
protuberance (fig. 2j), and the Re 3 is very elongate with a distal fairly long Se and a St. (fig. 2k).

Y (St. V). Size of female from St. 70 3:15 mm.; anterior division 2°51 mm., urosome 064.

The shape of the body, except for the usual segmentation of the abdomen, is as in the female,
the antennulae extend almost to the end of the abdomen. The mouth appendages are scarcely in
any features of interest different from those of the female. The articulation between Ri I and II of

pes II is less developed than in the female; the glandular pores were scarcely different. Along the
13°

92 COPEPODA

inner margin of the second basipodite of pes IV a few lamellous setae like those of the adult females
were found in the young females, but in the males a few marginal hairs of usual structure were found.
The fifth pair of legs in the males is as seen in fig. 8a (Pl. II) rather slender.

Y? (St. IV). Size: A single female from Thor St. 165 1905 measured 2:06 mm.; anterior di-
vision 1°67; urosome 0739 mm. ‘The antennulae reached to base of furca; the shape of the body is in
the main like that of the adult females, but the abdomen has as usual only three somites. The
structure of the appendages was not examined in details.

Parasites. In several adult females of this species curiously twisted bodies (text-figs 22 h—j)
to the number of one or two were found, now on the right and now on the left side; they are by a
delicate stalk fastened to the skin of the body wall between the insertion of the maxillae and maxil-
lulae; their content is finely granular. About their nature I do not at present wish to express
any opinion. They were found in the following number of adult females from 5 stations viz. 1 from
Ingolf St. 20, 25 from Thor St. 152 "9/6 1904, 20 from Thor 2"/5 St. 153 and 4 from %/, 1904 St. 78.
At St. 152 and 1 53 they was generally found together with the “parasites” to be described.

In a great number of adult females of this as well as of the following species elongate obovate
bodies (text-figs 22 e—f) were observed; they are by a stalk and a terminal disc fastened to the chitin
of the maxillulae (in a specimen from Ingolf St. 19 f. inst. to a seta of Le), but especially of the max-
illae. These structures are of somewhat different shape in the various animals, with the tip more or
less pointed; they consist of a transversely striated wall, which, in contrast to the stalk, is dissolved
into a solution of potash and a content with vacuoles but without distinct nuclei in glycerin prepara-
tions. The stalk is hollow and widened out towards the sac, which is here more or less pointed.

These structures were sometimes. found on the left sometimes on the right side to the number
of one to four; they were found in the following number of specimens in one sample from Ingolf, and
in 11 from Thor: viz: Ingolf St. 19 2 specimens; Thor St. 152 (!9/6 1904) 25 specimens, St. 153 (?°/6
1904) 20, St. 154 (?"/s 1904) 3, St. 78 (*/, 1904) 8, St. 285 ("/g 1904) 5, St. 214 (?#/, 1904) 1, St. 183
(#4/, 1904) 6, St. 104 (24/; 1904) 10, St. 164 (29/s 1905) 1 and St. 72 (8/6 1905) 3 specimens. It is rather
curious to notice that the distribution of these “parasites”, which in some features are not unlike
spermatophors, is very irregular within the area; they were most common in Denmark Strait, and
"very searce at the southern stations. At the station (Thor 9/; 1904 St. 70) at which the greatest num-
ber of specimens of G. temuispiuus viz 890 £2 were collected, these structures were not observed.

Occurrence. The Ingolf Exp. has gathered this species at the following stations in
Davis Strait.

25/6 1895. St. 24. 63°06 L. N. 56°00 L. W. V.! 200—0 fathoms. Temp. at surface 42°C. 1 f9.

26/6 1895. St. 25. 63°30 L. N. 54°25 L. W. V." 200 —o fathoms. — ag Gut £9:

1/, 1895. St. 27. 64°54 L. N. 55°10 L. W. V.* 200—o0 fathoms. — 3:97 Ger a9.

_In the Atlantic south-east of Greenland it has been taken at 2 stations.
20/6 1895. St. 20. 58°20 L. N. 40°48 L. W. V.t 200—o fathoms. Temp, at surface 61°C. 2 f9.
18/5 1895. St. 19. 60°29 L. N. 34°14 L. W. V.t 300—0 fathoms. = 92x: Cegi ty
1 y$ (V); ryd (V).

ee ee ee Oe eee

eS

COPEPODA 93

In Denmark Strait it has been taken.
21/, 1895. St. 11. 64°34 L. N. 31°12 L. W. V.! 200—o fathoms. Temp. at surface 82°C. 1 f9.

The S/S. Thor has in Denmark Strait at four stations from 1904 taken numerous specimens,

of which numerous were infected with “parasites” of both kinds.

19/6 1904. St. 152. 65°00 L. N. 28°10 L. W. Yt. 800 M. Wire about 100 £9; 1 y2(V); r yo (V).

20/, 1904. St. 153. 65°20 L. N. 27°12'°5 L. W. Yt. 800 M. Wire 80 £9; 3 yP2(V); 2yd (V).
21/, 1904. St. 154. 65°27 L. N. 27°10 L. W. Yt. 800 M. Wire 85 £2; ry?2(V); ryd (V).
18/6 1904. St. 150. 65°50 L. N. 26°53 L. W. Yt. 4oo M. Wire £-£9.

In the Atlantic south of Iceland the S/S. Thor has taken numerous specimens from deeper

layers; comparatively few specimens were infected with the said parasites.

Thor *°/, 1904. St. 78. 63°08 L. N. 21°30 L. W. Yt. 750 M. Wire _ 50 f9.
10/, 1904. St. 180. 61°34 L. N. 19°03 L. W. Yt. 400 M. Wire 26 £9.
/, 1904. St. 285. 62°49 L. N. 18°40 L. W. Yt. 500 M. Wire 125 £2; 3ych (V).
t/, 1904. St. 183.61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire about 100 f?; 14 f6'; 4 y?(V);
7ySh (V).
?4/, 1904. St. 104. 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 35 £2; 2 yc (V).

In the Iceland-Feroe channel the S/S. Thor has taken the species at four stations a single

time in big numbers, only few specimens bore “parasites”.

Thor 29/g 1905. St. 164. 61°20 L. N. 11°00 L. W. Yt. 300 M. Wire 1 f9.
22/, t904. St. 99. 61°15 L. N. 9°35 L. W. Yt. 1700 M. Wire 2 f9.
9/, 1904. St. 70. 63°35 1L.N. 6°20 L. W. Yt. 100 M. Wire 890 f9; 4 y?(V); 7 yc (V).
27/, 1904. St. 124. 61°04 L. N. 4°33 L. W. Yt. 100 M. Wire 28 f9.

Outside the Ingolf area the S/S. Thor has taken the species at the following stations.

Thor 15/6 1905. St. 82. 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 2 f9.
8/6 1905. St. 72. 57°52 L.N. 9°53 L. W. Yt. 1500 M. Wire 23 £9; 1 y?(V); 1 yo (V).
3t/g 1905. St. 167.57°46 L. N. 9°55 L. W. Yt. 1500 M. Wire 8 £9; 1 y?(V); 3 yeh (V);

I y? (IV).
North of Iceland the species was taken by S/S. Thor at a single station.

22/, 1904. St. 214. 67°19 L. N. 17°55 L. W. Yt. 800 M. Wire 60f92; 2£4; 1 y2(V); 3 yo (V).

Distribution. The species has previously been recorded fairly common in the eastern part of
the north polar basin crossed by Nansen; specimens were found as far north as 85 Lat. N., and
here near the surface; at the other stations they were found at considerable depth. From Spitsbergen
it has been recorded by Mrazek. In the ocean lying between Spitzbergen and Greenland it was
found fairly common from altogether 18 stations, scattered all over the area crossed by the Duc d’Or-
léans as far north as 80° Ll. N. 2°47 L. E.; its range was between 100 and 700 meters in depth. In the

Norwegian Sea it was found a few times between Finmarken and Jan Mayen between 500 and 1000

94 COPEPODA

meters. From the west coast of Greenland it has been recorded from “Lille Karajakfjord” by Van-
héffen. It is, as seen from the above, fairly common in the Iceland-Feroe channel between 100o—o
meters, and so it is in the Feeroe-Shetland channel; its shallowest record here is according to Farran
(I9II Pp. 97) “from a haul of roo—o meter in 143 meters of water from a station lying to the east of
Shetland”. It has as far south as 55° L. N. “several times been met with in small numbers in the
deep water of the Atlantic slope off the south west coast of Ireland at depths of from 500 to 600
fathoms”. The species has not been taken by the Monaco; the records from the Gauss and the Siboga
Expeditions seem to be very doubtful, and shall presently be discussed.

The Ingolf and the Thor’s records of this species from Baffin Bay, Danmark Strait, the sea
north of Iceland and the Atlantic south of Iceland as far south as 60 to 51° L. N. complete the picture
of this species as a North Atlantic and arctic species from the intermedial layers.

Remarks. That the described species is identical with Sars’ G. tenuispinus does not seem
doubtful, in spite of the slightly bifurcate rostrum and the stiff broad bristles on the inner margin of
the second basal segment of the fourth pair of legs, which were not mentioned by the author; the
latter character was well described by Wolfenden for his species G. borealis; Wolfenden has later
on identified his species with G. ¢enuispinus, but has in the list of species, probably by a slip of the
pen, given it the name G. pungens Giesbr.

Wolfenden has identified specimens from Cap and the Antarctic ocean with the northern form;
he has examined specimens from the northern as well as the southern regions without being able to
find great differences; he may be right; but as the differences between the species are often so small,
and as too few characters are generally used by the authors, I prefer to look forward to further in-
vestigations, not the least on account of the different localities. It is on that account that I have
given so full a description of this species.

A Scott is certainly right in regarding his father’s species Huchete Hessit var. similis (1894
pp. 58—59 Pl. VI figs 24—25) as being related to Gazdius; but as its size is only 2°2 mm., as the terminal
segment of the left pes V is somewhat swollen at the base and as it “wants the prominent rostrum
of Luc. Hesset” (his figure does not show any rostrum), I do not think his identification ought to be
accepted. A. Scott identifies his G. similis Th. Scott with G. pumgens Gbt.; in this he may possibly
be right. He writes (p. 52). “I regard the form described by Sars as Gaidius tenuispinus ... to be
identical with this species”, His figures of the pes V and of the rostrum of the male, which are

somewhat insufficient, do not support his view.

24. Gaidius brevispinus? G. O. Sars.
(Pl. II figs. 7a—h; pl. III figs. 1 a—j; textfigs 24 a—i).

1900? Chiridius brevispinus n. sp. G. O, Sars, p.68, pl. XIX. | 1905? Gaidius brevispinus G. O, Sars. G. O. Sars, p. 3.
1902? Gaidius — G. O. Sars. Mrazek, p. 521. 1905? — affinis n. sp. G. O, Sars, p. 9.
1903? — _ — G. O, Sars, pp. 162— | 1905. — brevispinus G. O, Sars. Farran, p. 33.
163; suppl. pl. VI. 1906. — _ —_ Pearson, p. 13.
1903 ? = oF a Norman, p. 136. 1908. _ _ _ vy. Bremen, p. 35.
1904. — major n. sp. Wolfenden, pp. 114—115; pl. IX | 1908. — affinis — Farran, p. 32.
; figs 7--8.

COPEPODA 95

Description. {£9. Size of specimen from Thor St. 183 4:05 mm.; anterior division 313 mm.,
urosome o'92 mm. Sars’ specimens measured 4°8mm., Wolfenden’s specimens 4°65 mm. and Far-
ran’s specimens measured 3:9—4'5.

The shape of the body is practically as figured by Sars, except for the distinctly longer lateral
spines of the thorax, which are directed downwards and backwards. The rostrum is not undivided
as stated by Sars, but is, as shown in fig. 7a (Pl. II), distinctly bifurcate terminally. On each side of
the vulva a somewhat triangular plate was found, and a short receptaculum seminis was observed
(fig. 7b); the structure of the genital apparatus was rather complicated, but was not examined in the
- details; figs 7 b—c will give an impres-
sion of its structure. The furcal rami “
are 14 as long as wide, and a little
shorter than the anal somite.

The antennulae do not reach
to the end of the anal somite, but only
somewhat beyond the end of the geni-
tal somite. The segment 2 is I'l as
long as 8~9, which is scarcely 11 as
long as segment 13, and 1'2 shorter
than segment 20; segment Ig is a little
longer than 20 and 22 which are of
almost equal length, and longer than
segment 2. The appendages differ from
those of G. tenuwispinus by the presence
of a Sp. in segment 13.

The antennae have the Re
about 1’5 as long as Ri, but are scarcely

Text-fig. 24. Gaidius brevispinus G. O. Sars.

different in other respects. The maxi/- a. £9. Head from the left with parasite attached to maxilla x 18. b. f9.
Pes I sin. in ant. view X 80. c., Pes II sin. Ri in ant. view X 80. d. fo.
Rostrum X 57. e. fo. Abdomen X 33. f£. fo. xX 9. g. YQ. (Stage V) X 33.
by Li 3; which only bears 4 setae in h. YQ. Abdomen lateral view X 33+ i, yo. Pes II Ri in ant. view X 80.

lulae differ from those of G. tenuispinus

addition to the sensory lobe, and by the Re III, which possesses 6Sa-+1Sp. The maxillae (fig. 7 d)
have the exterior margin less strongly convex than the preceding species; the Sp. 2 of the first lobe is
three times as long as the lobe itself, and the Sp. of lobe IV is stronger as well as longer than the
corresponding Sp of lobe V. The maxzllipes differs from those of the preceding species by a rounded
lamelli-form protuberance on the exterior surface of the second basipodite (fig. ta). The articulation
between the Re I—II of the first pair of legs is better developed than in G. tenuzspinus (text-fig. 24 b),
and so is the articulation between Ri I—II of the second pair of legs (text-fig. 24), the St. of pes II
has only 19 teeth; along the inner margin of the second basipodite of the fourth pair of legs distally
and posteriorly one to two rows of broad stiff bristles were observed (fig. 1c).

The oral surface of the /adrum has a well developed longitudinal series of hairs, which
are, however, only indistinctly divided into the usual 5 groups as seen in fig. 7f; group III is

96 COPEPODA

fairly well marked, and group IV has in addition to the inner series a lateral one with 10 short
hairs. The transverse series around the fourth pair of central spots is less prominent than in the
preceding species. The lateral group of hairs is assymmetrical in one of the examined specimens. The
granular damina labialis with the area in front of it is shown in fig. 7f Behind the lamina labialis
four partly fused groups of short spines are placed near the middle line. On the area labialis and the
lobi labiales altogether 5 longitudinal series of hairs (Pl. II fig. 7f S'—S5) arranged as shown in
figure were found.

fg. Size of specimen from St. 183 Thor 1904 was 3°34 mm.; anterior division 2°53 mm.; uro-
some 081 mm. Wolfenden’s specimen measured 311 mm.

The shape of the body is practically like that of preceding species, but for the shorter lateral
spines (text-figs 24d—f). The antennulae extend almost to the end of the abdomen; the segment 22
is 14 as long as the segment 17, but in other respects they are scarcely different from those of pre-
ceding species. The antennae are comparatively more clumsy, with comparatively shorter Re; the
manducatory part of the mandibulae is comparatively more thin-skinned (Pl. III fig. 1d), but in
other respects the mandibulae are scarcely different. The maxillulae (fig. 1) are fairly well devel-
oped; the Le I has as usual g setae; the Li I does not possess any setae, but a number of short
rounded sensory organs; the Li II which is quite rudimentary, and the Li III which has at least one
real setae, possess similar organs. The third basipodite has at least 2 setae and the Ri I—III 3 +
3 + 6 setae. The Re has as usual 11 setae. The maxillae are scarcely different from those of pre-
ceding species (cf. fig. 2h). The maxillipeds (fig. 1f) have the third basipodite 13 as long as the
basipodites I—II and 2.5 as long as Ri; the basipodites I—II have a rudimentary Li I and a fairly
well developed Li IV.

The first pair of legs has the articulation of Re I well developed (fig. 1 g), but not only Se
Re I but also Se Re II are completely wanting. The St. Re III of pes II has 37 teeth, and the inner
margin of the second basipodite in the fourth pair of legs is smooth and has, as seen by comparing
figs 7g and 7e another shape than in the female. The 7th fair of legs (Pl. III fig. rh) is very simi-
lar to that of G. éenudspinus, but the basal segments are comparatively shorter, especially the third one
of the right side. The left endopodite shows no trace of segmentation, and has no small terminal seta;

the left Re III has, as shown in fig. 1i, a rather characteristic structure. .

Y (Stage V). Size of female from St. 183 Thor 3:22 mm.; anterior division 2°53 mm.; uro-
some o69 mm.

The shape of the body, except for the structure of the abdomen, is scarcely different from that
of the adult female. The axtennulae extend distinctly to the end of the last abdominal somite; the Sp.
of segment 23 is only 1'5 as long as the segments 24—25. The mazxzllulae have only 10 setae in Re, the
exterior margin of the basipodite of the maxillae is less distinctly convex, and the laminous process
of the exterior surface of the second basipodite of the maxillpeds is less prominent, with a distal tooth.
The pes /7 has the articulation between the Ri I—II slightly developed (text-fig. 241i), and the mar-
ginal hairs of the second basipodite of the fourth pair of legs are in the male only fewer (about 10)
than in the pes III, but not different; in the female, however, not only the number is smaller (17 against

ig ll ah are es

COPEPODA 97

32), but the hairs are stiffer, and the row is distally turning around margin posteriorly. The fifth pair
of the legs (fig. 7h) is in several respects different from that of G. ¢enwispinus (fig. 8a).

Parasites? “Sacshaped” structures, like those of preceding species in a similar position were -
found in a single female from Thor St. 152 and in 29 females from Thor St. 183.

Occurrence. The Ingolf Expedition has not taken this species, but the S/S. Thor gathered it
at a few stations in Denmark Strait and south of Iceland viz:

19/6 1904. St. 152. 65°00 L. N. 28°10 L.W. Yt. 800 M. Wire 11 f9.

20/, 1904. St. 153. 65°20 L. N. 27°12°51L. W. Yt. 800 M. Wire 1 f9.

1/, 1904. St. 285. 62°49 L.N. 18°40 L.W. Yt. 500 M. Wire riot.

11/, 1904. St. 183. 61°30 L. N. 17°08 LW. Yt. 1800 M. Wire 160 £9; 3£¢; roy? (V); 42 yo (V).

24/. 1904. St. 104. 62°47 L. N. 15°03 L.W. Yt. 1500 M. Wire 2 f9.

Distribution etc. As the circumscription of this species is not quite sure, I feel obliged before

discussing its distribution, to write a few words about the synonymy.

The described species differs from Sars’ G. dbrevispfinus by the somewhat smaller size, by the
divided rostrum and by the much longer lateral spines; as Sars does not seem to have realised the
importance of the characters found in the laminous process of maxillipeds and in the curious setae of the
second basipodite of pes IV, the fact that he does not mention these characters is scarcely of impor-
tance. Wolfenden’s description of the female as well as of the male is very incomplete; the females
are bigger than my specimens, and the lateral corners seem to be like those of my specimens.
Farran has (1908 p. 32) examined specimens from the west coast of Ireland, which, as far as his few
remarks go, show exactly the same differences from Sars’ description as my specimens do; really I
do not doubt that they belong to the same species. Farran has, however, referred his specimens to
Sars’ G. affinis, and Sars has himself confirmed this identification, though his original specimens of
G. aoffinis only measured 36 mm. Sars’ description is too incomplete to be of much value. Though
Sars regards G. dbrevispinus as well as affinis from the Monaco Expedition as different species, it is
most probable that the animals which are recorded from the Feroe channel and the north-east
Atlantic under the name of G. major, affinis and brevispinus ought to be referred to the same species,
varying in size from 3°6 to 465mm. If this species is not identical with G. drevispinus its name ought
to be G. major Wolf. This species or variety is distributed as far north as Denmark Strait and
the Freroe-Iceland channel, and is found as far south at least as 50° L. N.; G. drevispinus proper
which, as seen above, differs from the southern form by the larger size and shorter lateral spines, has been
taken in the western part of the polar basin crossed by Nansen (at 84° L. N. rather plentifully), once
in the sea between Finmarken and Jan Mayen, but rather curiously not in any of the numerous
samples brought home by the Duc d’Orléans.

From G. intermedius Wolf. it differs by the less pointed lamina of the basipodite of the

maxillipeds.
25. Gaetanus Kruppi? Giesbr.
(Pl. III figs 3a—h; text-figs 25 a—o).
April 1903? Gaetanus Kruppi n. sp. Giesbrecht, p. 202, pl. | 1903? Gaetanus armiger Giesbr. J..C. Thompson, p. 17.

VII fig. 8, pl. VIII fig. 29. June 1903? — major u. sp. Wolfenden, p. 125.
The Ingolf-Expedition. III. 4. 13

98 COPEPODA
1903? Gaetanus armiger Giesbr. Norman, p. 137. 1908? Gaetanus Kruppi Giesbr. y. Bremen, p. 41, fig. 47.
1904? — major Wolf. Wolfenden, p. 114, pl. IX figs | 1908? — major Wolf. Wolfenden, p. 31.
7—8. 1908? -- Kruppi, Giesbr. Wolfenden, p. 32.

1905. = — — Farran, p. 33. 1909 9? _ — A. Scott, pp. 48—49, pl.
1905. _ Kruppi, Giesbr. G. O. Sars, p. 4. IX figs 9—15.
1906. _— major Wolf. Pearson, p. 14. -onew — — — A. Scott, pl. X figs 1—9.
1908. _- —- Farran, pp. 36—37. Igit? — major Wolf. Wolfenden, p. 231.
1908 ? — — — ov. Bremen, p. 40, fig. 45.

a c e

XIV

XI

VILI~IX

m °

Text-fig. 25. Gaetanus Kruppi Giesbr.
a. £9. Head & 33. b. £9. Abdomen xX 33. c. fd. Head X 33. d. Yo (st. II). Head XK 33. e. Y (st. IID).
Abdomen X 33. f. Abnormal spec. Head X 33. g. fo. Antennula sin. segments 800 9—17 X 33. h. Intestinal
tract X 9. i. Maxilla dext. in post. view 57. j. Maxillipes sin. in post. view 57. k. Maxillipes dext.
in anterior view X 57. 1. Yo (st. IV). Maxillipes sin. in anterior view 57. m. Yo (st. III). Mazxillipes
X 57. n-o. Yo (st. V—IV). Pes V anterior view.

Description. {9. Size: Specimen from Thor St. 104 measured 5.4 mm.; anterior division 4:2

mm., urosome 1'2 mm. Wolfenden’s specimens measured 5 mm.

The body, which appears moderately slender, is 2°7 as long as wide, and has a well developed

frontal spine (text-fig. 25 a), which is directed forwards and slightly downwards, and smoothly continued

into the dorsal outline of the body. The rostrum is short, and is terminally slightly bifurcate. The

COPEPODA 99

lateral spines of the fifth thoracic tergite (text-fig. 25b) are suddenly set off, slightly divergent and
reach the middle of the genital somite. The anterior division is 3:5 as long as the urosome, which
has the 4 somites and the furca of the following relative length viz. 46, 23, 19, 15 and 21; the furcal
rami are about 1:2 as long as wide. The genital area is similar to that of Gazdius (text-fig. 25 b).

The antennulae, which extend somewhat beyond the end of the abdomen, have the segments
24—25 almost completely fused and the appendages like those of Gatdius tenuispinus and Gaetanus
_ armiger; the Sp. segm. 23 is at least twice as long as segments 24—25. The segments 2, 8&9 and 20
are of about equal length and about 1-1 shorter than segment 19. The aztennae differ from those of
Gaetanus armiger (ci. Giesbrecht p. 221) by the Re II, which is distinctly twice as long as Re I,
and has not only the second but also the third Se placed on a conical protuberance. The mandibulae
differ from G. armiger by the fairly long plumous Sir of the third basipodite and the short Se 2 with
a few branches. The maxillulae and maxillae are scarcely differeut from those of G. armiger (text-fig.
251i). The third basipodite of the maxzllipes is 13 as long as the two first segments and 3 times as
long as the endopodite; the second basipodite has almost in the middle anteriorly on the exterior
surface a laminous process with a concavity turning forwards; its tip is somewhat produced and
rounded, and proximally to it a more or less distinct tooth is found (text-figs 25 k and j). The fourth Li
of the basp. II has in addition to the usual sensory lobe and two hairs a small conical process repre-
senting the third hair.

The pes I has the articular line between Re I and II distinct anteriorly, except near the inner
margin; posteriorly only a faint line was observed; the pes II has the St, which has 25 well separated -
teeth, distinctly longer than the Re III, in length almost equal to Re I—II. The basp. II of the
fourth pair of legs (fig. 3a) has about 25—30 stiff triangularly pointed marginal bristles, in the
main placed on the posterior surface. The number of secretory pores is completely like that of Gaz
dius, with a pore at the base of Se Re I in pes II.

The oral surface of the /adrum is in most respects like that of G. /atifrons (cf. fig. 5d); the
bristles in group 3—5 are more like spines; the transverse rows of hairs between the circular spots
of group IV, as seen in fig. 3 b, are more like Gatdius tenuispinus. The lateral outline of the labrum is
very much like that of G. drevispimus, with three small elevations; no setae were observed on the anterior
surface in front of marginal row. The lamina Jabialis (fig. 3c) is smooth and of another shape than
in G. latifrons, but in other respects, except for a somewhat different arrangement of the serrulae behind
the lamina, the labial appendages etc. are similar to those of G. latifrons.

As most specimens are very pellucid the intestinal tract, especially the black hindmost portion
is generally quite distinct. It shows a characteristic structure with a large somewhat pointed coecal sac
directed towards the frontal spine, a small dorsal one opposite the wide oesophagus, and behind the

latter a gentle concavity, in which the oviducts with big eggs are placed (text-fig. 25 h).

3. Size of specimen from Thor St. 183(?) was 5:04 mm.; anterior division 4 mm., urosome
ro4. Wolfenden’s specimen measured 4°65 mm.
The shape of the body is more slender; the anterior division is 3 times as long as wide

and almost 4 times as long as the urosome. The bifurcate rostrum is shorter and more clumsy
13*

100 COPEPODA

than in the female; dorsally to the frontal organ the outline is first bulked; above this a concavity,
and beneath the frontal spine another proeminence adorned with about ro transversely placed chitinous
lines, laterally somewhat convergent, are found. The comparative length of the first four abdominal
somites and the furea is 15, 34, 23, 23 and 14; the anal somite is, seen from above, almost completely
covered, and the furcal ramus is only a little longer than wide.

The antennulae (text-fig. 25 g) extend about to the end of the second abdominal somite, but
not as in the female beyond the end of the abdomen. The segmentation from segm. 8—r4 is difficult
to make out, partly because the articular membranes are rather indistinct and partly because a number
of faint transverse lines were seen between the real membranes; it seems, however, that only the segm.
12 and 13 are really fused; the segments 20 and 21 are completely, and 24—25 only partly fused. The
number of “Afstetasken” is like Giesbrecht’s description of Aetidius (Taf. 14 fig. 13), but the segments
8&9 possess 4. The segments 11—13 bear two setae each, of which the proximal is the longer, and is
inserted in a small protuberance; the Sd of segments 14, 15, 16 and 17 are placed on small protuberances.
The posterior seta of segm. 23 extends somewhat beyond the middle of segment 24. In the Re II of the
antennae no setae were observed. The mandibulae possess a large but soft manducatory part without
distinct teeth but with a short Sdi; the Basp. 2 has an ovoid minutely granular area, and the third one
as well as Ri I has no setae; the setae of the Ri and Re are better developed than in the female.
The maxillulae are in main features like those of G. brevispinus (fig. 1e) but the Basp. III seems
only to have a single delicate seta, and the Re only 10 setae. The maxillae and maxillipeds are scarcely
different from those of Gazdzus.

The pes I is more slender than in the female; the articular line between Re I—II is wanting
posteriorly; the Se Re II is represented by a very short delicate bristle; the glandular pore in the
outer margin of Re III, which is only indicated in the female, is well developed. The inner margin
of the second basipodite was found smooth not only in the fourth, but also in the third pair of legs.
The fifth pair of legs (Pl. III figs 3d—f) is in main features like that of Gazdius, but is as a whole
distinctly more slender. The right endopodite, which is half as long as Re I and distally and posteriorly
has a short tooth, is distally inflated and spoon-shaped; the Re II has the anterior process which
encloses the bowel-shaped cavity shorter and more prominent (fig. 3 f). The endopodite of the left legs
is almost ?/, of the length of the Re I; it is indistinctly divided into 3 segments, of which the second
is the shortest, and has no terminal seta. Inwards, at the base of Re III, a small process bearing 4
short hairs is found. ;

Y (Stage V). Size: female from Thor St. 183 (?) 400 mm.; anterior division 32; urosome o8 mm.
Farran’s young male measured 4°3 mm.

The relative length of the four abdominal somites and the furea is: 19, 21, 18, 19 and 17;
the furcal rami are 13 as long as wide. The anztennulae are distinctly longer than in the adult, and
the measurements are slightly different. The maxzllulae have, in contrast to the female, only 10 setae
in the Re, and the lob. IV of the second basipodite of the maxillipeds bears 3 setae as in the male, in
addition to the sensory lobe. The articulation between Re I and II in the first pair of legs is only
indicated anteriorly as a faint line; the St. of the Re III in the second pair of legs has only 20 teeth,

the setae along the inner margin of the basipodite of the fourth pair of legs are rather stiff. The

is bo
Re es eh, ee

COPEPODA 10;

male differs from the female by the presence of a fifth pair of legs which as shown in text-fig. 25 n,
is like that of Gaidius.

Y (St. IV). Size of male from Thor St. 165 was 3:29 mm.; anterior division 26; urosome
o69 min.

The body is comparatively slender, a distinct limitation between the head and the first thoracic
tergite is observed, the somites IV and V are as in other stages fused with well marked lateral spines.
The relative length of the abdominal somites and the furca is 11, 17, 19 and 13; the furcal rami
are 1'4 as long as wide. The antennulae extend about 3 segments beyond the end of the abdomen.
The mazxillulae differ as usual by the 9 setae of Re, but the Basp. III has only 3 Sa-+-1 Sp, and the
Ri I—II each 2 Sa-+-1 Sp; the laminous process of the maxillipeds has a slightly different shape with-
out terminal tooth (text-fig. 251). The pes I has Re II—III fused, but Se Re II is present; the fourth
_ pair of legs (fig. 3 g) has like the two preceding pairs, the Re II~ III fused, with 3 Se and 16 teeth
in the terminal seta; the secretory pore corresponding to the Se Re II is missing. The only difference
between the 2 sexes is found in the presence of a fifth pair of legs of the usual rudimentary type in

the male (text-fig. 25 0).

Y (St. III). Size of specimen Thor St. 167 2:48 mm.; anterior division 2:07 mm.; urosome o-41.

The shape of the body is distinctly more slender, and so is the frontal spine; the rostrum is
blunt; the head is as-in preceding stage well separated from the first thoracic somite, but also the
fourth from the fifth one, which has no lateral spines. The relative length between the two ab-
dominal somites and the furca, which is 14 as long as wide, is 12, 20 and 11. The antennulae extend
4 segments beyond the tip of the abdomen; the segments 2-3 and 4—5 seem to be fused, and the
measurements are in several respect rather different; it is curious that the segment 25, which is well
separated from the preceding one, is not only relatively but also absolutely longer than in any of the
preceding stages (it is shortest in the f9). The maxzllulae are like those of preceding stage, but differ
by 8 setae in the Re and by the Lil, in which one of the posterior setae is wanting (only 3 present),
and one of the anterior ones (S 5) is represented by a short spine. The other mouth appendages, except
the maxillipeds which have the the laminous process rounded, are in main features like those of
preceding stages (text-fig. m).

The pes I, which like pes III—IV have the Ri unsegmented, has a fairly distinct limitation
between Re I and Re II—III, and is in main features like fig. 3g; the pes III differs from II by less
distinct limitation between Re I and Re II ~III, but the latter segment has only 2 Se; the pes IV
is again more reduced, as seen in fig. 3h, as all the segments are completely fused, and as only a

single secretory pore was found.

Variation etc. A single specimen from Thor St. 152 showed a rather curious shape of the
dorsal outline behind the frontal spine; as the species was in all other respects like the rest, the
structure ought perhaps to be regarded as a kind of deformity (text-fig. 25 f).

“Sacshaped structures” like those described in G. ¢enwispinus are found in several specimens,
mostly adult females, but also in young ones of the penultimate stage; the following number of “para-

sites” were found in samples from the following 6 stations of Thor viz. 19/5 1904 St. 152 7 parasites in

102 COPEPODA

f2 and 1 in yd, ™/, 1904 St. 183 2 par. in f2 and yd, */, 1905 St. 167 13 in £9 and 2 in ¥§5 9/5 1905
St. 72 15 in £2, and 14 in ae 29/, 1905 St. 165 1 in £2 and 22/; 1904 St. 99 1 parasite in £9.
Occurrence. The Ingolf Exp. has not taken any specimens of this species, but it was gathered
in several hauls by the Thor.
In Denmark Strait:

19/6 1904 St. 152 65°00 L. N. 28°10 L. W. Yt. 1000 M. Wire 6 £9, 1 y? (V), 2y & (V).
800 M. Wire 7 f9?.

? 15 £9, 3 yP (V), 12 yd (V).

? 18 £2, 2£9(V), 10 yh (V), 2 yP (IV).
20/, 1904 St. 153 65°20 L. N. 27°12'°5 L. W. Yt. 800M. Wire 1 £9, 4y oh (V).
21/6 1904 St. 154 65°20 L. N. 27°10 LL. W. 2 £9, 2y? (V), 2yoh (V).

In the Atlantic south of Iceland it was gathered at the following stations.

to/, 1904 St. 180 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 1 £9, ry oh (V).
t1/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 39 f?, 23 fd. 10 y? (V), 31 yh (V), 4 yP {IV),
4y¢c (IV).
25/, 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 10 f?, 4fd, 15 y? (V), 9ych (V), ry? (IV),
1yo (IV).
East and south-east of Iceland it was gathered at 2 stations:
22/, 1904 St.gq 65°15 L. N. 9°53 L. W. Yt. 1700 M. Wire 3 £9, 1 y? (V), 1 y@ (IV).
12/, 1903 St. 164 62°10 L. N. 4°36 L. W. 1 £9.

South-west of the Faroes outside the Ingolf area the species was taken at the following stations:

15/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 2 yo (V); 2 y? (IV), 1 y (III).
800 M. Wire 1 y? (V).
8/6 1905 St. 72 57°52 L.N. 9°53 L. W. Yt. 1500 M. Wire 80f9, 5 fo, 36 y? (V), 83 yh (V), 7 y@ (IV),
16 yo (IV), 2 y (IID).
29/3 1905 St. 195 60°00 L. N. 10°35 L. W. Yt. 1500 M. Wire 5 £9, 1 yQ (V).
t/, 1905 St. 167 57°46 L. N. 9°55 L. W. Yt. 1500 M. Wire 46 £9, 12 y? (V), 13 yo (V), 5 yo (IV), 4 y (IID).

Distribution and Remarks. I have examined specimens of this species which were determined
G. Kruppi Giesbr. by Professor Sars. G. Krupfi Giesbr. differs from my specimens by the much
smaller size (?: 36—4 mm.; J: 3'7 mm.), and on that account I am not quite sure that they are iden-
tical. I have on that account at a earlier date preferred the name G. mayor Wolf, and this name is
printed on Plate III. But as the description of G. Kruffz was published a few months previous to
that of G. major (as stated by A. Scott), and as Wolfenden not only in his original description (1903
p. 114) says “the lamellar appendage of the posterior foot-jaw is absent”, but reiterates the same state-
ment as late as 1911 (p. 231), well aware of the importance of this character, I feel obliged to accept
the name G. Kruppi at present. As Wolfenden has identified drawings of specimens from the
west coast of Ireland which were submitted to him by Farran as belonging to G. mayor, and as
Farran (1908), about the species which he names G. mayor Wolf. writes “G. Kruppfi appears to be at

ee

ee es ee ee, eee ee

COPEPODA 103

most a rather smaller Mediterranean variety of this species”, it seems probable that Farran’s spec-
imens belong to the species described above. The female of which A. Scott in the Siboga Expe-
dition has given figures and has identified with G. Krupfi, is possibly identical with this species
(Size 5°77 mm.; lobe IV maxillipeds with 3 setae and frontal spine rather short), but the male is scarcely
so on account of the different shape of Re dextr. pes V. Scott regards Esterly’s G. brevicornis (1906
p. 56—57) as identical with G. Krupfz, though the lamella of the maxillipeds has quite another shape, and
his G. clarus (pp. 57—58) as the male of this species; in the latter supposition he is possibly right,
but it is in any case different from the male from the Atlantic.

If G. Kruppi and mayor of the different authors are identical, its distribution is wide (Indian
Ocean, South and North Atlantic and the Mediterranean); if only the localities which certainly belong
to the species described here are taken into consideration its range encompasses the North East
Atlantic as far south as 50° L. N. and as far north as 65° L. N.; it is distributed as far west as
Denmark Strait (L. W. 28°), and as far east as the Feroe-Iceland channel (L. W. 4°). All records show

that it is a deep sea species.

26. Gaetanus minor Farran.
(Pl, III fig. 4a).

1905. Gaetanus minor n. sp. Farran, p. 34, pl. V figs I—11. 1909. Gaetanus minor Farran. A. Scott, pp. 47—48, pl 1X
1906. _ — Farran. Pearson, p. 14. figs 1—8.
1908. _— _ — Farran, p. 37. ‘ IgII. _ — -- (minimus? n. sp.) Wolfenden,
1908, a= a — vy. Bremen, p. 41, fig. 46. Pp- 233— 234, text-figs 20a—e.

: 1908. — _ — Wolfenden, p. 32.

Description. f9. Size: 2:3 mm., anterior division 189; urosome 0-44 mm. Farran’s specimens
measured 2:4 mm.

The short rostrum is undivided. The anterior division is 4:3 as long as the urosome. The
lateral spines reach the end of the genital somite (fig. 4a). The genital somite is rather swollen below,
with a distinct receptaculum seminis. The caudal rami are almost as long as wide. The relative
length of the abdominal somites and the furca is 20, 9, 8, 8 and 7.

The antennulae reach just beyond the end of the genital somite; the measurements are prac-
tically as given by Farran, and the appendages are as in preceding species. The Re of the antennae
is scarcely 14 as long as Ri; the Ri I is twice as long as Re II, which is again 26 as long as Re I,
and 16 shorter than Re III. The Re II has the short Se 2 placed on a conical protuberance, but has
none for the more slender Se 3. The maxillulae differ from those of G. Krupfi by the 2 spinelike
Sp. of the Li 2. The third basipodite of the maxillipeds is 11 as long as the 2 first, and 2-7 as long
as the Ri; the second basipodite has, as stated by Wolfenden, a rounded lamellous process, and the
lobe IV has as usual 3 setae +a sensory lobe; the third basipodite has in a similar way as in G. miles
Giesbr. (cf. Taf. 14 fig. 24) the inner margin produced into a rounded process which slopes most
gradually towards the base, and here bears the usual row of teeth. This process is distinct but much
lower in G. Krupfi, and is only indicated in Gazdius.

The terminal seta in the exopodite of pes II, which has 14 well separated teeth, is rz as
long as the Re I—II. The second basipodite in the fourth pair of legs has 12 stiff pointed bristles

104 COPEPODA

of the usual structure. The secretory pore at the base of Se Re I is wanting in pes II, present in
I-IV.

Occurrence. The Thor has gathered a single adult female 7°/¢ 1904 St. 88 48°09 L.N. 8°30
L. W. Yt. 300 M. Wire. This species has been recorded from the west coast of Ireland from a depth
of about 400 fathoms, from the middle of the South Atiantic between 5° L. N. and 30° L. S. and from
the Malay Archipelagos.

Though Farran does not mention the process of the Re II of the antennae nor the lamellous
process of the maxillipeds, I do not doubt that the described species is identical with his G. minor; the
mentioned features are found in Wolfenden’s species, which he somewhat prematurely proposed to
name G. minimus, if it should turn out to be another species than G. minor; the only difference between
Wolfendens specimens and mine is the somewhat shorter antennulae, which do not extend beyond
the end of the genital somite, and the smaller size (1'775—2 mm.). Between my specimen and Scott’s
description of specimens from the Siboga Expedition no difference except the shorter antennules of
the females from the Siboga Expedition was found.

27. Gaetanus pileatus Farran.
(Pl. III fig. 6a; text-figs 26 a—e).

1903. Gaetanus pileatus n. sp, Farran, p.16, pl. XVII figs 1—11. | 1908. Gaetanus caudani Canu. y. Bremen, p. 42, fig. 48.

1904. _ caudani Canu. Wolfenden, p.114, pl. IX, figs | 1908. %— pileatus Farr. Farran, pp. 35—36.

20—22. 1909. a caudani Canu. A. Scott, pp. 46—47, pl. VIII
1905. — _ pileatus Farr, Farran, p. 33. figs 9—15.
1905. — caudani Canu. G. O. Sars, p. 4. IgII. a pileatus Farr. Wolfenden, pp. 229—231, taf. 27
1906. —_ -— — Pearson, p. 13. ; figs. 1—2, textf. 17 a—c.
1908? su -- — Wolfenden, p. 31.

Description. £9. Size: Specimen from St. 82 measured 5°74 mm.; anterior division (including
frontal spine o'4 mm.) 4°7; urosome 1:04 mm.

The frontal spine has, as seen in (text-fig. 26a) and as described by the authors, a very charac-
teristic shape; the frontal organ is rather indistinct; the rostrum, which is very short, is in some spec-
imens undivided, in others terminally slightly bifurcate.. The fourth and fifth thoracic somites show
dorsally trace of segmentation. The lateral spines are rather suddenly produced, slightly divergent,
and almost reach the end of the genital somite. The anterior division is distinctly 4 times as long as
the urosome, the genital somite is distinctly produced below, and the structure of the receptaculum
etc. is in lateral view like that of G. latifrons (cf. fig. 5 b).

The relative length of the abdominal somites and the caudal rami, which are almost as long
as wide, is 42, 23, 19, I9 and 20.

The antennulae extend 6—7 segments beyond the end of the abdomen. The measurements
provide some similarity to Gaetanus miles, but differ especially by the more slender distal segments;
the segment 19, which is the longest segment, is twice as long as segment 2, 1°7 as long as segments
89 and 12 as long as segment 22; the segment 19 is 2°3 as long as segment 24. In the antennae
the Re is only 11 as long as Ri, and the Ril is 25 as long as Re IJ, which only possesses a terminal

seta, and is only a trifle shorter than the Re VII. The maxillulae possess no spinules on the posterior

eee eet

a i ah OL A a i a

COPEPODA 105

surface of Li 1, but has about 14 fairly strong spitules on the anterior surface of Li III. The third
basipodite of the maxillipeds is 1:1 as long as the two first ones and 2°8 as long as the Ri; the exterior
margin of the second basipodite bears a fairly slender rounded lamella (text-fig. 26d) and the fourth
lobe is divided most distinctly by a deep cleft into a posterior ¢ b
smooth division and an anterior one, which possesses 3 setae
in addition to the sensory lobe.

The Re I—II of the first pair of legs are completely
fused with the exception of a small lateral incision. The ter-
minal seta of the second pair of legs has 19 teeth, aud is dis-
tinctly longer than the Re III, The second basipodite of the
fourth pair. of legs has 20 lamellous bristles. The secre-
tory pore of Re I is wanting in pes II, present in III—IV.

The labrum is anteriorly scarcely different from that
of the preceding species; orally it is as seen in fig.6a in main
features like G. Kruppi (PI. III fig. 2e); the longitudinal series has
in most groups two or more rows of hairs. ‘The transverse groups
of short hairs around the median circular spot Nr. 4 are on each
side dissolved into a somewhat triangular group as seen in fig.
6a, and somewhat behind it a transverse area of short spines
or granules is found.

The lamina labialis is like that of fig. 5e but is almost
smooth; in front of this we have the usual two lateral series
of slender spines, of which the more lateral is almost semi-
circular, while the median one is very short. In front, by a smooth
area separated from the lamina, a wide area covered with flat

granules and almost fused with the corresponding part of the’
other side is found. The 4 transverse groups of densely placed Text-fig. 26. Gaetanns pileatus Farr.

: ‘ - a . a. £9. Head X 18.

short spines behind the lamina are like those of G. Krupfi(fig.3¢). —, ¢0. Right caudal ramus in abnormal spec-
The lateral longitudinal series shows the following structure: imen X 57-

si ree : c. £9. Maxillipes sin in anterior view X 57.
Ser. Nr. 1 consists of 10 short hairs in a transverse group and 4. y< (Stage V) mvs. in ant. view X 57.

of 30 in a longitudinal group, continued upon the lobus labialis © ¥¢ Stage V) pes V in anterior view X 57:
and partly confluent with the series Nr. 2, which has 20 slender hairs placed longitudinally. The
series Nr. 3 has two groups behind, of which the more lateral is more posterior (in contrast to fig. 7f
Pl, II), and a longitudinal row which on the posterior surface of the lobus labialis is continued to
near the tip. The series Nr. 4 is posteriorly placed almost transversely, forming a convexity, turning
backwards and almost reaching corresponding part of opposite side, and is’ anteriorly continued to tip
of the lobus labialis. The series Nr. 5 consists of a median transverse group of about 30 longer and
shorter setae placed near the middle, and a more lateral partly longitudinal. group; this group is
not continued directly into any series on the labial lobe, but probably corresponds to the most medial

one which is dissolved into independent groups. Possibly the series 5 corresponds also to the longitu-
The Ingolf-Expedition. III. 4. 14

106 COPEPODA

dinal group. medially to the serrula 6-dentata and the inner series in front of the lamina (cf. Pl. II fig.
7£s 6); if this interpretation is right, the serrula 6-dentata (fig. 7{ s 7) perhaps corresponds to Ser. 4.
¥g (Stage V). Size of female from Thor St. 82 was 5°74, anterior division 4-2 mm., urosome 0°87.

The relative length of the abdominal somites and the furcal rami, which are about 12 as
long as wide, is 20, 23, :8, 20 and 17. The appendages show similar differences from those in the
adult as G. Krupfz; the lamina of the second basipodite of the maxillipeds is shorter and more rounded
(text-fig. 26d); but the inner margin of basip. II pes IV is smooth; the fifth pair of legs is in main
features like those of G. Krupfz (text-fig. 26 e). In contrast to Canu’s description of a ere male of
G. caudani the Re I—II of pes I are completely fused without Se Re I.

re (St. IV). Size of a male from Thor St. 82 was 3°72 mm., anterior division 3:01 mm., urosome
o'71 mm.; a female measured 3°5 mm.

The relative length of the abdominal somites and furca was 19, 18, 24 and 13. The anten-
nulae extend at least 8 segments beyond the end of the abdomen; the differences in the other appen-
dages are scarcely different from those déscribed in Gaetanus Kruppi.

Parasites and Abnormity. Sac-shaped parasites like those described in G. éenuispinus were found
in one specimen from Thor St. 78 and 99, in 5 from Thor St. 183, in 28 adult females from ‘Thor
St. 82 (Yt. 1200 M. W.) and in 60 from St. 72. In a single adult female the setae of the right caudal
ramus was branched (text-fig. 26 b).

Occurrence. The Ingolf Expedition has not gathered this species, but it has been captured at
the following stations by the S/S Thor in Denmark Strait.

19/6 1904 St. 152 65°00 L,. N. 28°10 L. W. Yt. 1000 M. W. ry? (V).

? 8 f9.
20/, 1904 St. 153 65°20 L. N. 27°12°5 L. W. 5 £9, ryd (V).
21/, 1904 St. 154 65°27 L. N. 27°10 L. W. : 1 £9, ryh (V).
In the Atlantic south of Iceland. |
12/, 1903 St. 164 62°10 L. N. 19°36 L. W. tyo& (IV).
tt/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 19 £9, 1 yo (V). .

24/; 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 34 £9, 1 yo (V).
2/, 1904 St. 286 61°49 L. N. 14°11 L. W. Yt. 800 M. Wire 3 £9, 1 y? (V).

In the Iceland-Feeroe channel.
12/, 1904 St. 78 61°7 L. N. 9°30 L. W. 3 f9.
; 22/, 1904 St. 99 61°15 L. N. 9°35 L. W.. 7 £9.
In the Atlantic, south-west of the Feeroes.

15/6 1905 St.82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 270f9, 38 y?(V), 15 yh (V), 3y? (IV), ry o (IV).
Yt. 800 M. Wire 4of9, 4y? (V), 3 yo (V).

8/6 1905 St.72 57°52 L. N. 9°53 L. W. Yt. 1500 M. Wire 180 £9, 23 y 2 (V), rydh (V), ry ch (IV).

2t/g 1905 St. 165 60°00 L,. N. 10°35 ly. W. Yt. 1500 M. Wire 1 £9, 1 yd (V).

20/6 1905 St.88 48°09 L. N. 8°30 lL. W. Yt. 300 M. Wire 2 f9.

COPEPODA 107

Distribution. About this species Farran writes (1908 p. 36) “this species is a very noticeable
feature in the deep-water fauna off the west coast of Ireland, occurring often in considerable numbers,
in almost every tow-net from 200 to 1150 fathoms”. i

The gatherings of the Thor seem to show that it is much more abundant south of 60° L.N.
even if it is found in Denmark Strait as far north as 65° L.N. By Wolfenden it has been
recorded from the South Atlantic, and it was found by the Monaco Expedition, as well as at 5 stations
from the deep water of the Malay Achipelago (5 females only).

Remarks. Though I have not seen Farran’s original description, I am quite sure that my
species is identical with his G. pi/eatus and different from Canu’s G. caudani (if this author has not
examined an abnormal specimen). As I have examined specimens determined by Sars as G. caudani,
no doubts exist ‘about its identification with the Monaco’s species; and the same is the case with
Wolfenden’s species, from the South Atlantic. As the lamina of the maxillipeds (Pl. VIII fig. 13)
was differently shaped in the Siboga specimens (length 57 mm.), I am not quite convinced of Scott’s
identification. Scott regards Esterly’s G. unicornis as identical with his G. caudant, which he
regards as the synonym of G. pileatus, but he is scarcely right, as the lamina of the maxillipeds
has quite another shape in Esterly’s species (1906 Pl. XII fig. 54).

28. Gaetanus miles Giesbrecht.
(Pl. III figs 7 a—b).

1888, Gaetanus miles n. sp. Giesbrecht, P- 335- 1905. Gaetanus miles Giesbr. G. O. Sars, p. 3.

1893. _- — Giesbr. Giesbrecht, p. 219, taf. 14 & 36. 1906, a ~ — «Pearson, p. 14.

1895. _ -- — Giesbrecht, p. 248. 1908. -- — .— _ Farran, p. 36.

1898. — a — ~ Giesbrecht & Schmeil, p. 32. 1908. _ — — y. Bremen, p. 39, fig. 42.

1903. _ — — Norman. p. 136, . 1909. oo _— — A,Scott, pp. 44—45, pl. VIII figs
1903. _ _— — J.C. Thomsen, p. 17. 1—8,

1904. _ _ — Cleve, p. ror. 1913. — — — Wolfenden,. p. 231:

Description. {9. Size of specimen from Thor St. 82 was 4:21 mm.; anterior division 34, urosome
oi mm. Giesbrecht’s specimen measured 35, Scott’s 43 and Wolfenden’s 3 mm.

The shape of the body is scarcely different from Giesbrecht’s figure; the anterior division
is 42 as long as the urosome, which has the relative length of the somites and furcal rami as
follows: 34, 13, II, 11, 15; the furcal rami are 13 as long as wide. The antennudae differ from those of
Giesbrecht’s specimen by the proportional length of the segments; the segment 1g is a little longer
than 22, which is the longest according to Giesbrecht, and this again is a little longer than
20; the segments 8~9, 13 and 2425 are ‘in G. miles of almost equal length, but in my specimens
segment 13 is rz as long as 8~ 9 and 12 as long as 2425. The mouth-appendages, with the excep-
tion of the maxzllipeds, are scarcely different from those of G. miles; in this pair of appendages the
third basipodite is 3 times as long as the endopodite, and 13 as long as the ‘Basp. I—II; the plate-
shaped process of the exterior surface of the second basipodite is rounded and almost semicircular
(fig. 7a), and distinctly different from Giesbrecht’s fig. 24. Taf 14. In the first pair of legs the
articular line between Re I — II was scarcely indicated; the Ri of the second pair of legs has the

articulation between Ri I—II fairly distinct anteriorly, and scarcely indicated posteriorly; the second basi-
14*

108 COPEPODA

podite of the fourth pair of legs possesses 15 strong knife-shaped spines (Pl. III fig. 7b). The glan-
dular pore at the base of Se Re I is wanting in the second pair of legs but found in pes IIJ—IV.

The oral surface of the /abrwm is in the. main like that of G. pdleatus (cf. fig. 6a Pl. II);
the first group in the longitudinal series consists of numerous short setae (2—3 setae deep), and
the second of somewhat longer ones; in the third group only a single row of fairly long spines
were observed, and in the third one a few very short ones were observed laterally in addition to the
inner row of long knife-shaped spines (cf. fig. 5d). The /amina Jabialis is smooth as in G. Kruppi,
but the area in front of and behind it is like that of G. datifrons.

Y@? (St. V). Size of female from St. 88 3:34 mm.; anterior division 2°76 mm., urosome 058,

The relative length of abdominal somites and furcal ramus, which is rz as long as wide, is
15; 13, 9, 12 and 11. The measurements of the antennulae are more like those of the G. miles, as
segment 22 is a little longer than 19, and as segments 8~9, 13 and 24~ 25 are of almost equal length.
In other respects of any importance the appendages are scarcely different from those of the adults,
except by the structure of the second basipodite in the fourth pair of legs, which is smooth and has
the inner margin almost straight, not suddenly produced as seen in fig. 7 b.

- Occurrence. The Ingolf Expedition has not taken this species, but the Thor has gathered a

few specimens at four stations viz.

/, 1904. St. 183. 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 f9.
to/, 1904. St. 180. 61°34 LN. 19°05 L. W. Yt. 400 M. Wire 1 f9.
15/6 1905. St. 82. 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 1 f9.
20/6 1905. St.88. 48°09 L.N. 8°30L.W. Yt. 300 M. Wire 1 y?.

Distribution. This species has previously been recorded from the west coast of Ireland, from
the area explored by the Monaco Expedition, from the South Atlantic between 20 and 4o L. S., from
the Malay Archipelagos and from the Pacific (3° L.S.—5° L. N. 99°—115° L. W.).

Remarks. I am not quite sure that the specimens which I have examined really are iden-
tical with Giesbrecht’s G. miles, which is smaller, has the relative measurements of the anten-
nulae somewhat different, the lamina of the second basipodite of the maxillipeds quite differently
shaped and only 5 instead of 15 spines marginally in the second basipodite of the fourth pair of legs.
Scott’s specimens agree with mine in the number of the mentioned spines, in the size and partly in
the shape of the lamina of the maxillipeds, but differ in the measurements of the antennulae. As
Scott’s specimens form a connecting link between Giesbrecht’s and the Atlantic specimens, I do

not think the establishment of a new species is warranted.

29. Gaetanus latifrons G. O. Sars.
(Pl. III figs 5a—g; text-figs 27 a—e).

1905. Gaetanus latifrons n. sp. G. O. Sars, p. 11. 1908. Gaetanus latifrons G. O. Sars. v. Bremen, p. 39, fig. 43-
1905. —_ holti n. sp. Farran, pp. 33—34, pl. VI figs | 1908. — holti Farran. Wolfenden, p. 31.

I—12, 1909. —- oS — A. Scott, pp. 49—50, pl. X figs
1905. — . longispinus n. sp. Wolfenden, pp. 7—8, pl. III. 10--17.

1906. _ latifrons G. O. Sars. Pearson, p. 14. I9llk _ — Wolfenden, pp. 232—233, fig. 19.
1908. _ — _ Farran, p. 36. 25

3

COPEPODA 109

Description. £9. Size of specimen from Thor St. 183 was 5‘1 mm.; anterior division 4 mm.;
urosome 1°11 mm. Sars’ specimens measured 4°85 mm., Farran’s specimens 51, Scott’s 54 and
Wolfenden’s 37—4 mm, —

The frontal spine, which has a triangular base, has as seen in fig. 5a the tip directed forwards
and upwards. The distance between the base of the frontal spine and the frontal organs, which are
placed on a small process, is almost straight with a low crest. The rostrum is terminally bifurcate.
The shape of the body is scarcely different from Farran’s figure; the anterior division is 2°5 as long
as wide and 36 as long as the urosome. The genital somite (fig. 5b), which is distinctly 14 as wide
as long and 11 as deep as long, has a fairly prominent receptaculum seminis. The relative length of
the abdominal somites and the furcal rami is the following: 42, 23, 19, 18 and 21; the furcal rami are
rr as long as wide.

The antennae, which have the Re about 13 as long as the Ri, have the RiI almost twice as
‘long as Re I, which is 17 as long as Re I, and a little shorter than Re VII. The ReI has a single

a e

terminal seta on a conical protuberance, and the Re II
has 3 setae, of which the basal is the longest and
like the median one is placed on small protuberances.
The maxillulae possess 5 setae on Li II; the Lil has
no spinules posteriorly and the Li III has none ante-
riorly. The third basipodite of the maxzllipeds is 3
times as long as the endopodite and 1°3 as long as
the first and second basipodites combined; the lamina
of the second basipodite (text-fig. 26 b), which is folded
in a characteristic way, is in the whole length faste-

ned to the anterior surface of the segment; the inner.
margin of the third basipodite is basally not straight

d c

as shown in Farran’s figure, but slightly convex as }
Text-fig. 27. Gaetanus latifrons G. O. Sars.

figured by Scott. a. £9. Maxilla sin in post. view < 57. b. £9. Maxillipes

Th cas a e sin, in ant. view X 57. c. Y (stage IIl). Maxilla dext. in
© first: p f legs /has a well developed ant. view X 57. d. Y (stage II). Maxillipes sin. in an-

articulation between Re I and II, and the Se of Rell terior view 57, © Yo (stage V). Pes V im anterior
almost reaches the end of Re II. The second pair of feu te

legs has a well developed articulation between Re I and II, and a glandular pore at the base of Se
Re I; the terminal seta, which has 23 teeth, is a little longer than the Re III, and of equal length
to Re I—II.

The second basipodite in the fourth pair of legs has about 25 knife-shaped spines as shown
in fig. 5c.

The oral surface of the /aérum is fairly characteristic, as shown in fig. 5 d, especially the trans-
verse rows of granules around the median circular spot Nr. 4; the /amina labial’s has a characteristic
granulation as seen in fig. 5e, which also illustrates the area in front of it. The arrangement of setae
in the lateral series behind the lamina labialis is not unlike that of G. pileatus: Ser. set. 1 consists
of about 70 short setae placed in a longitudinal group: The series 2 seems to be represented by 3

IIo COPEPODA

groups with from ro—25 slender ‘setae, of which the first is placed behind near the middle, while the
third, which is more longitudinal, is placed laterally more in front. The series Nr. 5, to which the two
most medial groups mentioned ought perhaps to be referred, falls in this species naturally into three
divisions, forming together an outwards convex figure (like that in fig. 7f Pl, II) consisting of 2 hairs
most medially, well separated from the group of 14 hairs, which is almost fused with the dense longi-
tudinal row almost reaching the end of the labial lobes; the series Nr. 3—4 are scarcely different from
those of G. brevispinus {Bt II fig. 7 f).

Ts (St. V). Size 7 female from Thor St 183 was 416 mm.; duterior division 3°29 ‘mm.;
urosome 0°87. | ;

There is indication of an articular line between head and first thoracic tergite, and between the
fourth and fifth ones. The relative length of the abdominal somites and the furcal rami, which are
12 as long as wide, is the following: 19, 19, 17, 19 and 17. The first abdominal somite is somewhat
produced below, more so than in the male. The inner margin of the second basipodite is in both sexes
almost straight, and distinctly different from that described in the adult female; in the female we find
about 20 stiff pointed setae, and in the male about g setae of usual structure (in pes II a close row of
20 is observed). The fifth pair of legs is very similar to that of G. Krupfi (text-fig. 27 e).

vs (St. IV). Size of female from Thor St. 183 was 3:13 mm.; anterior division 2°53 mm.;
urosome o’60. A male measured 3°45 mm.

The relative length of the abdominal somites and the furca is as follows 15, 18, rg and 13.
The antennulae extend by at least 2 segments beyond. the end of. the abdomen. The maxillulae
show differences corresponding to those described in G: Arupfi. The lamina of the maxillipeds
has a less complicated structure, is more prominent and of obtusely triangular shape. The Jes J has
the Re I—II fairly well separated, and has 3 Se pes I; the second basipodite of the fourth pair of
legs has only 3—4 setae along the inner margin. -The only difference between the male and female

is found in the presence of a fifth pair of legs (cf. text-fig. 27 0).

-Y (St. ll). Size. of specimen from St. 82 was 2°48; anterior division 2°04;.urosome 0-44 mim.
The head and tlie first thoracic somite as well as the fourth and fifth ones are well separated.
The frontal spine is scarcely different from that of the adult females, but the lateral corners of the
thorax are rounded without trace of spines. The relative length of the abdominal somites and the
furca is 15, 18 and 9. The antennulac, which extend 3 segments beyond the end of the ab-
domen, show similar differences from those of the adult ones as in G. Kruppi. The maxillulae have
only 8 setae in Le, but in other respects show similar differences as in preceding; the Li II possesses
5 setae as in the adult females. The exterior margin of the maxillae (text-fig. 27 c) is almost straight,
in contrast to the structure in the adult females, the structures in the two preceding stages forming
intermediary steps. The lamina of the maxillipeds is more regularly rounded and apparently more
prominent (text-fig. 27 d).
In the first pair of legs the segmentation of the exopodite is only indicated laterally; 3 Se are
present, but the two proximal ones are very short; the 3 last pair of legs are scarcely different from
those of G. Krupfpz. j i

COPEPODA III

Variations etc. In a single young female of stage V the third seta of the left caudal rami
was dichotomous. i

Sac-shaped “parasits” like those described in G. ¢emuisfinus were found in four adult females
and in a young male from St. 183.

Occurrence. The Ingolf Exp. has not taken this species, the S/S Thor has gathered it at the fol-
lowing stations. : ;

"9/6 1904 St. 152 65°00 L. N. 28°10 L. W. I y?(V).
™/, 1904 St. 183 61°30 L, N. 17°08 L. W. Yt. 1800 M. Wire 8 f9, 2 y? (V) 1 5yh (V).
*/; 1904 St.99 61°15 L. N. 9°36 L. W. 1 f9.

"5/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 1 y (IID).
"Jo 1905 St.72 57°52 LN. 9°53 L. W. Yt 1500 M. Wire rf9, sy?(V), 4yS(V) try? (IV), trys (IV).
3*/g 1905 St. 167 57°46 L,. N. 9°55 L. W. Yt. 1500 M. Wire 1 yo (V), ry? (IV).

Distribution. The species has been taken at several stations by the Monaco Expedition, and
is fairly common on the west coast of Ireland “at depths of from 330 to 1150 fathoms”. According to
Wolfenden it is “anschinen im Atlantischen Ocean sehr haufig, erscheint von dort auch in den
Fangen des “Gauss” und erstreckt sich nach Norden bis zur Westkiiste Grénlands”. A single spec-
imen has by been collected the Siboga Exp. in the Malay Archipelago.

Remarks. Between this species and Sars’ description of G. datifrons scarcely any difference
was found; in spite of some small differences, enumerated above, it is certainly identical with Farran’s
G. holtt, Wolfenden’s specimens were as a whole somewhat smaller, but in other respects scarcely
different. This species seems to differ from Scott’s description by the shorter antennulae and the
different shape of the lamina of the maxillipeds.

30. Gaetanus ferox n. sp.
(Text-figs 28 a—b).

Description. f¢. Size: 3:4 mm., anterior division 26'mm.; urosome 0-78 mm.

The shape of the body is most like that of Gatdius tenuispinus, but the head dorsally terminates
in a prominent, obtusely rounded keel (partly broken in the examined specimen). Below the frontal
spine the outline is almost straight, and is then convex towards the base of the clumsy rostrum, which
possesses two terminal points (text-fig. 28a). The head and the first somite as well as the two last
thoracic ones are completely fused; the lateral corners are regularly rounded, but somewhat in front:
of the margin are seen rather short slender spines, which probably only extend slightly beyond margin
(broken in examined specimen). The anterior division is 3°3 as long as the abdomen, which as usual
consists of 5 somites; the second somite is 15 as long as the third, which is a little longer than the first
and fourth; the fifth somite is just visible from above. The genital pore is found on the left side. The
furcal rami are almost as long as wide; the St. 2 is somewhat longer than the abdomen (text-fig. 24 b).

The antennulae extend distinctly beyond the end of the abdomen; the segments 20—2r are
completely fused, and the segment 22 has, at least on the left side, a characteristic structure, as it is:

widened out from the narrower middle portion towards the base as well as towards the tip.

112 COPEPODA

The measurements and appendages differ scarcely from those of G. Kruppi. The antennae are
like those of G. Krupfi, but the two branches are almost of same length. The mandibulae, maxillulae
and maxillae are scarcely different from those of G. Kruppi. The third segment of the maxiilipeds is
1'2 as long as the first and second combined, and 2-7 as long as the endopodite, but in other respects
this pair of appendages is scarcely different from those of G. Kruppz.

The first pair of legs is like that of Gatdius brevispinus (Pl. III fig. 1g), but the articular line
between Re I—II is indicated anteriorly, though wanting posteriorly; the Se of Re I and II are wanting.
The Se of RiI of the pes II is wanting; the St, which has about 30 teeth, is a little longer than Re
III, which is again a little longer than the Re I—II; no glandular pore is found at the base of Se
Re I, The pes III—IV have a secretory pore at the base of Se Re I; the basipodite of the third pair
has a marginal row of setae, but that of the fourth pair is completely smooth. The //¢h pair of legs
(text-fig. 28b) is in most features like that of Gaet. Kruppi (Pl. Ill fig. 3d); the right leg is
? less slender, especially the third basipodite, which
is, however, less clumsy than in G. drevispinus (PI.
III fig. 1h); the first segment of the right exopodite
has exteriorly a slight concavity almost in the
middle and, proximally to it, a slender seta (Se Re I),
thus indicating that this segment really corresponds
to Re IwII; the Re III differs from that of G.
- Kruppi by the structure of the terminal portion
(that distal to inner process) which is only two thirds

as long as the basal part and not in the least as long
eshte oR. \Guatieens foray ttn. as, and, proximally to a hair-shaped terminal part, has
a, Head from the left X c. 40. an inner lamina in the distal half. The right endopo-
a a ee ak dite when observed from behind, is almost completely
like that of G. Kruppi (fig. 3d), but viewed anteriorly it is seen to have a very characteristic form on
account of a wide deep “cavity”? and a terminal tooth not unlike a Prussian helmet, but with a prolon-
gation towards the base, as if to give protection to the back of the meck, The jes V sin has the Ri
of a similar shape as in G. Krugfz, but it is comparatively shorter, reaching only slightly beyond the
middle of Re I, and has the segmentation more indistinct; the first segment of the exopodite has the
outer margin somewhat convex, and is. terminally somewhat produced inwards; the Re III, which is.
scarcely rr as long as Re II, has a fairly long terminal spine, near the base of which a delicate

seta is. observed, as well as some hairy spots.

Remarks etc. Of this species I have only examined a single male, brought home by the S/S
Thor, and takem 8/5 1905 57°52 I. N. 9°53 L. W. Yt. 1500 M. Wire. —

. As except im the shape of the forehead it is in almost all characters like the male of G.
Kruppi, I think it is rightly referred to Gaetanus, It is certainly not the male of any of the species
of Gaetanus which has been mentioned in this paper; nothing indicates that it is the male of any
of the described species of Gaidius or Gaetanus, ~

COPEPODA 113

31. Euchirella rostrata Claus.
(Pl. IV figs 1a—h; text-figs 29 a—k);

1866. Undina rostrata n. sp. Claus, p. 11, taf. I fig. 2. 1905. Euchirella rostrata Claus. G. O. Sars, p. 4.

1883.? Euchzete hessii n. sp. Brady, p. 63, pl. XX figs 1—13. 1905. _ _ — Th. Scott, p.-223.

1892. Euchirella rostrata Claus. Giesbrecht, p. 232, taf. 15. 1905. _ -- — Esterly, pp. 152—153.
1898. = a —. Giesbrecht & Schmeil, p. 36. 1905. Nec. — — var.magna Wolfenden, p. 18.
1g00. ? =. - — Cleve, p.4, pl.2 figs 1—12. 1905. a _ — Farran, p. 36.

1902. ? _ _ — Wolfenden, p. 367. 1906. — — — Pearson, p. 15.

1903. Nec. — — — Thompson & Scott, p. 244. 1908. — _ — Farran, p. 38.

1903. — oa — Norman, p. 137. 1908 _ _ — v. Bremen, p. 47, fig. 52.
1903. — _ — J.C. Thompson, p. 18. IgII. —_— — — Wolfenden, p. 235.
1904. _ _ — Wolfenden, p. 129. IgI2. — _ — Esterly, p. 311.

Description. f£9?. Size: Specimen from Ingolf St. 19 measured 4:07 mm.; anterior division 3°26;
urosome o81 mm. The size of specimens from other stations varied from 3°25—42 mm. Giesbrecht’s

\ specimens measured 2°95—31 mm., Farrans 33—42 and Wolfendens from 2—3 mm.

Ri Re dext.

Text-fig. 29. Zuchirella rostrata Claus.
a. £9. Abdomen X 45. b. fo. Rostrum X 45. c. fo. Abdomen x 45. d. fo. Tips of pes V from the right x 150.

e. yo (St. V). Abdomen X 45. f. yo (St. V) Pes V X60. g. yo (St. IV) Pes V X60. h. £9. Body X 33.

i-j. Irs (St) xX ask. hd 1X, 33.

The long and pointed rostrum is more vertical and the head is much more suddenly raised
than seen in Giesbrecht’s fig. 23 (Taf. 36) (text-fig. 29h). The genital somite has the ventral pro-
tuberance more regularly raised, especially behind, than shown in Giesbrecht’s fig. 17 (text-fig. 29 a).

The antennulae differ from Giesbrecht’s description by the comparatively longer segment
2, which is almost as long as segments 8% 9. The maxillulae differ from Giesbrecht’s description
(fig. 28) by one instead of 2 delicate Sa in Li 2, and by the presence of a posterior process bearing two
rudimentary setae(?) on the Li 3 in addition to the two well developed Sa. The sensory conical process
of Lob. IV of the second basipodite of the maxillipeds is rather small.

The Jes 7 is completely like Giesbrech’s fig. 11 (Taf. 15); the Re III has a minute pore in
the outer margin, somewhat posteriorly, and nearer the base than the tip. The es 77, which has 22 teeth
in the terminal setae, has the systems of glands of the Re well developed, in a similar way as figured

The Ingolf-Expedition. ITI. 4. 15

114 COPEPODA

by Giesbrecht (fig. 27); the pores are placed on small rounded elevations somewhat removed from the
margin; the Re I has no pore, the Re II has one near the base of Se and the Re III has 2, placed at
the base of Se I and Se III; the Ri III possesses a minute pore near tip on the anterior surface.

The ges /7J—IV have, in addition to the mentioned pore, one near the base of Se ReI; the
pes IV is like Giesbrecht’s fig. 27, except for the somewhat different shape of the glands and the
different number and arrangement of the spines on the inner margin of the second basipodite. In one
specimen (Pl. 4 fig. 1a) 7 triangular lamellae were observed, decreasing in size distally and posteriorly;
the seventh is placed on the hinder surface; in addition to these, 3 quite rudimentary teeth were found;
in no specimen was the number of spines greater, in several it was smaller, and sometimes almost com-
pletely like Giesbrecht’s fig.; the arrangement is not always symmetrical.

The area behind the rostrum is almost straight; separated from this by a transverse groove
the /aérum proper, which consists of a convex anterior portion by a shallow groove, separated from
the projecting free hinder margin adorned with two series of bristles; no bristles were observed in
front of the free margin.

The oral surface (Pl. IV fig. 1b) shows a very characteristic structure. In front of the first central
circular spot is a transverse row of minute granules; behind the spot I a transversely placed group of
spinules is found, probably formed by the fused /irs¢ groups of the longitudinal series. The second group
is,as shown in figure, assymmetrical, and seems partly to be fused with the lateral group; it consists of a
number of acicules and bristles. The ¢hzrd group consists of about ten fairly long setae, and is fairly
well separated from the following group, the fourth one, with 15 comparatively short setae. This group
is almost completely fused with the //¢/ one; laterally to these two groups a longitudinal series of about
20 setae is found. Behind the central spot Nr. 3 a rather irregular transverse group of spinules is observed,
and behind the spot Nr. 4 a transverse row of more delicate spinules is found. ©

The /amina labialis is granular, and has a concave posterior margin (fig. 1c); the area in front as
well as that behind the lamina has as seen in figure a fairly interesting structure. The lateral series
of setae behind and upon the labial lobes show as seen in fig. 1d an arrangement which is distinctly
different from that of Gaidius, as the two first series and partly the third are represented by four
areas of spinules.

&. Size of specimen from Ingolf St. 47 was 2°99 mm.; anterior division 2:18 mm.; urosome o'8r
mm. Cleve’s specimen measured 2°58 mm.

The body is comparatively longer and more slender than in the female; no frontal keel is found,
and the rostrum is fairly long and slender (text-fig. 29b); no trace of limitation between head and first
thoracic somite was found. The anterior division is 2°6 as long as the abdomen. The first abdominal
somite, which has the genital opening as a vertical split on the left side, is about as long as the second
one; this is a little longer than the third, which is again a little longer than the fourth; the striated
seam along the hinder margin of somites II—IV is only indicated dorsally (text-fig. 29c). The anxtennulae
extend about to the middle of the abdomen; the segment io is separated by a rather indistinct line
from 8—g; the limitation between segments 1213 is indistinal posteriorly. The segments 20—21 are
well separated on both sides. The measurements are very similar to those of the female, but the segments
beyond 18 are comparatively shorter. The differences in the appendages are as in E. messinensis. The

COPEPODA 115

antennae have the endopodite at least as long as the exopodite, and it extends beyond the Re VI; the
setae are better developed; the Re II has in the middle inwards a rudimentary tooth (for a Si). The
mandtbulae have as seen in fig. re a fairly well developed but soft-skinned manducatory part with a few
rudimentary teeth. The maxzllulae (fig. 1h) have 7 plumous setae, of which the 2 proximal are some-
what shorter in Le 1; the Li 1, which is fairly well developed but soft-skinned, possesses a number of
soft setae, of which some, though more or less swollen at the base, have not yet lost ther original
shape, while others are represented by short eminences; the Li2 seems to be represented by a short,
somewhat ringed eminence without setae; the Li 3 (?) has a single setae; the basipod 3 -+ the Ri pos-
sess 4 plumous setae. The Re has 11 setae. The maxiliae form a ringed, elongate, soft-skinned organ,
which bears slender setae along its inner concave margin. The ma-xzllifes is longer and more slender
than in the female; the second basipodite has setae only on the Lobe IV, namely a strong plumous one
and a shorter one in addition to a sensory lobe. The fes / differs from that of the female by the almost
straight margin (fig. 1f); the St. of Re III of pes J7 has 37 teeth. The inner margin of the second
basipodite in the fourth pair of legs is only sligthly convex, without setae or teeth.

The pes V (text-fig. 29d) provides great similarity to that of Gaefanus, but is nevertheless
distinctly different (Pl. 1V fig. 1g). The Ri dext. is long and somewhat enlarged towards the end, where,
inside, it bears two short delicate setae. The Re I~II (?) of the right leg is fairly long and slender. The
Re III (?) is somewhat enlarged inwards, and then rather suddenly attenuated; exteriorly, at the base
of the terminal part, which distally has an inner membrane and has the pointed tip curved
outwards, a slender Se is placed; the distal part is at least 1'5 as long as the proximal. The Ri sin.
is fairly long and slender; the Re III of left leg, at the base of which a tuft of hair is found, is short,
almost fused with preceding segment and produced into a hairy spine-shaped protuberance.

The structure of the oral surroundings is in the main like that of the female (cf. fig. re); the
labrum proper, which partly overlaps the chitinous bed in which the manducatory part of the man-
dibulae is placed, is well developed, but appears, but for a terminal tooth, to be smooth outside as well
as inside. The dadzal lobes, which consist of soft ringed chitin, are just indicated, and do not possess
any hairs. The lamina labialis etc. are completely wanting. This structure corresponds well with the
rudimentary state of the masticatory part of the maxillulae, not being adopted for predatory purposes,
nor even for taking any nourishment at all.

¥g (St. V). Size of female from Ingolf St. 47: 3:06 mm.; anterior division 2°44; urosome 062
mm. A young male measured 2:14.

The limitation between the head and first thoracic somite is generally better marked than in
the adult female (text-figs 29i—j). The first one of the four abdominal somites is ventrally produced
in the female, barely so in the male (text-fig. age). The appendages show the usual differences from
those of the adult females; the St. of Re III pes II has 14 teeth; an interesting difference is found
in the wanting glandular pore at the base of Se I Re III; the second basipodite of the fourth pair of
legs is smooth, while 7 short hairs are found in the females, corresponding to the spines of the adult
females. The 7i/th pair of legs is as seen in text-fig. 2gf rather clumsy and quite unlike Cleve’s
fig. 3 Pl. II; the Re dext., which is longer than the Ri dext., and which has a strong terminal spine,

is distinctly longer than the Re sin.
15*

116 COPEPODA

¥g (St. IV). Size of female from Ingolf St. 47 is 224 mm.; anterior division 1°85; urosome
o39 mm. A male from the same station measured 21 mm.

The appendages show similar differences as in G. Krupfi, f. inst. glandular pores are only found
at the base of Se Re II and Se 3 Re III; the St. of pes II has only 13 teeth; the inner margin of the
basipodite of the fourth pair of legs appears smooth. The only difference between the male and female
is found in the presence of a fifth pair of legs in the former (text-fig. 29g).

Y (St. III). Size of specimen from Ingolf St. 47 was 165 mm.; anterior division 1°3 mm.; uro-
some 0°35 mim.

The thoracic somites IV—V are well separated; the antennulae extend scarcely to the end of
the abdomen. The appendages show differences corresponding to those in G. Krupfi.

Abnormality. In a single adult female the right furcal branch had the third and the second terminal
setae dichotomously branched. There is a well marked difference between pellucid and less transparent
specimens with more prominent eggs. In most specimens the intestinal tract consists of a wide
stomach which, in front of the insertion of the narrow oesophagus, is continued into a wide coecal sac
and behind is turned upwards to meet the following portion, and the intestine proper. In a single
specimen the connection between the stomach and the intestine was twisted, and not lying on the
same level.

Occurrence. The Ingolf Exp. has on the west coast of Greenland collected a young male
(stage IV) 6/6 95 St. 25 63°30 L. N.. 54°25 L. W. V 200—o fm. Temp. 2°9° C. The Ingolf Expedition has
not collected this species in Denmark Strait, but the Thor has taken it at the following stations:

Thor 19/6 1904 St. 152 65°00 L. N. 28°10 +=. W. Yt. 1000 M. Wire 1 £9, 1 y(V), Yt. 100 M. Wire 1 fQ,
Yt. ? 3 £2, 3y? (V), 3yd (V).
20/6 1904 St. 153 65°20 L. N. 27°12°05 L. W. Yt. 800 M. Wire 1 y? (V).
20/5 1904 St. 154 65°27 L. N. 27°10 L.W. Yt. 80 M.Wire 1 f9, 2 y? (V).
18/6 1904 St. 150 65°50 L. N. 26°53 LW. Yt. 400 M. Wire 1 y?.

In the Atlantic south-west and south of Iceland the Ingolf Expedition has gathered the species

at the following stations:

8/6 1895 St. 19 60°29 L. N. 34°14 L. W. V* 300—ofm. Temp.9° C. 48 £9, 8 y? (V), 4yc (V).

7/6 1895 St.18 61°44 L. N. 30°29 L.W. V! 200—ofm. — 10° C. 13 f9?.

16/6 1895 St. 17 62°54 L. N. 26°34 L.W. V! 200—ofm. — og1°C. 2f9, ry? (IV).

3/6 1896 St. 68 62°06 L. N. 22°30 L.W. V! 1oo—ofm. — 88°C. 1f9.

9/3 1895 St. 40 62°03 L. N. 21°36 L.W. V' 1oo—-ofm. — 135°C. 9 f2.

‘/5 1896 St. 63 62°40 L. N. 19°05 L.W. V! 100o—ofm. — 83°C. 6 £9, 2y? (V).

19/, 1896 St.55 63°33 L.N. 15°02 L.W. V! 1oo—ofm. — 84°C. ry (V).

12/, 1896 St. 47 61°32 L. N. 13°40 L. W. V' 10oo—ofm. — 106°C. 2f9, 17 y? (V), 4£d, 10yh (V),

ty? (IV), ryd (IV), ry (III).

S/S Thor has south of Iceland gathered the species at 14 stations, but at 9 of these only a
few adult females were found.

COPEPODA 117

Thor '/, 1904 St. 285 62°49 L. N. 18°46 L.W. Yt. r00 M.Wire 148 f9?, 1 y? (V), 1 yo (V).
2/ 1904 St. 285 62°49 L. N. 18°46 L.W. Yt. 800 M. Wire 31 f9.
t/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 750 f9, 3 yo (V).
25/; 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 2 yo (V).

In the Iceland—Feroe channel the Ingolf Expedition has taken the species at 3 stations, and

the S/S Thor at 5 stations.

20/, 1896 St.57 63°37 L.N. 13°02 L. W. V! 100o—o fm. Temp. 82°C. ry (V).
20/, 1896 St.59 65°00 L. N. 11°16 L. W. Apstein 12 1145p.m. — 15°C. ry (IV).
t/; 1896 St. 45 61°31°5 L.N. 9°43 L.W. V* 100—0 fm. OT CH PY Ss (V):

Thor 2°/s 1905 St. 163 62°36 L. N. 12°05 L.W. Yt. 300 M. Wire 3 f9.
22/, 1904 St. 100 61°21 L. N. 10°39 L.W. Yt. 180 M. Wire 1 f9, 3 yo (V).
29/5 1905 St. 164 61°20 L. N. 11°00 L. W. Yt. 300 M. Wire 35 f9.
29/s 1905 St. 165 60°00 L. N. 10°35 L.W. Yt. 100 M. Wire 1 f9?.
23/, 1905 St. 124 61°04 L. N. 4°35 L.W.. Yt. 1000 M. Wire 1 f9.

The Danish East-Greenland Expedition has, '8/, 1900 Io p. m. F. 346 at the surface near Kap Dan
(Tarsuak Fjord), taken a single adult female.

Lundbeck has "/; 1890 55°25 L. N. 29°5 L. W. gathered 1 f?, 1 y? (IV).

The S/S Thor has, outside the Ingolf area south west of the Feeroes, taken the species at four

stations, but at the two only a few adult females.

Thor */6 1905 St. 72 57°52 L. N. 9°55 L.W. Yt. 1500 M. Wire 125 £2 (one with spermatophor).
21/6 1905 St.9go 47°47 L. N. 8°00 L. W. Yt. 300 M. Wire 139 f2 (one with spermatophor).

Distribution. This species has been recorded from the Mediterranean, and from the Atlantic
as far north as 55° L. N. 10° L. W.; it has been taken by the Monaco and by the Gauss Expeditions
in the Mid and South Atlantic; by the Gauss it has been taken at 45 L.S. 35 L.E. south of the Cape.
It was not taken by the Siboga, but Esterly records it from the Californian Bay, and based on some-
what too small material he draws the following conclusion (1912 p. 311) “evidently, the species moves
upwards at night if the numbers taken then as compared with those during the day can be taken as
representative of the whole population”.

I think we are right in regarding this species as in the main an Atlantic one, which frequents
the intermedial strata, but occasionally is found from the surface down to a depth of about 1000 meters.

Remarks. The described species is certainly identical with that described by Giesbrecht, in
spite of the larger size, the wanting seta of Le 2 of maxillulae and the structure of the spines in the
Basp. II pes IV. The male, which Cleve refers to this species, is possibly identical with mine; his des-
cription is too incomplete to settle the question at present. I think that Giesbrecht is right in refer-
ring the small Atlantic specimens of Z. Hesszt Brady to this species, the bigger ones may perhaps be

identical with £. vostromagna Wolf.

118 COPEPODA

32. Euchirella curticauda Giesbrecht.
(PI. IV figs 3a—m; Pl. VIII, figs 2a—c; text-figs 29 a—e.)

1888, Euchirella curticauda n. sp. Giesbrecht, p. 336. 1905. Euchirella curticauda Giesbr. Farran, p. 35.

1892. — _ Giesbr. Gicsbrecht, p. 233, taf. 15, 36. | 1906. _— : — — Ksterly, p. 59, pes 9, 10,

1898. — -- — Giesbrecht & Schmeil, p. 36. 12—13,.

1902. _ — — J. CG Thompson, p. 18. 1906, _ = — Pearson, p. I5.

1904? - _ -—— var. atlantica n. var. Wolf- | 1908. _ _ — vy. Bremen, p. 48, fig. 54.
enden, p. 116. 1908. — _ — Fearran, p. 38.

1905? — atlantica n. sp. Wolfenden, p. 20. 1909. _ — — A. Scott, p. 55.

1905. oo curticauda Giesbr. G. O. Sars, p. 4. IQII. -= — — Wolfenden, p. 236.

Description. {£9. Size: Specimen from Thor St. 88 426 mm.; anterior division measured 3°61 mm.;
urosome 065 mm. Gie'sbrecht’s specimen measured 35, Farran’s 43—48.

The head has a prominent rounded frontal keel (PI. IV fig. 3a); the frontal organ is fairly pro-
minent at the base of a low prolongation downwards from the keel; the rostrum, which is only visible
from beneath, is short and undivided, but sometimes asymmetrical with an accessory tooth on the right
side. The articular membrane between the head and the first thoracic tergite is indicated in some spec-
imens, but is completely wanting in others. The posterior margin of the first to fourth tergites is
strongly chitinized, and falls on each side naturally into a lateral and two median divisions; behind the
hinder margin of the fourth tergite and partly covered by it, the fifth thoracic tergite, hollowed like a
gutter, is found. The cephalosome is about 6°5 as long as the abdomen. The genital somite is distinctly
produced below, and has, on each side of the vulva, a lateral projection, generally visible from the side;
along the hinder margin of this somite is a marginal seam. The axtennudae almost reach to the end of
the genital somite, the appendages are as in Z. messinensis, but the measurements are distinctly different,
as the distal segments are comparatively shorter; the 8g segments, f. inst, are about as long as seg-
mient 15, not much shorter. The ex¢enna is in its main features like Giesbrecht’s fig. 3 Taf. 15, but
a distinct articulation is found between ReI and Re II. The maxillulae stand as pointed out by Gies-
brecht, between £. rostrata and messinensis; the Le 1 has g setae, but the Lir has, as in messinensis,
only 3 posterior setae, and the Li 2 4 strong setae; the Li 3 and basipodite 3 are also like this species,
but the Ri has 3 setae only. The maxzillifes has, exteriorly, near the tip of the anterior surface of the
second basipodite, as mentioned by Giesbrecht, a characteristic knob-formed process.

The margin between Se 1—2 of Re IwII in the frst pair of legs is only slightly concave, with
a minute pore. The Zes // (text-fig. 29 a), which has 26 teeth in the St, has a well developed first Se
in Ri, and the same number of secretory pores as in the preceding species. The fes /// has a distinct
accessory tooth at the base of Se Ril; the glandular pore in Re I seems to be wanting (text-fig. 29 b).
The number of spines interiorly on the posterior surface of basipodite II in pes 7V varies from 7 to 13,
and is most often different on the two sides; the accessory tooth of Se Ril is smaller; the secretory
pore in the ReI is sometimes indicated. ;

The anterior surface of the /abrwm is like that of Zivostrata. The chitinous system which
supports the oral surface of the labrum attains a characteristic development, as seen in fig.3¢, as
the anterior bars are directed towards the middle, almost touching each other, and almost encircling the
median circular spot Nr. 3. The groups of setae in the longitudinal series show a characteristic ar-
rangement: the jirst group consists of an area covered with about 30 short strong spines; the

Se ee eS ee CP re

COPEPODA 119

second group is represented by a longitudinal row of about 20 minute spines; the ¢hird group (cf.
Pl. IV fig. 3c) consists of 5 fairly long and slender setae placed more forwards, and lateral, and of 2—3
placed more inwards and backwards; the fourth group, which consists of 20—25 fairly strong setae,
has a characteristic shape, as it is convex, and has its right and left parts converging towards the
middle, and almost touching each other in front; the 7h group is a continuation backwards of the
fourth, and consists of about 30 more delicate setae. Behind this group an oblique, almost transverse
row of short “spines” is observed. Behind the central spot Nr. 3 no transverse row of setae is ob-
served, but behind Nr. 4, which is single, two transverse rows of rather delicate setae are observed.
The lamina labialis (fig. 3d), which is distinctly granular, is indistinctly divided into three parts. In
front of it, in the middle, is a longitudinal row of short spines on each side, followed by the two areas
of acicules, forming a curvature corresponding to the outer row of setae (cf. fig. 1c); the latter is single
behind, double in front, as a lateral row of shorter setae is found. The arrangement of the spinous
areas behind the lamina as well
as of the series of hairs on the
labial lobes is seen in figs 3d—e.
The intestinal tract is
almost straight, with a short
restriction between the anterior
and posterior divisions, and with
a slender coecal sac in front.
fg. Size of male from

Thor St. 88 3°73 mm1.; anterior di-

vision 2°92mm.; urosome o'81 mm.

Text-fig. 30. Zuchirella curticauda Giesbr.

The head has a distinct a. £9. Pes II sin. in ant. view <4o. b. £9. PesIII xc. 40. c. yQ (stage V). Pes III

Xc.40. d. yo (stage IV, a single specimen from Thor 2/6 1905 St. 88 not men-
tioned in the text). Pes III sin. xc. 50. e. yQ (St. V). Pes V 60.

frontal keel (fig. 3f), somewhat
longer and lower than in the
female; the body is rather elongate, and attenuated in front as well as behind. The head and the first
thoracic tergite are completely fused; the articular membranes between the thoracic tergites are like
those of the females. The anterior division is 3:5 as long as the urosome; the genital pore is found
on the left side of the first abdominal somite; the furcal rami are short, rounded, and about as long as
wide; their St. 2 is a little longer than the abdomen, and almost twice as long as the Si.

The antennulae extend a little beyond the end of the cephalothorax; the segments 2 and 3, 4
to 7, 89 and ro as well as 11 to 14 are more or les fused; the segments 20—21 are completely fused
on the right side, well separated on the left side. The appendages are scarcely different from those of
£. messinensis; they are as a whole more soft-skinned than in the female, and the Sp. of segment 23
is much shorter than that of segment 24. The segment 2 is almost rz as long as segment 17, which in
length is equal to 15, 16 and 19, and.about rr as long as segments 8&9. Segment 20 is on the left
side about as long as 8~9, but 20~ 21 on the right side combined is the longest segment, and almost
14 as long as segment 2. The aztennae have the Re1's as long as Ri, and have well developed distal setae;
the Re I and II are well separated, but the medial tooth of Re lis wanting. The Le of the maxzllulae

120 COPEPODA

possesses 9 setae, of which the 2 proximal ones are extremely short, the third one is distinctly shorter
than the strong powerfull S 4—9, of which again S 6—7 are the longest. The Lil is well developed
but has only a few short soft appendages; the Li I—II were not observed; the Basp. III (?) is quite
rudimentary, with at least a single almost rudimentary seta, and the Ri I—III (Basp. III?) bears 4 stiff
fairly long plumous setae. The Re has 10 well developed plumous setae in addition to an inner quite
rudimentary one. The maxzliae, have as seen in fig. 3h, in the main preserved the shape in the female
and so has the maxillipes, which is however much more slender, and it has preserved the knob-shaped
process of the second basipodite, though it is less prominent than in the female.

The frst pair of legs (PI. VIII, fig. 2a) is distinctly different from that of the female; the anterior
surface of the Ri has the process, which is situated laterally at the end of the chitinous list, forming the
margin of the rounded lobe, more prominent and perforated by about 3 canals for delicate ducts; between
the Re I and II a distinct articulation is found; the Se Re I is short, delicate and swollen at the base; the
outer margin of Re II is almost straight, with a distinct pore placed somewhat beyond the middle;
the pore in the outer margin of Re III, which is scarcely indicated in the female, is well developed,
and placed somewhat beyond the middle. The jes // differs by well developed articulation between
RilI and IIewIII, and by the comparatively short Se Re I and the es /V with the smooth inner margin
of the second basipodite. The 7th pair of legs shows similarity not only to that of & messinensis
but also to that of Z. rostrata; the two legs are almost of equal length (figs 3 g—i). The Jes dext. has
a rather short second basipodite, partly fused with the corresponding one of the left side, and a long strongly
enlarged third basipodite, which has an inwards process, which bears the rather slender Ri (Pl. VIII
fig. 2c) extending somewhat beyond the end of Re I~wII; it is most narrow in the middle, extending,
as well, towards the base, but especially towards the tip, and the anterior surface is slightly concave,
with the lateral margin somewhat turned over inwards; the lateral margin has two distal processes, of
which the one is placed near the tip. The Re I—II is long and slender, without distinct processes. The
Re III is as seen in fig. 3j irregularly curved, and has near the base a plate-shaped process; in the distal
half the inner margin possesses a few big teeth, and a more distally dense serration. The /e/ leg has
the basal segments long and slender, as seen in fig. 3i; the obtuse and slender Ri extends somewhat
beyond the proximal third of the Re I. The ReI is moderately long and slender; it bears a delicate
Se at the base of Re II; the Re II is rather short, and apparently excavated outwards and back-
wards (fig. 3 m); interiorly it is produced into a somewhat hairy process; at the base of this process is
the slightly curved, attenuated but blunt Re III (fig. 31 seen from in front and from the inside), which
inwards has two hairy processes basally, and terminally a marginal seam of short hairs.

WS (St. V). Size of female from Thor St. 88 was 363 mm.; anterior division 3:06 mm.; uro-
some 0'57 mmm.

The body is more slender, and the abdomen consists of 4 somites without any difference between
the first somite in the male and the female. The aztennae of the female are scarcely different from
those of the adult, except by the Ri, which is one fourth as long as Re, but they are distinctly diffe-
rent from those of the male, in which the Ri is almost half as long as Re, well developed and pos-
sessing 5 well developed setae in Le and 3 long + 2 rudimentary ones in Li, a number which is smaller

than. that of the adult male (6+ 7), and bigger than that of the female (3+ 2). The legs are in minor

COPEPODA I2I

features different from those of the adults; the Re III has no secretory pore at the base of Se I; the
outer tooth of RiI pes II is blunt, and the corresponding accessory tooth of pes III is just indicated
(text-fig. 30c). The inner margin of the second basipodite is smooth in the male, but has in the female
about 10 short delicate but rather stiff bristles. The jes V is similar to that of Z& rostrata, but there
is no indication of subdivision of Re; the terminal spine of Re dext. is longer and less sharply set
_ off, and that of left Re is much shorter (text-fig. 30 e).
_ Variation. In a single male the exopodite of the second foot was curiously transformed, as seen
in fig. 2b (Pl. VIII).
Occurrence. The Ingolf Expedition has not taken any specimen of this species, but the Thor

has gathered it at the following stations.

In Denmark Strait:
19/5 1904 St. 152 65°00 L. N. 28°10 L.W. Yt. 1000 M. Wire 1 fo.
20/6 1904 St. 153 65°20 L. N. 27°12°5 L. W. 3 £2.
21/6 1904 St. 154 65°27 L. N. 27°10 L. W. 1 f9.

In the Atlantic south of Iceland:

9, 1904 St. 178 63°08 L. N. 21°30 L.W. Yt. 750 M. Wire rio.

10/, 1904 St. 180 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 1 f9.

m/, 1904 St. 183 61°30 L. N. 17°05 L. W. Yt. 1800 M. Wire 14 £9 (3 with spermatophors).
25/, 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 10 f?.

/, 1904 St. 285 62°49 L. N. 18°44 L. W. 13 £9.

29/3 1905 St. 164 61°20 I. N. 11°00 L. W. Yt. 300 M. Wire 16 f2 (5 with spermatophors).
22/; 1904 St.g9 61°15 L.N. 9°35 L.W. Yt. 1400 M. Wire 1 yc (V). .

12/, 1904 St.78 61°07 L. N. 9°30 L. W. 2 £9.

Outside the Ingolf area south-west of the Feeroes a fairly large number of specimens has been

captured.

5/6 1905 St.82 51°00 L. N. 11°43 L.W. Yt. 1200 M. Wire 1 £2, 3 fo, ry? (V).
Yt. 800 M. Wire 11 £9 (3 with spermatophors).
"/y 1905 St. 167 57°46 L. N. 9°55 L.W. Yt. 1500 M. Wire 16 £9? (5 with spermatophors).
8/6 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 309 M. Wire 51 £9, 1fd, rych (V).
20/5 1905 St.88 48°09 L.N. 8°30 L.W. Yt. 300 M. Wire 200 f? (30 with spermatophors), 7 fd,

: 2y? (V), 2ydh (V).
2t/6 1905 St.90 47°47 L.N. 8°00 L.W. Yt. 300 M. Wire 5 £9, 1 fd.

Distribution. “This species” is according to Farran “of frequent occurrence, and often moder-
ately common” on the west coast of Ireland “at depths of from 200 to 1000 fathoms”. It has been taken
by the Monaco Exp. and by the Gauss’ Exp. as far south as c. 10° Lat. S. It has been recorded from
the Bay of California and from the Malay Archipelago.

Remarks. This species is certainly identical with that described by Giesbrecht and Esterly,

though it is somewhat bigger, and in spite of some features, e.g. shape of fifth thoracic tergite, which

The Ingolf-Expedition. III. 4. 16

122 COPEPODA

are not mentioned in Giesbrecht’s rather short description. The species is probably identical with
Wolfendens var. atlantica, as the differences set forth viz: “head separated from first thoracic segment”,
basipodite II of pes IV, which has “only six rather broad-based and long spines”, and the smaller size
(38 mm.) are not of much importance. It is more doubtful, if it is identical with Z aflantica Wolf, in
which the abdomen is only 1/s of the anterior division in length. Most probably the described male
belongs to this species, especially on account of the characteristic articular membranes of the thoracic
tergites, the frontal keel, the almost absolete rostrum and the knob-like process of the second basipodite
of the maxillipeds. The arrangement of secretory pores and the structure of Se of Ril in the legs are
like those of the females. Some of the differences are certainly due to sex, f. inst. longer abdomen,
longer endopodite of antennae with greater number of setae; a few of the other differences are not
quite the same as those found in related species, but it must be remembered that sexual differences

are apt to vary from the one species to the other.

33. Euchirella messinensis Claus.
(Pl. IV figs 2a—c; Pl. VIII fig. 1; text-figs 31 a—f)

1863. Undina messinensis n.sp. Claus, p. 187, pl. XXXI. 1904. Euchirella messinensis Claus. Cleve, p. 190.

1892. Euchirella messinensis Claus. Giesbrecht, p. 232, taf. 15 | 1905. _— —_ — Esterly, p. 151, fig. 18.
& 36. 1905. — ~ —. G.O.Sars, p. 4.

1894. Nec. — - — Th. Scott, pp. 45—46. 1908, —- — — Farran, p. 37.

1896. _ _ — Canu, p. 424. 1909. — — — Pesta, p. 23.

1898. _ -— — Giesbrecht & Schmeil, | 1909. — — — A. Scott, p.56.
p. 31. IgI2. _ _ — Pesta, p. 13.

1903. — >= — Giesbrecht, p. 201. IgII. _ _— — Wolfenden, p. 237.

1903. _— _ — Thompson & Scott, p.244.

Description. f9. Size of specimens from Thor St. 183 5°7 mm.; anterior division 4°5 mm.; uro-
some 12mm. Giesbrecht’s specimens measured 4°75 mm.

The sac-shaped protuberance of the genital somite, which is rather variable in the specimens
examined, differs somewhat in shape from Giesbrecht’s fig. 18 (Taf. 36); it is distinctly widened out
towards the end, does not reach much behind the end of the third somite and beyond a distinct con-
cavity at the right side the tip is directed towards the right; the protuberance is dorsally excavated.
The Ri of the antennae possesses 5 setae in Le and 3 (not 4) in Li. The frst pazr of legs has the outer
margin between the Se of Re I—II almost straight with a distinct pore, continued into a conical
process at least in one specimen. The glandular pore in the outer margin of Re III pes I is placed */,
of the length of Re III measured from the base. The number of glandular pores is as in £. rostrata;
in the Re I exteriorly distinctly removed from the tip a transverse split (secretory pore) was observed
not only is pes II but also in pes III—IV, in which the real pore is found; a similar one was observed
in Basp, III medially to the insertion of Se I, and in Re III near to the insertion of Si 4.

Somewhat behind the insertion of the antennulae a well marked elevation is found, which is
well separated from the labrum proper by an anteriorly convex chitinous line; in connection with
the mentioned elevation as well as with a transverse chitinous bar behind the mouth a strong
chitinous system forming a covering for the manducatory part of the mandibulae is found. The an-

terior surface of the /adrum does not possess any setae in front of the marginal row; this consists, on

COPEPODA 123

each side of the median concavity, of a medial transverse row of about 25 more spine-shaped setae.
The chitinous system of the oral surface of the labrum (fig. 2a) shows as seen in figures (cf. 3c) some
similarity to that of Z. curticauda, but the arrangement of the groups of hairs in the longitudinal
series is distinctly different, and is indeed very characteristic. The first group consists of about 30—40
setae, placed in a single inwards convex row; the second group, which is perhaps fused with the lateral
group, is represented by a big group of minute acicules; the ¢hivd group consists of about 20 fairly
long setae, and is converging towards the front; the fourth group, consisting of about 25 fairly strong
setae, has the anterior portion placed almost transversely, and is almost fused with corresponding part of
the other side; the 7th group, which consists of about 4o rather slender setae, is partly fused with the

fourth; the sixth group is transverse, and consists of short delicate hairs. No transverse series of

c

A
:

spinules is observed behind the median circular spot Nr. 3, x
and the two series behind the fourth median spot are fused
to a square area, beset with spinules.

The Jamina labialis, as seen in fig. 2b, is smooth and
very insignificant; the arrangement of setae in front of lamina
is, as seen in fig. 2c, somewhat different from that of &. cur-
ticauda. Behind the lamina 3—4 spinous areas are observed Q

b d

on each side. The series of hairs behind and upon the labial

lobes show a rather regular arrangement, as seen in fig. 2c,
the medial posterior groups of a few hairs could not naturally
be referred to any of the series. The frst series consists of a

number of short hairs, placed in a rounded area; the second Text-fig. 31. Zuchirella messinznsis Claus.

: é 2 a—b (to the left). £2. Ri pes II—III x 57. c. Pes
series consists of two rather independent almost transverse vy dext; ridges of Re HI X175. d—e (in the
middle below) yo (St. V) Ri pes II—III X 57.

f. yo. Pes V ant. view X 57.

f

rows; the ¢hzrd series seems only to be represented on the
labial lobes, and the fourth one has in addition to the regular
row on the lobe a more medial and posterior portion; the 7th groug, which consists of somewhat
stronger setae, falls naturally into a median portion which is fused with the corresponding part of the
other side, and a lateral one which is.continued to the end of the labial lobe.

3. Size of specimen from Thor St. 183 546 mm.; anterior division 4°37 mm.; urosome 10g mm.
Giesbrecht’s specimen measured 3:95 mm.

The frontal keel is distinctly higher than figured by Giesbrecht (Taf. 36 fig. 25). The oral ap-
pendages are practically like Giesbrecht’s description, but the mandibulae possess as in Luch.
rostrata a well developed manducatory portion; the labrum and labium show a similar development
as in this species.

According to Giesbrecht (p. 240) the only difference between the natatory legs in males and
females is found in the completely smooth inner margin of the fourth pair of legs in the males; in
my specimens, however, the difference is even better marked than in & rostrata and curticauda (PI.
VIII fig. 1). The articulation between Re I and II pes I is indicated, but the Se Re I is wanting;
the Se Re II is quite rudimentary; the pore in the outer margin of Re II is well developed, but

that of Re III seems to be wanting: The St. of the Re III pes II has about 50 instead of c. 25 teeth.
16*

124 COPEPODA

The fifth pair of legs is scarcely different from Giesbrecht’s fig. 2t (Taf. 15); the teeth along
the inner margin of Re III pes V dext. correspond really to transverse keels, as seen in text-fig. 31 ¢.

xg (Stage V). Size of male from Thor St. 88 419 mm.; anterior division 3:29 mm.; iro-
some 0'90.

The shape of the body is in the main as in adult female, without frontal keel. The appendages
are in the main like those of the adult female, except the antennae; these organs show similar dif-
ferences as in £. curticauda; the antennae of the female is in the main like those of the adult, with
rudimentary Ri, which, however, has the setae of Ri 2 better developed (in Li 4 setae); the antennae
of the male are like those of the adult by the more powerful Ri, which, however, only reaches the middle
of Re 2, and has a similar number of setae as in the female. The zatatory legs differ somewhat from
those of the adult by the less developed Se of Ri I, as seen in text-figs 31d—e, as well as by the wanting
glandular pore at the base of Se 1 Re III. The inner margin of the second basipodite in the fourth
pair of legs is smooth in the male, but has in the female about 6 short delicate bristles. The /i/th pair
of legs has, as seen in text-fig. 31f, a characteristic structure resembling that of the adult male.

Occurrence. The S/S Thor has gathered a few specimens of this species at the following
stations:

1t/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 5 f9.
24/6 1905 St.93 49°25 L. N. 12°20 L. W. Yt. 200 M. Wire 1 £9.
5/6 1905 St.82 51°00 L. N. 11°43 L.W. Yt. 1200 M. Wire 2 £9, 1 yh (V).
800 M. Wire 2 f9, 2f¢.
20/6 1905 St.88 48°09 L.N. 8°30 L.W. Yt. 300 M. Wire 2.£9, rfid, 1 y?(V), r yc (V).

Distribution. The species, according to Farran, is fairly common on the west coast of Ireland
“at depths of from 350 to 700 fathoms”. It has been recorded from the North-east Atlantic, the South
Atlantic, the Mediterranean, the Malay Archipelago and the Pacific (Bay of California).

Remarks. In spite of the mentioned small difference the female must be regarded as identical
with £. messinensis; if the difference in the first pair of legs between my male and Giesbrecht’s is

really a constant one, the identification of the males seems to be rather doubtful.

*

34. Euchirella intermedia un. sp.
(PL IV figs 4a—c; Pl. VIII fig. 3; text-figs 32 a—f)

1g02? Euchirella carinata n.sp. Wolfenden, pp. 366—367.
Ig11? Euchirella gracilis n. sp. Wolfenden, pp. 237, text-fig. 22, tafel XXVII figs 8—1o.

Description. £9. Size of specimen from Thor St. 82 566 mm.; anterior division 466 mm.; uro-
some I mm.

No frontal keel is found; the short strong rostrum is directed forwards and downwards
(cf. text-fig. 32e). The articular membrane between head and first thoracic tergite is present laterally;
the articular membranes between the thoracic tergites show similarity to those of Auch. curticauda;

the fifth somite is laterally indicated as a mere marginal seam, and the lateral corner is rounded as
seen in fig. 4a.

COPEPODA 125

I
46
as the fourth somite, and about as long as wide. The genital somite, which is as deep as wide, is

The abdomen, which is — as long as the anterior division, has the furcal rami about as long
somewhat wider than long; in dorsal view it is distinctly asymmetrical and more convex on the left
than on the right side; on the left side, near the hinder margin, we observe a lamellous process with
broad base, and directed backwards and somewhat outwards; behind this, as seen in fig. 4a, another
less prominent elevation was observed. The genital area is well produced in front, and the median
prominent crista, which is prominent in Giesbrecht’s fig. 21 (Taf. 36) of Z. venusta, was not seen.
The triangular teeth along the hinder margin of abdominal somites 12, 3 and 4 are only poorly
developed.

The antennulae reach the end of the body, their appendages are scarcely different from those
of EZ. messinensis, and the measurements are very much alike. The endopodite of the atennae is about
half as long as the exopodite, and its second segment has 9g setae in Li and gin Le. The Re I, which
has a well developed conical process without any seta, is fairly well separated from Re 2 (Pl. VIII
fig. 3). The maxillulae differ from those of Euc. messinensis by the presence of a less powerfull Sa in
Ril. The maxillae have the outer margin rather suddenly produced as in £. vostrata, but are in other
respects scarcely different from Z. messinensis; the maxillipeds differ from those of the latter species
by the almost straight exterior margin of the third basipodite. The glandular pore in the outer margin
of Re III of pes I is more removed from base, in other respects the first pair of legs is like Z. mes-
sinensis. The Se of Ri I of pes II is more prominent than in &. messimenszs (cf. text-fig. 31a); the ac-
cessory tooth of the Se Ril is indistinct in pes III, and completely wanting in pes IV. As in Z cur-
ticauda no glandular pore was found in Re I of pes III—IV. The second basipodite of the fourth pair
of legs has only a single strong spine, extending to end of segment (text-fig. 32 a).

The /abrum is in lateral view like that of Luc. messinensis; its oral surface (fig. 4b) is in
structure lying between that of & messinensis and curticauda (fig. 2a and 3c). The first group consist of
an area with densely placed, fairly strong spines; the second group is represented by 2—3 longitudinal
rows of short teeth, laterally to which a similar longitudinal row is seen; the ¢hird group consists of
about 5 fairly long spines, placed medially to and partly in front of the posterior part of second group.
Behind the median spot Nr. 4 a square area of small spinules and a posterior transverse row are found.
The lamina /abialts (cf. fig. 5 f) is like that of Z maxima Wolf. but is more distinctly granular posteriorly.
The area in front of lamina labialis is like that of Z. messimensis, and so is the area behind, which,
however, in the posterior groups shows some not quite unimportant differences.

fg. Size of male from Thor St. 88 5:3 mm.; anterior division 4-2 mm; urosome II mm.

The body is distinctly more slender than in the female. No frontal keel is found, but the
rostrum is longer and directed more downwards (text-fig. 32 b); the lateral corners are rounded, and the
fourth and fifth thoracic tergites are completely fused. The asdomen is distinctly one fourth as long
as the anterior division. The furcal rami are a little wider than long; the serrated seam along the
hinder margin of somites II—IV is fairly well developed.

The antennulae extend to the end of the abdomen; the appendages are scarcely different from
those of Z. messinensis; segments 89 are completely fused with segment 10; segments 12 and 13, 14

and 15 are more or less fused. The exopodite of the aztennae is 14 as long as the endopodite, the

126 COPEPODA

Le of which has 5 setae, while its Li has 7 setae. The maxzllulae are scarcely different from those
described in £. curticauda; the maxillae agree in general shape (cf. fig. 3h Pl. IV), but the setae of the
four proximal lobes are poorly developed, while the fifth lobe has a long, soft, somewhat contorted sensory
seta in addition to one fairly slender and one very short of usual structure; the maxzllipeds are as
usual more slender than in the female.

The first pair of legs is as usual well distinguished from that of the female; the first and
the second outer segments are marked off from each other by a small incision, proximally to which the
short, at base swollen, Se is found; the Se of Re II is short and moderately slender; the position of

b the glandular pores in the outer margin
of Re II and IIT is as in the female. The
third pair of legs differs by the better
developed accessory tooth of the Se Ri
I, and the fourth pair by the smooth
inner margin of the second basipodite.

The fifth pair of legs is much longer
than the abdomen, and extends almost
to the end of the furcal setae; both
legs are very similar to those of 4. mes-
sinensis (text-figs 32 c—d); the processes
on the margins of the rami of the right
leg are slightly different from those of

the mentioned species. The right endo-
a d c f
Text-fig. 32. Zuchirella intermedia n. sp.
a. £9. Pes IV sin. in post. view X33. b. fo. Head X 135. ¢ fo¢. PesV exopodite is terminated by three some-
in post. view X 145. d. fo. Pes V sin. X 275. e yQ (St. V) head X 33.
f. yo (St. V) pes V in anterior view X 57.

podite seems to be wanting; the right

what hirsute processes (cf. text-fig. 32 d),
of which the first is hook-shaped with
three teeth, the second is flat and rounded, while the third one is slightly hook-shaped without serrations.
we (St. V). Size of female from Thor St. 88 4°78 mm.; anterior division 3°91 mm.; urosome 0°87 mm.
The shape of the body is practically like that of the adult female with the usual differences
in the shape of the abdomen; triangular teeth are found along the hinder margin of somites IJ—III.
The only difference of importance which was observed in the mouth appendages was found in the
antennae, which in the female as well as in the male is like that of the adult female, but in Le Ri
only 6 setae are found and in Li 7. The Se of Ri I is blunt, and only slightly prominent in the
second pair of legs, and its accessory tooth is almost obsolete. The inner margin of the second basi-
podite in the fourth pair of legs is smooth in the male as well as in the female. The fh pair of
legs of the male shows (text-fig. 32 f) on the one side a distinct similarity to that of Z messimensis, but
is on the other side distinctly different, f. inst. by the short rounded left endopodite.
Occurrence. The S/S Thor has gathered this species at two stations viz:
15/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 800 M. Wire 219, 19 y? (V), 2 yh (V).
20/, 1905 St. 88 48°09 L. N. 8°30 L. W. Yi. 300 M. Wire 1 fd, 2 y? (V), ryd (V).

ee a ae

COPEPODA 127

Remarks. The male of this species is very similar to Z. pulchra Giesbr., while the female seems
to be nearly related to &. venusta Giesbr., but is distinctly different by the shape of the genital somite, the
larger size, the much longer endopodite of the antennae with greater number of setae and the single
spine in the second basipodite of the fourth pair of legs. It is possibly identical with Wolfenden’s
E. gracilis (p. 237 1911) from the South Atlantic, which agrees with it in several of these characters, as
far as can be seen from the short description, but as the genital somite in dorsal view has a different
outline and laterally is “ohne Auswiichse”, and as the endopodite of the antennae has 8-+ 7 terminal
setae, I feel justified in regarding my species as a new one. Between Wolfenden’s description of a
young male of & carinata and this species there is some similarity.

In spite of the somewhat curious difference found in the number of setae in the endopodite of
the antennae I do not doubt that the young specimens belong to the same species. In all features of
importance, even the wanting glandular pore in Re I of pes III—IV, they aggree with the females.

In several respects this species bears similarity to &. curticauda Giesbr.

35. Euchirella maxima Wolf.
(Pl. IV figs 5a—h; Text-figs 33 a—i.)
1905. Euchirella maxima n. sp. Wolfenden, p. 18, pl. VI figs | 1909. Euchirella maxima Wolf. A. Scott, pp. 57—58, pl. XII
; g—Il. figs 12—20.
1908, — — Wolf. Farran, p. 38. IgII, — _ — Wolfenden, pp. 238—239, taf. 28
| figs 3—5; text-figs 24 a—b.

£9. Size of specimen from Thor St. 88 was 78 mm:¥%anterior division 6°5 mm.; urosome 13 mm.
A specimen from Thor St. 167 measured 8:5 mm. Wolfenden’s specimen measured 7°5—8-7 mm.

The head is mounted with a well marked frontal keel. The rostrum is short, undivided and
in lateral view almost triangular. The first thoracic tergite is fused with the head. The fifth thoracic
tergite is, as stated by Scott, well separated from the fourth; it is narrow above, but below it is widened
out, and on the left side produced into an irregular, rounded lamina (fig. 5 b), but on the right produced
into a somewhat shorter pointed process (fig. 5c); this interesting structure, which is rather variable
within the different specimens, has not been described by previous authors. The articular membranes
of the thoracic tergites are developed in a similar way as in Z. curticauda. The abdomen is only one
fifth of the anterior division; the somites are short and dorsally along the hinder margin have short bristles.
The lower surface of the genital somite (fig. 5d) is produced, and has, somewhat in front of middle, on
the left side, a prominent pointed process, which is curved forwards and inwards. On the left side and
behind, a small protuberance, scarcely visible from above, is seen, and on the right a small anterior
process and a fairly prominent bigger one, which is placed more posteriorly and is partly visible in
dorsal view. The furcal rami are about as long as wide.

The antennulae reach about to the end of the genital somite; the segment 17 is about as long
as segment 2 and 1°6 as long as segments 8&9 and segments 24—25. The endopodite of the avtennae
is only "/; of the exopodite; its Le of the second segment has only 3 moderately long almost naked
setae, and the Li has 5 somewhat shorter ones (the number of setae is according to Wolfenden as well
as to Scott 5+ 5); the Re I—II is distinctly longer than Re III—VII; the Re I, which has a pro-

128 COPEPODA

minent conical process without hair, is well separated from the Re II, which possesses a basal, a median
and distal short conical protuberance without any hairs (the 2 first are shown in Scott’s fig. 17). The
Le of the maxzllulae possesses 8 setae, of which the 3 basal are rather short and delicate, and the fifth
moderately long, but much shorter than the fourth as well as the following one, which are long
and powerful; the number of setae is else as in the Z. curticauda. The maxillae differ from those of
£. messinensts by somewhat stronger spines and more pronounced spinulation on the posterior surface
of the lobes. The maxillipeds are most like those of EZ. curticauda; the third basipodite is 2°5 as long
as the Ri, which has 4 setae in the Ri 2.

The first pair of legs is scarcely different from that of £. curticauda; the second pair of
legs has a well marked tooth in RiI, and the Se Re II extends as shown by Wolfenden at least
to the tip of Se I Re III; the ¢hird pair of legs has the accessory tooth, corresponding to Se Ri I pointed
and well developed; the second basipodite of the fourth pair of legs, which is strong, broad and of
triangular shape, extends barely to the end of the somite, and seems, as figured by Scott fig. 20
Pl. XII, to be formed by the fusing of about 4 spines. The pores are like those of & messinensis.

The /abrum (fig. 5), as seen in figure, has the inner marginal row well developed, but the
outer one seems to be represented by a few minute granules. The oral surface is in all main features like
that of Z. curticauda, but differs as seen in figures, as f. inst. by the third group, which is not conver-
ging but diverging posteriorly. The damina /abialis (fig. 5) is striated but not distinctly granular; the
area in front of the lamina is rather similar to that of Z curticauda (ct. fig. 3d), but the lateral series,
which forms the continuation of the serrula 6-dentata, has only a single row of fairly strong spines,
and the inner series has about 25 short spines in a single row in addition to the usual area covered with
acicules, which starts behind the end of the inner series. The arrangement of setae behind the lamina
labialis and at the labial lobes (fig. 5 g) is, as far as series III—V are concerned, practically like that
of the preceding species, but as far as the first series is concerned is rather different.

£9. Size of specimen from Thor St. 167 was 67 mm.; anterior division 5:1 mm.; urosome 1°6 mm.

The body (text-figs 33a—b) is moderately slender; the head and first thoracic somite are com-
pletely fused; the lateral corners are rounded, and the fourth and fifth somites are completely fused.
The head is surmounted by a fairly big, prominent, rounded, keel and has a short, strong, compressed
and undivided rostrum. The abdomen is about one third as long as the anterior division; the first and
second somites, which are of equal length are somewhat longer than the third, and about as long as the
fourth; the serration along the hinder margin of somites II—IV is short and delicate. The furcal rami
are about as long as wide; the St. II, which is distinctly longer than the abdomen and twice as long
as Si, is longer than St. I—III, and again longer than St. IV.

The antennulae extend to the end of the second abdominal somite; they are in most respects
like those of £. curticauda. The exopodite of the antennae, which has an indication of a protuberance
in Rel, is 14 as long as the endopodite, which possesses 5 setae in Le and 7 setae in Li.

The mazxillulae possess 8 setae in Le, completely like those of the female; the LiI and II are
fairly well developed, and possess a few soft contorted appendages, and the Si of the Re is fairly long,
but in other respects the appendages are scarcely different from those of & curticauda; the maxillae

and maxillipeds are practically like those of the preceding species.

COPEPODA 129

The first pair (text-fig. 33 c) of legs is in most respects like that of Z curticauda; the process
on the anterior surface of Ri with 3 teeth, perforated by delicate canals, is almost obsolete; the Se of
Re I is fairly long and slightly swollen at the base; the pore in the outer margin of Re III is placed
distinctly nearer the base than the middle. The ses 77 shows a similar difference as that of & curti-
cauda, with fairly well developed articulation between RiI and II and comparatively short Se Re II.
The jes JJJ—IV are like those of the females, but the inner margin of the second basipodite in the
fourth pair of legs is completely smooth.

The fi/th pair of legs (text-figs 33 b and e—g) shows most similarity to that of Z curticauda; the
right and the left legs are of almost equal length; the Ri dext, which extends almost to the end of
Re IwII, is terminally inflated, and outwards has two rounded processes in the middle; the Re III is

Text-fig. 33. Zuchirella maxima Wolf.
a. fo. Head x 34. b. fo. Abdomen X20. c. fg. Pes I X66. d. fc, Pes IVsin. Ri X66. e fg. Pes V dext. Re II—III
X 66. £ fo. Pes V sin. Re III (from below) x 107. g. fo. Pes V sin. Re III (in exterior view) 66. h. yo. (stage V) Pes V
in ant: view X 33. i. yo. (stage IV) Pes V in ant. view X 60.

slender, gradually attenuated towards the tip and is in distal half, in a similar way as in Z. messinensts,
regularly serrated along the margin (text-fig. 33). The left leg has a long and slender Ri, which
extends to the end of ReI and terminally is rounded and slightly convex in its whole length; the Re I is
fairly long and slender, somewhat concave inside and here possessing a few protuberances; the Re II is
somewhat shorter, with a basal rounded process and 2 distal ones, of which the one is short and conical,
while the other is about one third as long as the segment, and gradually attenuated, the Re III, which
is distinctly half as long as the Re II and placed at the base of the last mentioned process, is trian-
gularly pointed beyond a distal conical process and hairy along inner margin proximal to it (text-
fig. 33 f).

4g (St. V). Size of female from Thor St. 88 is 6:04 mm.; anterior division 4:96 mm,; urosome 108,

The shape of the body is like that of the adult, but the frontal keel is somewhat lower; the
lateral corners are rounded (fig. 5h), not produced, and the fifth somite is dorsally as well as laterally

represented by a mere seam, The abdomen is about one fourth as long as the anterior division. The
The Ingolf-Expedition. III. 4. 17

130 COPEPODA

antennae of the female are scarcely different from those of the adult female, but for the presence of 5
setae instead of 3 in Le; the antennae of the male are more similar to those of the adult male, as the Ri
is half as long as Re and has 7 setae in Li and 5 in Le. In the maxillulae of the female the S 14 of
Lilis distinctly shorter than S 13; this structure is probably due to individual variation, as S 13 and 14
in the male are of equal length. The legs differ from those of the adult female by the less prominent
Se of RiI and by the completely smooth inner margin of the second basipodite in the fourth pair of
legs in male as well as in female. The “ih pair of legs (text-fig. 33 g) is distinctly different from
that of preceding species, as both Re as well as Ri are of almost equal length, and as the left leg is

distinctly pointed.

¥> (St. IV). Size of female from Thor St. 88 469 mm.; anterior division 4:0 mm.; urosome o'69.

The fifth thoracic somite was not marked out; the awtenmnulae extend a little beyond the end of
the abdomen. The antennae are practically like those of the female of the preceding stage, but the
Li of Ri has 6 setae; the Ri in the male, which has 6 setae in Le, is not distinctly longer than in the
female. The Re of the maxzllulae possess as usual in this stage 9 setae only. The frst pair of legs
has as usual Re I—III completely fused; the Se ReI is much longer than Se Re II; the secretory
pore in the outer margin of Re II is wanting; while that in the outer margin of Re III is well deve-
loped; the pes II—IV show the usual differences; the inner margin of the second basipodite of the
fourth pair of legs is smooth in both sexes; glandular pores are in pes III—IV found at the base of
Se ReI and at the base of Se 3 Re III. The “/%/ fair of legs is very similar to that of Z. rostrata,
but the endopodites are comparatively longer, and the Re dext. is more elongated with fairly long St.

(text-fig. 33 i).

Occurrence. The S/S Thor has gathered this species in six samples viz:

/, 1904 St. 183 61°30 L. N. 17°08 L.W. Yt. 1800 M. Wire 1 y? (V).
5/6 1905 St.82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 6 y@ (V), 6y oh (V).
Yt. 800 M. Wire 1 yo (V).
™/, 1905 St. 167 57°46 L. N. 9°55 L.W. Yt. 1500 M. Wire 1 £9, r y@ (V), ryo (V).
3t/g — + _— — Yt. 300 M. Wire 2{¢.
8/6 1905 St.72 57°52 L.N. 9°53 L. W. Yt. 1500 M. Wire 2 f9.
20/6 1905 St. 88 48°09 L.N. 8°30 L. W. Yt. 300 M. Wire 4£9,1 y?(V), 6 yd (V), 5 yo (IV), 4 yP (IV).

Distribution. This species is recorded from five stations on the west coast of Ireland at depths
of from 350 to 1000 fathoms; it has been taken at a great depth by the Gauss Expedition in the South-
Atlantic as far south as c. 35° L.S. (5° L. E.), and in the Malay Archipelago by the Siboga Expedition.

Remarks. In spite of small differences, partly enumerated above, this species is certainly iden-
tical with that described by Wolfenden. I think that the described male is most naturally referred to
this species in spite of the comparatively small size, fairly long rostrum and rounded lateral corners of the
thorax, and especially on account of the shape of the frontal crest and the well developed accessory
teeth in Se Ril of pes III—IV.

ae 2 ih
Se ee ae

ee a a

COPEPODA 131

36. Euchirella bitumida n. sp.
(Pl. V figs 9a—g; Pl. VIII figs 4a—e; text-fig, 34.)

Description. £9. Size of specimen from Thor St. 82 66 mm,; anterior division 5:4; urosome 1-2.
Another specimen measured about 7 mm.

The head is produced into a prominent rounded helmet-shaped crista (Pl. VIII fig. 4a), like
that of Z galeata, which is well marked off behind, and not continued into a dorsal keel; below the
crest the margin falls steeply towards the prominent but rather short rostrum. The body is rather
slender, with the head and the first thoracic tergites coalesced; the fifth tergite is not distinctly marked
out, and the lateral corners are rounded (figs ga—b). The anterior division is 4'5 as long as the abdomen.
The genztal somite thas in dorsal view a better marked convexity on the right than on the left side,
and possesses, slightly in front of middle on each side, a rounded protuberance, bigger on the right
side and with a shallow impression between the two; the genital somite is in lateral view rather cha-
racteristic, partly on account of the ventral outline which is suddenly produced in front and falls rather
smoothly behind; in ventral view it appears rather simple (fig.gc). The caudal rami are about as
long as wide; the terminal setae, which are somewhat longer than the interior one,
are of almost equal length and a little shorter than the abdomen,

The antennulac, which almost extend to the end of the abdomen, have the
appendages completely like those of Z. messimenszs, and the measurements almost alike,
except segment 17, which is the longest segment, a little longer than segment 19.
The antennae (Pl. VIII fig. 4a) have the endopodite one third as long as the exopodite;
the endopodite has 6 setae of equal length in the Le and 6 in the Li, of which the
two inner are rather short. The maxillulae differ from those of Z. messinensis by the Text-fig. 34.
relative length of the setae in Le; the two first and the fifth one are distinctly ch. ditumidan.sp.

Yo. Pes V in an-

shorter than the others. The maxillae are, as seen in fig. 9d, in main features like sisees
terior view X 57.

those of Z. messinensis. The maxillipeds have the exterior margin of the third basi-
podite, which is 1-3 as long as Basip. I~ II and about twice as long as Ri, somewhat sinuated; the Ri II
has only 3 setae.

The frst pair of legs (fig. 4b) has a small pore in the almost straight margin of Re II, and
a very indistinct one placed near the base on the outer margin of Re III. The Se of Ril (fig. 4c) of
the undivided endopodite in the second pair of legs is poorly developed, as seen in fig. 4c, and the
Se of Re II extends slightly beyond base of Se 1 Re III. The accessory tooth of Se Ril is only in-
dicated in the third pair of legs (fig. 4d). The fourth pair of legs has on the posterior surface of
the second basipodite in the type specimen on the left side a single straight, fairly strong spine, which
almost extends to the base of the third basipodite, and on the right side is substituted for by 3 more
slender spines (fig. 4 e); in another specimen the spine was wanting on the right side; in a third specimen
a single spine was observed on the left side, while none was observed on the right side (perhaps
broken?); in two specimens a single spine was observed on both sides, and in a single one a spine
on the left and one on the right side.

The number of glandular pores is like that of Z. messinensis with a pore in Re I of pes III—IV,

17*

132 COPEPODA

The main difference between Z. messinensis and this species, found in the structure of the labrum,
is observed in the 2 first groups of the oral surface (fig. 9 e), which are fused to a single group consisting
of numerous short spinules. The /amzna dabialis (fig. gf) is distinctly granular; the arrangement of setae
in front of the lamina as well as of the spinulous areas behind it is in the main like that of Z. messz-
nensts. ‘The development of the series of setae behind and upon the labial lobes is, as seen by com-
paring figs 9g and 5g (Pl. IV), most like that of 2 maxima.

¥g (St. V). Size of female from Thor St. 88 was 466 mm.; anterior division 3°85 mm.; urosome
o81. A male from the same sample measured 4:99 mm.

The shape of the body is as in the adult female; the antennulae extend slightly beyond the
end of.the abdomen. The antennae are in the young female, scarcely different from those of the adult
female but in the young male the exopodite is twice as long as the endopodite, which is much more
powerful and has 7 setae in Li.

The second basipodite of the fourth pair of legs has in the middle on the inner- margin 3 rather
short and stiff hairs, while the margin is smooth in the male. The fh fair of legs in the male is
very much like that of & messinensis (cf. text-fig. 34), but the Re dext. is more regularly rounded, and
does not possess any terminal hair.

Occurrence. The Thor has gathered the species in four samples; the first locality is not quite
certain, owing to a mistake.

2/, 1904 St. 285 62°49 L. N. 18°46 L.W. Yt. ? » Wire® z £9.

5/6 1905 St.82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 6 f? (1 with spermatophor), 1 y? (V).
800 M. Wire 1 f9.

20/, 1905 St. 88 48°09 L. N. 8°30 L.W. Yt. 300 M. Wire 2 f9, 2 y? (V), ryoh (V).

Remarks. This species, of which I was not able to find any description in the literature, is
nearly related to Z. messinensis; in the shape of the head it provides some similarity to Giesbrecht’s

rather imperfect description of &. galeata, but his fig. 22 (Taf. 36) of the genital somite is very different.

37. Undeuchzte minor Giesbr.
(Pl. V figs 3a—g; text-figs 35 a—g.)

1856? Undina plumosa n. sp. Lubbock, p. 18, pl. IX figs 3—5. | 1904. Undeuchzete minor Giesbr. Cleve p. 198.
18839. Euchzete pulchra Lubb. Brady, pp. 63—64, pl. XIV figs | 1905. — _— — Esterly, p. 149, fig. 17.
6—9. —_ _ -- Farran, p. 35.
3? -- australis n.sp. Brady, p. 65, pl. XXI figs. 8—9 — australis Brady. G. O. Sars, p. 4.
1889. Undeuchzeete minor n. sp. Giesbrecht, p. 335. 1906. _— minor Giesbr, Pearson, p. 15.
1892. _ -- Giesbr, — p. 228,pl. 14and 37. | 1907. — — _ G.O. Sars, p. 3.
1893? Eucheete australis Brady Th. Scott, p. 58, pl. VI fig. 23. | 1908. _ _ — Farran, p. 37.
1895. Undeuchzte minor Giesbr. Giesbrecht, p. 251. 1908. — — — y. Bremen, p. 44, fig. 50.
1896. — _ — Canu, p. 424. 1909. _- plumosa Lubb. A. Scott, pp. 62—63, pl. XXII
1898. — — — Giesbrecht & Schmeil, p. 34. figs 1—8.
1903. _ — — Thompson & Scott, p.244. | 1911. _- minor Giesbr. Wolfenden, p. 244.
1904. — - — Wolfenden, p. 111,

Description. £9. Size of specimen from St. 88 was 4°65.mm.; anterior division 3°68 mm.; uro-
some o'97 mm. Giesbrecht’s specimens measured 32, Farran’s 42, and A. Scott’s 3'5--4'5 mm.

COPEPODA 133

The strong and short rostrum (text-fig. 35 a) is directed forwards and downwards. The lateral
corner of the thorax is triangularly pointed on the left side and rounded on the right (text-figs 35 b—c).
The first abdominal somite is as described by Giesbrecht asymmetric, and possesses on the right
side, dorsally, a strong curved spine; on the left side at the posterior margin we find in most specimens
two vertical rows of from 4—1r10 teeth, placed the one above the other; on the right side a more regular
row of teeth is observed. The structure of the vulva seems to be rather simple (fig. 3a). Only in a

single specimen was there found on the left side of the third abdominal somite near the hinder margin

=

}

hind the transverse chitinous list, which is placed Text-fig. 35. Undeuchete minor Giesbr.

a. £9. Head X 33. b—c. f9. Left and right lateral corner
X 33. d. fo. Head X 39. e. fo. Abdomen X 39. f. fo.
a low hairy elevation is found; this is separated by Pes V. Risin X 59. g. yo (St. V) PesVin ant. view X 59.

a structure somewhat like the hairy cumulus, which
was figured (Taf. 37 fig. 55) by Giesbrecht. In

a single specimen a moderately long slender seta
was observed in Re I of the aztennac. In the lobe
IV of the second basipodite in the maxzllipeds no ;
sensory process was observed. The frst pair of
legs has no Se Re I, but Se Re II extends almost
to the base of Se Re III; the articulation between
Re I and II is fairly well marked except anteriorly
and medially. The lateral margin of Re II has a
glandular pore near the base of Se Re II, and that G
of Re III has one placed near base. The Se Ril
has a well developed accessory tooth in pes II, and d
a somewhat smaller one in pes IV; the inner margin
of the second basipodite is smooth in the fourth
pair of legs. Glandular pores were found in Re II
and in Re III at the base of Se 3, and in pes III
—IV as well in Rel.
The lateral outline (text-fig. 35a) of the /a-

brum is somewhat similar to that of Zuchete. Be- f

somewhat behind the insertion of the antennulae,

a depression from the well raised labrum proper.
On the said elevation a median group of long setae and on each side lateral ones of short setae are
observed. Along the posterior margin of the labrum long setae are placed in the middle, and shorter
spine-shaped ones laterally. The oral surface of the labrum is very similar to that of U. major (cf. fig. 2a),
but the number of setae in the first group is somewhat larger. The /amina labialis and the two series
of setae in front of it are in the main’ like fig. 2b, but the number of setae is larger; the arrange-
ment of hairs on the labial lobes and. behind is similar to fig. r¢.

fg. Size of specimen from Thor St. 90 was 3°93 mm.; anterior division 289; urosome 1°04 mm.
A. Scott’s specimens measured 3'2—3°6 mm.

The rostrum is straight and directed directly downwards; the head is raised but has no frontal

134 COPEPODA

keel. The body is rather slender and in dorsal view somewhat attenuated towards the front; the lateral
corners are rounded (text-figs 35 d—e). The addomen, which is at least one third as long as the an-
terior division, is long and slender. The genital opening is placed on the left side; the fifth somite is
scarcely visible from above; the caudal rami are short (only half as long as the fourth somite, rounded
and about as long as wide). The terminal setae are distinctly longer than the abdomen, and the Si is
one fourth as long as St. 2.

The antennulae extend about to the end of the third abdominal somite; the segments 8~ 9 are
partly fused with 10, and 12 with 13, but the segments 20 and 21 are well separated on both sides.
The measurements are very like those of the female; the appendages are practically like those of
Aetidius. The antennae are scarcely different from those of the female; the manducatory part of the
mandibulae is well developed and rounded, but soft-skinned, without any teeth, while the terminal setae
of the palps are more pewerful than in the female. The maxillulae have no setae in Li 1—2, but 3
in Li 3; the number of setae in the third basipodite and the Ri is as in the females, but they are more
slender. The Re has 10 powerful setae, which were all of equal length. The maxz//ae form an angle-
shaped soft-skinned organ, in which distally soft-skinned, irregular twisted appendages are found. In
the second basipodite of the maxillipeds two setae are found in the fourth lobe; the third basipodite
is enlarged basally, and attenuated towards the end; the setae of the endopodite are fewer in number
and less powerful.

The frst pair of legs has a well developed articulation between Re I—II, and the Se Re II is
short and strong, and far from reaching the middle of following segment; in other respects the natatory
legs are scarcely different from those in the female.

The right leg of the fifth parr (fig. 3b) has a short second basal segment, which is fused with
the corresponding one of the left side, and is strongly produced outwards, and a much longer and wider
third basal segment. The right endopodite (fig. 3 e), which extends to the end of Re IwII, is rather
elongated, distally slightly curved and, as shown in fig., somewhat hollowed; its anterior surface is
distinctly striated, and marginally we observe a basal tooth, followed by a distinct striated keel, which
is most elevated in the middle (figs 3c and e). The Re IwII of right leg, which are almost completely
fused (figs 3 c—d), have in the proximal part the inner surface striated, and the outer one mounted with
a few rounded rudimentary teeth, followed by an elongated lamina, and lastly a distinct tooth; the distal
portion (Re II) is somewhat attenuated, and has medially a somewhat contorted, irregular lamella; the R III,
which is comparatively short, has its inner surface somewhat excavated, and has the posterior inner margin
lamellous, The /eft deg (fig. 3b) has a short second basal segment, but a long and wide third one; the
left endopodite (text-fig. 35 f) is long and slender, reaches distinctly beyond the middle of Re (not seen
in fig. 3b), is widest at the base and is distally enlarged to a rounded lamella (text-fig. 35 f). The left
exopodite has a fairly short, somewhat curved Re I, a rather short Re II which terminally possesses
a strong spine bearing a basal accessory tooth (fig. 3 f), and a moderately long Re III, which possesses
a long terminal seta and a group of fairly long setae anteriorly and interiorly; the last segment is
laterally connected with the Re II by a real articulation, but medially by a wide, soft membrane of a
somewhat complicated structure.

COPEPODA 135

yg (St. V). Size of specimen from Thor St. 88 was 3:16 mm.; anterior division 2°51 mm.; urosome
o65 mm.

In the shape of the body etc. it is scarcely different from the adult female, but the lateral
corner of the thorax is more pointed, showing, however, a similar difference between a more pointed
left and a more rounded right corner. In one of five females a strong spine, similar to that of the adult,
directed upwards and slightly backwards was found dorsally near the posterior margin of the first ab-
dominal somite on the right side; in two other specimens the spine was represented by a single tooth, or
a few only; along the posterior margin of the second abdominal somite no short teeth were found. The
appendages are in the main like those of the adult females; the Re of the maxillulae possess as usual
only 10 setae, of which the median are the shortest; the Se of Re II pesI is shorter than in the adult
female, but longer than in the adult male, reaching somewhat beyond the middle of the following seg-
ment. The male is always easily distinguished from the female by the presence of a rather short and
clumsy f/th pair of legs, of which the left is the longer (text-fig. 35 ¢). :

Occurrence. The Ingolf Expedition has taken 2 females, of which one with spermatophore.

12/, 1896 St. 47 61°32 L. N. 13°40 L. W. V*! 100o—o fathoms. Temp. at surf. 106° C.

The Thor has gathered it at the following stations:

/, 1904 St. 183 61°34 L. N. 18°43 L.W. Yt. 1800 M. Wire 7 f9.

15/6. 1905 St.82 51°00 L. N. 11°43 L.W. Yt. 1200 M. Wire 3 f9, rfid.

29/s 1905 St. 164 61°20 L. N. 11°00 L. W. Yt. 300 M. Wire 1 f9.

8/6 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 11 f9 (one with 4 sp.).

20/6 1905 St.88 48°09 L.N. 8°30 L. W. Yt. 300 M. Wire go f? (35 with sp.), 2 id, 4 y?(V), 6 yo (V).
16 1905 St.9o0 47°47 L.N. 8°00 L. W. Yt. 300 M. Wire 125 £2 (85 with sp), 36fd, 3 y?, 5yd&.

Distribution. This species seems to have a world-wide distribution. It has been recorded from
the warm area of the Feroe-Shetland channel, from the west coast of Ireland as far north as 54° L.N.
“at depths of from 400 to 1100 fathoms”. It has been taken by the Monaco Expedition and by the
Gauss Expedition in the Mid- and South Atlantic as far south as 35° L.S. By the Siboga Expedition
it was found rather common in the Malay Archipelago; it was recorded by Giesbrecht from the
Pacific (6°20 L. N. 166—173 L. E.) and by Esterly from the Bay of California.

Remarks. In spite of a few minor differences I am fairly convinced that this species is identical
with that described by Giesbrecht. Though Scott’s fig. 8 Pl. XXII is wanting in details I think his
male is identical with that described here. Scott is possibly right in identifying Lubbock’s Undina
plumosa with this male, in spite of minor differences, especially in the structure of the right fifth foot,
which may, however, be due to a mistake; as Lubbock’s description is rather incomplete, I do not at
present accept the name U. plumosa. —

I think Scott is right in referring the female of Brady’s Euchete pulchra Lubb. to U. minor,
As far as I understand Scott, he refers Brady’s Euchete pulchra? and his £. australis 2 to the same
species, but when we compare Brady’s fig. 5 Pl. 2r and fig. 6 Pl. 14, it is easily realised that the two

animals are probably not identical, especially on account of the different shape of the genital somite. I

136 _ ‘COPEPODA

think the similarity with the other species of this genus, as pointed out by Giesbrecht as far as U.
major is concerned, is better marked, but it may just as well be a species not yet rediscovered, A. Scott
also regards the male of Brady’s Z. australis as identical with this species, and so does Sats; Brady’s
figs 8—g Pl. XXI show that it belongs to an Undeuchete, but is far too incomplete for the drawing of

further conclusions.

38. Undeuchete major Giesbr.
(Pl. V figs 2a—d; text-fig. 36).

1883?9. Eucheeta australis n.sp. Brady, p. 65, pl. XXI figs 5—11. | 1905. Scolecithrix cristata Giesbr. Farran, p. 35.

1888. Undeuchete major n. sp. Giesbrecht, p. 335. 1903. 9. _ “= — Esterly, pp. 147—148 fig. 16.

1892. — — Giesbr. Giesbrecht, p. 227, pl. 37. 1905. Chirudina angulata n.sp. G. O. Sars, p. 13.

1895. — _ _ _ p- 251. 1906, Undeuchete major Giesbr. Pearson, p. 15.

1898. — — — Giesbrecht & Schmeil, p.34. | 1907. — — — G.O.Sars, p. 3.

1900. -— _— — J.C Thompson, p. 278. 1908, - -- — Farran, p. 37.

1903 CG. Scolecithrix cristata Giesbr, J.C. Thompson, p. 21, pl. | 1908. 9. — _ — vy. Breemen, p. 43, fig. 49.
III figs 1—5. 1909. _ _ — A.Scott, pp. 61—62.

1904. — — — Wolfenden, p. 111. IgII. — -- — Wolfenden, p. 243.

1904. -- _ _ Cleve, p. 198.

Description. f£9. Size of female from ‘Thor St. go: 4°92 mm.; anterior division 3°91; urosome
104 mm. Giesbrecht’s specimens measured 4°5 mm. and Scott’s 48—64 mm.

The lateral corners of the thorax are asymmetrical in a similar way as in Und. minor; on the
left side it is triangularly pointed, more so than shown in Giesbrecht’s fig. 5a (Taf. 37); on the right
side it is more rounded, and bears a small conical process just in front of the end. The oblique hinder
margin has two groups of short spines.

The antennulae are like Giesbrecht’s description, but the measurements are somewhat dif-
ferent; the segment 17, f. inst. is scarcely, not distinctly, twice as long as the segment 12. The mouth-
appendages are scarcely different from Giesbrecht’s description. The matatory legs differ in a few
minor points from those of U. minor; the Se Re II in the first pair of legs extends somewhat beyond
the middle of Re III, but does not reach the end of it; the accessory tooth of Se RiI of pes I, which
was just indicated in the preceding species, is fairly distinct. The inner margin of the second basi-
podite of the fourth pair of legs is not quite smooth, but finely undulated, and the posterior surface
possesses near margin just above the insertion of Si from one to four closely placed short spines.

The /adrum is in lateral view like that of the preceding species. The oral surface of the
labrum (fig. 2a) shows a structure similar to that of Chiridina Streets? (fig. 4b), though less complicated;
the first group consists of about 25 short hairs, placed in an oblique row; the second to the fifth
groups possess a regular median row and a more or less irregular lateral portion. The transverse rows
of setae are very regular. The chitinous framework is well developed. The /amina labialis, as seen
in fig. 2b, is distinctly divided into three divisions, and is distinctly striated; in front of the lamina a
median slightly curved series of about 20 setae is found, and a lateral one of numerous setae, of which
the posterior ones are rather delicate. Behind the lamina 4 spinous areas are found on each side, of
which the first one is almost obsolete. The arrangement of the setae upon and behind the labial lobes

differs from that of following species by the comparatively few and long setae in the second series.

COPEPODA 137

£3. Size of specimen from Thor St. 90 4°92 mm.; anterior division 3°59 mm.; urosome 1°33.
The head is, as in the female, mounted with a distinct frontal keel; the body is more slender
than that of the female and even more so than that of the preceding species. The lateral corners are
regularly rounded. The St. 2 of the caudal ramus is longer than the urosome. The anztennulac
extend about to the middle of the abdomen. The mouth-limbs are like those of the preceding
species, but soft-skinned, short rounded appendages were observed in the Li I—II of the max-
illulae, and the appendages of the maxillae are better developed. The ses 7 shows the same |
difference as in U. minor, and the second basipodite of the fourth pair of legs is smooth.

The f/th pair of legs differs from that of U. minor by a few features only; the fext-tig. 36.
Undeuchate
mayor Giesbr.
with a distinct process in the middle, in shape different from that of the preceding species; fg. Pes V sin.
X 59-

inner margin of the Ri dext. (fig. 2c) has basally a distinct tooth, followed by a lamina

the outer margin of Re I dext. has a rather low keel, but no distinct teeth. The Re III
sin. (fig. 2d) differs by shorter terminal seta and by the different arrangement of the setae. The left
endopodite is more slender (text-fig. 36).

YQ (St. V). Size of female from Thor St. 82 4°95mm.; anterior division 3:91 mm.; urosome 1'04 mm.

The shape of body with the frontal keel is scarcely different from that of the adult female.

The Se Re II in the first pair of legs is not shorter than in the female; the inner margin of
the second basipodite in the fourth pair of legs is completely smooth.

Occurrence. The S/S Thor has gathered this species at three stations only:

15/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 1 £9 (with sperm.), 2 y? (V).
20/6 1905 St. 88 48°09 L. N. 8°30 L. W. Yt. 300 M. Wire 55 f2 (13 with sp.).
21/6 1905 St. 90 47°47 L. N. 8°00 L. W. Yt. 300 M. Wire 25 £9 (5 with sp.), 5f¢.

Distribution. This species was recorded by Farran “on every station of from 350 to 1000
fathoms and in 16 out of 34 gatherings, generally in moderate numbers” on the west coast of Ireland
as far north as 54° L. N. It has been met with during the Prince of Monaco’s cruises in the East
Atlantic and was recorded as rather numerous at several stations in the South Atlantic even south
of Africa at about 40° L. S. 35° L. E. by the Gauss Expedition.

It has been recorded by Esterly from the Gulf of California, by Giesbrecht from the
Pacific (L. N. 20 L. E. 173) and by Scott from the Malay Archipelago.

Remarks. In spite of the few differences enumerated above, I do not doubt that my Atlantic
specimens are identical with Giesbrecht’s from the Pacific.

A. Scott is certainly right in determining the male referred by Esterly to this species as a
species of Zuchete, as well as in regarding the male of Thompson’s Scolecithrix cristata as belonging
to this species.

39. Undeuchzte superba n. sp.
(Pl. IV figs 6a—b; Pl. V figs 1a—c; text-figs 37 a—f.)

Description. f£9. Size of specimen from Thor St. 183 was 642 mm.; anterior division 5:11 mm.;
urosome I°3I mm.

A rounded, rather low, but fairly prominent frontal keel is found; the undivided rostrum is short,
but strong (text-fig. 37a). The head and the first tergite are fairly well separated; the fourth and fifth

The Ingolf-Expedition. III. 4. 18

I 38 COPEPODA

thoracic tergites are completely fused. The right lateral corner of the thorax (Pl. V fig. 1a) is fairly
regularly rounded and somewhat shorter than the left one, which is triangularly produced and some-
times shows trace of bifurcation (fig. 1 b).

The abdomen is about one fourth of the anterior division; the genital somite is a little deeper
than wide and long; on the right side it has a strong, fairly long spine, directed upwards and back-
wards (fig. 1a; text-fig. 37b); in the middle it is strongly produced, and has on the right side of the
vulva a strong spine directed backwards. Along the hinder margin of the third somite ventrally short
triangular teeth are found; they seem to be wanting in the other somites. The caudal rami are distinctly
wider than long; the terminal setae are at least as long as the abdomen, and the Si is one third as
long as St. 2.

The antennulae extend almost to the end of the fourth abdominal somite. The Re of the
antennae is 1-7 as long as the Ri. The maxillulae have in Le the S 1—3 of moderate length, the S 4
somewhat longer and the S 5—9 much longer, but of almost equal length; the Re has, as in the two
preceding species, the median setae distinctly shorter than the others, but not in so marked a degree.
The maxillipeds, in which the comparative length between Basp. 1 © 2, Basp. 3 and Ri is as 30—52—13,
have the setae of Ri even better developed than in the preceding species, so far resembling the
corresponding limbs of Euchete. The mandibulae and maxillae are scarcely different from those of
U. mayor.

The frst pair of legs has the articulation between Re I and II almost obsolete; the Se Re II
extends distinctly beyond the middle of Re III, but scarcely to the end of it. The second pair of legs
has a fairly well developed accessory tooth in Se Ri I (text-fig. 37 c),and the St. has 45—so serrations.
The Se of Ri I in the fourth pair of legs has a distinct pointed accessory tooth, even better developed
than the more rounded one in pes III; the inner margin of Basp. II is somewhat undulated, and
has on the posterior surface, in a similar position as in the preceding species, five short spines (text-
fig. 37d). The glandular pores are as in the other species.

The anterior coecal sac seems to be wanting. The lateral outline of the /aévum is not quite
like that of the two preceding species; the anterior elevation, which on each side possesses about
two groups of long slender hairs, forms an obtuse angle with the labrum proper; this is on each side
in front beset with a small number (about 50) of short hairs.

The oral surface of the /abrum is like that of U. major (fig. 2b Pl. V), but shows similarity to
that of Ch. Streetsii by a larger number of setae; the lateral group of setae, f inst. consists of 30—40
short spines, and the first group of the longitudinal series has two instead of a single row. The d-
mina labialis and the area in front of it are scarcely different from those of the preceding species. The
series of hairs behind and upon the labial lobes is rather characteristic as shown in fig. re (Pl. V). The
series I consists of a single oblique row laterally placed; the series II is represented by a large median
and posterior group of short hairs; the series III seems to be represented by a fairly big group in the
middle, almost fused with the corresponding portion of the opposite side, by a more lateral group partly
fused with the fourth group and by two oblique rows on the labial lobe; the series IV consists of a
median group fused with the third and fifth series, and of a rather short row on the labial lobe; the
fifth series consists of a median group and a lateral row.

a re “4

COPEPODA 139

£3. Size of specimen from Thor St. 183 was 5°35 mm.; anterior 4:08 mm.; urosome 1:27.

The rostrum and the frontal keel are scarcely different from those of the adult female. The
body is more slender, and the lateral corners are rounded and symmetrical. The abdomen is scarcely
different from that of the two preceding species. The aztennulae extend about to the end of the third
abdominal somite, and are also in other respects similar to those of the preceding species. The antennae
are practically like those of the female, but in the ReI a small conical process was observed medially,
apparently bearing a delicate seta. The manducatory portion of the mandibulae possesses posteriorly
one or two rudimentary teeth. The maxzlludae have short soft appendages in Li 1—2; the Le has 2
short and 6 long setae, and the 10 setae of the Re are as usual in the male not shortest in the
middle; the Li 3 has 3 setae, and the Basp. as well as Ri have a similar number of setae as in the fe-
male, but they are softer. The maxiliae and maxillipeds are scarcely different from those of the preceding

species. The first pair of legs has as usual a well developed

articulation between Re I—II, and the Se Re II is compara-
tively short; the pes II—IV are scarcely different from those
of the females.

The right leg of the fifth pair has the basal seg-

ments like those of the preceding species (cf. fig. 3b Pl. V).
The right endopodite is in general shape very much like
that of U. minor (figs ga—b PI. IV, cf. fig. 3e Pl. V); it is
terminally somewhat curved and has here lamellar margins,
turned over to establish a gutter-shaped excavation facing
b
d

forwards and outwards. Outwards and backwards a well

developed conical tooth is found near the base, and beyond
Text-fig. 37. Undeuchete superba n. sp.

this, removed one third of the length of the segment from a. £9. Head Xc.30. b. £9. Abdomen X 9.

ce. £9. Pes If RiI sin in ant. view 150. d. f9.
Pes IV basipod. II in post. view xX I50. e& yd
really forms the middle of the marginal, here scarcely (St. V). Pes V ant. view X 33. Yo (St. IV). Pes V
ant. view X 59.

the base, another striated tooth or elevation is found, which

indicated, keel present in the two other species; the anterior
surface of the endopodite is distinctly striated. The first segment of the right exopodite (figs 6 a—b)
is basally and in front produced into a wing-like expansion bearing three serrations, which are followed
by a low keel and, somewhat more distally, a well developed tooth, where in the typical specimen a
soft-skinned parasite, divided into three globules as seen in figs, is fastened; the second segment, which
is almost completely fused with the first, has distinct marginal lamelli-form expansions; the third seg-
ment is elongated, somewhat attenuated and includes a gutter-shaped excavation facing inwards.

The basal segments of the /e/t /eg are in main features like those of the preceding species;
the left endopodite, which extends distinctly beyond the middle of Re I, is elongate and attenuated
with undulated margin; the first segment of the exopodite is less robust and somewhat shorter than
the third basipodite, and somewhat convex; the second segment is short, about 1°5 as long as the
strong curved tooth, which has a distinct accessory tooth; the third segment is similar to that of the
preceding species, but the terminal spine is distinctly articulated.

18*

140 COPEPODA

The elevation in front of the labrum is well developed but smooth. The /adrum is rudimentary
without distinct setae, and so is the area labialis; both are soft-skinned with ringed chitin. Laterally
we observe one to two groups of very short hairs.

xg (St. V). Size of female from St. 167 Thor 1905 was 4°77 mm.; anterior division 380 mm.;
urosome o'797 mm. A male from the same station measured 488 mm.

Shape of body, but for four abdominal somites and more triangularly pointed lateral corners of
the thorax, is like that of the adult female. The ReI of the antennae apparently bears a setigerous
process like that of the adult male; the other appendages do not show features of interest.

The only difference between the males and females is found in the presence of the fifth pair
of legs, which, as shown in text-fig. 37 e, has a rather characteristic structure.

¥e. (St. IV). Size of male from St. 183 was 3:28 mm.; anterior division 2°70 mm.; urosome 058
mm. Size of female from the same station 31 mm.

The frontal keel is lower, and the lateral corners of the thorax are less pointed. The mouth-
appendages do not show features of great interest. The Re II~III of the second pair of legs are
fused, have only 3 Se but the usual number of Si; a glandular pore is only found in Re III at the base
of Se 3; the fourth pair of legs has also a glandular pore in Re I, and has the inner margin of the second
basipodite smooth. The only difference between the male and female is found in the presence of a
fifth pair of legs with undivided Re and Ri as shown in text-fig. 37 £.

Occurrence. The S/S Thor has taken a few specimens of this species at several stations.

19/6 1904 St. 152 65°00 L. N. 28°10 L. W. 1 £2 (with sperm.), 1 fd, 1 yh (V).

21/6 1904 St.154 65°27 L. N. 27°10 L. W. 1f9 (with sperm.).

10/, 1904 St. 180 61°34 L. N. 19°03 L.W. Yt. 400 M. Wire 2 f2 (with sperm.).

t/, 1904 St. 285 62°49 L. N. 18°46 L. W. rig.

1t/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 11 £9, 2fd,1y? (V), 6yh (V), ry (IV),
25/, 1904 St. 104 62°47 L. N. 15°03 L. W. TT? 11g OM
2/, 1904 St. 286 61°49 L. N. 14°11 L. W. 2£9, 1 yd.

29/, 1905 St. 165 60°00 L. N. 10°35 L. W. r f9.

22/, 1904 St.99 61°15 L.N. 9°35 L. W. ; 1 f9.

Outside the Ingolf area the species has been taken

5/6 1905 St.82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 1 £9.
3t/g 1905 St. 167 57°46 L.N. 9°55 L.W. Yt. 1500 M. Wire 1 f9, 3 fo, 1 y? (V), 1 yd' (V).
8/6 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 6f9, rfl, 2 yo

Remarks. As this species was found not only in the Atlantic south of Iceland, but also in
Denmark Strait and in the Iceland-Feroe channel, while it was wanting in some of the more southern
stations in which the two other species were found, it is possibly a more northern form.

It belongs naturally to the same group as U. minor and major, though it is well distinguished
from both by combining the right lateral spine of the genital somite and the ventral spine on the

COPEPODA I4I

right side of the vulva, as well as by the frontal keel and by the teeth on the second basipodite of
the fourth pair of legs..

This species is even more related to two newly established species, but if the descriptions are
correct, it is scarcely identical with them.

From U. intermedia, which was described by A. Scott (1909 p. 63—64; Pl. 23 figs 1—8), it differs
by a distinctly raised forehead between the rostrum and the keel, by the different shape and direction
of the two characteristic spines of the genital somite, as well as by a few other characters. From Wo lf-
enden’s Mesundeuchete assymmetrica (1911 pp. 244—245; Taf. 29 figs 4—7; text-fig. 28) from the South
Atlantic, which it is very much like in dorsal view, it differs by the structure of the vulva, as the
right spine is wanting in Wolfenden’s species. To encompass these species he established a new genus
on account of the teeth of the posterior surface of the second basipodite of pes IV; as the presence
of such spines (cf. Aétidius Pl. II fig. 1c), even if they are often wanting, is a rather characteristic
feature in the Aefidiidac, and as such spines are found in U. major as well, the foundation is rather
too weak. When all the structural features of males as well as of females are taken into consideration,

it is quite evident that the five species go naturally together.

40. Chirudina Streetsii Giesbr.
- (PL V figs 4a—f; Pl. VIII figs. 5a—b; text-figs 38 a—k.)

1895. Chirudina Streetsii n. sp. Giesbrecht, pp. 249-250; taf.1 | 1906. Chirudina Streetsii Giesbr. Pearson, p. 16.

figs 5—1I0. 1906. — — — Esterly, p. 59, pls 9, 10, 12, 14.
1898. -- — Giesbr. Giesbrecht & Schmeil, p. 34. | 1908. — _ — Farran, p. 37.
1go2 nec, Euchirella carinata n. sp. Wolfenden, pp. 366—367. 1908. -- — vy. Bremen, p. 46.
1904? _ _ Wolf. Wolfenden, pp. 115—116. 1909. -- — — A. Scott, p. 43, pl. XII figs
1904. Chirudina Streetsii Giesbr. Cleve, p. 187. ? I—II.
1905. —_ — — .G.O. Sars, p. 4. 1913. — _ — Wolfenden, p. 241.

Description. {9. Size of specimen from Thor St. 72 was 5:22 mm.; anterior division 4:18; uro-
some 1:04 mm. Giesbrecht’s specimens measured 5:3 mm. Scott’s specimens measured 48—5:3 mm.

The frontal keel and rostrum are well developed, as seen in text-fig. 38a; dorsally there is trace
of articulation between the head and the first thoracic somite; the fourth and the fifth thoracic tergites
are completely fused, except dorsally, where trace of segmentation may be found. The lateral corners
vary very much in the different specimens; they are more or less rounded, but mounted with a pointed
process, which is sometimes almost wanting, especially on the right side (text-figs 38 b—e), but is some-
times well developed. The genital somite is in dorsal view slightly asymmetrical, as the right outline
is more regularly rounded than the left; the genital area (fig. 4 a), looked at from beneath, is very similar
to that of C. pustulifera, but observed from the side, a fairly prominent anterior protuberance and a
short, sometimes completely covered, posterior one are seen. é

The antennulae extend about to the base of the furcal branches; the segment 19, which is the
longest segment, is about rz as long as 20, which is again longer than 17, the latter being about
rz as long as 16; the segment 16 is rz as long as 2425. The exopodite of the antennae is 15
as long as the endopodite; the second segment of the endopodite has 7-+-7 setae; the first segment
of the exopodite, which is well defined and about one third as long as the second, has a weil devel-

142 COPEPODA

oped setigerous process inwards, and the second segment has a similar one at the base in addition to
ones sitting in the middle as well as terminally (text-fig. 38 f). The mandibulae and maxillulae do not
show any features which were not mentioned in Giesbrecht’s description. The maxzillae are very
much like fig. 5c of Ch. abyssalis. The third basipodite of the maxzllipeds, which is almost twice as
long as the Basp. 12 and distinctly three times as long as the Ri, has along the exterior margin almost
from base to tip on the
posterior surface a low
transparent lamella with
a distinct concavity in the
middle; the fourth lobe
of the second basipodite
is placed posteriorly, and
has a fairly long sensory
lobe surrounded by slen-
der hairs, in addition to
three setae (text-fig. 38 g);
anteriorly, and somewhat
removed from the tip, a ~
rounded protuberance is
found in the second basi-
podite, probably corre-
sponding to that of Z. cur-
ticauda, The first patr of
legs has the inner margin
of the last basipodite
slightly convex, as seen in
text-fig. 38h ; the Se of Ril
has no accessory tooth in

the second pair of legs, and
no trace of it in the third

Text-fig. 38. Chirudina Streetsit Giesbr. £9.
a. £9. Head X 30. b. £9. Abdomen x 18. c. f9. Lateral corner from the right side x 18.
d—e. f?. Left lateral corner x 18. f. £9. Antenna sin. Re x 57. g. £9. Maxillipes dext. and fourth pairs (text-fig,
in post. view X57. h. £9. PesI sin. 57. i. £9. PesIV sin. Xc¢.20. j. yQ (St. V). Left A Ss
lateral corner X 18. k. yo (St. V). Pes V in anterior view. 381i); the inner margin of

the second basipodite in

the fourth pair of legs is in most specimens completely smooth, but in some has one or two short
stiff hairs corresponding to Giesbrecht’s “sparlichen kurzen Spitzen”. The glandular pores are like
those of Undeuchete. The elevation in front of the dabrum is smooth and fairly well raised; along
the posterior margin the labrum proper has as usual a median row of long and slender hairs divided
into a right and a left part, and a lateral shorter one, of more spine-shaped setae. The oral surface of
the labrum (fig. 4b) is like that of Undeuchete, The first group of the longitudinal series is placed
obliquely, and consists of about ten fairly strong setae; the second group consists of two rather inde-

COPEPODA 143

pendent parallel rows; the third group as well as the fourth and fifth has the inner rows of setae
in each group fairly well separated, but has the more laterally placed hairs of each group rather irre-
gularly placed. Behind and laterally to the fifth group on each side a large number of very delicate hairs
are found. The lateral group in front consists of numerous delicate short hairs. The transverse series
around and behind the median circular spot Nr. 4 is shown in fig. qb.

The lamina labialis is minutely granular and, as seen in fig. 4, laterally prolonged backwards;
the lateral series in front consists, except posteriorly, of a single row; the medial series, in front of which
a minutely granular area is found, is fairly long.

The arrangement of the series of hairs behind and upon the labial lobes is the following (fig.
4d): the first series is almost longitudinal and consists of 10 hairs; the second series consists of a
group of about 10 hairs; the ¢hird series consists of two well separated transverse rows, well removed
from the longitudinal row upon the labial lobe; in front of the two mentioned transverse rows 2 others
are observed, which probably belong to the fourth sertes; this is well developed upon the lobe and
has proximally a large group of numerous hairs, partly belonging to the ///h series, which medially
has a transverse row. In at least one of the specimens several of the hairs are slightly clavate. Behind
the transverse line which separates the mandibular and maxillular somites, groups of hairs, as shown
in fig. 4d, are found.

A short but distinct frontal coecal sac is found.

fg. Size of specimen from Thor St. 88 was 380 mm.; anterior division 2°83 mm.; urosome
097. Scott’s specimen measured 4°1 mm.

The frontal keel and the rostrum are (as seen in Pl. VIII fig. 5 a), somewhat different from those
of the female. The body is rather slender and attenuated towards the front, but less so towards the
end; the lateral corners are rounded. The anterior division is 38 as long as the abdomen, which has the
genital opening on the left side and short triangular teeth along the hinder margin of the second to fourth
somites. The antfennuwlae extend scarcely to the middle of the abdomen; the segments 8~9 are almost
completely fused with 1o and 12 with 13, but the segments 20 and 21 are well separated on both sides.
The exopodite of the aztennae, which is 14 as long as the endopodite, has in the first. segment a
single process without setae, and in the second 2 basal processes and a single terminal one. The soft-
skinned manducatory part of the mandibulae has a single well developed tooth and a few rudimentary
ones, and the Ri2 has g Sa, but not, as in female, a Sp.

The maxillulae possess at least 6 soft sensory (?) appendages in Li1; the Li2 was wanting,
but in Li 3 at least 3, in Basp. 3 at least 3, and in Ri at least 11 setae were found. The Re has 10
well developed plumous setae in addition to a delicate interior one, and Le has 2 short, delicate, basal
setae in addition to 5 distal, long ones. The maxillae (Pl. VIII fig.5b) have 5 well developed lobes,
of which the fifth one bears a big twisted seta with enlarged base; the endopodite has at least 5 setae.
The maxillipes is more clumsy than that of the female, in shape ressembling that of the males of Und-
euchete; the third basipodite is 13 as long as the two first ones and 2°5 as long as Ri; the lob. IV of
the second basipodite has a long, slender seta and a rather short, curved, spine-like one in addition to
the usual conical one.

The first pair of legs differs from that of the female by the very short Se of ReI; the Se of

144 COPEPODA

Ril in the ¢hird pair of legs has a fairly distinct accessory tooth, but in other respects scarcely any
difference was observed between the natatory legs of the male and female.

The fifth pair of legs is in general structure most like that of Undeuchete minor (P\.V fig. 4 e),
to the description of which I partly refer. The right endopodite is about as long as the first segment
of the exopodite, enlarged distally and here gutter-shaped; on the posterior surface near the base a
short tooth was observed, and along the outer margin a short and low lamina. The first and second
segments of the right exopodite are completely fused, and have in the middle an obtuse angle open
outwards; the outer margin has proximally two large teeth and a smaller one, and the posterior surface
has, near the end, one or two raised keels; the third segment of the exopodite is gutter-shaped, like that
of Undeuchete s.s. but has a terminal, well articulated seta, two thirds as long as the segment.

The third basipodite of the /e/t Jeg has inwards near base a blunt tooth; the exdopodite is
slender, projects beyond the end of the first segment of the exopodite, and it distally somewhat hol-
lowed; the second segment of the exopodite is rather short, has the inner surface distinctly hollowed,
and has inwards near the end a strong, rather short spine with a blunt accessory tooth as well as a
rounded process; the third segment of the left leg (fig. 4 f) is similar to that of Undeuchete, but is less
slender, and possesses a short bristle in addition to the terminal setae, which are distinctly half as long
as the segment.

¥¢ (St. V). Size of female from Thor St. 88 was 4:0 mm.; anterior division 315 m1m.; urosome
o85 mm. A male measured 4°02 mm.

The shape of the body is in the main like that of the adult male, but the frontal crest is some-
what lower, and the lateral corners are triangularly pointed, and scarcely different on the two sides;
the limitation, between the head and the first tergite as well as between the fourth and fifth ones, is
fairly distinct (text-fig. 38j). The first abdominal somite is better produced in the male than in the
female. The appendages show the usual differences from those of the adult female; the inner margin
of the second basipodite is smooth in both sexes, The “th pair of legs is, as seen in text-fig. 38 k,
fairly well developed.

Occurrence, The S/S Thor has in the Atlantic south of Iceland gathered this species at four

stations viz:

ly 1904 St. 285 62°49 L. N. 18°46 L. W. 2£9, ryd& (V).
/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 f9.
24/, 1904 St. 180 62°47 L. N. 15°03 L. W. Yt. 500 M. Wire 1 f9, 1 y? (V).
28/g 1905 St. 163 63°36 L. N. 12°05 L.W. Yt. 300 M. Wire 1 £9.

Farther south the species was in.one of five samples taken in big numbers.

15/, 1905 St.82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire 1ri¢t.
3t/gs 1905 St. 167 57°46 L. N. 9°55 L.W. Yt. 1500 M. Wire 5 f9.
8/6 1905 St-72 57°52 L. N. 9°53 L. W. Yt. r500 M. Wire 5 f9.
21/6 1905 St.90 47°47 L.N. 8°00 L.W. Yt. 300 M. Wire 5 f9. :
20/6: 1905 St. 88 48°09 L. N. 8°30 L. W. Yt. 300 M. Wire 137 £9, 7 £4, 27 yP (V), 62 ys (V).

a a eee ee eee

7
7

COPEPODA 145

Distribution. According to Farran “this species is of frequent occurrence in the N. E. Atlantic,
having been taken on every station at depths of from 300 to tooo fathoms”. It has been recorded
from the Feeroe channel, from the Mid Atlantic and from the South Atlantic as far south as 35° L. S.
It has been recorded from the Gulf of California, from the Pacific 35° L. N. 125° L. W. as well as from
the Malay Archipelago. |

Remarks. In spite of the small differences enumerated between my specimens and Giesbrecht’s
description I think the Atlantic and the Pacific forms belong to the same species. Different authors, f.
inst. Pearson and A. Scott, have identified Wolfenden’s uch. carinata with this species; they are
certainly wrong as far as the young male described in 1902 is concerned; on account of the frontal crest
like that of & galeata, the rounded lateral corners of the thorax and the left endopodite of the fifth
pair of legs “like small stump” there is some reason to identify it with, f. inst, Luchirella intermedia
(cf. p. 127). The position of the adult female is somewhat uncertain; Wolfenden regards it (p. 236) asa
true Euchirella in spite of the missing spines of the second basipodite of the fourth pair of legs. It
is with some reluctance that I have referred the described male to this species; at present it is impos-
sible to tell its certain position. The descriptions of Esterly and Scott are too short for a certain

identification.

41. Chirudina pustulifera G. O. Sars.
(Pl. V figs 6a—d; text-fig. 39.)

1905. Undeuchzete pustulifera n. sp. G. O. Sars, p. 14.
1908. Euchirella Wolfendenii n. sp. Farran, pp. 38—39; pl. II figs 18—19; pl. IV fig. 3.
1908. Undeucheete pustulifera G. O. Sars. v. Bremen, p. 44.

Description. Size of female from Thor St. 183 was 69 mm.; anterior division 5°7 mm.; urosome
12mm. Sars’ specimens measured 69 and Farran’s 7:2 mm.

The head has no frontal crest, but a strong, slightly curved rostrum (text-fig. 39). The fifth
somite is well limited in front, and the lateral corners are rounded (figs 6a—b). The genital somite
has a very characteristic shape (figs. 6a—b); on the left a low protuberance is found,

and on the right side a very prominent one, consisting of a basal larger portion

and a terminal regularly rounded part. The genital somite, seen from the side, has
a strong, rounded, rather prominent protuberance in front, and a lower one in PRE
the middle as well as behind; observed from below the genital area (fig. 6c) is like Téxt-ig. 39.| Chirudina
that of Ch. Streetsii. The abdomen is almost everywhere hairy, but the setae are re A al
longest and best developed dorsally along the hinder margin of somites II—IV.

Dorsally in the genital somite as well as ventrally in the third and fourth ones tufts of shorter and
longer hairs are observed. The caudal rami are about as long as wide, and the Si is scarcely half as
long as the St. which is about as long as the abdomen.

The antennulae extend to the end of the abdomen. The antennae are scarcely different from
Farran’s fig. 18 Pl. XI, except by the presence of a fairly long terminal seta in Re 2; the Re is about
17 as long as Ri. The mandibulae are scarcely different from those of C. adyssalis n. sp. (ch fig. 5 b);
the third basipodite is not smooth as indicated by. Farran, but has 3 setae. The maxillulae have 5

powerful setae in Li 2, have 4 + a conical process in Li 3, and 5 in the Basp. 3; the Ri I—III pos-
The Ingolf-Expedition. III. 4. 19

146 COPEPODA

sess 4-++5-+7 setae as in Ch, Streetst, ‘The exopodite has 11 setae, of which the median ones are
comparatively short, but not in so marked a degree as in Undeuchete, The Le has 9 setae (according
to Farran 8 only), of which the third and the ninth are somewhat shorter than the Set. 4—8, and
the first and second are much shorter. The maxillae are very much like those of Ch. abyssalis, cf. fig. 5¢,
and have the hairs on the posterior surface of the four lobes arranged in a similar way. The maxilli-
peds are very similar to those of Ch. Streetsi, but have no lamina along the outer margin of the
second basipodite, nor the anterior process of the second basipodite; the third basipodite is 1°5 as long
as the first and second, and 38 as long as the endopodite.

The frst pair of legs has the articulation between ReI and II represented by a fairly distinct
chitinous line, which is almost wanting posteriorly; the Se Re I extends beyond the end of Re II,
and the Se Re II extends just to the end of Re III. The second pair of legs has indication of
articular membrane between the Ri I—II, but has no accessory tooth at the base of the blunt Se Ri I;
the terminal spine has 70 serrations. The Se of Ril is pointed, but is without accessory teeth in the
two last pair of legs; the second basipodite of the fourth foot bears on the hinder surface of a process
projecting from the inner margin a transverse row of 8—11 strong, fairly long spines, of which the
inner are somewhat more slender.

The lateral outline of the /adrum is like that of Ch, Streets, with well raised, smooth, anterior
elevation, and so is the oral surface of the /abrum (fig. 6d); the only difference of importance is found
in the much longer first group, the almost wanting lateral row in the second group, and the much
better developed transverse row of short hairs in front of the transverse chitinous bar. The /amina labialis
and the area in front of it are scarcely different from those of Ch. Streetsi, while the arrangement of
hairs upon and behind the labial lobes is like that of Ch. abyssalis (fig. 5); a tuft of about 20 long
slender setae is found on the lateral surface of the labial lobe, just as in Ch. notacantha.

Occurrence. The S/S Thor has gathered this species at two stations.

11/, 1904 St. 183 61°30 L. N. 17°08 I. W. Yt. 1800 M. Wire 17 £9 (5 with sp.).
to/, 1904 St. 180 61°34 L. N. 19°03 L. W. Yt. 4oo M. Wire 1 £9 (with sp.).

Distribution. This species has been recorded from two stations between 700 and 1000 fathoms
off the west coast of Ireland; the Monaco Expedition has gathered it at three stations.

Remarks. The only difference found between my specimens and Sars’ description, which is
rather insufficient, is found in the comparatively shorter “antennes antérieurs dépassant la longueur
de la division antérieure du corps”. The Basp. II of pes IV has 6 for 11 spines. The unimportant dif-
ferences from Farran’s description are enumerated in the description. Farran has referred the species
to Euchirella, probably on account of the well developed spines in the second basipodite of the fourth
pair of legs, but it differs in a number of more important characters, viz: the structure of the oral
surface of the labrum, the wanting glandular pore of the base of Se 1 Re III pes II—IV, the compara-
tively long Ri of the antennae, the position of the spines on posterior surface of lobes I—IV of maxillae,
and the arrangement of the setae of the maxillulae. In all these characters it agrees with Chirudina as
well as, though in a less degree, with Undeuchete. It agrees with Undeucheie in the comparatively
short median setae of the Re of the maxillulae, but with CAivuwdina in the number of setae in Li 2 and

. is laterally not produced, and has evenly

COPEPODA 147

Ri of the maxillulae and the presence of a Se ReI pes I. The two genera are very nearly related,
but as the five species of Undeuchete form a very natural group I prefer to refer this species to
Chirudina,

42. Chirudina abyssalis n. sp.
(Pl. V figs 5a—f; text-figs 40 a—c).
Description. £9. Size of specimen from Thor St. 183 was 54 mm.; anterior division 4:3 mm.;
urosome I‘I mm.
The head is gradually rounded in front, without any crest; the rostrum is rather short, but
strong, directed downwards and slightly backwards (text-fig. 40a). The cephalothorax, which is moder-
ately slender and slightly attenuated towards the front part as well as towards the end, is about 2°5

as long as wide; the first thoracic tergite is, at least dorsally, well separated from the head; the fifth
somite, which is well separated in front,

rounded corners (fig. 5a). The anterior
division is about four times as long as the
abdomen.

The genital somite, which is a
little wider than deep and as deep as long,
is in dorsal outline almost symmetrical;

the ventral surface is anteriorly rather

suddenly produced and posteriorly gradu-
ally sloping; the genital area is in ventral

Text-fig. 40. Chirudina abyssalis n. sp.

view seen to be somewhat different from a, £9. Head X18, b. PesI X 33. c. Maxillipes sin. Basp. III in post.
view X 87.

that of the preceding species. The genital
somite possesses, dorsally, along hinder margin, short hairs, and ventrally tufts of longer hairs; the fol-
lowing somites are more and less hairy, the hairs being longest dorsally and ventrally. The caudal
rami are about as long as wide; the terminal setae are distinctly shorter than the abdomen and about
three times as long as the Si.

The antennulae extend to the end of the caudal rami; the measurements are very like those
of the preceding species. The exopodite of the antennae is 16 as long as the endopodite; the second
segment of the endopodite has 8 setae in Li and 7 in Le; the first segment of the exopodite, which
is one third as long as the second, has inside a short protuberance with a short hair; the second seg-
ment has only a terminal seta. The mandibulae have, as shown in fig. 5b, a rather characteristic shape,
and the maxillulae are completely like those of Ch. pustulifera, The maxillae (fig. 5c) are only
slightly produced basally, and have the spinous areas on the hinder surface of the four proximal lobes
distinctly different from those of most species of Zuchirella (cf. fig. 9d); in the first lobe a smooth area
is found surrounded by spines. The maxillipeds are scarcely different from those of the preceding species;
beyond the Si 3 in the third basipodite a longitudinal row of longer and shorter teeth is found (text-

fig. 4oc); similar teeth were found in Ch, pustulifera, but not in Ch, Streetsti.
19*

148 COPEPODA

The frst patr of legs (text-fig. 40 b) has the articulation between Re I and II better developed
than in the preceding species, but is in other respects scarcely different; the terminal spine of the second
pair of legs has 90 teeth, and the second basipodite of the /ourth pair of legs has 11 knife-shaped
spines (fig. 5 d).

The outline of the /edrwm is, as seen in text-fig. 4oa, somewhat different from that of Ch. Streetszz;
the oral surface of the labrum differs in the same way as that of Ch. pustulifera from that of Ch. Streetsiz.
The lamina labialis is smooth, and the area in front of it is, as shown in fig..5e, somewhat different
from that of Ch. Streetsiz, and so is the arrangement of hairs upon and behind the labial lobes (fig.
54), the main difference being that a large group of delicate hairs is found where the series III and
IV start at the base of labial lobes, not where series IV and V start. In front of the oesophagus a
long coecal sac is found.

Occurrence. Of this species the S/S Thor has only taken 4 adult females '/, 1904 St. 183 61°30
L. N. 17°08 L. W. Yt. 1800 M. Wire. tT

Remarks. ‘This species is very nearly related to Ch. pustulifera, and ought, accordingly, to be .
referred to the same genus. It shows some similarity to U. obtusa G. O. Sars (1905 p. 13; Farran 1908
p- 40), which has the antennules “dépassant 4 peine, en longueur, la division antérieure du corps”, as
well as to U. lobata G. O. Sars (1907, pp. 11—12), from which it seems to differ by lateral corners “assez

saillants en arriére et étroitement arrondis au bout”, by longer abdomen and antennulae.

43. Chirudina notacantha G. O. Sars. -
(Pl. V figs 7a—b; Pl. VI figs 1a—b; text-figs 41 a—k).

1905. Gaidius notacanthus n. sp. G. O. Sars, pp. 9—I0. 1909. Nec. Gaidius notacanthus G. O. Sars. A. Scott, p. 52, pl.
1908, _ G. O, Sars. Farran, pp. 33—34, pl. XXI figs 24—32. .
: III fig. 7.

Description. a (St. V). Size of a young male 5°72 mm.; anterior division 4°7 mm.; urosome
102 mm. Young females measured from 4°31—5'54 mm. Sars’ specimen measured c. 5 mm.

The lateral outline of the head is gradually sloping towards the strong undivided rostrum,
which is directed downwards and slightly backwards (text-fig. 41 g). The cephalosome, which in the
middle is scarcely half as broad as it is long, is attenuated towards the front as well as towards the
end. The head is well separated from the first thoracic tergite, and the fifth one is well marked out
in front (text-fig. 41 i); the latter somite is, near dorsal margin, produced into a strong triangularly
pointed spine, which scarcely attains the end of the first abdominal somite. The abdomen, which is
scarcely one fourth as long as the anterior division, has four somites, the comparative length of which
was 22, 29, 21, 17 and 15 (furcal branch); the furcal branch is distinctly wider than long. Along the
hinder margins densely placed hairs are found; the terminal setae ate distinctly shorter than the ab-
domen (text-fig. 41 j).

The antennulae extend almost to the middle of the abdomen; in measurement they are very
much like those of Ch. Streetsit. The exopodite of the antennae is almost 18 as long as the endopo-
dite, which has 7 setae in Li and 6 in Le; the first segment of the exopodite has a short process
inside, bearing a delicate seta, only as long as the process itself, and the second has a terminal seta

COPEPODA 149

inside (cf. Ch. abyssalis), The maxillulae have in addition to the 4 Sp. on the posterior surface of Li 1
a short S 15; the Le 2 has 5 setae, the Li 3 has 4 setae and the Basp. III has 5 setae; the endopodite
has 3 setae in RiJI, 5 setae in Rill and 7 setae in RiIII. The exopodite has ro setae of about equal
length, and the Le has 2 short proximal setae and 7 long distal ones. ‘The maxillae are scarcely dif-
ferent from those of Ch. abyssalis cf. Pl. V fig. 5c, and the maxtllipeds have the third basipodite 33 as
long as the endopodite and
16 as long as the two basal
segments.

The frst pair of legs
is very much like that of CA”.
abyssalis; the. articular mem-
brane between Re I—II is com-
pletely wanting’ posteriorly
and only slightly developed |
anteriorly; the Se of Re I
distinctly extends beyond the
end of preceding segment,
and so does Se of Re II.
The articulation between Ri
I—II in the second pair of
legs is wanting posteriorly,
but is marked by an_ indi-
stinct line anteriorly, and the
Se of Ril is slightly marked
as seen in text-fig.; the arti-
culation between Re I and II
is almost wanting posteriorly;
-the St. has 50—60 short teeth.

The Se of Ri I is well devel- ; Text-fig. 41. Chirudina notacantha G. O. Sars.

‘ y a. fg. Head X 30. b. abdomen etc. & 30. c—d. Pes V dext. Ri + ReIovlIl from
op ed but without an acces the right and partly from behind x c.50. e. Pes V Ri sin. x 66. f. Pes V sin. Re
sory tooth in the Jourth par Il—IlI 75. g. yo (St. V) rostrum. h-—i. (St. V) fifth thoracic tergite from the left
and from above. j. (St. V) furca X 29. k. (St. V) Pes V in ant. view X 29.

of legs, and the inner margin
of the second basipodite is completely smooth. The only difference between the male and female is
found in the 7th parr of legs in the male (text-fig. 41k); this is distinctly different from the preceding
species by the segmentation of the left exopodite and by the wanting terminal setae. The /adrum ete.
is scarcely different from that of Cr. Streetsi (cf. text-fig. 38a); along the transverse ridge which limits
the labrum in front about 10 rather delicate setae are found. The oral surface of the labrum (Pl. VI
fig. 1a) is rather characteristic, though showing most similarity to that of Ch. Streetsi; the supporting
chitinous framework is less developed. The frst group of the longitudinal series consists of numerous
short spinules; the second group consists of a single longitudinal row of fairly long setae; the ¢hird

150 COPEPODA

to fifth groups consist of an inner more or less longitudinal row of fairly long setae inwards and of
more irregularly placed setae laterally; a s¢xth group of very short delicate setae is found; the trans-
verse rows are, as seen in figs, like those of Chzrudina Streetstt. The lamina ladialis (Pl. VI fig. 1b) is
not quite like that of any of the examined species, as it consists, as shown in figure, of two rather
independent portions. The arrangement of the setae in front of the row is like that of Chirudina Streetstt,
but no granular area was observed. The arrangement of the series upon and behind the labial lobes is
in its main feature like that of C. abyssalis (Pl. VI fig. 1b; cf Pl. V fig. 5f). Laterally a similar tuft
of hairs is found as in Ch, pustulifera,

£5 (St. VI). Size of specimen from Thor St. 183 was 6'7 mm.,; anterior division 5°2 mm.; urosome I'5 mm,

The head is rounded, with fairly slender rostral spine (text-fig. 41 a). The body is more slender
than in the female; the articulation between the head and the first thoracic tergite is only indistinct;
the lateral spine of the thorax is placed more dorsally, is more slender and apparently starts from the
fifth somite, The comparatively slender abdomen is about one third of the anterior division, and has, as
seen in text-fig. 41 b, the genital opening on the left side, and has a seam of short, delicate teeth along
the posterior margins of somites II~IV, The furcal rami are somewhat wider than long; the St. 2 is
somewhat longer than the abdomen. The anztennulae extend about to the end of the second abdominal
somite; the segment ro is partly fused with 8~9, the segment 12 with 13, but the segments 21 and
22 are well separated on both sides; “A%sthetasken” are only wanting in segments 20, 23 and 24; the
measurements are very similar to those of the young ones, The exopodite of the antennae is only 13
as long as the endopodite; the Re I and II are indistinctly separated, and both possess a rudimentary
setigerous process, but the antennae are in other respects like the female. The mandibula scarcely
differs from that of Ch, Streetsi. The maxillulae possess in Ii at least 10 soft-skinned ringed appen-
dages as well as two short setae of usual structure, in Li II, which is fairly long, 3 soft appen-
dages, and in LillII 5 setae of usual structure are found; the basipodite III has 5 setae, the Ri I—II
have 7 setae, and the Ri III has 7 as well; the exopodite has 10 long setae and a short delicate inner
one, and the Le has 2 short basal ones and 5 long distal ones. The maxiillae are soft-skinned, but they
are better developed than in most other species of this family; the Lob. I—IV are well developed, and
possess 2 to 3 setae, and so does Lob. V, but its Sp. is strong and not twisted; the Re has 6 setae. The
maxtlipeds are in main feature like those of Ch, Streetsii; their third basipodite is 2°5 as long as Ri
and 1°5 as long as the two basal segments.

The first pair of legs has the articulation between Re I—II better developed, and the Se Re I
is quite rudimentary ; the three last natatory legs are scarcely different from those of the young specimens.

The right fifth foot has a rather short third basipodite; the right endopodite has some similarity
to that of Ch, Streedsii, is terminally gutter-shaped on the anterior surface, but has somewhat proximally
to its end laterally a rounded incision (text-fig. 41 c); the outline of the endopodite is rather irregular, but
no marginal laminae or teeth were observed in proximal half. The right exopodite has the two first
segments fused, and is, observed from in front, distinctly convex towards the middle; the third segment
is obtusely rounded, is rather elongate and possesses marginally a distinct lamina (text-figs 41c—d), The
third basipodite of the /e/t foot is long, almost attaining the middle of Re IwII; the left endopodite
(text-fig. 41 e) is unsegmented, and is, as shown in fig., distinctly narrow somewhat beyond the middle.

oe eee

COPEPODA 151

The first segment of the left exopodite is fairly long and slender, while the second, as shown in text-
fig. 41 f, is broad and widened out terminally, where a bifurcate spine is seen; the third segment (Pl. V
fig. 7 a) is distinctly widened out towards the end and produced inwards, where the usual tuft of mar-
ginal setae is observed; on the posterior surface groups of delicate hairs are found. Inwards at the
base of Re III, a partly independent, lobe is observed with groups of fairly long hairs posteriorly.

The outline of the /adrum is, as seen in fig., very similar to that of the female, but the whole
apparatus is soft-skinned without any setae, but adorned with an intricate systeme of chitinous ridges;
two labial lobes are present with a longitudinal furrow between.

Parasites. In one specimen twisted structures like those described in Gazdius tenuispinus
(p. 92) were attached behind both maxillae; in another specimen a similar organ was found behind
the one maxilla only, but in that specimen a “sac-shaped parasite?” was found attached to the LiI
of the left maxillula.

Occurrence. The Thor Expedition has '/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire
gathered 3 young females, 11 adult males and g young males.

The Monaco Expedition has taken immature females at two stations, and Farran has recorded
adult males as well as immature ones from the west coast of Ireland “on four stations from depths of
600 to 1150 fathoms”.

Remarks. I am pretty well convinced that the described species is identical with Sars’ Gazdius
notacanthus, in spite of a few differences from the somewhat meagre description, viz: in the antennulae,
which are not “presque aussi longues que le corps”. The male is probably identical with that described
by Farran. The male, which Scott has referred to this species, is 599 mm. long and has rounded
lateral corners; accordingly it is not the male of Cz. xofacantha, and it may more naturally be regarded
as the male of Ch. pustulifera. Sars and Farran as well as the other authors have provisionally
referred this species to Gazdiws, as the adult females are not yet known. Several structural features
have, however, gonvinced me that this species like Ch. parvispina, and probably also Gatdius validus
Farran (1908, p. 32), G. cryptospinus G. O. Sars (1905, p. 10), dvaricatus G. O. Sars (p. 10) and G. maximus
Wolf. (1906, p. 2), is nearly related to Undeuchete spectabilis G. O. Sars (1900) p. 59 as well as to Chz-
rudina Streets, pustulifera and abyssalis. It differs from Gaidius tenuispinus etc. by the three-seg-
mented exopodite of the first pair of legs with well developed Se Re I, by the wanting setae along
the inner margin of the second basipodite in the fourth pair of legs in the young specimens of the
fifth stage, as well as by the structure of the oral surface of the labrum and the lamina labialis.

All the described males referred to this genus show a marked similarity to Undeuchete in the
structure of the fifth pair of legs, and are accordingly different from those of Gazdius and Gaetanus.

44. Chirudina parvispina Farran.
(Pl. V figs 8a; text-figs 42a-g and 43 a-h.)

1900? Undencheete spectabilis n. sp. G. O. Sars, pp. 59—63, pls XV—XVI.
1908. Gaidius parvispinus n. sp. Farran, pp. 34—35, pl. II figs 4—8.

Description. rg (St. V). Size of young male from Thor St. 183 was 51 mm.; anterior division

414 mm.; urosome 0:96 mm. Young female measured 442 mm. Farran’s specimens measured 479 mm.

152 COPEPODA

The rostrum is strong and directed downwards. The head is, in contrast to Farran’s fig. 4,
well separated from the first thoracic tergite. The fifth somite is well developed and bears a short,
downwards directed hooked spine (text-fig. 42). The abdomen differs from that of the preceding species
by being less hairy. The antennulae extend to the end of the chephalosome; the mouth appendages
are scarcely different from those of Ch. molacantha. In the structure of the natatory legs scarcely any
difference was observed between this and the preceding species. The ¢hrd foot is shown in text-fig.
42e. The only difference between male and female is found in the presence of a fifth pair of legs in
the former sex; this pair of legs (text-fig. 42 g) is in most respects like that of the preceding species, but
differs by the equal length of the two exopodites as well as in a few minor points.

In the structure of the /adrum and its surroundings no difference of great interest was observed

. between this species and the
g d

preceding ones (cf. Pl. VI figs
1 a—b).
Y§ (St. IV). Size of male
from Thor St. 183 was 3°46 mm.;
anterior division 2°81 mm.; uro-
some 065 mm.

The body is more slender,
and so is the rostrum; the

lateral corners are somewhat

~ more robust (text-fig. 43 f). The

abdomen consists of three seg-
Fig. 42. Ch. parvispina Farr. Yo (St. V). ments as shown in text-fig.
a. Left lateral corner X29. b. Third basipodite of mandibula x50. c. Pes II 43f The mouth appendages

X 33. d. Pes II Re III; glandular pore < 57. ¢. Pes III sin. K 29. f. Second

basipodite of pes IV. g. Pes V in ant. view X 33. show the usual differences. The

exopodite of the /irst pair of
legs shows no ttace of segmentation, but has three well developed Se. The endopodite of the second
pair of legs is unsegmented, and the two last segments of the exopodite are fused, bearing 3 Se and a
single glandular pore at the base of Se 3. The inner margin of the second basipodite of the /ourth
pair of legs is smooth. The only difference between the male and female is found in the 7th pair of
legs, which, as shown in text-fig. 43 h, is less developed than in the preceding stage.
fg. Size of male from Thor St. 183 was 5:28 mm.; anterior division 4°15 mm.; urosome 1°3 mm.
The rostrum (text-fig. 43 a) is somewhat shorter, and the lateral spines of the end of the thorax,
which are placed less dorsally, are more slender and extend a little beyond the hinder margin; the
fifth thoracic tergite is not distinctly marke@out. The abdomen (text-fig. 43 b) is scarcely different from
that of Ch. notacantha.
The antennulae extend beyond the end of first abdominal somite. The two basal segments of
the exopodites are well separated in the antennae, and the maxillae have the setae of the first lobes
somewhat contorted, and the Sp. of the lob. V more swollen at the base, but in other respects the

mouth-limbs were like those of the male of Ch. notacantha.

.
q
4
4
‘
‘
4
4
j
A
a
‘
r

COPEPODA 153
The frst pair of legs has the inner margin of the third basipodite less produced than in the

preceding species; the Se of Re I is rather short, but strong, and the Se of Re IJ, which is fairly strong,

extends only a little beyond the middle of Re III; the other natatory legs are scarcely different.

The fifth pair of legs is in main features like that of Ch. motacantha, but differs in several de-
tails. The right endopodite (text-fig. 43 c) has a more regular shape, and has a somewhat different shape
terminally; the third segment of the right exopodite (text-fig. 43 c) has, inwards, characteristic incisions
and processes. The left endopodite has a more regular shape, and is terminally produced into a short
tooth (text-fig. 43d). The second segment of the exopodite is of more equal breadth throughout, and
the third segment is distinctly more slender (text-fig. 43 e); the arrangement of the series of hairs on
the posterior surface of Re III shows characteristic features of specific value (fig. 8a Pl. V}.

é

Text-fig. 43. Chirudina parvispina Farr.
a. fg. Abdomen X 22. b. Head X 22.. c. Pes V dext. Ri+ Re Xc.50. d. Pes V Risin. X 66. e. Pes V sin. Re II—III
X75. £ yo (Stage IV). Head x 66. g. Abdomen x 66. h. Pes V X c. 80.

Occurrence. The S/S Thor has gathered this species at two stations viz:

11/, 1904 St. 183. 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 fd, 2 yo (V), 2 y2(V),.1 vy? (IV), t yo (IV).
to/, 1904 St. 180 61°34 L. N. 19°03 L. W. Yt. 1800 M. Wire 1 yo (V).

This species has only been recorded by Farran from the west coast of Ireland between 580
and 680 fathoms at 54°53 L. N. 10°42 L. W. in the month of November 1904, and at 54°57 L. N. 10°51
L. W. in the month of February rgo5.

Remarks. The specimen (yoting male) described by Farran is scarcely different from my
specimens. The female is perhaps identical with Und. spectabilis G. O. Sars (1900, p. 59), which is, how-
ever, much bigger (f? 8 mm.), but in other respects, except by the shorter Se of Re I pes I, is scarcely

different in any features of importance. If, however, Sars’ male (6 mm. long) and female really belong
The Ingolf-Expedition. III. 4. 20

154 COPEPODA

to the same species (they were gathered in the same sample at 84° L. N., “the tow-net having been
lowered to 130 metres”), Ch. parvispina and sfectabilis are scarcely identical, as Sars’ male possessed

a rounded lateral corner and a distinctly more elongate third segment in the exopodite of the fifth foot.

Valdiviella Steuer.

1883? Eucheete pars Brady. 1908. Valdiviella Steuer. Farran.
1904. Valdiviella n. gen. Steuer. 1909. _ — A.Scott.
1905. — Steuer. G. O. Sars. IgII. _ — Wolfenden.

According to G. O. Sars and Wolfenden this genus is nearly related to Euchete; the
structure of the maxillulae and the maxillae bear out this opinion. With some right Steuer suggests
that it ought to be referred to the Aetidezdae; the structure of the legs, of the labrum, the labium and
the antennulae support this view. On account of the two egg-balls and the distinctly three-segmented basi-
podite of the maxillulae, I think that the form is a rather primitive one. V. oligarthra Steuer, insignis
Farran and érevicornis G. O. Sars, as well as the curious V. minor Wolf. are certainly good species
A. Scott has referred a young male, probably belonging to this genus, to Brady’s Zuwc. gigas; he is
certainly wrong; his specimens are from the Malayan Seas and Brady’s from the west coast of South-
America; the length of the former was 8 mm. and of the latter 5:25 mm. The lateral corner of Brady’s

specimens had a long lateral spine, that of Scott’s species a short triangular one.

45. Valdiviella insignis Farran.
(Pl. VI figs 2a—e; text-figs 44 a—d).
1908. Valdiviella insignis n, sp. Farran, pp. 45—46, pl. III figs ; 1911. Valdiviella insignis Farran. Wolfenden, pp. 247—248,
1—6, pl. IV fig. 5. Taf. XXXX figs 6—7.

Description. £9. Size of specimen from St. 183 was 11°75 mm.; anterior division 8:5 mm.; urosome
325mm. Farran’s specimens measured 11°5—12°0 mm.

The anterior division, which has distinctly rounded lateral corners without tuft of hairs, is
rather clumsy; the rostrum consists of two short, well separated spines; the first thoracic somite is com-
pletely fused with the head, and the fourth with the fifth. The anterior division is 2°5 as long as the
abdomen, which has the proportional length as 45, 35, 25; 11, 11. The genital somite is almost sym-
metrical and only slightly produced below; the vulva is seen laterally as an incision between an
anterior and posterior process. The somites III—IV have ventrally a tuft of long hairs; the posterior
margins, not only of the III—IV tergites but also of the Iw II, are denticulated. The furcal rami and
the setae are scarcely different from Farran’s description; the appendicular seta seems to be longer
than figured by Wolfenden. ‘

The antennulae, which extend a little beyond the end of the thorax, have not the obtuse angle
between the proximal and distal portion, which is found in Zuchete; the segments 8&9 and 246 25
are almost completely fused. The ringed terminal setae are less powerful than those found in Zuchede;
no proximal setae were found in segments 10, 11 and 20—23; rather short triangularly pointed “Alsthe-

tasken” were observed in segments 5, 9, 12, 14 and 19, The measurements are even in minor details

COPEPODA 155

like Farran’s description and very characteristic; the segments 89 are 1°3 as long as segment 7, and
again 1'2 as long as 13; the segment 17, which is three times as long as the segment 14, is a little
longer than the segment 19, and 14 as long as 2425. The basipodite III of the ez¢ennac has a single
well developed seta; the Ril has 2 fairly long setae, and the Li of Ri II has at least 7 longer and
shorter setae, The exopodite is a little longer than the endopodite; its first segment is well developed
without any seta, and the second has a short terminal seta. The mandibulae have the teeth developed
in a curious way, as shown in Farran’s fig. 3; the basipodite III possesses proximally a fairly long
somewhat curved seta and, medially, a short one; the Ri I has at least one seta, and the Ri II 8
powerful long setae, and more medially, a fairly long slender one. The maxillu/ae have in general
shape some similarity to Huchete; in the Le were found only 6 well developed setae, of which the
third is the longest in several specimens, and not 7 as figured by Farran (fig. 5), as the proximal
was probably wanting; the Li I has only 11 setae, as S 12—14 on the posterior surface are missing;
corresponding to Li II—III only a single lobe with 4 setae was found. The Basp. III has 1 seta, the
Ri I 2 and the Ri IIw III 3 strong setae. Three basal segments are easily recognized in this species;
the Basp. I is adorned with Li I, the Basp. II with Li II and Le I, and the Basp, II, which is well
articulated, has the two branches. The maxillae are like Farran’s fig. 4 Pl. III; the first basipodite
has the exterior margin distinctly concave in the middle; the Lob. I—IV have posteriorly a distinct
spinous area. The proportional length of the segments in the maxzllipeds is 60, 90, 26; they are scarcely
different from those of V. oligarthra,

The es J has the Ri I—II completely fused, and the Re I is only indicated by a medial incision
and a powerful Se; as shown in fig. 2a, a glandular canal and pore was present in the exterior margin
of the second and third division; the pore in the former was covered by a spine-shaped mass, and
both pores were surrounded by numerous hairs, The Zes // has the distinction between Re I—II indicated
by a medial incision and a well developed lateral spine; the articular membrane is anteriorly repre-
sented by a faint line, which is not seen posteriorly, The unsegmented Ri has near the tip on the
anterior surface a minute pore (text-fig. 44b). Near the base of Se Re II and Se 3 Re III but not
in Re I, wide glandular pores are found, in connection with big sacs with glandular cells, which are
placed proximally to the articular membranes between the Re I—II and Re II—III respectively. The
pes IT differs from pes II by the distinct articular line between Ri II—III; a distinct glandular pore
is found at the base of Se Re I; the ges /V is in main features like pes III, but the Basp. II has
comparatively few hairs along the inner margin.

The epistoma is represented by a short protuberance, which is placed somewhat behind the
insertion of the antennulae; it is steep in front, and smoothly sloping behind, and appears quite smooth.
The /abrum is rather prominent; on the anterior surface, somewhat in front of the free margin, a trans-
verse row of fairly long stiff hairs (fig. 2b) is observed; and more laterally, partly covered by this,
an oblique row; and along the hinder margin the usual row of numerous somewhat curled hairs (fig. 2 e).

The oral surface of the /abrum (fig. 2c) has the group 1 placed laterally, and consisting of
numerous short setae or granules; the group 2, which is well separated from this, and consists of
comparatively few longer setae, is closely followed by groups 3—4; the group 5 consists of more

numerous and comparatively longer setae.
20*

156 COPEPODA

The /amina labialis does not show any features of interest (fig. 2d); the area in front of it is most
like that of Chzrzdius; it consists of a lateral, somewhat convex, row of fairly long setae and two median,
well separated, groups, as shown in fig. Behind the lamina and between the labial lobes, which were
not studied in detail, no setae were observed.

Y¢% (St. V). Size of specimen from St. 183 was 9 mm.; anterior division 65 mm.; urosome 2°5 mm.

The shape of the body is in main respects like that of the females, but the lateral corner of
the thorax has a small tooth; of the four abdominal somites the second is longer than the third, which
is as long as the first. The measurements of the antennulae are somewhat different; the segments
17 and 19, which are of equal length, are 1:24 as long as 2425, and 2°5 as long as segment 14. The
other appendages do not seem to show differences of any importance; the Re of the maxillulae pos-
sess, as usttal in this stage, only ro setae. The pes V of the male is somewhat like that of Zuchete;
the Ri, which is almost twice as long on the right side as on the left side, is distally rounded without

, : any spines; the Re, which are of almost
equal length, are continued into a rather
strong spine (St), and have on each side
one or two Se, as well as 2 or 3 Si. The
structure of the pes V is distinctly diffe-
rent from Scott's fig. 26 of the corres-
ponding pair of legs in V. gigas, as well as
from Brady’s fig. 5 of Zuchete gigas.

Y (St. ID). Specimen from Thor

St. 183: 5°58 mm.; anterior division 4°5;

Text-fig. 44. Valdiviella insignis Farr. urosome 1:08.
a. £9. Abdomen < 8. b. £9. Pes III RilII in anterior yiew with gland X 59.

c. Yo (St. V). Left lateral corner x 16. d. Yo(St. V). Pes Vin ant. view X 18. The rostrum and the frontal parts

are like those of the adult females; the
lateral corners are neither produced nor pointed; the first as well as the fifth thoracic tergites are well
marked out. The abdomen consists of two somites, of which the terminal one is almost twice as long
as the basal one.

The antennulae extend almost to the end of the abdomen; the “A¥sthetasken” are as in the
adults, but the Spr. was only observed in segment 19. The measurements are distinctly different, as
the distal segments are comparatively longer; the segment 19 is 1-3 as long as 17, and scarcely 11 as
long as 2425, which is 1-2 as long as 17. The mouth appendages, except the maxillulac, are practically
like those of the adult; the Le had in the single specimen examined a single proximal long seta and
3 very delicate hairs distally; the Li I has only 1o setae, and the Re as usually 8.

The pes / differs distinctly from that of the adult by the more slender form especially of Ri;
both branches are undivided; the 3 Se are well developed, and a glandular pore is found in the third
division. The ges // has both branches unsegmented; the Re I—III has 6 Si and 4 Se; only at the
base of Se 3 Re III is a glandular pore found. The ses /V is comparatively more slender than pes I];
the Re Iw III have 3 Si and 3 Se, and a single glandular pore; the Ri I~ III have 6 setae altogether.
In lateral. view the labrum and labial appendages are scarcely different from those of the adult.

Le ie i lin tk

COPEPODA 157

Occurrence etc. The S/S Thor has twice gathered a few specimens of this interesting species, viz:

11/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 3 f? (one with 2, the others with single egg-
sac), 2 yd (V), ry (III).
to/, 1904 St. 180 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 4f9 (one with 2 egg-sacs), 1 yo (V).

On the west coast of Ireland “three specimens of this species were taken at depths of 700, 730
_ and 1150 fathoms. By Wolfenden it has been recorded at about 20° L. S. and 20° L. W. On account
of the longer antennulae and well developed Se Re I pes II I think with Farran, in contrast to

Wolfenden, that this species is well distinguished from V. oligarthra Steuer from the South Atlantic.

Eucheetidae.
Euchzte Philippi 1843.

A. Scott has established a new genus (1911 p. 64) Pareuchete with L. norvegica as a type in
contrast to the true Zuchete with E. marina as type species; the latter is characterized by the fifth
pair of the legs in the male, which has the Re III of the left foot elongated and pointed, and in
the females “two of the six apical spines on the first maxilliped, in addition to being furnished with
rows of very short spinules have also a number of moderately long and conspicuous spinules”. The
latter characteristic is very interesting, but probably not important enough for the establishment of
a new genus, especially as a single apical seta of the mentioned structure was found in £& hebes, in
which pes V of the male is of the Z. morvegica type; in £. acu¢a only a single seta of this structure
was found.

In spite of specific variations the structure of the epistoma, and the anterior and posterior surface
of the labrum show, as seen by comparing the figures on Pl. VI and the descriptions, common features;
the arrangement of the hairs in front of the lamina labialis is fairly characteristic.

The arrangement of the glandular pores in the legs does not show specific difference of great
value. In the outer margin of Re III pes I, somewhat beyond the middle, a glandular pore was found,
alike, but less distinctly developed than the corresponding pore in Valdiviella insignis Farr. (Pl. VI fig.
2a). In the second pair of legs a pore is found at the base of Se Re II and Se 3 Re III as well as
one minute one near the tip of Ri III; in the third and fourth pair, in addition to these, a pore is
found at the base of Se Re I.

In this genus the adult females show the most characteristic systematic features, especially
in the structure of the genital somite; it must be remembered, however, that the usual inspection of
the genital area from the side and from below is not quite satisfactory for a full estimation of the
characters. A full dissection is often necessary to understand the complicated structures of the vulva;
unfortunately, I have not had the opportunity of doing so at the present. The characters found in the
number of setae in the maxillulae, as well as in the relative length of the spines in the exopodite of
the second pair of legs are of value, but often show some variations. To refer the copepodites as well

as the adult males to the right species is often impossible.

158 COPEPODA

As a good deal of confusion exists as regards the determination of several species, I think the

following synoptic key of the adult females may be useful.

ve One of the apical setae of the maxillae with numerous short spinules and
a few long ones. Lateral corner rounded.
a The genital somite on the left side with a conical process. 4mm. £. acuta,
3, The genital somite on the left side dorsally a hairy process. On the right
side of the vulva a laminous process, 35mm. £. hebes,
I, All the apical setae of the maxillae of the usual structure.
2. Si of the furca distinctly shorter and thinner than St. 2. Lateral corner rounded.
The posterior process of the vulva longer than the anterior. iomm. £. glacialis,
3. Si of the furca distinctly longer than St. 2.
4. Lateral corner pointed.
x Lateral corner triangularly pointed without tuft of hairs 66 mm. £. Zonsa.
%. Lateral corner with a well defined pointed process; distinct tuft of hairs. On
each side of vulva a median process, 88mm, £, norvegica.
4. Lateral corner rounded.
6. 3 distinct processes on each side of the rather low genital protuberance.
56mm, &, bisinuata,
6. Without 3 distinct processes on the same level.
7. Genital protuberance very deep, almost squarely truncate with a small median
process on each side of the vulva. ee linha 67mm. £. gracilis,
7, Genital protuberance not very deep. On each side of the vulva in front of
the posterior edge a laminous process.
8. Dorsally and behind on the protuberance small process. Le maxillulae with
g setae. Se Re I pes I long and slender, 89g mm. L. Hanseniz,
8. No such process observed.
9. On the left side of the genital somite a conical process found
10. The Se 2 Re III pes II does not extend to end of segment 11mm. £. Farrant.
10. The Se 2 Re III pes II extends beyond end of segment 8mm. £. barbata,
9. On the left side of the genital somite no conical process found. Se Re I

pes I small or wanting.
11. The genital protuberance is prominent with short anterior frange. 82mm. £ Brady.
11. The genital protuberance not very prominent
12. Shape of body clumsy. 6mm, L£. Scotts.
12. Shape of body rather slender. 95 mm. £. Sars,

46. Eucheete norvegica Boeck.
(Pl. VI figs 3a—f; text-figs 45 a—s.}

1864? Eucheete pestandreae Philippi. Boeck, p. 12. | 1885 pars. Euchzete norvegica Boeck. G. O. Sars, p. 234, t. 19.
1872. _ norvegica n. sp. Boeck, p. 4o. 1892. _ — —- Giesbrecht, p. 246, taf.
1873. — carinata n. sp. Mébius, p. 271, tab, VII. | 15, 16 and 37,

COPEPODA 159

1898 pars. Euchzete norvegica Boeck. Giesbrecht & Schmeil, p. 40. | 1904. Eucheete norvegica Boeck. Wolfenden, p. 133.

1898. — — — Aurivillius, pp. 89—g0. 1905. — — — G.O.Sars, p.5.
1899. — — — Th Scott, pp. 248 —249. 1905. _ — — Farran, p. 35.
1900 pars. — a — G.O.Sars, p. 58. pl. XIV. 1907. — — — Damas & Koefoed, p. 396, 407.
1902? — = — Mrazek, p. 515. 1906 pars. — — — Pearson, p. 16.
1903. — — — G. O. Sars, pp. 38—39, pl. | 1908. _ — — _ v. Bremen, p. 52—53 fig. 59.
XIV—XVI. 1908. — _ — Farran, p. 4o.
1903. — — — Norman, p. 137. IgII. — ~ — Farran, pp. 95—96.
1903. — -= — Jensen, Johansen, Levin- | 1913. _ = — Stephensen, p. 320.
sen, p. 86, tabel II.

Description. £9. Size: One of the largest specimens (Thor St. 183) anterior division (2°76 + 3°68);
posterior division 2:42; total length 886 mm. Sars’ females measured 8 mm. and Giesbrecht’s 85,

j a
Text-fig. 45. Zuchete norvegica Boeck.
a, £9. Pes I in anterior view X57. b. In posterior view < 57. c. fd. Lateral corner of the thorax from the left 18.
d. From the right 18. e. Pes V Ri sin. in internal view. f—g. YQ and yo (Stage V). Abdomen X12. h. Yo (St. V).
Furea X 18. i. Pes V X 28. j—k. YQ-—c (St. IV). Abdomen « 16. 1. Yo (St. IV). PesV X 65. m. Y (St. III). Rostrum X 59.
n. Y (St. II). Rostrum xX 59. 0. Y (St. II). Animal in dorsal view 18. p. Y (St. II). Abdomen in lateral view x 59. q. Y
(St. II). Maxillipes sin. in posterior view 59. 1. Y (St. II). Pes I sin. in post. view X57. s. Y (St. II). Pes III sin. in post.
view X 57.

The last thoracic somite has laterally a minute tooth as figured by Sars; in one specimen it
was wanting on the right side. The genital somite has in front of the prominent ventral protuberance,
which possesses a small tooth on each side of the vulva, a characteristic small tubercle.

The frst pair of legs (text-figs 45 a—b) has the articular line between Re I and II rather com-
plete posteriorly; anteriorly it is wanting, except inwards, where a chitinous line is observed, to which
a muscle is attached. The glandular pores are rather indistinct; in the Aes // they were only observed
at the base of Se Re II and Se 3 Re III and terminally in the middle of Ri; in the two following pairs
pores, even if indistinct, were observed besides at base of Se Re I.

160 COPEPODA

Between the insertion of the antennae, (Pl. VI figs 3a—c.) an efstoma, directed forwards
and terminally covered with long, stiff bristles is found; between this and the well developed labrum,
which is gradually sloping anteriorly, a rather shallow portion is found; anteriorly the labrum is
marked off by a chitinous transverse convex list, where the longitudinal muscles are fastened, which
move the marginal fringe of setae. The labrum bears.in the middle two rather irregular rows of more
or less slender bristles. The marginal fringe consists in the middle on the well developed lobes of a
right and left group of fairly long hairs; more laterally a group of shorter hairs is found; orally an in-
distinct transverse row is found (cf. Pl. VI fig. 3a). The chitinous framework which supports the oral
surface of the labrum is in the main like, but less developed than, that of Auchirella messinensis (cf.
Pl. IV fig. 2a). In addition to the usual four central spots, 6 spots are present on each side. Just be-
hind the spots Nr. 4 a transverse group of short spines is found. The first lateral group of the longi-
tudinal series of delicate hairs is placed transversely, and fairly well separated from the more longitudinally
placed group 2; this again is well separated from the more or less fused groups 3—5, as seen in fig. 3a.

The lamina labialis (fig. 3b) is divided into a median and, on each side, two lateral serrations,
which are connected with a chitinous skeleton. The area in front has, as shown in fig. 3b, a rather
complicated structure; on each side, in the middle, a granular area converging in front, is found, and
more laterally several slightly convex longitudinal series of delicate hairs as well as a square spinous area
just in front of the serrula 6-dentata; the latter is, as seen in fig. 3b, placed on a well developed chitinous
system. Behind and between the branches of the lamina labialis about 5 oblique rows of delicate hairs
are found on each side. MObius has given a fairly good description of the oral surface of the labrum
and the lamina labialis. The /adzal lobes (fig. 3 c), which are well developed and rather prominent, pos-
sess about 5 somewhat irregular longitudinal series of comparatively short hairs, which, posteriorly, are
fused into fairly big median groups. The region behind the area labialis proper does not possess any
group of delicate hairs, but somewhat medially to the articular cavities of the maxillae is found a
group of 15—20 long, stiff setae, directed inwards and almost attaining the middle; in the middle, more
posteriorly, a group of 1o shorter setae, directed forwards, is found.

fg. Size: In one of the largest specimens (Thor St. 183) the total length was 6°34; anterior divi-
sion (2°53 + 1°95) 4°48; urosome 186 mm. Sars’ males measured 7 mm, and Giesbrecht’s 5'45.

The lateral corner of the fifth thoracic somite (text-figs 45 c—d) is distinctly more produced on
the left side than on the right; dorsally, a small marginal tooth is found, more developed on the left
side. The first abdominal somite has the genital pore on the left side, and is somewhat produced on
the right side; on the same side laterally and dorsally near the base of the somite a triangular tooth
is found. The segments 12—13 of the axtennulae are well separated on the left side, but have on
the right side the articular membrane indistinct, posteriorly. The measurements are practically like
those in the adult females. The Ri of the az/ennae has on the interior lobe 5 plumous setae, even
longer than in the female, in addition to two short ones. The mandibulac possess, in contrast to Sars’
and Giesbrecht’s description, a well developed, but soft-skinned, manducatory part with 4 short mar-
ginal teeth (Pl. VI fig.3e). The maxzllulae are better developed than described by Sars and Gies-
brecht, though they are probably without value for mastigation. The Le has 5 strong setae; the
Li 1 possesses at least three delicate bristles, the Li 2 a single short one and the Li 3 a single

Ne See EHP ee ae ea Ue Fee ee Pee re ee

COPEPODA 161

somewhat longer; the Basp. 2 has 4, and the Ri at least 5 setae. The Re has 10+ 1 setae. The max-
wlae are quite rudimentary soft-skinned, somewhat twisted organs possessing the usual number of
lobes, which bear soft appendages, on the distal lobes most like setae. The maxillipeds are less powerful
than those of the female, the Lil of the basipodite 1~2 has one hair, Li 2 one short hair, Li 3 two
hairs and Liga single hair in addition to a hooked organ surrounded by fine hairs like that of Z.
bisinuata Farran (Pl. VI fig. 11¢).

The second pair of legs differs distinctly from that of the female by the short Se Re II, which
only reaches the end of the segment, far removed from the base of Se 1 Re III.

The Re II—III sin. of the 7th fair of legs (Pl. VI fig. 3d) are in the main like Giesbrecht’s
fig. 24 (Taf. 16), differing from Sars’ by two not one, rows of serrations, between which the seg-
ment is distinctly more hollowed than in the two following species. The left endopodite consists of
two segments (text-fig. 45 e).

The epistoma and labrum are in lateral outline seen to be distinctly lower than those of the
females; by further examination (Pl. VI fig. 3¢) it was found to be poorly developed, without labial
lamina and distinct labial lobes; the complicated system of hairs found in the females seems to be
completely wanting. ,

¥3 (St. Y). Size of specimen from Thor St. 183: the total length 5:57 mm.; anterior division
(246 + 1°79) 4:25; urosome 1°42.

The shape of the anterior portion differs hort that of the f? by triangularly pointed lateral cor-
ners (text-figs 45f—g). The abdominal somites show the usual differences; in constrast to the £9, the Si
of the furca is distinctly shorter than the St. 2 (text-fig. 45 h). The axtennulae are comparatively shorter,
but the arrangement of the appendages is completely like that of the £9; the measurements are,
however, slightly different; the segments 24~ 25 are at least as long as the segment 19, not 1:2 shorter,
as the segment 23 is 1:1 as long as, not rz as short as, the segment 16, The Re of the maxillulae
possess only 10 setae. The Re I—II of the first pair of legs are es fused without trace of
segmentation.

The male of this stage is easily distinguished from the female by the presence of a fairly well
developed two-branched fifth pair of legs (text-figs 45 g and i).

ey (St. IV). Size of a big specimen from St. 183 was 36 mm.; anterior division (1-7 + 10) =
2°7; urosome o'90 mm.

This stage differs from the preceding one by the urosome, which consists of three somites only
(text-figs 45 j—k), of which the last is the longest, the first the shortest; the subapical seta is, as in
the preceding stage, shorter than St. 2. The antennulae have the appendages like the adult females, and
the measurements show corresponding differences; the segments 24 25, f. inst. are distinctly 1-2 as long
as the segment .19. The Re of the maxillulae possess only 9 setae, as usual in this stage. The exopodite
of the first pair of legs is alone unsegmented, as not only Re I—II are fused but also Re II—III. The
Re IH—III of pes II—III are fused with 3 Se, of which Ser Re II~III pes II is comparatively wes
probably corresponding to Se Re II. The Ri II—III are fused in pes III—IV.

The Ingolf-Expedition. III. 4. 2I

162 COPEPODA

The male of this stage differs from the female by the fairly well developed ~~ pair of -_
ieee: 45 1).

St. III. Size of specimen from Ingolf St. 19 was 2°65 im. long; anterior division (1:26 + 063)
= 1°89; urosome 0'76 mm. i ;

The rostrum is less prominent (text-fig. 45 m), and the lateral corners are regularly rounded;
the abdomen consists of two somites only; the subapical seta is, as in £9, much longer than St. 2. The
antennulae extend almost to the end of the furca; the usual long setae, which are more powerful in the
segment 7, are found, but the number of the short setae is much smaller, as the fused segments (400 5)
(23) have only a single seta, as the segment 6—10 do not posses any, and as Spr. is only found in
segment 19. No “2Psthetasken” were found in segment 12, but, as usual, in segments 5, 9, 14 and 18. The
measurements are distinctly different as the segments 19—24 are comparatively longer than in the pre-
ceding stages; the segments 24% 25 are 1°3 as long as segment 19. The mouth appendages are in the
main like those of the adult females, but the number of the setae is as a whole a little smaller, f£ inst,
the Re of the maxillulae has only 8 setae. The two first pairs of legs are scarcely different from stage
IV; the pes III has in Re IIWIII only 2 Se and 4 Si, and the Ri is undivided; the pes IV has Re I—III

fused with a basal Se well separated from two distal ones.

St. II, Size of specimen from Ingolf St. 19 was 1-79 mm. long; anterior division (oma 4)
= 1'33; urosome 046. ;

The lateral corner of the anterior division is not regularly rounded, and the rudimentary fourth
pair of legs is found as a wing-like expansion (text-figs 45 n—p). The subapical seta (Si) is thicker and
longer than the St. The antennulae, which almost extend to the end of the urosome, have several of
the proximal segments (1—18) more or less fused. A long distal seta is found in segments 3~ 4, 6% 7,
14 and 18. No “isthetasken” were found. Beyond the segment 18 the segments become suddenly longer;
the 19 is almost twice as long as the 18; the segments 19—23 are of almost equal length; the seg-
ments 24 25 are 13 as long as 19. The mouth appendages show similar differences as in the preceding
stages; the maxillulae have only 7 setae in Re; the maxillae are less powerfully developed, as seen in
fig. 3f The maxillipeds have only 2 setae in the middle of basipodite 3, as the median one is wanting.
The Ri possesses only 5 setae.

The es J is comparatively more clumsy; 3 Se are present, as in the preceding stages. The
pes II has the Re I indicated with well developed Se; in addition, 2 Se and 4 Si were found. The Jes 7/7
is like the Jes /V of the preceding stage, with 3 Se and 3 Si (text-figs 45 r—s).

Occurrence. Davis Strait. The Danish Ingolf Expedition has in the southern part of the Davis
Strait as far north as 65° L. N. from 25/6—*8/, 1895 taken g samples containing Auch. norvegica; in the
following 5 a fairly big number was found. In the table (p. 163) a few stations south and south east
of Greenland are dealt with.

As the species was found neither in any surface sample nor more north than 65°, there is reason
to suppose that the form does not belong to the fauna of the surface, but belongs to the northern
prolongation of the Atlantic fauna. Propagation has been found to take place at the mentioned season

in this region.

4
4
:
.

COPEPODA 163

‘Depth in Temp. at ‘eats eee, V IV Number of
1895, | Ingolf | L. N. | L. W. | fathoms Ill II I specimens
and net, | SUtface. 3 Q 3 Q 3 Q examined.
1/7 | St. 28. | 65°17 | 55°42 | V.t10o—o0 | rI5°C} .. 10 : To 16 I
—+ | St.27 | 64°54 | 55°ro | V.t200—0 | 379° C. <4 4 fe 4 7 2 3 I
25/6 | St. 25 | 63°30 | 54°25 | V.t200—-0 | 2°99. GC.) 2%Fo | 24 o/o 5%/o |. 7%0 | 14%0] 15%} 30%} 3%) 2. Il 115
25/6 | St. 24 | 63°06 | 56°00 | V.t200—0 | 4°2° C.'}, 7% | 34%03] 20%/0 |.30% | 5°%/o} 3°%/0| 1%} -.. 163
28/, | St.36 | 61°50 | 56°21 | “Trawl. a us 1.
— — st -. | Vit 100—0. oe a, © be ». | 34% | 30%] 15%} 15%} 5%] .. Ve 120
3/,° | St. 38 | 59°12 | §1°05 | V.tI0O—0 | 10° CGC... <p Ee 8 5 2 6 |
22/6 | St. 22 | 58°10 | 48°25 | V.t200—0 | 5°35° CG.’ .. “4 4 3 3 I I
20/6 | St. 20 | 58°20 | 40°48 | V.t200—0 | 61° C. wa 6 10 18 6 6 .| 19 I
18/6 | St. 19 | 60°29 | 34°14 | V.z300—-0| 9° CH .. | 8 oo .20 Fo | 33 %/0 | 20%o | 9%} 9%} L%o} ws. Ih. 1ST
7/6 | St. 18 | 61°44 | 30°29 | V.1200—0 | 10° = C. }}. 5 %/o | 24%o |.22%0 | 26%0| 9%} 9%] 5%] -. Jeb ii 163

1 Means that spermatophores were found attached to the genital somite of the females or to pes V of the males,
2
- egg-sacs -_ oo — =

Denmark Strait. The Ingolf Expedition has in Denmark Strait (2°*8/s 96) taken 5 samples con-
taining 2. norv., but only few specimens (stage V most numerous; a single fg‘ was found); in 1895 a
single sample (St. 11) with a fairly big number of specimens was found. The S/S Thor has at four
stations from **°/, t904 taken numerous specimens with the young-fish trawl, among which were several
adult males with spermatophores attached to the fifth pair of legs, as well as females with eggs and
spermatophores. The table shows the relation between the different stages.

LN. aw. |. Depth and oe hk ibe 2 i ut |r| 1 aprons
Bet face 3 Q 3 9 3 Qe 4 examined.

Ingolf 21/5 95 | St.11 | 64°34 | 31°12 | V.t 200—ofm. | 82°C] .. | 33 ne 27 5 6
Thor 18/6 04 St. 150 65°50 | 26°53 | Yt. 400 M.Wire as re 12 5 15 II 3

18/6 04 | St. 152| 65°00 | 28°10 | Yt. 800 M.Wire e 20 Oo 16 oo 75 °lo|, 7%Fo |22°5 Yo 27%}... |.. | -- 365

19/6 O4 a ee .. | Yt. 1000 M. Wire Li 15 ; a2), I is 2 5

20/6 04 | St. 153 | 65°27 | 27°12 | Yt. 800 M.Wire ‘a 24 : at. = ne 25 25

21/6 04 | St. 154] 65°27 | 27°10 | Yt. 800M.Wire| .. ree ey oe 4%o| 5 oe 36 %o | 27% | 1%}... | .. 110

South of Iceland. South-west of Iceland the Ingolf has taken a few, mostly young, specimens in
5 samples; a single sample from the deep sea contained an adult female with spermatophore, in the
others from surface-hauls copepodites of stages V—IV, were found, but no adult.

In the Atlantic, south of Iceland, the Ingolf Expedition has (3/6 96 and 9/s 95) taken 4 surface
samples with a few young specimens of stages IV—V; and in addition to these 7 samples from lower
layers, of which 5 contained adult specimens. The S/S Thor has in this region taken 11 samples (?4/.
1904, #/,—%4/, 1903—04 and-"/, 1904), which all contained adult specimens.

2

164 COPEPODA
Temp. VI Vv IV Number of
LN. VL. W. net. at sur- ; Ill} IL specimens
face. 3 Q 3 Q 3 Q examined.
Ingolf 3/6 96 | St. 68 | 62°06 | 22°30 | V.t 100—ofm. | 88°C} 1 9 i I5 36 2 I |r
. 3/6 96 | St. 69 | 62°40 | 22°17 | V.t 100—ofm. | 7°3°C. 5 ole 12% | 75°%0} 5%/0 | 3% 100
1/6 96 | St. 63 | 62°40 | 19°05 | V.t too—ofm. | 8:3°C.|} 1% | 4 ole 22 Uo | 63°%o} 6% | 4%o 174
9/8 95 | St. 40 | 62°00 | 21°36 | V.t 100—ofm. |13°5°C. 25). 5 4
13/5 96 | St. 49 | 62°07 | .15°08.| V.t 100-—-ofm. | 93°C I 20 2 bit|!s
12/. 96 | St.47 | 61°42 | 13°14 | Vt 100—ofm. |10°6°C. |}. 4 21} 2 .8 I
Thor 9/7 04 | St.178| 63°11 | 21°30 | Yt. 780 M.Wire 6% | 33%o | 20%o | 23 %0| 12%0} 6% 163
10/7 04 | St. 180] 61°34 | 19°03 | Yt. 400 M.Wire I 20! | 22 BK) 16 12
= _ Yt. 1800 M. Wire I I
1/, 04 | St. 285} 62°49 | 18°46 | Yt. 500 M.Wire 1% | 35 ole 21% | 11%/0 | 17 %/o | 15 Po 170
11/, o4 | St. 183 | 61°30 | 17°08 | Yt. 1800 M.Wire 10 oo 19 oo 32 %/o | 24%/0| 8% | 7% 1235
24/5 04 | St. 104} 62°47 | 15°03 | Yt. 1500 M.Wire 51 oo 39 ole 1°5 %e | 1°5%/0| 2% | 5% 217

The presence of adult males and the presence

of females with spermatophores and egg-sacs

certainly indicate that propagation takes place or has taken place; at St. 183, where among 230 f? 60

had spermatophores and had 3 egg-balls, but especially at St. 104, where 30 of 110 fo had sperma-

tophores attached to the fifth pair of legs, and 50 of 85 £2 wore spermatophores and 15 wore egg-balls, a

great number of specimens certainly are active in propagating the species.

Iceland-Feroe Channel. The Ingolf Expedition has not found any adult specimens in two

samples taken near the surface from the Iceland-Feeroe channel, but in

those (four) from the deeper

L.N.|L.W.| Depth and net, | Te™P- at is M 4 ut | 1 pie :
surface. 3 9 3 9 3] Q examined.
Ingolf 15/596 | St. 52 | 63°57 | 13°32|| V.t 200—ofm. | 8:3° C. 4 I 7 3 II k
20/.96 | St. 57 |63°37|13°02]| V. 1oo—ofm. | 82° C 4 I 35 | 3 | 14 4}2 q
1/596 | — |61°32| 10°47 Cyl. 14 a : I II 7 6 :
11/596 | St. 45| 61°31} 9°43] V.2 too—ofm. | 91°C 90 12 of 5% | 46%/o |8%/o| 6%o | 11%/o|3%o} .. 100
Thor 23/504 | St. 102 | 61°41 | 13°31 || Yt. 15 M. Wire Atal 2 se 17 3 6
28/3 05 | St. 163 | 62°36] 12°05 || Yt. 300 M. Wire tr) 24 | 9 ale a a
22/504 | St. 99| 61°15} 9°35|| Trawl. goo M. 28 22, I “6
— _- Yt. 1000 M. Wire 12 oo 55 olo 2% |. 11%/o | § Yo} 12%o | 3% 100
— _ Yt. 1700 M. Wire 9 Poy I "7 I 8
5/504 | St. 63 |64°05| 9°38 — 5. 36. 6 : 3 I
12/,04 | St. 78| 61°08 | 9°20 — 15 13.
9/504 | St. 70|63°33| 6°20) Yt. 100 M. Wire 96 ole 1°5 lo] 2°°5°/0 156
33/7 05 | St. 124] 61°04] 4°33] Yt. 1000 M. Wire I x. 2

COPEPODA 165

layers had always found adult females. The S/S Thor has taken samples at 15 stations; adult specimens

were found at all except two. Adult males have been found from the month of May till August.
North of Iceland. North and north-east of Iceland the Ingolf Expedition has at 4 stations

taken a few young specimens, and at one adult females. The S/S Thor has at a single station

taken a fairly large number of adult specimens.

Ingolf 2/s 96 St. 128 66°50 L. N. 20°02 L. W. Trawl. 1d (V), 12(V):
10/, 96 St. 102 66°23 L. N. 10°26 L. W. V.2 roo—o fm. Temp. at surface 03°C. 2£9, x (III).
23/, 96 St. 117 69°13 L. N. 8°13 L. W. V2 100—0 fm. _ 41° C. 1 (III), 2 (II).
24/, 96 12.30 a. m. St. 118 68°27 L. N. 8°20. W. Closing net 1o30fm. — 1 ?(V), 1 2(IV).
Thor 72/, 04 St. 214 67°19 L. N. 17°55 L. W. Yt. 800 M. Wire 11 fd, 35 2 (eggs

sperm.), 2 (V); 2h (IV).

‘South of the Feroes. The S/S Thor has in the Atlantic, south-west of the Feeroes, at six
stations taken adult males and females; in the samples enumerated below the number of specimens

was fairly big; at 5 of 6 stations south-east of the Feroes adult females were found.

: VI Vv | Iv Number of
1905 | Thor. | L.N. | L. W. Depth and net. TII | II | I || specimens
; 3 9 3 Q 3 Q examined.
3t/g | St. 167 | 57°46 | 9°55 W. Yt.. 300 M. Wire I 10 3 3 od 2
— — ei Se Yt. 1500 M. Wire 12 46. 14 7 5 5
8/6 | St. 72 | 57°52.|9°53 W. Yt. 1500 M. Wire 43 ole 32 ole 8 oo II% | 2°5%} 2°5%0/1%0 | ...| .. 311
20/6 | St. 88 *48°09 8°30 W. Yt. 300 M. Wire © 38° 56 20 9
2t/6 st. go | 47°33 | 7°40 W. Yt. 300 M. Wire 10 18° 5 4 we I
se ou a = Yt. 500 M. Wire = 1 ze a I
6/y | St.172 | 57°33 | 4°26 E. Yt. 300 M. Wire 35 40 5 7 5 5 4
6g | St.173 | 57°52 | 8°or E. || Yt. 800 and 300 M. Wire 3 : y I 8 I

East-Greenland Expedit. That scarcely any specimens were taken in the numerous surface
hauls during the crossing of the Danish East-Greenland Expedition 1900 (June—September), in the
Norwegian Sea, in the ocean east of Greenland, in Denmark Strait and the Atlantic south of Iceland,
seems to indicate that the species is extremely scarce at the surface.

In vertical samples from near the coast of Greenland a few specimens were found. As so few
specimens have been taken, I think a full account of the stations may be useful.

25/6 1900 Jan Mayen. Closing net 60~50 fathoms 1 y (III).

4/, 3p.m. 73°32 N. 3°30 W. Vertical. 300—o m. 1 £9.

8/, 2p.m. 74°28 N. 15°36 W. oe 400—o m. rig, 5 £9, 1 K(V), 1 2 (V).
ro/, 6 a.m. 74°28 N. 15°36 W. — § 100—o m.’ If (V), 12 (V).

eee bee as — Closing net 110—40 fath. 1 $ (IV).

166 COPEPODA

3/5 12 p.m. 68°22 N. 17°15 W. F. 300 1 2 (V).

18/, 12 p.m. Kap Dan —.° | F. 347 1 of (V).
24/, 10 p.m. 61°06 N. 16°26 W. F. 391 1 dh (V); 1 oh (IV).
12 p.m. 1 » -F. 392 1 2(IV).

Distribution. LEuchete norvegica is recorded from the Atlantic at least as far south as 51° L. N.
from the west coast of Greenland at little Karajak-Fjord (Vanh6éffen), and north of Iceland (Paul-
sen). It has been found abundantly in the Feroe channels, and in the Norwegian Sea, but only in the
northern part of the North Sea. It is, according to Sars, frequent in deeper layers along the whole
coast of Norway, and so it is in the Skager Rak. It is recoded as common in the Barents Sea. The most
common species of Zwchete found in the Polar basin crossed by Nansen was £. glacialis, not nor-
vegica as originally proposed by Sars, but the latter species was nevertheless (Sars 1903 p. 39) found
occasionally in two different places. As Mrazek says that his specimens attain a length of about
1o mm., he has probably confounded the two species. ‘

Euchete norvegica has been taken by the Duc @Orléans (from 7/,—"/g 1905) at most stations
between c. 10° Long. East and the east coast of Greenland as far north as 80° Lat. North, but was never
common. The species was never common between c. 300—100 meters, where adult females with ovi-
sacs or spermatophores and males (sometimes with spermatophores attached to pes V) were often found;
between o—100 met. mature specimens were never found, but now and then a few young ones (1907
p. 407). Wolfenden has found the same to be the case in the Atlantic and writes (p. 133) “Young
and undeveloped specimens are not uncommon near the surface, but the adult animal appears to prefer
the deep water down to 500~600 fathoms”. My material, as far as it goes, tells the same story.

Though the species has a wide distribution in the northern seas, and though it is occasionally
found propagating here, I think we are right in regarding it as a species which belongs to the North
Atlantic, and by the Atlantic currents are carried to the polar regions; it seems in any case to be
distinctly more’ common in the Feroe channels and the west of Iceland than in the ocean between

Norway, Greenland and Spitsbergen.

47. Euchzte tonsa Giesbrecht.
(Pl. VI figs 4a-—b; text-figs 46 a—g).

1895. Eucheete tonsa n. sp. Giesbrecht, p, 251, pl. IV figs 9—10. | 1906. Eucheete tonsa Giesbr. Hsterly, p. 64, pls 9—10.

1898. — — Giesbr. Giesbrecht & Schmeil, p. 4o. 1908. — oe — vy. Bremen, p. 55, fig. 62.

1904. — _ — Cleve, p. 190. : 1908. Hes. at ahve: Brant aot

1905. _ — > — ..G.0O.Sars, p. 5. 1909. — — — .. A. Scott, p. 72, pl. XIV figs 8—15,.
1905. _ — — Farran, p. 35. IgII. — _ ~ Wolfenden, p. 298, text-figs 50a-d.
1906. — — —. Peatson, p.'17. ;

Description. 9. Size of specimen from St. 72 Thor 1905 was 64 mm.; head +- first thoracic
tergite 28, four posterior thoracic somites 18; urosome 1’8 mm.

The lateral corner is like Wolfenden’s figure, and more pointed. than figured by Scott and
Esterly for Pacific species; the point is, as shown in text-figs.46a—b, more prominent on the left than
on the right side; no lateral tuft of hairs is found.

COPEPODA 167

The genital somite is, as seen in fig; 46a, distinctly produced below, but the outline is not quite
like any of the published drawings. The structure of the vulva seems to be a good deal more com-
plicated than figured by Wolfenden. The subapical seta is more slender, but longer than St. 2.

The antennulae are like Scott’s fig. 11; the segments 24 25 are distinctly shorter than seg-
ment 19, and 23 than 16. The mouth-appendages are scarcely different from those of Z. norvegica.

The fes J is in main features like Z. x., but distinctly different from Scott’s fig. 13; the arti-
cular membrane between Re I—II is fairly developed anteriorly, but posteriorly is wanting, except
medially; the Se Re I is fairly developed. The fes // is like Wolfenden’s fig. 50c, but in details
is different from Scott’s figure; the Se Re II scarcely reaches the base of Se 1 Re III, and Se 2 al-
most reaches the base of short Se 3. On the posterior surface of the second basipodite in the fourth
pair of legs.a number of delicate hairs are found in the middle.

The epistoma and outer surface of the labrum are in the main like those of uch. glacialts (cf. p. 169)
and slightly different from E. norv.. The oral surface of the Wyst
labrum is like E. norv, except the two first groups of
hairs, which are plaeed as shown in fig. 4a. The area
in front of the lamina labialis is like that of & xorv.,
but inwards delicate spines are found instead of sasieionsi
the most lateral group of hairs is almost as wide as long.
The /obus labialis possesses in similarity with Zuc. glacialis

a posterior lateral group of hairs. a een g
3. Size: 589 mm.; anterior division (2°56 -+ 1°6);

urosome 1°73. : ; ‘
Shape of the body is scarcely different from £. b

norv. The rostrum is a little more obtuse and somewhat

shorter. The lateral corners are rounded and somewhat

less produced, but more produced on the left than on

the right side; the difference is, however, less marked ©

than in £, norv. (text-fig. 46 c). J 2; 3 c
Text-fig. 46. Zuchete tonsa Giesbr.
a. £9. Genital somite * 16. b. £9. Lateral corner
of the thorax and are scarcely different from’ those of from the right 16 and x 52. c¢. fo. Lateral corner
- _ from the right «18. d. Pes V Risin. from the right
£. norv. (in situ) X 59. e. Yo'(?) (St. V) with abnormal pes V

The ges Z has a well developed articular mem- X16 f ¥o@) (St. V). Abnormal pes V X 39. g. yo
(St. V). Pes V in anterior view X 33.

The antennulae reach somewhat beyond the end

brane between Re I—II, and the Se Re I is very short,
scarcely three times as long as wide. The ges Z/ differs from by the slightly different shape of the
Se Re II—III, and by the Se 2, which does not reach the base of Se 3; the base of the process, pos-
sessing the Se 2 Re III, is, in Z. zorv., placed almost as near the end as the base, but is here placed
distinctly nearer the base than the tip.

The fifth pair of legs differs from that of Zac. morv. by the different shape and serration of
the process of Re II sin, which is distinctly longer, not shorter, than the ringed appendage (fig: 4 b),
and by the slightly different shape of the left endopodite (text-fig. 46 d).

168 COPEPODA

re (St. V). Size of specimen from Thor St. 82 1904 was 4°42 mm.; anterior division (2°07 -- 1°23)
= 333 urosome 1°12 mm. i

The body is somewhat more slender; the first abdominal somite is in some specimens rather
prominent ventrally; the lower surfaces of two last abdominal somites possess tufts of the fairly long hairs
sometimes represented in Z. zorv. The lateral corner of the thorax is less acutely pointed than in Z&. zorz.
(text-fig. 46e). The pes I has no articular membrane between Re I—II, and the Se I is extremely short;
the pes II is scarcely different from the adult females. The male only differs from the female by the
presence of a well developed fifth pair of legs; the Re sin. is rather obtusely truncate (text-fig. 46 g).

¥5 (St. IV). Size of f—? from St. 88 Thor 1905 was 3°34 mm.; anterior division (1°56 + 0:90)
= 246; urosome 088 mm.; male from St. 82 3:28 mm. and female 3°54 mm.

The body is more slender than in corresponding stage in £. morvegica, and the lateral corners
are less distinctly pointed. The Se 2 of Re II~III in the pes II almost reaches the base of Se 3 in
contrast to Z. norvegica, ‘The pes V of the male is scarcely different from that of the other species.

Variation. A young male (St. 82) (text-figs 46 e—f) had, as shown in fig., the fifth pair of legs
developed in a rather curious way; in another specimen the left lateral corner was evenly rounded,
but the right one pointed in the usual way.

Occurrence. The Thor Expedition has taken the species from the following stations in the

Atlantic south of Iceland (one west of Iceland), all in fairly deep layers,

1/, 1904 St. 183 61°30 L. N, 17°08 L. W. Yt. 1800 M. Wire 1 £3, 4 £2 (egg-balls + sperm.).
2t/, 1904 St. 154 67°27 L. N. 27°10 L. W. 1 £9.
15/6 1905 St.82 51°00 L. N. 11°43 L.W. Yt. 1200 M. Wire 11 £9 (2 with sperm.), 2 2 (V), 6 3 (V), 29

| (IV), 4d CV).
3t/g 1905 St. 167 57°46 L.N. 9°55 L.W. Yt. 1500 M. Wire 1 f? (sperm.), 1 & (IV).

8/6 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 4 f9.
20/, 1905 St. 88 48°09 L.N. 8°30 L. W. Yt. 300 M. Wire 2 £9, 1? (V), 1d (V), rQ (IV), 1d (IV).

Distribution. This species, or a nearly related, somewhat larger one, was recorded from the
Pacific by Giesbrecht and Esterly between 150 and 300 fathoms (1912, p. 321); it was gathered at
several stations in Malay waters by the Siboga Expedition. The Gauss Expedition has gathered the
species at two stations in the South Atlantic (c. 35° L. S. c. 10° L. W.), and at two stations in the Mid
Atlantic, On the west coast of Ireland it is, according to Farran, “a rather characteristic species in
deep water tow-nettings ranging from 400—1000 fathoms”. z

Remarks. That the described female is identical with that mentioned by Farran and Wolfenden
is scarcely doubtful. Farran’s specimens measured 4'95--5'25 inm., Wolfenden’s specimens measured
5—5'3 mm. The specimens from the Pacific are a good deal larger (Giesbrecht’s 61, Esterly’s 61 and
Scott’s 7 mm.), but as my adult females from the North-Atlantic measured up to 6:4 mm., the character
found in size is scarcely of great importance. The only character in which my specimens seem to
differ from Scott’s etc. is the more pointed lateral corners and the structure of pes I —II, especially
the long Se 2 of Re III pes II. At present I do not deem these characters important enough to

establish two species.

COPEPODA 169
Ee 3 =
That the copepodites of the stages V—IV belong to the same species as the adult females is

especially borne out by the curious structure of the Re III pes II. That the described male, which as
realised from the above remarks is rather difficult to distinguish from £. orvegica, is really the hitherto
undescribed male, is not quite certain; but, as 4. /omsa also in other respects (e. g. structure of the labrum,
of the young specimens) shows greater similarity to Z. xorvegica than to any other species, I prefer for
the present to refer the males and females to the same species.

48. Euchete glacialis H. J. Hansen.
(Pl. VI figs 5 a—d; text-figs 47 a—n.)

1886. Eucheete glacialis n sp. H. J. Hansen, p. 74, pl. XXIII | 1904. Eucheete glacialis Hansen. Wolfenden, pp. 134—135, figs

figs 5—5k, pl. XXIV figs 1—1d. eae Beeb
1900 pars. — norvegica Boeck. G. O. Sars, p. 58, pl. XIV, 1905. _ — — Th. Scott, pp. 222—223.
1g02 pars. — -- — Mrazek, p. 515. 1907. — _ _ Damas & Koefoed, p. 408.
1903. — glacialis Hansen. G. O. Sars, pp. 4o—41, pl. | 1908. — _ -- v. Bremen, p. 54 fig. 60.
XXVII. 1913. — _ _— Stephensen pp. 319—320.

Description. Size of specimen from Thor St. 154 1904 was 104 mm.; anterior division (4 + 35)
= 7'5; urosome 2:9 mm. Sars’ specimens measured 10 mm,

The lateral corner of the thorax is somewhat triangular, and possesses in most specimens a
minute rounded process, which is not figured by Wolfenden and Sars (text-figs 47a—c). The genital
protuberance is very prominent, and has on each side of the vulva, the ventral surface of which has
been figured by Wolfenden (p. 134), two distally rounded, lamelliform processes, of which the hindmost
is the longer. The subapical seta is distinctly shorter than the St. 2. The antennulae and mouth-limbs
do not differ from those of Ewch. norvegica in any features of importance.

The articular line between Re I and II pes I (text-figs 47d—e) is anteriorly wanting in the
middle, and that between Re II and III is only slightly developed, especially anteriorly. The Se 1 is
scarcely shorter than in Z. norvegica (cf. Wolfenden p. 134); the Se Re II is perhaps somewhat longer
than the corresponding Se in #7; but the difference is not so marked that any character can be
found in this feature.

The structure of the Jaérum is in the main like that of & norvegica; the arrangement of the
hairs on the oral surface differs in minor details; the lateral anterior group is placed transversely, and
consists of about 20 rather stiff, short hairs; a sixth group, fairly well separated from the fifth, is found.
The Jamina dabialis and the serrula 6-dentata are scarcely different, but the hairs in front of the lamina
are distinctly different, as seen in fig.5a Pl. VI, especially the lateral group, which consists of 3—4
longitudinal rows. The arrangement of the hairs on the labial lobes is somewhat different, as seen by
comparing figs 5b and 3c; especially the lateral basal group is better developed.

£3. Size of specimen from Thor St. 214 was 621 mm.; anterior division (2°65 + 1°95) = 4°;
urosome 161mm. Hansen’s specimens measured 7°7 and Sars’ 8 mm.

The lateral corners (text-fig. 47 f) are, in contrast to those of £. norvegica, almost symmetrical
and only slightly produced, as on the right side in the species mentioned; the dorsal marginal tooth
is only indicated, or is very short. The first abdominal somite does not on the right side possess

any dorsal lateral process.
The Ingolf-Expedition. III. 4. 22

170 COPEPODA

The antennulae extend about to the middle of the abdomen; the segments 12—13 are posteri-
orly fused, not only on the right but also on the left side. “A¥sthetasken” are found in all segments
except 23, even in the segment 20, in which they are wanting in Z. zorvegica. The measurements are
only in minor details different from those of the female. The interior lobe of the Ri of the antennae
has medially, in addition to the 5+ 2 setae, an extremely delicate one. The mandibulae and maxillae
scarcely differ from those of Z. norvegica. The maxillulae are, as seen in fig. 5 c Pl. VI, better developed
than in other species; the Lix has, f. inst, 9 fairly long setae, and so has the Ri. The maxzllipeds are
like those of Z. norvegica, but the usual hooked process of lob. IV Basp. II seems to be represented

by a rather slender, straight, conical process.

h i n k

f g j m 1
Text-fig. 47. Zuchete glacialis H. J. Hansen.
a—c. £9. Left lateral corner in three specimens; most setae missing «18. d—e. £9. Pes I dext. in anterior and posterior

view X57. £. fo. Left lateral corner X18. g. fo. Pes V Ri sin. in internal view. h—i. Yd—Q (stage V). Abdomen X 16.
j. Yo (st. V). Furca X18. k.. Yo (st. V). Pes V X 33. 1-—m. Yo—Q (st. IV): Abdomen X16, n, Yo (st. V). Pes V X 89.

Pes I has the articulation between the Re I—II better developed than in the female, but the
Se of Re I is wanting; the fes 77 shows a similar sexual difference.

Pes V dext. has, about in the middle, an almost complete articular line between Re I and IJ;
proximally to this a short tooth is found exteriorly, which is indicated in &. norvegica; the Re III is
terminally somewhat hollowed, and less widened. The Re II—III pes V sin, are distinctly shorter; the
ringed appendage is comparatively short, and the serrated process is moderately hollowed between the
two rows of teeth; the left endopodite has only one single segment (text-fig. 47 g).

vf (St. V). Size of specimen from Thor 1904 St. 154 was 7°71 mm.; anterior division (3°51 + 2°3)
= 581; urosome I'9 mm. Hansen’s specimen measured 7 mm.

This stage is easily distinguished from the corresponding stage of Z. norvegica by the more
obtusely ‘pointed lateral corner of the fifth thoracic somite (text-figs 47 h—j). The differences in the

COPEPODA 171

measurements of the terminal segments of the antennulae are like those of £. morvegica though less
marked; the articular membrane between Re I—II of pes I is not completely lost.

The fifth pair of legs in the male shows minute differences, as realised by comparing figures
(text-fig. 47 k).

¥§ (St. IV). Size of specimen from Thor St. 154 was 5:02 mm.; anterior division (2°3 + 1°43) = 3°73;
urosomn 1:29 min.

This stage differs from the corresponding stage of &. zorvegica by the more rounded lateral
corner of the thorax. The appendages show differences similar to those of £. morvegica (text-figs 47 1—n).

Occurrence. The Ingolf Expedition has taken the species at three stations only, viz:

26/6 1896 St. 94 64°56 L. N. 36°19 L. W. P. 100o—o Temp. at surface 25°C. 49 (V), ryd(V), trys (IV).
25/, 1896 St. 121 66°59 L. N. 13°11 L. W. V.!t 100—o _ 48° C. 1 £2, 4y? (V), 2yoh (V) ry (III).
27/, 1896 St. 117 69°13 L..N. 8°23 L. W. V.2 100—0 ~ 41°C. ry (V).

The Danish East Greenland Expedition 1900 has taken it at three stations.

4/, 3 p.m. 73°32 L. N. 3°30 L. W. 300—o meters 1 f? (with sperm.), t y? (V), ry} (IV).
81, 2 p.m. 74°09 L. N. 11°31 L. W. 400-0 —_ 1 £9, 3 y? (V), ryo (V).
1o/, 6 p.m. 74°28 L. N. 15°36 L.W. 400-0 — 1fd, 2y?(V), 3 yc (V), Ty? (IV), ryh (IV).

The S/S Thor has taken the species at 8 stations.

20/6 04 St. 153 65°20 L. N. 27°12'5 L. W. Yt. 800 M. Wire 1 y? (V), 6 yo (V).
21/6 04 St.154 65°27 L. N. 27°10 L.W. Yt. ? 16 £2 (2 with sperm.), 2 y? (V), 2 yo (V), 2 y?
(IV), 4 yh (IV).
Yt. 800 M. Wire 12f9, 2fd, 4y? (V), 4 yc (V).
22/, 04 St. 210 66°43 L. N. 18°10 L.W. Yt. 400 M. Wire 1 £9, 3 y? (V), 1 y? (IV).
22/, 04 St. 214 67°19 L. N. 17°55 L.W. Yt. 800 M. Wire 19 f? (3 with egg-balls), 3 fot, 1 yo (V), 1 yo (IV).
5/, 04 St.63 64°05 L.N. 9°38 L.W. Yt. 300 M. Wire 8£9, 6 y? (V), 6 yc (V).
4/, 04 St. 230 63°10 L. N. 7°31 L. W. Sy ee
9/, 04 St. 70 63°33 L.N. 6°20 L.W. Yt. 100 M, Wire 27 £2 (2 with sperm.), 5 fo, 5 y? (V), 3 yo (V),

°, p d 3 y? UV), trys (IV)..
%3/, 05 St.124 61°04 L.N. 4°33 L. W. Yt. 1000 M. Wire 1 f9.

Distribution. The species is very common in the Polar basin crossed by Nansen, “from 300
metres to the very surface of the sea”. By the Duc d’Orléans it was taken at 15 stations in the sea
between Spitzbergen and Greenland between 79°56 L. N. 1°29 L. E. and 71°22 L. N. 18°58 L. W. (*!/,—15/s
1905). Adult males and females partly with eggs and spermatophores were found at 5 stations between
200 and 500 metres; the young specimens were sometimes found in higher layers, but scarcely at the
surface; in the lower layers between 500—1000 metres young ones only have been found. In the Norwegian
Sea it has, according to Sars, been taken a few times between 200—1000 metres. Damas & Koefoed
write (p. 408) without mentioning the source: “Dans la mer de Norvége: jamais 4 la surface; princip-

alement au dela de 600 métres”. According to Wolfenden (1904, p. 133) “it is of rare occurrence in
22*

172 COPEPODA

the Fzeroe channel, and only once it occurred in the warm Atlantic area”, and according to Damas
& Koefoed “entre les Feeréer et ’Islande: pas au dessus de 400 métres” (p. 408).

My own records show that the species was fairly common in the ocean north of Iceland, and
in Denmark Strait; it has been found a few times in the Iceland—Feeroe channel and a single
time south-east of the Feroes. It is rather odd that it has not been taken in Davis Strait, but as
comparatively few deep sea samples have been examined from this region it is too early to exclude
the species from the fauna of this region. As it never occurred in any of the numerous samples brought
home by Thor and the Ingolf Exp. from the Atlantic south of Iceland, we are probably right in ex-

cluding it from the ordinary fauna of this region.

49. Euchete Farrani n. sp.
(Pl. VI fig. 6a; text-figs 48 a—d.)

1883. nec. Euchzete barbata n. sp. Brady, p. 66, pl. 22 figs | 1906. nec. Euchzete barbata Brady. Pearson, p. 17.

6—12. 1907. _~ — — Damas & Koefoed, p. 409.
1892. nec. — — Brady. Giesbrecht, p. 246. 1907. nec, _ _— — ©:G. O. Sars, p. 3.
1894. nec. — — — Th.Scott, p.58, pl. VI fig.17. | 1908. pars. — a — ov. Bremen, pp. 54—55.
1898. nec. — _ — Giesbrecht &Schmeil, p. 40. | 1909. nec. Pareuchzete barbata Brady. A. Scott, p. 70, pl. XVIIT
1900. pars. — norvegica Boeck. G. O, Sars, p. 234, pl. 19. figs 1—8.
1903. — barbata Brady. G.O.Sars, p. 41,pl. XXVIII. | 1909. nec. —_ Sarsi Farran. A. Scott, pp. 75—76, pl.
1904. pars. _ — — Wolfenden, p. 135. XXI figs 9—15.

Description. £9. Size of specimen from Thor St. 230 was 10°75 mm.; anterior division 8 mm.;
urosome 2°75 mm. Sars’ specimens measured 12 mm. :

The shape of the body is scarcely different from Sars’ figure; the anterior division, which has
a rounded lateral corner with a tuft of long hairs, is 2°5 as long as the urosome. On the ventral surface
of the third to fifth abdominal somites tufts of powerful hairs are found. The comparative length be-
tween the 3 first somites is as 50, 30, 25.

The genital somite (text-figs 48a—c), which is 1°2 as long as wide and 11 as long as deep, is al-
most as long as the following two combined; the ventral surface has a big protuberance for the vulva,
placed almost in the middle of the somite. In lateral view the ventral outline is anteriorly rounded,
in the middle almost straight, and posteriorly produced into a somewhat triangular process, which by
an incision is well separated from a “posterior process”, which really is the posterior limitation of the
vulva; this posterior process is basally marked by an incision. Somewhat more posteriorly and dorsally
than the base of the genital protuberance on the left side a small rounded process is found; this
process has been found in all the examined specimens, and is best seen when the somite is examined
in not quite lateral view. In ventral view the vulva is seen to be limited by a slightly prominent edge
behind; laterally it is partly covered by a wing-like expansion, which is rounded in front, and pro-
duced behind. In the middle of the vulva a chitinous “plate” is found, which in the posterior margin
has a median incision, laterally is partly fused and covered by a somewhat trilobated process, and in
front is in the middle covered by a posteriorly triangularly pointed plate. The St. 2 of the furca is
almost twice as long as the St. 1—4, but much shorter than the distinctly geniculate Si.

The antennulae, antennae, mandibulae, maxillae and maxillipeds do not show any feature of

COPEPODA 173

interest. The Le of the maxillulae show, however, some variation. In one specimen a single very
short hairy seta, a longer one and 5 very long ones were present on each side; in another specimen
1 fairly long + 5 very long were found on the left side, but 2 short + 5 long on the right side; in 3
specimens 2 short + 5 long setae were found on each side, and in one, on the left side, in addition to
the 5 long ones, one fairly long and one very short seta. The basipodite has '5 setae, the Ril 3, Ri II
4 (one very delicate), and the Ri III 3 setae.

The es 7 has the articular membrane between Re I—II fairly well developed anteriorly (text-
figs 48 b—c), and the Se Re I is fairly well developed. The Se Re II scarcely extends to the end of
the short Se r Re III, and the Se 2 Re III extends somewhat beyond the middle of the third division
(cf. Wolfenden’s fig. 9, p. 134). The epistoma, anterior surface of the labrum, and the labial lobes

c t e
' Text-fig. 48. Zuchete Farrani n. sp.
a—b. £9. Abdomen in dorsal and lateral view 18. c. £9. Vulva from below < 180. d. f9. Pes I dext. in post. view X 57.
e. Pes I dext. in ant. view X50. f. YQ. Lateral corner X 18.

seem in main features to be like Z. morvegica; the oral surface of the labrum is somewhat different
from £. norvegica, as seen by comparing figs 6a and 3a; the lateral anterior group has about 60 rather
strong short spines, the groups r—6 are more regularly placed. The area in front of the lamina labi-
alis differs by the less square, more rounded, lateral group of short hairs.

Y? (St. V). Size 83 mm.; anterior division 6 mm.; urosome 2°3 mm.

The lateral corners of the thorax are regularly rounded; in other respects, except the usual ones,
this stage is scarcely different from the adult females (text-fig. 48 f).

Occurrence. This species was gathered at the following stations by the Ingolf Expedition.
t/, 1896 St. 104 66°23 L.N. 7°25 L.W. P. 100—o fathoms Temp. at surf. 63°C. 5 £9.
t/, 1896 St. 105 65°34 L.N. 7°31 L. W. 2 Asesss, 58°C. 1 £9.

174 COPEPODA

24/, 1896 St. 11 °13 L. N. 8°23 L.W. V2 100—o fathoms Temp. at surf. 41°C. 1 £9.
7 7 3 3

25/, 1896 St. 118 68°27 L. N. 8°20 L. W. _ 49°C. 2 £9 (eggs+sperm.),
ty? (V).

25/, 1896 St. t20 67°29 L. N. 11°32 L. W. — sx °<" 2 £9.

t0/, 1896 St. 138 63°26 L. N.. 7°56 L. W. 1 £2 (eggs).

Deichmann has taken 2 f (with egg-balls) 70°32 L. N. 8°10 L. W. Depth 470 fathoms.
The S/S Thor has taken a single specimen south of Iceland at a typical Atlantic station as

well as from a few stations in the Iceland--Feeroe channel.

11/, 04 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 f9.

13/, 03 St. 164 62°10 L. N. 19°36 L. W. Trawl. riz

23/, 05 St. 124 61°04 L.N. 4°33 L.W. Yt. 1000 M. Wire 1 £9.

%/s 04 St.71 63°06 I. N. 6°20 L. W. Vt. 1500 M. Wire 7 £9 (x egg-ball), 1 y?.

4/3 04 St. 230 63°10 L. N. 7°31 L.W. Trawl. 1090 M.D. 27 £2 (2 with sperm., 4 with egg-balls).

Distribution. This species, according to Sars, has been taken several times in the Norwegian Sea
“by the aid of trawl” “and always in great depth down to 2000 fathoms”. By the Duc d’Orléans it was
taken */, 1200—1800 metres 79°34 L. N. 2°40 L. E., and *°/, 800—1350 metres 78°05 L. N. 5°21 lL. W.
The species seems most often to have been taken with the trawl; the few observations indicate that
the species belongs to the northern deep sea plankton, with its main distribution in the seas lying
between Iceland, Norway, Greenland and Spitsbergen, but it is sometimes found south of Iceland.
Curiously enough it has not yet been found either in Denmark nor in Davis Strait.

Remarks. Though the lateral tubercle of the left side of the genital somite is distinctly shown
neither in Sars’ nor in Wolifenden’s figures, I do not doubt that the described species is identical with
that described by the two authors. On account of the structure of the pes IT, Farran regards Wolf-
enden’s species as identical with his &. Sarsz; the size 10o—11 mm. and the structure of the vulva

(fig.5) make it necessary to refer at least some of the specimens to Z. Farrani.

50. Euchete barbata Brady.
(Pl. VI figs 8a—b; text-figs 49 a—p.)

1883.? Euchzete barbata n. sp. Brady, p.66, pl. XXII figs6—12. | 1906. Eucheete barbata Brady. Pearson, p. 17,

1892. — — Brady. Giesbrecht, p. 246. 1907. nec, — _- — Damas & Koefoed, p. 409.
1894. nec. — _ — Th. Scott, p. 58. 1907.? — _— — G.O. Sars, p. 3.

1898. _ ~ — Giesbrecht & Schmeil, p. 4o. 1908. pars. — — — vy. Bremen, pp. 54—55 fig. 61.
1903. ? — —- — Thompson & A. Scott, p. 244. | 1908. — -- — Farran, pp. 40—41, pl. III figs
1903. nec. — _ — G.O. Sars, p. 41, pl. XXVIII. I3—I4.
1904.? — _ — Wolfenden, p. 135. 1909.? Pareuchzete barbata Brady. A. Scott, p. 70, pl. XVIII
1905.? _ porrecta n. sp. G, O. Sars, p. 16. : figs 1—8.

Description. f£9. Size of specimen from St. 183 was 787 mm.; anterior division 5°75 mm.; uro-
some 2°12 mm. Another specimen measured 83mm. Farran’s specimens measured 8:1—88 mm.

The shape of the body is practically like that of the preceding species; the ventral surface of
the abdominal somites are less heavily hirsute. The comparative length between the 3 first abdominal

somites is as 42, 24, 24; the genital somite is 13 as long as wide and scarcely 1-3 as long as deep;

COPEPODA 175

the ventral protuberance is in lateral view scarcely different from £. Farrani; the anterior process is
comparatively shorter, but the posterior margin and the dorsal lateral process are scarcely different.
In the transverse chitinous plate no median incision was found posteriorly; covered by this plate a
chitinous system was found with a median incision (text-figs 49 a—d).

n 1 c b h

Text-fig. 49. Zuchete darbata Brady,
a—b. £9. Genital somite of two specimens in lateral view 16. c. £9. Genital somite « 16. d. Vulva x 180. e. f9. Pes I

dext. ant. view * 53. f—g. fo. Lateral corner from the left and right x 18. h. fo. Pes V dext. Re X57. i. Pes V Ri sin.

from inner side X 59. j. YQ (St. V). Abdomen 18. k. Furca of same specimen X 33. 1. Yo (St. V). Pes V X 33. m. Yo
(St. IV). Abdomen X 16. n. Yo (St. IV). Pes V X 57. o—p. Y (St. III). Rostrum and abdomen 16,

The measurements of the azt/ennulae show in the examined specimens a slight difference from

E. Farrani; the segments 24% 25 are slightly longer than, (not =) segment 19 and the segment 21 is

almost 1°1 as long as 17 (not as long as). The Le of the maxzllulae possesses in the examined specimens,

in addition to the usual 5 long setae, 2 shorter ones, showing from fairly long to very short variations.

176 COPEPODA

The es J (text-fig. 49 e) is scarcely different. The ses Z/ differs distinctly by the Se Re II, which al-
most extends to the end of the fairly long Se 1 Re III, and by the long Se 2, which extends to the
tip of the segment and to the base of the Se 3.

The anterior surface of the /2brwm shows an arrangement of the hairs most like that of Z Sarsi
(fig. 7a). The oral surface is like that of Z Farranz; the lateral group consists of about 40 hairs, placed
inwards in two rows, and outwards in one; about the difference in the arrangement of the other
groups I refer to fig.8a. In the arrangement of the hairs on labial lobes etc. no features of great
interest were found.

3. Size of specimen from St. 183 was 7:37 mm.; anterior division 5°3 mm.; urosome 2°07 mm.

The shape of the body is practically like that of Z norvegica; the rounded lateral corner is
more produced on the left side than on the right; the dorsal lateral process is more distinct on the
right side than on the left. The first abdominal somite has the dorsal process near the anterior border
prominent on the right side, and just indicated on the left (text-figs 4gf—g). The anxtennulae reach
just beyond the end of the cephalothorax; the segments 12—13 being without any articular membrane
posteriorly on the left side, but with a fairly distinct articular. membrane on the right side in some spec-
imens. No “A¥sthetasken” were found in segment 20. The segments 24 25 are 1'I as long as segment
15. The antennae, mandibulae and maxillae scarcely show features of interest; the mazxillulae have 8
setae in Ri, but do not differ from 2 morv. in other respects. The maxillipeds do not possess any
hooked process in the lob. IV of basipodite II, but 2 setae, of which the one is thicker. The Se of
Re I es J is extremely short and delicate. The jes // differs by the short Se Re II, which does not
reach the middle of the third division. The fes V dext. is scarcely different from F. zorzv.; it has a well
developed Se Re I, and trace of articular membrane between Re I and II. The ses V sin. has the Re
II—III comparatively shorter than £. morv., and has the serrated process fairly pointed, rather shallow,
and with a few distal teeth, comparatively strong, as shown in figure 8b. The left endopodite is
rather clumsy and has only a single segment (text-fig. 49 i).

*3 (St. V). Size: 614 mm.; anterior division 46 mm.; urosome 1°54 mm.

The lateral corner of the fifth thoracic somite, which is fairly well marked, is produced into a
rather blunt point. The first of the 4 abdominal somites is distinctly produced below in the females,
not in the single male. The appendages do not show features of great interest; the pes II is scarcely
different from that of the adult female. The Jes V (text-fig. 491) is like that figured in Z. tonsa, but
the St. are more developed. In a single female several of the furcal setae were more or less bifurcate

(text-figs 49j—k). The two last abdominal somites bear ventrally groups of rather short hairs.

vg (St. IV). Size: 4:49 mm.; anterior division 3°39 mm.; urosome IIo mm.

The lateral corners are slightly more pointed than in the preceding stage (text-fig. 49m); the
first of the 3 abdominal somites is barely produced below; only a single tuft of hairs is observed
near the hinder border of the last abdominal somite ventrally. The appendages show differences similar
to those described in Z. norv., f. inst, the segments 24 24 of the antennulae are 13 as long as the
segment 19 (text-fig. 49 n). ;

¥ (St. II). Size: 3:06 mm.; anterior division 237 mm.; urosome o69 mm.

COPEPODA 177

Apart from the bigger size and more straight rostrum, the stage is scarcely different from that
of £. norvegica (text-figs 49 o—p).

Occurrence. The S/S Thor has "/, 04 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire taken
919, 28d, 4¥9 (V), ryd (V), ay CV), ryd AV), ry (II) and */, 09 St. 180 61°34 L. N. 19°03 L. W.
Yt. 1800 M. Wire 1 f9.

Distribution. Remarks. About the distribution of this species only very little is known, as will
be understood from the following remarks. By Farrran it has been recorded as occurring “in small
numbers on five stations of from 700 to 1000 fathoms” off the west coast of Ireland. As neither Sars nor
Scott says anything about the characteristic tubercle on the left side of the genital somite, and as their
descriptions are not very perfect, I do not think that we should be right in including the Mid Atlantic
and the Indian Ocean within the range of this species. Farran, with some reluctance, refers his species
to Brady’s old species from 36° L. S. 46° L.W., on account of the corresponding size and similar structure of
pes II; Brady’s figure of the genital protuberance and the smooth ventral surface of the abdominal somites
III—IV seems to me to speak against the correctness of this view. The same opinion is shared by Wol1f-
enden, who regards &. darbata as more related to &. Wofendeni than to any other (cf. 1911, p. 300); as,
however, the name is now applied to a well defined species, and as there is no reason to hope for a

sure identification, I prefer to follow Farran in this respect.

51. Euchete Sarsi Farran.
(Pl. VI figs 7 a—b; text-figs 50a—f,)

1908. Eucheete Sarsi n. sp. Farran, p. 41, pl. III figs 15—16.
1909. ? == — Farr: A. Scott pp. 75—76, pl. XXI figs 9—15.

Description. 9. Size of specimen from St. 183 was 10 mm.; anterior division 7:3 mm.; urosome
27 mm. Farran’s specimens measured g'—10'2 mm.

The shape of the body ete. scarcely show features of interest. The anterior division is 2°7 as
long as the urosome; the proportional length of the abdominal segments is 45, 27, 27. The genital
somite has not on the left side the characteristic tibercle found in &. Farranz, and the ventral pro-
tuberance has the anterior process slightly concave in the middle, and the posterior process less
prominent than in the other species (text-figs 50a—e). The vulva is in the ventral surface quite dif-
ferent from that of &. Farrani and barbata. The median chitinous plate has posteriorly a median
incision, but the area in front is irregularly wrinkled, and the triangular plate is only indicated; the
trilobate process is very indistinct (text-fig. 50f). The segment 19 of the antennulae is 1-1 as long as
24~ 25. The Le of the maxillulae possess 2 extremely short and one longer seta proximally, and in addi-
tion to these the usual long ones distally. The ses 7 has a very short Se Re I. The Se of Re II extends
to the end of Se 1 Re III, and the Se 2 Re III extends somewhat beyond the middle of the third division.

The anterior surface of the /adrwm is distinctly different from that of Z. zorv. and Farrant, as
realised by comparing fig. 7a and the description of &. zorv. The oral surface of the labrum is very
much like that of 4. zorzv. The lateral group consists of 30—40 short spines; the groups 1—2 are placed

near to each other; the 3~—5 are fairly well separated. The arrangement of hairs in front of /amina
The Ingolf-Expedition. III. 4. 23

178 COPEPODA

labialis is most similar to that of Z. Scott7 (fig. rob); the large lateral group is almost completely fused
with the median, which, however, has longer hairs. ;
&. Size: 83 mm.; anterior division 5°5 mm.; urosome 2°8 mm. |

The rostrum is directed more forwards than in &. darbata Brady; the lateral dorsal teeth of
the last thoracic tergite are only slightly developed. The axtennulae extend distinctly beyond the end
of the cephalo-thorax; the segment 20 has a well developed “A%sthetask”; in other respects these organs
are scarcely different from those of Z. barbata. The maxtllipeds have in the lobe IV of Basp. II a well
developed, rather slender, hairy conical process, which terminally is produced into a delicate lash. The Se
of Rel es J is wanting. The ges // is practically like that of 4. darbata. The pes V dext. is scarcely
different from that of Z. darbata; the pes V sin. is in most respects like that of the other species;

Text-fig. 50. Huchete Sarsi Farran f9.

a—e. Abdomen of different specimens « 16. f. Vulva in ventral view 180.

the differences are best realised by comparing figs 7b and 8b; the best character is found in the ser-
rated process which is more slender, and has a less regular serration.

Occurrence. The S/S Thor has taken this species at the following deep sea stations.

11/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 3 f9.
t0/, 1904 St. 180 61°34 L. N. 19°03 L. W. Yt. 1800 M. Wire 1 f9.
3t/g 1905 St. 167 57°46 L.N. 9°55 L.W. Yt. 1500 M. Wire 1 fd.

‘Farran has recorded this species from three deep sea stations off the west coast of Ireland. _

Remarks. That the described females are identical with & Sarsc Farran, I regard as quite evi-
dent; in contrast to Farran I do not regard it as identical with Wolfenden’s &. barbata (cf. p. 174). The
described male is certainly different from that which has been referred to Z. darbata, and belongs cer-
tainly to &. Sarst or another species of similar size nearly related to it. I do not think that the male,
which A. Scott refers to Z Sarsi is identical with the described one, on account of the well developed
lateral dorsal teeth of the fifth thoracic tergite and the different shape of the serrated process.

tis co

COPEPODA 179

. 52. Euchzete Scotti Farran.
(Pl. VI figs 10a—c; text-figs 51 a—j.) ©
1908. Euchete Scotti n. sp. Farran, p. 42, pl. III figs r1—13.
IQII.? — — Farr. Wolfenden, pp. 301—302, pl. XXXV fig. 2, text-figs 53 a—c.
Description. £9. Size of specimen from St. 183 was 5°99 mm.; anterior division 4:26 mm.; uro-
some 173mm. Farran’s specimens measured 5°7—6:3 mm., Wolfenden’s specimens measured 4:2—
4°85 mm. — ;

The shape of the body is more robust than in the preceding species, as the anterior part is
only c¢. 2°3 as long as wide, and as wide as the urosome is long. The lateral corner of the cephalo-
thorax is not quite regularly rounded, but somewhat triangularly produced; the anterior division is 2°5
as long as the urosome, which shows the following proportion between the three first somites (15, 85,

Text-fig. 51. Zuchete Scotti Farran.

a—d. £9. Genital somite MoE | GEO. Vulva from below x 180, f. fg. Left corner X18. g—h. YQ—d (St. V). Abdomen
from the left x 24. i. Yo (St. V). Lateral corner & 15. j. Yo (St. V). Pes V & 15. Wiss

85). The genital somite, which is 13 as long as wide and 12 as long as deep, is in dorsal view slightly
asymmetrical, and has the lateral margins strongly convex, somewhat in front of the middle. The
genital protuberance has in lateral view a wing-like anterior process, sometimes slightly concave in the
middle, and a more dorsal and posterior process, separated from the former by a distinct incision (text-
figs 51 a—e). In ventral view the vulva shows some similarity to Wolfenden’s figure 53 a, which is,
however, too incomplete for a detailed comparison, and is distinctly different from the mentioned
species of this group. The posterior incision in the median plate is not observed; the anterior tri-
angular point, of which an oval plate is found, is just indicated.

The antennulae extend just beyond the end of the third thoracic tergite, but not to the end of
the cephalo-thorax; the segments 24. 25 are as long as the segment 19; the appendages scarcely show
differences from those of £. zorvegica. The mouth-limbs are scarcely different from those of £. darbata;

23*

180 COPEPODA

the Le of the maxzllulae possess 5 long + 2 shorter setae. This is in contrast to Wolfenden, who has
only found 5 setae in his specimens. The articular membrane between Re I—II of Jes 7 is barely in-
dicated, and the Se is, as pointed out by Wolfenden and Farran, extremely minute. The es // is
like Farran’s description; the Se Re II almost extends to the end of Se 1 Re III, and the Se 2 Re III
extends a little beyond the middle of the third division; in most of Wolfenden’s specimens the Se 2
reaches the end of the segment.

‘The anterior surface of the dabrum is in the arrangement of the setae scarcely different from
E. Sars (fig. 7 a); the oral surface is most like that of 4. zorvegica (fig. 10a); the lateral group consists
of about 10 fairly long, densely placed, setae: The first group of the longitudinal series, which is some-
what convex in front, is connected with group 2, which possesses fairly long setae, by delicate hairs
scattered inwards and outwards; groups 3—6 are fairly well separated, without difference between outer
and inner portion. The arrangement of the hairs on the area in front of the /amina labialis (fig. 10 b)
is in the main like that of & xorvegica, but shows, however, as realised by comparing figures, distinct
difference; the lateral group, f. inst., is almost completely fused with the median.

&. Size of specimen from St. 183 was 5°56 mm.; anterior division 3°93 mm.; urosome 1°63 mm.

The shape of the body is more clumsy than in &. morvegica; the anterior division is only 2°5
as long as wide, and 2:4 as long as the abdomen, the first somite of which is about 11 as long as
broad. The left side of the thorax is distinctly produced, and the dorsal lateral spine is represented
by a minute rounded eminence; on the right side no lateral spine is found (text-fig. 51 f). The dorsal
lateral process of the first abdominal somite is, as usually, best developed on the right side, but is not
very prominent, The axtennulae extend distinctly beyond the end of the cephalo-thorax; segments 12—13
have no articular membrane posteriorly; the segment 19 is I'9 as long as 24% 25; no “Asthetask” was
found in segment 20. The lob. IV of the Basp. II of the maxillipeds has in addition to a fairly long
slender seta a moderately long hairy process and a rather small conical protuberance; the other mouth-
limbs are scarcely different from those of the type-species. The Jes 7 has an extremely short Se in Re I;
the pes II is like that of &. barbata,

The fes V is shorter and more clumsy than in the mentioned species; the Re I—II pes V sin.
are most like the corresponding segments in £. barbata (fig. 10 c); the serrated process is narrow with
regular marginal serration.

yg (St. V). Size of 2 from St. 183 was 483 mm.; anterior division 3°63; urosome 12mm, ¢
(St. 183) measured 4°54 mm.

The shape of the body is, as in the adult specimens, more clumsy than the corresponding stages
of the related species. The lateral corner is, as shown in figure, triangularly, but obtusely, pointed. The
Se of the Re I fes 7 is comparatively long and slender. The females examined are distinctly different
from the male by the produced lower margin of the first somite; the pes V does not show characters
of great interest (text-figs 51 g—j).

Y@ (St. IV). Size of specimen from St. 183 was 334 mm.; anterior division 2-48 mm.; urosome
o'86 mm.

This stage differs from corresponding stage in related species by an obtusely pointed lateral corner,

Occurrence. The Thor Expedition has gathered this species at two stations only viz:

|
:
:

COPEPODA 181

m/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 37 £9:(3 with egg-balls, 2 with sperm.), 8 £3,

: 8 y@ (V), 4yh (V), ty (IV).
24/; 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1500 M. Wire 4 f9.

This species has previously been gathered off the west coast of Ireland “at depths of from 700
to 1000 fathoms” at five stations “but very few specimens were found on each occasion”. Wolfenden’s
specimens, which on account of the different shape of the genital somite (Pl. XX XV fig. 3) cannot with
security be referred to the same species, were gathered under the equator ca. 20° L. W. (depth 3000 m.)

53- Euchzte Hansenii n. sp.
(Text-figs 52 a—b.)

Description. Size; 8:9 mm.; anterior division 65 mm.; urosome 2:4 mm.

The shape of the body is like that of Z. xorvegica. The anterior division is 2°7 as long as the
urosome, which is only a little longer than the width of the thorax. The proportional length of the
abdominal somites is 45, 26, 25. The gemnztal somite is, laterally, more suddenly convex than in £. Sarsz,
and, as in this, the greatest width lies in the proximal ‘part; the genital somite is 13 as long as
wide, but only 11 as long as deep.
The lateral conical process which
characterises Z. barbata and Farrant,
is wanting. In lateral view the geni-
tal protuberance differs distinctly
from that of Z. Sarsi by the straight,
not concave, anterior process, and by
a fairly distinct process behind and
above the second one, sometimes
indicated in &, Sarsz, which, as usu-
ally, represents the posterior border
of the vulva. The ventral surface
is quite different; the triangular

plate in front is divided into three

processes; the transverse plate has h
Text-fig. 52. Huchete Hansenii n. sp.

posteriorly a median incision, on each ¢ ;
a. £9. Abdomen X16. b. Vulva in ventral view X 180.

side of which are two lobes (text-figs

52a—b). — The antennulae scarcely extend to the end of the cephalo-thorax; the appendages are
scarcely different from those of &. norvegica; the segment Ig is 11 as long as the segments 24 25.
The maxillulae possess in Ler two basal, fairly long and slender, setae, followed by 6 powerful seta
and one terminal somewhat shorter'one; the Basip. has 5, the Ril 3, Ri II 4 and the Ri III 3 setae.
The articular membrane between Re I—II is barely indicated, and the Se is long and slender. The Se
of Re I is fairly long, and extends almost to the base of Se 1 Re III, and the Se 2 Re III extends to
the base of Se 3.

182 COPEPODA

Remarks etc, Of this species the S/S Thor has *9/s 1905 St. 165 60°00 L. N. 10°35 L. W. taken
a single mutilated female. This species is nearly related to Z. Sarsz, but it easily distinguished by the
smaller size, by the structure of the genital somite, by the 9 setae in the Le of the maxillulae, and
by the well developed Se Re I pes IL.

54. Euchete Bradyi n. sp.
(Pl. VI fig. 9a; text-figs 53 a—b).
Description. Size: 80 mm.; anterior division 5°5 mm.; urosome 2°5 mm.
The anterior division is about 2:2 as long as the urosome, which is about as long as the
abdomen is wide. The lateral corner is rounded, with a heavy tuft of hairs. The proportional length

between the abdominal so-

——-s]|

mites is 40, 25, 25. The ventral
surface of the three last ab-
dominal somites possesses a
number of short delicate hairs.
The genital somite is 16 as
long as wide, but, on account
of the high ventral protuber-
ance, only rr as long as deep;
no posterior process is found
on the left side. The subapical
seta is broken, but is probably

Text-fig. 53. Zuchete Bradyi n. sp. £9. soeighe: than (hake
a—b. Abdomen X16. c. Vulva from below X 180, rior flange on the side of the
vulva is rather short, with
a somewhat convex outline, when observed in lateral view; the posterior margin is rather prominent.
The vulva is covered by the lateral flanges, in any case in front, to a greater extent than in the other
species; the triangular plate in front is indistinctly developed; posteriorly a median incision is found,
on each side of which a complicated chitinous framework is found (text-figs 53 a—c).
The antennulae extend somewhat beyond the end of the abdomen; the appendages are like
those of £. norvegica; the segments 2425 are 11 as long as segment 19. The Le of the maxillulae
possess two short and 5 long setae; the basipodite has 5, and the Ri 3 +4 + 3 setae. The other mouth-
limbs do not show features of any interest. |
The articular line between Re I—II fes / is indistinctly marked; the Se Re I is wanting, and
the concavity distal to its usual insertion is only moderate. The exterior outline of the Re III, which
in most species is more or less straight, is moderately convex towards the middle, and the usual
glandular pore is not seen. The Se Re II of the fes /7 extends almost to the tip of the Se 1 Re
III, and the Se 2 of this segment extends somewhat beyond the middle of the third division, but not
to the end of the segment.

¢
4

COPEPODA 183

The anterior surface of the /abrum has on each side, posteriorly, an area covered with fairly
long hairs; this group is almost fused with a transverse row of rather short hairs, which, without
interruption, is. continued from right to left. The oral surface has in the lateral group 40—50 short
spine-like hairs placed in a curved row; in the middle two distinct transverse rows, as seen in fig. 9 a.
The groups I—II, in the longitudinal series, meet as in uc. norv. under an angle; the groups
IIJ—IV have a smooth area in the middle, while the groups V—VI are compact. The groups of hairs
in front of the lamina labialis are in most respects like fig. 3b, but the lateral posterior group is more
elongate, and consists of fewer hairs.

Remarks etc. Of this species I have only examined a single female, taken 74/, 1896 St. 118
68°27 L. N. 8°20 L. W. Closing net 1030 fathoms by the Ingolf Expedition; it is probably nearly related
to E. barbata, but differs distinctly from it by the deep genital protuberance.

55. Euchete bisinuata G. O. Sars.
(Pl. VI figs rra—e; text-figs 54 a—j).
1907. itachsete bisinuata n. sp. G. O. Sars, p. 12. 1909. Eucheete bisinuata G. O. Sars. A. Scott, pp. 70o—71, pl.
1908. — — G.O.Sars. Farran, p.45, pl. III figs XVI figs 10—17.
t 17—19, pl. IV fig. 4. }
-' Description. £9. Size: 5°62 mm.; anterior division (2°58 + 1°59) = 417; urosome 1°45 mm. Sars’
specimens meastired 52mm.; Scott’s 5 mm.

The anterior division, which is distinctly twice as long as the urosome, is rather short and
clumsy with the lateral corners regularly rounded.

The genital somite is, seen from above, slightly asymmetrical with a well marked convexity
in front, somewhat behind ‘the base of the somite (text-figs 53a—c). The ventral outline shows 3
characteristic lobes, as figured by Farran and Scott. The posterior border of the vulva is formed
by a transverse, somewhat hollowed, ridge, which is gradually sloping forwards. In front of this, and on
each side are a median and an anterior laminous process, of which the latter is the longer and thinner; the
processes on the left side are comparatively shorter, and are placed more posteriorly; in ventral view they
are seen to be turned towards the middle, thus partly covering the vulva. The third and fourth somites
are almost smooth, and without any hairs below, in contrast to the fifth somite, which has ventrally a
tuft of hairs; it is dorsally almost completely covered by the preceding tergite. The subapical seta is
thinner but not very much longer than the St. 2, and it is not geniculated.

The antennulae extend almost to the tip of the anterior part; they are in the main like &. norv.,
but the segments 24 25-are just as long as segment 20, and 23 is a little longer than 16, which is as
long as 17. The antennae and mandibulae do not show any features of interest. The Lex of the max-
illulae bears 6 bristles of almost equal width basally, but the distal bristle is much shorter than the others,
which are much longer than the breadth of the maxillulae. The Li x has the usual ro hairs anteriorly,
but only two posteriorly; the Li II as well as Li III is well developed, and each bears a long seta. The
basipodite III has 3 setae with short. hairs, of which the distal is the longest. The RiI has 2 rather
slender and a single powerful seta, while the Ri II~III have 4 powerful ones. The convexity of the
exterior margin in the basal segment of the maxillac is just indicated (text-fig. 54d). The Aes Z has

184 COPEPODA

only the limitation between Re I—II indicated, where the muscle is fastened inwards; the articulation
between the Re II and III is well marked anteriorly, but only indistinctly so posteriorly (text-fig. 54 e).
The exterior border has a well marked concavity (as shown in Farran’s fig. 18 in contrast to Scott’s
fig. 15) and a long and slender Se 1, almost reaching the base of Se 2. The fes // is like the figures
of the two authors; the Se Re II scarcely reaches the end of the Se 1 Re III, and Se 2 Re III scarcely
reaches the end of Se 3.
The epistoma and the anterior surface of the /adrum are scarcely different from those of &. norz.
The oral surface of the /abrvwm (fig. 11 a)
shows a distinct difference from that of
E. norv., as is realised by comparing fig-
ures; the most characteristic feature is the
lateral position of the first group, in front
of which, behind the marginal fringe, a
granular area is found. The usual spinous
area behind the median spot Nr. 4 is
wanting. The lamina labialis is, as seen
in fig. 1rb, somewhat different from
£. norv., but more interesting is the large
lateral group of hairs almost completely
fused with the median group, situated in
front of the lamina. The lobus labialis has
the posterior lateral group well developed.
3. Size: 48 mm.; anterior division
(22 + 14) = 36 mm.; urosome 12 mm.
The body is rather clumsy, and about
3 times as long as the urosome; no dif-
ference was found between the lateral
corners on the right and left side, and

d f g j no tooth was observed. The genital so-
Text-fig. 54. Euchete bisiiuata G. O. Sars. mite is distinctly asymmetrical, as it is

a. £9. Abdomen 18. b—c. f9. Furca X 18 and 57. d. £9. Maxilla dext. produced behind on the right side. The
from behind X 57. e £9. Pes I X57. f. fo. Pes V in anterior view 3 2 ;
x75. g—h. yQ—d (St. V). Abdomen x 16. j. yo (St. V). Pes V X57. Stbapical seta is as usual in the male

short and thin.

The maxillulae are as a whole less developed than in the male of & zorv, and differ in minor
points, The LeI has, in addition to the 5 long setae, a delicate basal one, and the Basp. has only a
single seta. The Basp. II of the maxillipeds has in the lob IV only a single hair in addition to a
hooked clumsy organ surrounded by delicate hairs (fig. 11 c).

The fes J has no Se in the first segment, which is well separated from the second by a com-
plete articular membrane; the Se 2, which is short and strong, is placed on the somewhat produced
exterior corner of Re II. The es //7 has, in contrast to. the female, the Se Re II very short

COPEPODA 185,

and the Se 2 Re III does not reach the end of the segment. The pes V (fig. 54 f) resembles in most
respects that of &. zorv. The Ri dext. is long and slender, consisting of a single segment, but divided
into two, about equal, divisions (of which the posterior is the more slender) by an exterior rounded emi-
nence, which is indicated in Z glacialis. The ReIowII of the right leg, which is 15 as long as the
Re III, shows by an indistinct incision indication of subdivision into a basal and a terminal segment;
a small Se ReI is found. The Ri sin., which is short and club-shaped, shows trace of segmentation
only towards the tip, and has terminally a very minute spine. The tip of the left exopodite is, as seen
by comparing the figures (Pl. VI figs 11 d—e), like that of &. norv., but differs distinctly by the short
and clumsy form of the serrated interior lobe with two distal rows of larger and smaller teeth con-
verging towards the end, and by the comparatively long hairy appendage (text-fig. 54 f).

¥g (St. V). Size: 2 411 mm.; anterior division (2°09 + ror) = 3°1; urosome 1°Or mm.

In two female specimens the first abdominal somite is distinctly produced below, in a single
male scarcely so (text-figs 54 g—h). The measurements of the extennulae and the structure of pes I—II
are scarcely different from those of adult females. The pes V # does not provide features of great
interest (text-fig. 54 j).

YQ (St. IV). Size: 3:36 mm.; anterior division 2°5 mm.; posterior 086 mm. A single female, which
ought perhaps to be referred to this species, was examined.

Occurrence. The S/S Thor has taken ™/, rg04 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire
9 £9, 4£d, 2y? (V), 1 yd (V), ry? AV).

It has previously been recorded by Sars from several stations, from the Monaco Expedition, by
Farran “in small numbers at three stations” off the west coast of Ireland as far north as 55° N.
(10°45 W.) “at depths between 700 and and 1150 fathoms”, and by Scott, taken by the Siboga Exp.,
from 5 stations (I—2 specimens) in considerable depths.

Remarks. As the described males and females were found together, as they corresponded fairly
well to each other in size, and as I did not find any species to which the males are more naturally
referred, I have referred them to the same species, in spite of a rather curious difference found in the
structure of pes I. The young specimens, on account of rounded lateral corners, size and similar
structure of pes I—II, were referred to the same species.

In spite of minor differences from Sars’ and Scott’s descriptions, scarcely any doubt can exist,

that the specimens examined by the different authors belong to the same species.

56. Eucheete gracilis G. O. Sars.

(Text-fig. 55.)
1894. Euchzte barbata Brady. Th. Scott, p. 58, pl. VI fig. 17. I91t. Eucheete quadrata Farran. Wolfenden, pp. 297—298, fig.
1905. -— gracilis n. sp. G. O. Sars, p. 16. 39, Taf. XXXV fig. 1.
1908. — quadrata n. sp. Farran, p. 43, pl. III figs 20—2r.

Description. f£9. Size of specimen from St. 88 was 674 mm.; anterior division (2°76 -++ 1°96) =
472 mm.; urosome 2°02 mm. Sars’ specimens measured 66, Farran’s 69, Wolfenden’s 585—6 mm.
The shape of the body is practically like that of Z morvegica. The lateral corners are not

regularly rounded as stated by the authors, but somewhat squarely truncate (text-fig. 55). The genital
The Ingolf-Expedition. III. 4. 24

186 COPEPODA

somite, which is distinctly shorter than the following two, but 1°5 as long as the second, has a very
prominent and characteristic genital protuberance. The vulva is surrounded by a chitinous system
distinctly more complicated than figured by Wolfenden; more exteriorly, along the lower margin,
is found on each side a chitinous plate pointing forwards, which, somewhat in front of the middle, possesses
a short, rounded process (cf. Wolfenden). As stated by Wolfenden, in contrast to Sars and Farran,
hairs were found on the ventral surface in the third and fourth abdominal somites in most specimens.
The antennulae extend scarcely to the end of the thorax; the appendages are scarcely different
from those of Z. zorv., and the measurements are not very characteristic; the segment 20 is as long
as the segment 24™ 25, and the 23 as long as the 16. The antennae and mandibulae are scarcely dif-
ferent from those of & morv., while the maxzllulae, as pointed out by Farran, possess, in the Le 9
bristles, of which the 2 proximal are moderately short; the Basp. III has four setae and the three seg-
ments of Ri have three setae each. The maxillae and maxillipeds are like those of Z zorv., but the
latter differ by the more slender spines of Ri.

The articulation between the ReI and II of fes 7 is anteriorly indicated outwards, and posteri-
orly inwards; the Se Rel is represented by a small protuberance. The Se Re II
pes II extends almost to the tip of Se Re III, and the Se 2 extends just to the

base of Se 3.
The shape of the epistoma is scarcely different from that of &. xorv.
The anterior surface of the /aérum has. the hairs somewhat differently placed;
anteriorly, in the middle, a transverse row of short hairs is found, in addition to a
more lateral group of rather long setae; laterally and more posteriorly an area

Text-fig. 55. Zuchete covered with densely placed short spines is observed. The oral surface of the
gracilis G, O. Sars.

labrum and the labial lobes are scarcely different from £. zorv., and the area in
Abdomen X 16,

front of the damina labialis only differs by less regular lateral groups of hairs.
Occurrence. The Ingolf Expedition has not taken this species, but it has been gathered by
the Thor at the following stations.

"/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 £9.
15/6 1905 St.82 51°00 L. N. 11°43 L.W. Yt. 1200 M. Wire 3 f9.
8/6 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 1 f9.
20/, 1905 St. 88 48°09 L.N. 8°30 L.W. Yt. 300 M. Wire 5 f? (2 with sperm).
21/5 1905 St.9o0 47°47 L.N. 8°00 L.W. Yt. 300 M. Wire 2 f9.

This species “was taken in small numbers on five stations at from 350 to 700 fathoms” off the
west coast of Ireland. It has also been gathered by tlie Prince of Monaco and the Gauss at several
stations in the Mid-Atlantic.

Remarks. ‘This species is probably identical with Sars’ & gracilis, as no difference was found
between my specimens and Sars’ rather incomplete description. From A. Scott's description it differs by
the shorter antennulae and the hairy ventral surface of the abdominal somites III—IV. From Wolfenden’s
description of most of his specimens it differs by 9 instead of 7 setae in Le of the maxillulae, and by
the comparatively shorter Se 2 Re III pes II; as, however, one of Wolfenden’s specimens had compara-

2 ee eee ee ae ee Ce ee |

_— a (a a

COPEPODA 187

tively long antennulae and comparatively short Se2 there is reason to suggest that the value of these
characters ought not to be exaggerated.

57. Euchete acuta Giesbrecht.
(Pl. VI figs 12 a—e; text-figs 56.a—b.)

1892. Euchzete acuta n. sp. Giesbrecht, p. 246, Taf. 16 and 37. | 1905. Eucheete acuta Giesbr. Esterly, p. 157 fig. 23.

1898. — — Giesbr. Giesbrecht & Schmieil, p. 38. 1906. o — — Pearson, p. 17.

1903. a — — J. C. Thompson, p. 18. | 1908. - _ — Fearran, p. 4o.

1903. — _ — J.C. Thompson & A. Scott, p.244. | 1908. — _ — v. Bremen, p. 51, fig. 56.

1904. -- = Wolfenden, p. 111. 1909. a — — A. Scott, p. 65, pl. XX figs 1-9,
1904. _— _ — Cleve, p. 190. 1909. — — — Pesta, p. 23.

1905. o -- — G.O. Sars, p. 4. IgII. — = a Wolfenden, p. 299.

1905. _- _— — Farran, p. 35. IgI2. — a — Pesta, p. 22.

Description. £9. Size: 4:02 mm.; anterior division (1°7 +097) = 267 mm.; urosome 1°35 mm.
Giesbrecht’s specimen measured 41 mm., Farran’s 44mm. and Scott’s 4:2 mm.

The genital area has on each side of the vulva a lamina-shaped process, somewhat larger on
the right side; the outline is, as shown in fig. 12a, somewhat different from Giesbrecht’s fig. 47 (Taf. 37).
Scott’s fig. 4 of the abdomen in dorsal view differs distinctly by the presence
of a right lateral process (may possibly be the process on the right side of the
vulva, which is visible when the animal is not examined in complete dorsal
view). The subapical seta is much longer than the St. 2.

The antennulae, mouth-limbs and natatory limbs are scarcely different
from Giesbrecht’s description.

a b

The epistoma and the anterior surface of the /abvwm do not show any isatitle:'g6)y Riehl acute

features of interest. The hairs on the oral surface of the labrum show a rather Giesbr. Yo (St. V).

a. Abdomen x 18. b. Pes V

simple arrangement. The group 1 is, as usual, placed somewhat laterally, but it aahaste elas bud:

is not distinctly separated from the group 2; the groups 3—4 are small and well

marked out; the group 5 is fairly big. The transverse row behind the median spot Nr. 3 is short and
narrow. No lateral group was observed (cf. fig. 12b). The lateral group in front of the damina labialis
(fig. 12 c) consists of small granules, and is well separated from the median groups; these consist, as

shown in fig., of fairly long hairs; the inner group of granules anteriorly was not observed.

Yo (St. V). Size: 3°72 mm.; anterior division 2°68 mm.; urosome 1°04 mm.

The lateral corners are rounded. The subapical setae are, as in the adult females, stronger as
well as much longer than the St. 2. The awtennulae extend scarcely to the end of the anterior division.
The appendages are scarcely different. The structure of the /#/¢h foot is seen in text-figs 56a—b.

Occurrence. ‘The species was not gathered by the Ingolf Exp.; but, as it was found by the Thor ~
at the following 3 stations, I have included it here.

5/6 1905 St. 82 51°32 L. N. 11°43 L. W. Yt. 1200 M. Wire 1 £9.
20/6 1905 St. 88 48°09 L. N. 8°30 L.W. Yt. 300 M. Wire 15 f9+ 1 yo.
2t/, 1905 St.90 47°47 L.N. 8°00 L.W. Yt. 300 M. Wire 1 f9?.

24*

188 COPEPODA

Distribution. This species has been taken off the west coast of Ireland, in the Mediterranean,
in the South Atlantic as far south as 25° L. S., in the Indian ocean, and in the Pacific.

58. Euchzte hebes Giesbrecht.
(Pl VI figs 13 a—b; text-fig. 57.)

1888. Euchzete hebes n. sp. Giesbrecht, p. 337. 1905. Eucheete hebes Giesbr. G. O. Sars, p. 4.

1892. — — Giesbr. Giesbrecht, p. 246, Taf. 15 and 37 | 1906. _ _ — Norman & Scott, p. 128.
figs 15—16. 1908, — _ — vy. Bremen, pp. 51—52 fig. 57.

1894. ? _ — — Th, Scott, p. 59, pl. VI figs 18—19. | 1909. — — — . Pesta, p. 24.

1898. _— “= _ Giesbrecht & Schmeil, p. 39. IgI0. — — — Steuer, p. 24.

1903. - _ — Lo Bianco. IgII. — — — Farran, pp. 94—95.

1905. — — Gough, p. 336, figs 4—7. IgI2. — — — Pesta, p. 22.

Description. £9. Size: 354 mm.; anterior division (1°56 + 0°99) = 2°55 mm.; urosome o'99 mm,
Giesbrecht’s specimens measured 2°85—2'95 mm.

Near the lateral margin of the last thoracic somite is found, dorsally, a membranous fringe bearing

short hairs; it is not equally prominent in all specimens, but generally more so than shown in fig.13a. The

abdominal somite I~ II has, dorsally, a characteristic process, and, on each side of the

vulva lamelli-form processes more developed, on the right side. One of the 6 apical setae

(] of the maxillae shows the structure characteristic of Pareuchete with several short

teeth and a few larger branches. The number of glandular pores in the legs scarcely

Text-fig. 57.
bee nth differs from those of &. morv., except by the absence of any pore at the base of Ser Re III.
Yo (St. V). Pes V The epistoma and the outer surface of the /advwm are in main features like
X 39

those of & zorv. The oral surface has the two first groups placed rather longitudinally,
and the three following ones fairly well separated. The area in front of the /amina labzalis is, as shown
in fig. 13 b, rather characteristic, especially by the lateral group of hairs, which is a longitudinal series
in continuation of the serrula 6-dentata.

&. Size: 3:03 mm.; anterior division (1°35 + 0°78) = 2°13 mm.; urosome og mm. Giesbrecht’s
specimens measured 2°75 mm.

Lateral corners are rounded and somewhat more produced on the right than on the left side;
on both sides is, dorsally, the usual fairly well developed tooth. The first abdominal somite has on each
side, dorsally, a similar tooth as in Z. xorv. The antennulae reach distinctly beyond the end of the
cephalo-thorax; the segments 12—13 are, posteriorly, indistinctly separated, and more so on the left side.

The Rel of ses V has a fairly well developed Se.

3 (St. V). Size: 268 mm.; anterior division (1°19 +075) = 1°94; urosome 0°74 mm.

The lateral corners of the thorax are regularly rounded without the mentioned hairy fringe.
. The subapical seta of the furca is only a little longer than the St. 2. Pes V differs from £. morv. by a
more rounded Ri sin.; the outlines of the exopodites are, as realised by comparing text-figs 471 and
57, somewhat different.

Occurrence. Within the area explored by the Ingolf Exp. this species has not been taken; but,
as it has been gathered by the S/S Thor 2"/6 05 St. 90 47°47 L. N. 8°00 L. W. (viz: 23 £2 (2 with egg-
sacs), 2 fd, 1 yd (V)), I have included it here. As the species has only been found in the Mediterranean

COPEPODA I 89

and the East Atlantic, especially with moderate frequency off the mouth of the English Channel, and
as it has not been recorded by Farran from the west coast of Ireland, Farran is probably right in
regarding it as a member of the Mediterranean fauna in its wider sense (cf. p. 95).

Scolecithricidae.

59. Scaphocalanus magnus Th. Scott. _
(Pl. VII figs 8a—d; Pl. VIII figs 6a—g; text-figs 58 a—k.)

1893. Amallophora magna n. sp, Th. Scott, p. 55, pl-VI figs 5—9. | 1905. Amallopbora magna Scott. G. O. Sars, p. 5.
1894. Scolecithrix cristata n. sp. Giesbrecht, pp. 252, Taf.II—III. | 1905. Scolecithrix cristata Giesbr. Farran, p. 36.
1898. _ —- Giesbr., Giesbrecht & Schmeil, p. 48. | 1906. -- magna Scott. Esterly, p. 66, pls 9, 11—13.
1g00. Scaphocalanus acrocephalus 1. sp., G. O. Sars, p. 36, pls | 1906. Amallophora — — Pearson, p. 17.
VII-IX. 1907. — -— — Koefoed & Damas, p. 410.
1903. Amallophora magna Scott. G. O. Sars, pp. 51—53, pls | 1908. Scolecithrix — — Farran, pp. 51—52.
4 XXXIV—XXXV. 1908. — a — v. Bremen, p. 76 fig. 89.
1903. Q nec. d Scolecithrix cristata Giesbr., J. C. Thompson, | 1909. Scaphocalanus magnus Th. Scott. A. Scott, p. 97.
p- 21. 1911. Amallophora magna Scott. Wolfenden, p. 262.
1904. Amallophora magna Scott. Wolfenden, p. 111. 1913. -- _ — Stephensen, pp. 313—314.

Description. £9. Size of specimen from Thor St. 183 was 5:23 mm.; anterior division 4:08 mm. ;
urosome 1°15 mm. Sars’ specimens measured 5 mm., Giesbrect’s and Scott’s 4'5 and Wolfenden’s
37 to 4:25 mm.

The lateral corners of the thorax are triangularly produced and more or less rounded; but the
shape is, however, as seen in text-figs 58 a—i, rather variable, and in some specimens rather suddenly
produced. The third basipodite of the mandibudlae is less elongate than figured by Sars, and has two,
not one, setae interiorly; the first inner segment has two terminal setae, and the second has nine. The
maxtllulae are scarcely different from Sars’ figure; the third basipodite has five setae as shown in
Giesbrecht’s fig. 1 Pl. III, not 4 as mentioned in the text. The Lir bears to setae anteriorly and 3
posteriorly. The maxdllae and maxillipeds scarcely differ from Sars’ figures.

The second pair of legs shows a few features not mentioned in Sars’ description. On the anterior
surface of the three outer as well as of the three inner segments groups of short teeth are observed;
the first inner segment has, as seen in fig. 8b, a small outer tooth, which was, however, wanting in
another specimen. The first outer segment shows also a few spines on the posterior surface. The an-
terior surface of the third as well as the fourth foot is, as mentioned by Giesbrecht, covered all over
with small teeth. The marginal setae of the second basipodite in the fourth pair of legs are poorly
developed or wanting.. Glandular pores were not observed, except one in the outer margin of the third
outer segment of the first pair of legs. The “7h pair of legs is in most specimens like that figured
by Sars, but it is often rather asymmetrical, and the outer seta extends sometimes beyond the end of
the segment, and is sometimes much shorter.

The elevation in front of the labrum, corresponding to the antennal segment, is slightly raised
(Pl. VII fig. 8a); the labrum proper, which is produced in front as a rounded protuberance; is by an

190 COPEPODA

anteriorly convex line divided into an anterior and a posterior smaller part; the labrum proper is beset
with a number of shorter and longer bristles, the somewhat complicated arrangement of which is most
easily understood by studying fig. 8c —

The oral surface of the /abvwm (Pl. VII fig. 8d) shows a rather characteristic structure; the
longitudinal series on each side consists anteriorly of an oblique group of fairly long and strong spines;
behind this two or three groups of comparatively long and slender setae are found, followed by a more
medially placed, almost square, area of short spines; behind the last mentioned group, which is only
separated from the corresponding one of the other side by a narrow smooth area, an oblique one covered

: with delicate hairs is found. The Jamina labialis seems to be represented by a very short transverse

plate; in front of it and the serrula 6-dentata a medial short row of fairly long
setae and a longer curved lateral one of shorter setae are found. Behind the
lamina labialis and between the serrulae is found on each side a short group

ed hairs behind, as well as upon, the labial lobes consists, as in \S. ovatus (fig. 14 b)
f

placed scattered setae.
8 £3. Size of specimen from Thor St. 214 was 4°74 mm.; anterior divi-
i sion 314 mm.; urosome 16 mm. Sars’ specimens measured 4°5 mm.
j
k

Hows: The fifth thoracic somite is well marked out, and its lateral corner is
See rounded. The comparative length of the abdominal somites and the furcal

of strong spines, almost fused with the corresponding one of the other side, as
well as a more posterior and lateral group. The arrangement of the delicate

of a median and, on each side, a lateral group, in addition to more laterally

rami is 15, 83, 47, 52, 10 and 20.
The antennulae extend somewhat beyond the end of the thorax, and
are distinctly attenuated towards the end; they are proximally to segment 14
Text-fig. 58. slightly curved, and the proximal portion forms an obtuse angle with the

Scaphocalanus magnus T. Scott.

; : more attenuated distal portion. The segments 8~ 9 are completely fused with
a—i. Left lateral corner in 8

different adult females X59. segments 10—12; the segment 13 is well separated, and the segments 21—21
j—k. Same of two young males

(St. V) X 59. generally so. “Aisthetasken” are beyond segments 8&9 only observed in seg-

ments 12, 14, 15, 16 and 25. The antennae have comparatively long setae,
and the second outer segment is distinctly restricted in the middle. The manducatory part of the
mandibulae is more soft-skinned than in the female, and has less powerful teeth; the third basipodite
is much wider than in the female, almost as wide as long, and has the inner setae short and delicate.
The maxillulae are more elongated, and their setae are less powerful than in the female; the Li II has
only a single seta, the Basp. III has only 4, and the RilI has 2 for 3. The maxillae are in general
shape like those of the females, but their appendages are less developed. The maxzllipeds are as figured
by Sars, but are more slender and delicate.
The natatory legs are scarcely different from those of the female.
The th pair of legs is scarcely different from Sars’ figure; the terminal attenuated part of
the right endopodite is articulated, and corresponds to the third segment,

COPEPODA I9I

¥g (St. V). Size of male from Thor St. 183 was 3°94 mm.; anterior division 3:04 mm.; urosome
o790 mm. Another specimen measured 4°12 mm.

The shape of the body is in the main like that of the adult females, but the articular line be-
tween the head and the first thoracic tergite is fairly distinct; the fifth thoracic somite is well marked in
front with produced pointed lateral corners directed somewhat downwards (text-figs 58 j—k; PI.VIII fig. 6f).

The antennulae almost reach the end of the body; the other appendages are scarcely different
from those of the adult female; the spinulation of the anterior surface of the natatory legs is well
developed.

The only difference between the sexes is found in the fifth pair of legs, which in the male has
2 fairly elongated basal segments and a two-segmented exopodite in addition to a somewhat shorter
endopodite (Pl. VIII fig. 6 g).

Variation. In an adult female from Thor St. 183, which had the lateral corner of the thorax
produced as in text-fig. 58g, but in no other respects differed from the described specimens, the fifth
pair of legs was distinctly asymmetrical with a rudimentary endopodite (Pl. VIII fig. 6c); in another
female (Nr. 2) with the same shape of the lateral corner, the pes V was symmetrical and like the right
leg in Nr. 1, but with strong inner seta and rudimentary outer one; in a third specimen, like the
others from St. 183 (Nr. 3), a fairly well developed endopodite was found, and two Se were present in
the exopodite; in a fourth specimen from Thor St. 152 (Nr. 4) with the lateral corner like text-fig. 58 b,
the third outer segment has two terminal setae, but no endopodite was found. The pes IV in an ab-
normal specimen is seen in fig. 6b (Pl. VII).

Occurrence. The Ingolf Expedition has not gathered any specimen of this species, probably
because it prefers the deeper strata, at least in the northern regions; by the Thor it has been gathered
at a good many localities. It is rather curious, that the young males of the penultimate stage are much
more common than the young females; of the examined 34 young specimens only 5 were females.

In Denmark Strait:

19/6 1904 St. 152 65°00 L. N. 28°10 L. W. Yt. M. Wire 18 £9, 3 yo (V).

vik tail eta Vee 2yd (V).
41/6 1904 St. 154 65°27 L. N. 27°10 L. W. Yt.? rig.
20/6 1904 St. 150 65°50 L. N. 20°53 L.W. Yt.? 12 £9 (1 sp), ryd.

South. of Iceland the species was taken at 3 stations viz:
/, 1904 St. 285 62°49 L. N. 18°46 L. W. Yt. 500 M. Wire 6f9, 2y?, 6 yc.
™/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt..1800 M. Wire 28 £2 with rounded lateral corner, 15 f?
with lateral corner more or less produced and 3f9 with Ri pes V, 1 fo, 2 y? (V), 11 yo (V).
24/, 1904 St. 104 62°47 L. N.-15°03 L. W. Yt. 1500. M. Wire 25 £9, ryd.-
In the Iceland—Feeroe channel it was taken at 4 stations viz:
9/5 1905 St. 165 60°00 L. N. 10°35 L.W. Yt. tooo M. Wire 1 F9.
tl, 1905 St. 167 57°47 L.N. 11°33 L. W. Yt. 1500 M. Wire 27 £9, ry2, 2yd.
9/; 1904 St.70 63°32 L.N. 6°20 L. W. Yt. 100 M. Wire 1 f9.
23/, 1905 St. 124 61°04 LN. 4°33 L.W. Yt. 1000 M. Wire 2 f9.

192 COPEPODA

North-east of Iceland:
22/, 1904 St. 214 67°19 L. N. 17°55 L. W. Yt. 800 M. Wire 19 f9, rid’, 1 yo (V).
Outside the Ingolf area the species was captured:

5/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 800 M. Wire 119, 1 yh (V).

Yt. 1200 M. Wire 4 £9, 4 yo (V).
3/6 1905 St. 72 57°47 L. N. 11°33 L.W. Yt. 1500 M. Wire 35 £9, rf, 2 y?, 10 yd.
20/, 1905 St. 88 48°09 L. N. 8°30 L.W. Yt. 300 M. Wire 1 f9.

Distribution. This species seems to have a world-wide distribution; it has been found, though
rather scarce, generally in considerable depths in the Antarctic seas (65° S. 85° E.), in the Atlantic, south
as well as north, even at the Equator (c. 30° L. W.), in the Arctic seas, in the Malay Archipelago, in the
Gulf of California between 50 and 300 fathoms (Esterly 1912, p. 321) and in the Pacific (35° L. N. 125°
L. W. o—300 m.). According to Farran (p. 52) it is “a very common and noticeable species in deep
water” off the west coast of Ireland, “it occurred on every station and in almost every tow-netting be-
tween 280 and 1150 fathoms”. The species was sometimes found in the Norwegian Sea between 200
and 1000 metres as well as in the deep Norwegian fjords. By the Duc d’Orléans it was taken at eleven
stations (in about 15 samples) in the ocean east of Greenland between about 200 and 1800 metres; it
is rather curious that it was never found farther east than 9°00 L. W. at 75°55 L. N.; it was found
near the coast of Greenland and as far north as 78°13 L.N. It was found as far south as 71°22 L. N.
(18°58 L. W.); only in a single sample St. 43 '/s 1905 78°13 L. N. 16°31 between 310—475 meters was it
found fairly common, males as well as females. By the Nansen’s Expedition it was found fairly,
abundant, sometimes up to the very surface of the sea as far north as 84° L. N. between 134 and 76
Long. E. These different facts indicate, as pointed out by Sars, that this form has its main area of
distribution in the Polar basin, though it is found in small numbers in the deeper layers of the dif-
ferent seas.

Remarks. As the variations in the lateral corners, as well as in the fifth pair of legs in the
females, are rather common, I did not find any reason to establish a new species for the three men-
tioned specimens with a well developed endopodite. The features which distinguish my specimens
from Giesbrecht’s Sc. cristata are enumerated above, and are too unimportant for establishing two
species. Wolfenden’s specimens from the Atlantic measured 3'7, and those from the Antarctic seas
425 mm., but he could not find any other characters, except in the comparative length of the spines
of the fifth pair of legs, which, as shown above, are very variable.

60. Scaphocalanus brevicornis G. O. Sars.
(Pl. VII figs 7 a—b; textfigs 59 a—b).

1900. Scolecithrix brevicornis n. sp. G. O. Sars, pp. 46—47, pl. X. | 1907. Amallophora brevicornis G. O. Sars. Damas & Koefoed,

1902? — — G. O. Sars. Th. Scott, p. 452, pl. p. 410.
XXV figs 1—2. 1908. Scolecithrix gracilipes n.sp. Farran, pp. 52—53, pl. VI

1903. Amallophora brevicornis G. O. Sars. G. O. Sars, pp. 53—54s figs I—4.
pl. XXXVL 1908. _ brevicornis G.O. Sars. v. Bremen, p. 78, fig. go.
1904? _— — ao Wolfenden, p. 137. 1913. Amallophora brevicornis G. O. Sars. Stephensen, p. 314.

i
ST ae a ee

COPEPODA 19 3

Description. {9. Size of specimens from Ingolf St. 105 was 2:23 mm; anterior division 1°66 mm.;
urosome 0°57 mm. Sars’ specimen measured scarcely 2 mm.; Farran’s 2°3—2°5 mm.

The shape of the body is scarcely different from Sars’ figures; the appendages, as far as they
were examined in the single mutilated specimen, were scarcely different; posteriorly, near the end of the
second outer segment of the first pair of legs, a transverse row of short spines was found. The //¢h
pair of legs has on the left side the Se standing opposite the Si, as in Sars’ figure, but on the right
side it stands somewhat more distally.

fg. Size of specimen from St. 82 Thor was 2‘5 mm.; anterior division 1°65 mm.; urosome 0°85 mm.
A male from St. 183 measured 33 mm.

The shape of the body is rather slender, very much like that of 8. magnus. The distinction
between the head and first tergite is indicated dorsally, and the fifth thoracic tergite, which is rounded,
is well marked out. The.vos/rwm consists of a basal bifurcate part, which
is prolonged into a thin rather stiff filament on each side; the outline
is, above the rostrum, at least in the single, somewhat mutilated specimen,
somewhat concave. The abdomen (fig. 7 a) is distinctly half as long as the
anterior division, and the comparative length of the somites is 7, 435275
30, 4, and ro for the furca, which is about 13 as long as wide.

The antennulac, which were broken, have the proximal segments
like those of S. magnus. The antennae are scarcely different from those of
the female. The manducatory part of the mandzbulac is rather slender; the
third basipodite is very short and robust; it possesses, somewhat beyond
the middle, a single short hair and, more terminally, at least one quite rudi-

mentary one. The maxillulae are well developed and in most respects like

those of the female. The long well developed Li I has ro short setae at

least, the Li II has one, the Li III has 3 at least, and the third basipodite 4
3 f Text-fig. 59. Scaphocalanus bre-

has 5; the Ri I has 2, and the Ri III~II have 5 setae; the exopodite sscornis-G; O, Sars. Ect.

a. Pes V dext c..150, b. Pes

. ; V in situ from the left; termi-

respects like those of the preceding species. nal segments X c. 250.

has 7 well developed setae. The maxillae and mazxillipeds are in most

The xatatory legs were scarcely different from those of the female;
on the posterior surface of the third outer segment in the first pair of legs no spines were observed.
The fifth pair of legs (fig. 7b and text-fig. 59b) is in the main like those of the preceding species,
but differs, however, in a few respects. The inner terminal process of the first outer segment of the
right foot is somewhat pointed, not rounded; the right endopodite has the two first segments some-
what convex with a small inner terminal process, which was not observed in the bigger specimen; the
terminal segment is better articulated. The left right leg is scarcely different from that of the preceding
species except in minor details, as seen when comparing figures (text-fig. 59 b); the left Re III has 3
fairly long setae. ia

Occurrence. The Ingolf Expedition has gathered a single mutilated female with closing net
700 fathoms '"/, 1896 St. 105 65°34 L. N. 7°31 L. W.

The S/S Thor has gathered a single male:

The Ingolf-Expedition. IIT. 4. 25

194 COPEPODA

1t/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire.
"5/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 1200 M. Wire.

Distribution. ‘This species has been found at a single station in the Polar basin at about
84" L. N. and go° L. E. In the sea between Spitzbergen and Greenland the Duc d’Orléans has between
™2/, and 5/s gathered it at 4 stations, and sometimes in considerable numbers, males as well as
young ones, f. inst. at St. 43 78°13 L. N. 16°31 L. W. 310—475 meters depth; the three other localities
were at 79°39 L. N. 2°40 L. E. 1200--1800 Meters depth, at 78°05 L. N. 5°21 L. W. 500—1350 M. depth,
and 71°22 L. N. 18°58 L. W. It has once been recorded from the Norwegian Sea in a depth of about
400 M., and from the west coast of Ireland at a depth lying between 280 and 680 fathoms, and always
rather scarce.

Remarks. Though the males and the female were found at widely separated localities, I am
fairly convinced that they belong to the same species, and without doubt to S. dvevicornis. As the male
described by Scott is only 15 mm., and as the fifth pair of legs seems to differ in several respects,
I am not convinced that it ought to be referred to this species.

I am fairly convinced that Farran’s species .S. gracilipes, which was established with due
reservation especially on account of “the more distal position occupied by the outer-edge tooth of the
second joint of the fifth foot,” is identical with this. Farran has (p. 53) found a rudimentary endopodite,
like that observed in specimens of S. magnus (cf. p. 191) in a specimen of his Scolecithrix gracilipes as
well as of his S valida, which he regards as an anormality. In this, as well as in his opinion of

Giesbrecht’s genus Racovitzanus, I agree with him (cf. Wolfenden tg1r p. 259).

61. Scaphocalanus obtusifrons G. O. Sars.
(Pl. VII figs ga—d; Pl. VIII figs 8a—e; text-figs 60a—c and 61 a—d).

1905. Amallophora obtusifrons n. sp. G. O. Sars, p. 22. | 1908. Scolecithrix obtusifrons G. O. Sars. v. Bremen, p. 25, fig. 87.
1905. Scolecithrix emarginata n. sp. Farran, pp. 36—37, pl. VII | 1909. Scolecithricella obtusifrons G. O. Sars. A. Scott, p. 92, pl.

figs 6-17. | XXXI figs 1-9.
1906. Amallophora obtusifrons G. O. Sars. Pearson, p. 17. | 1911? Scolecithrix cequalis n. sp. Wolfenden, pp. 255 —256, text-
1906? Scolecithrix inornata n. sp. Esterly, p. 67, pls 9, 11 and 13. | fig. 33.

1908. Scolecithrix obtusifrons G. O. Sars. Farran, p. 54.

Description. £9. Size of specimen from Thor St. 72 was 4'4 mm.; anterior division 3°55; uro-
some o5 mm. Sars’ specimens measured 56 mm., Farran’s 4:3 mm. and Scott’s 4°55 mm.

The shape of the body ete. is scarcely different from Farran’s description; each filament of
the rostrum is as stated by Sars and Scott terminally bifurcate (text-fig. 59a). The genital somite
is slightly produced below, and has a well developed curved receptaculum (PI. VIII fig. 8a).

The antennules, which extend a little beyond the end of the furca, are in measurement almost
exactly like Farran’s figures; the segments 24 and 25 are fairly well separated, the proximal seta is
wanting in segm. 10 as well as in 17, and the Sp. of segment 24, which is placed near the tip, extends only
slightly beyond the end of segment 25. The exopodite is distinctly longer than the endopodite of the
antennae, and this has 7 setae in the Li of the second segment and 5 setae in the Le. The mandi-
bulae are scarcely different from those of S. magnus, The maxillulae are like Farran’s figure, with 8

setae in the exopodite and 7 long setae and a shorter more delicate one in Le. The maxzllae have the

COPEPODA 195

exterior margin distinctly produced, and have, in addition to powerful vermiform sensory appendages,
at least 5 amalliform or brush-shaped ones. The maxillipeds are like those of S. magnus, and have,
in contrast to Farran’s, a sensory seta in the middle of the second basipodite.

The frst pair of legs has, as stated by Farran (fig. 14 Pl. VII), a well developed Se in Re I,
attaining the middle of Re II. The second pair of legs is in main features like Farran’s fig. 15 (cf. text-
fig. 60 b), but the outer marginal tooth of the second basipodite is well developed, and the inner margin
is near the tip produced into a short curved tooth; the arrangement of the spines on the posterior surface
differs only in minor details, f. inst. by the presence of spines in Re I, but in addition to the spines
areas of short teeth were found on the posterior surface of the exopodite; the anterior surface seems
to be smooth; the first inner segment has a well developed Se; the St of the third outer segment has
about 70 partly fused teeth (fig. 9a) without the characteristic basal fenestra. Glandular pores seem
to be present in Re II and III. The ¢hird pair of legs has the inner margin of the second basipodite,
a little proximally to the Si, produced into a longer or shorter, generally broken, styliform process,
corresponding to that of the second pair of legs; this process is beset inwards as well as terminally by
the most distally placed marginal bristles, and in this way
forms a prolongation of the inner margin proper; the
third basipodite is anteriorly and terminally produced into
a distinct slender spine medial to the insertion of the endo-
podite (text-fig. 60c), like that of Scotfocalanus. On the anterior

surface of the third feet, except in the third outer segments, ff

a delicate spinulation is found; the spinulation of the ° f \ .

Text-fig. 60. Scaphocalanus obtusifrons G. O. Sars £9.
: Ss a. Head X 33. b. Pes II sin in ant. view x 58.
group is found in the third outer segment. The /owrth c. Pes IV sin in ant. view X 58.

posterior surface is like Farran’s description, but a basal

pair of legs (text-fig. 60c) has the second basipodite very
clumsy without marginal bristles, and is suddenly restricted near the tip; on the posterior surface trans-
versely placed short spines were observed in Ri II, and in a less degree in Ri III, but the anterior
surface is covered all over with areas of more or less delicate teeth; the serrations of the terminal
setae are more or less fused in the middle; a glandular pore is observed not only in Re II and III,
but in Re I as well. The f/¢h pair of legs has the exopodite divided into a short basal and a longer,
somewhat enlarged outer segment, possessing a shorter terminal and a longer more proximal seta.
The anterior portion of the /abrum proper is distinctly more produced in front than seen in
fig. 8a of S. magnus; the arrangement of the setae is, as seen in fig. 9b, rather characteristic; the an-
terior curved group of long delicate setae is posteriorly on each side divided into an outer and inner
portion; in the middle an anteriorly convex row is found; for further details I refer to the figure.
The oral surface of the labrum (PI. VII fig. ge) shows a rather characteristic structure, bearing most
resemblance to that of Scottocalanus; the first oblique group of the longitudinal series is smaller than
in S. magnus, and it is followed by two or three more or less fused groups of fairly long setae, between
which the transverse median rows are placed, behind the mentioned groups an oblique one of more
slender hairs, corresponding to the square one of S. magnus is found. Laterally, in front, two groups of

delicate hairs are found. No distinct damina labialis was observed; in front of the serrula 6-dentata an
25*

196 COPEPODA

inner and an outer longitudinal series were found (Pl. VII fig. 9d); the arrangement of hairs between
and behind the serrulae was not studied in details. In the middle, between the labial lobes, a large
median group of setae was found, which on each lobe is continued into two lateral series placed
closely to each other; more laterally, well separated from this system, a lateral row of shorter setae,
starting from a basal group, was observed.

The intestinal tract is anteriorly produced into a rather slender rostral coecal sac; posteriorly
the wide stomach is attenuated, and is, somewhat in front of the abdomen, continued through a slight
curvature into the straight intestine proper. .

£3. Size of specimen from Thor St. 180 was 3°84 mm.; anterior division 2°65; urosome I'1g mm.

The body is somewhat more slender than in the female, with rounded lateral corners of the
well marked short fifth somite; the rostral filaments are scarcely different. ‘The wrosome is almost half
as long as the anterior division, and the comparative
length of its somites is 23, 40, 34, 44 and 4 (Pl. VIII
fig. 8c).

The antennulae scarcely extend to the end of

c i
the furca; the number of free segments is scarcely
different from that found in S. magnus, but the seg-

ments 13 and 15 are partly fused with the preceding
ones, as the articular line is wanting behind; the

measurements and the appendages are very much

like those of .S. globiceps. The antennae and mandi-
bulae are scarcely different from those of S. magnus.

Text-fig. 61. Scaphocalanus obtusifrons G. O. Sars fo. 7 i
a. Pes V X58. b. Pes V dext. Ri X 150. c PesV The maxtllulae are fairly well developed; the Le

saad Sli secs ee Si ic sg possesses g setae; the LiI has at least 8 rather
delicate setae, the Li II has 2 setae and the Li III has 4 setae; the third basipodite has 4 setae; and
the Ri 2-+5 setae; the exopodite has as in the female 8 setae. The maxillae are fairly developed,
with 4 setae in each of the four proximal lobes; the lobe V has one spine somewhat stronger than
the corresponding one of the lobe IV; the endopodite has 6 soft sensory setae, but not amalliform ones,
the maxillipeds are like those of the male of S. magnus, but no setae were observed in the middle of
the second basipodite.

The natatory legs show in all features of interest complete similarity to those of the female.

The 7th pair of legs is very characteristic, as seen in text-fig. 61a; on the right side (Pl. VIII
fig. 8c) we have a long and slender first basal segment, followed by a well enlarged second segment.
The right endopodite (text-fig. 61 b) is rather short, somewhat clavate, and has a slender, delicate seta
almost half as long as the segment; the right exopodite consists of three long slender ones, of which the
first is much the longer and thicker, while the third, somewhat plate-shaped one, is the shortest and
most slender (text-fig. 61c). The two basal segments on the left side are, like those of .S. magnus, long
and slender; the left exopodite has 3 segments (text-fig. 61 d), of which the third one, which is much
the shortest, is distinctly attenuated, with a terminal seta; the left endopodite is long and slender
and extends distinctly beyond the end of the exopodite.

COPEPODA 197

¥S (St. V). Size of specimen (male as well as female) from Thor St. 152 was 3°65 mm.; anterior
division 2°96 mm.; urosome 069 min.

The abdomen has four somites, but in other respects scarcely any difference was observed from
the adult females, except by the better developed articulation of the exopodite of the fifth pair of legs
in the females (fig. 8e). The fifth pair of legs of the males is clumsy, and most similar to that of
Scottocalanus, but has the setae better developed (fig. 8d Pl. VIII).

Occurrence. The Ingolf Expedition has not gathered this species, but the S/S Thor has brought
it home from several localities.

In Denmark Strait it was found:

21/6 1904 St. 154 65°27 L. N. 27°10 L. W. 3 £9.
9/6 1904 St. 152 65°00 I. N. 28°10 L. W. Yt. 1000 M. Wire 12 f9, 1 y? (V), 3 yo (V).

In the Atlantic, south of Iceland:

ly 1904 St. 285 62°49 L. N. 18°46 L.W. Yt. 500 M. Wire 1 y@ (V).

t0/, 1904 St. 180 61°34 L. N. 19°05 L.W. Yt. 1800 M. Wire 1 f9, rfc,

1/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800°M. Wire 7 £9, 1 fot, 2 y? (V), 2 yo (V).
24/; 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 15300 M. Wire 10f9, 1 yo (V).

In the Iceland-Feeroe channel:

29/3 1904 St. 165 60°00 L. N. 10°35 lL. W. Yt. 1000 M. Wire 1 £92.

22/; 1904 St.99 61°05 L.N. 9°35 L.W. Yt. 1700 M. Wire 2£9, 6f¢.

Tl, 1905 St. 167 57°46 L.N. 9°55 L.W. Yt. 1500 M. Wire 15 f9, 1 y? (V), 1 yo (V).
8/6 1905 St.72 57°47 L. N. 11°33 L.W. Yt. 1500 M. Wire 14 £9, 5 yd (V).

Distribution. “This species is a noticeable feature of the deep water plankton off the west coast
of Ireland” “at depths of from 330 to 1150 fathoms” {Farran); it has been taken by the Monaco Ex-
pedition as well as in the Malay Archipelago.

Remarks. That this species is identical with Farran’s Sc. emarginata is scarcely doubtful; Far-
ran’s specimens were identified by Sars with his A. odtusifrons, which is, however, distinctly bigger
and has the fifth feet somewhat different “muni en dedans d’une épine assez forte et allongée, et en
autre de 2 petits denticules, l'un apical, autre sortant du bord extérieur”. It differs from Scott’s de-
scription by the wanting delicate spinulation of the posterior surface of the fourth exopodite.

This species is nearly related to, if not identical with, Wolfenden’s S. aegualis from the South
Atlantic (1911, p. 255), as well as with .S. zzornata Esterly (1906, p. 67), but the descriptions are too insuf-
ficient for solving the question.

The species is characterised by the robust shape of the body and the antennulae, which are longer
than the body, without Spr. in segment 17, and without setae in segment 10. The Se ReI pes I is
comparatively short, and only attairis the middle of the following segment, while the Se Ri I pes II is
long and pointed. The St. Re III pes II has about 70 partly fused teeth. The inner terminal seta of
the anterior surface of Basp. III—IV is well developed, long and slender. The second basipodite of the

third pair of legs has a distinct lateral tooth, but no spinous lamina.

198 COPEPODA

62. Scaphocalanus validus Farran.
(Pl. VII figs 11a—b; text-figs 62 a—f.)

1908. Scolecithrix valida n. sp. Farran, pp. 55—57, pl. V figs 14—15, pl. VI fig. 7.

Description. f£9. Size of specimen from Thor St. 183 was 3°95 mm.; anterior division 3:1 mm.;
urosome 085 mm. Farran’s specimens measured 3°8—395 mm.

The body is more slender, and the head less suddenly raised in lateral view than in .S. obtus7-
/rons, but more distinctly so than in .S. globiceps (text-figs 62a—b). The rostrum is most like that of
the former species, with the basal part less enlarged and with fairly long, apparently undivided, filaments.
The lateral corners are slightly produced and rounded (text-fig. 62). The genital somite is better produced
below, and its receptaculum seminis appears more slender than in the preceding species; the comparative

length between the abdominal somites and the furcal rami is

aN 45, 28, 25, 9 and 17; the furcal rami are 1°5 as long as wide;
f along the hinder border of somites II—IV a marginal seam
s a with delicate serrations is observed.
i f

The antennulae do not reach the end of the furca; the
segments 24—25 are fairly well separated; “A{sthetasken” are
found in segments 809, 12, 14 and 19; the segment 10 has a
distinct seta, and a proximal seta is found in segments 12—14

18, and sometimes in segment 15, but never in segment 17;

the Sp. of segment 24 is somewhat longer than segment 25.

The segment 19 is distinctly 12 as long as segments 8%9
Text-fig. 62. Scaphocalanus validus Farr. £9.
a. Head X 33. b. Rostrum from the right x 59.
c. Genital somite 33. d. Pes II sin. in anterior aS long as 15. The third basipodite of the mandzbulae seems
view < 59. e. Pes III sin. x 59. f. St. pes II
sin. X 150.

and 15, which are of almost equal length; segment 16 is 1-2

to have only 2 setae medially; in other respects the mandi-

bulae as well as the antennae are like those of the preceding

species. The maxiilulae have 7 +-2 setae in the Le, 10-++2 in the Lil, 2 in Li lJ, 4 in Lilll and 5 4

in the third basipodite; the RiI has 3 setae, the Ri II@III 5 and the Re has 9 setae. The maxillac
and maxillipeds are scarcely different from Farran’s description.

The first pair of legs has the Se Re I extending to the base of Se Re IJ; in the outer edge of
the Re III, proximally to the middle, a distinct glandular pore is found, better developed than in other
species. The second pair of legs (text-fig. 62d) is like Farran’s fig. 16 Pl. V; the Se of Ril is
rather short and clumsy, and the St. of Re III has about 35 serrations, some of which are fused at
their base (text-fig. 62 f); the anterior surface of the appendage is minutely granular, and the posterior
one has, in addition to the usual spines, areas of smaller teeth. No glandular pores were observed.
The ¢hird pair of legs (text-fig. 62 e) has no distinct styliform process at the inner margin of the second
basipodite, and the slender terminal tooth of the anterior surface of the third basipodite medial to
the insertion of the endopodite is very short and clumsy; the posterior surface of the third basipodite
has a number of short spines in contrast to that of the second foot, which is smooth; in other respects
this pair-is like that of the preceding species. The fourth pair of legs has a long and slender second

COPEPODA 199

basipodite without marginal setae. The 4/7 fair of legs is like Farran’s figure, with a long and
strong inner seta, a rather short terminal seta, and a very delicate outer one; all segments are fused,
but the two basal ones are indicated.

The anterior portion of the /aérum is, in lateral view, less prominent than in preceding species;
in front of the labrum proper behind the transverse line, which limits the antennal somite, a tuft
of long setae is found. The arrangement of setae on the anterior surface of the /adrum (Pl. VII
fig 11a) is, as seen by comparing figures (cf. gb), like that of .S. odfust/rons, but the lateral posterior
group is better developed, and the central group has only a few setae. The oral surface of the labrum
is most like that of S. globicips’ (PL VII fig. 10a), but the granular area in front has much smaller
granules, and it is much smaller. The structure of the /aemzna labialis etc. is completely like that
of S. globiceps.

YS (St. V). Size. of young male from Thor St. 183 was 3:25 mm.; anterior division 2°51 mm.;
urosome 0°74 mm,

The only difference, except the usual one in the shape af the abdomen, is found in the more
obtuse inner tooth of the third basipodite of the fourth foot. The segment 10 of the antennulae has
a seta, but the segment 17 has no proximal seta. The fifth pair of legs is more slender than in S. 04-
tusifrons, but is alike in other respects.

Occurrence etc. The S/S Thor has gathered the species at a single station viz: ''/, 1904 St. 183
61°30 I. N. 17°08 L. W. Yt. 1800 M. Wire 5 £9, 2 yo (V). It has only been recorded once by Farran,
who has examined six specimens, taken at a depth of 700 fathoms off the west coast of Ireland. As to
the differences from the related species I refer to S. globiceps. The species is characterized by anten-
nulae about as long as the body, with a seta in segment 17. The Se of Rel pes I is fairly long and
slender, and the Se Ril pes II is rather short and obtuse. The St. of Re III pes II has 35 partly
fused teeth. The inner terminal seta of the anterior surface of Basp. III pes III—IV is only poorly

developed. The second basipodite of the third pair of legs has no spinous lamina.

63. Scaphocalanus globiceps Farran.
(Pl. VII figs toa—b; fig. 11 b; Pl. VIII figs 9a—c; text-figs 63 a—b.)
1905.? Scolecithricella gracilis n. sp. G. O. Sars, p. 2.
1908. Scolecithrix globiceps n. sp. Farran, pp. 54—55, pl. V figs 8—13, pl VI fig. 8.

Description. £9. Size of specimen from Thor St. 183 was 4:48 mm.; anterior division 338 mm.;
urosome 110 mm. Farran’s specimens measured 4:3—4'5 mm.

The body is more slender, and the abdomen comparatively longer than in the preceding species;
the fifth thoracic tergite is somewhat produced, but rounded. The rostral branches, arising from a short
basal part, are almost straight, stiff and fairly long, apparently longer than the pointed slender fila-
ments (text-fig. 63 a). The genital somite is only slightly produced below, and has an elongate, distally
not enlarged, receptaculum seminis (text-fig. 63 b). The comparative length between the abdominal
somites is 53, 35, 30 and ro, The serration along the posterior margin of the somites is distinct, at

least dorsally. The anfennulae extend to the end of the furca; the appendages differ from those of

200 COPEPODA

S. validus by the presence of a proximal seta in segment 17; the measurement is like that of the pre-
ceding species, but for the segments 8&9 and 19 which are of equal length. The manducatory part
has 3 setae in the third basipodite, but in other respects the mandzbulae as well as the antennae and
maxtilulae are scarcely different from those of the preceding species. The maxzillae and maxillipeds
show, as pointed out by Farran, a few rather unimportant differences.

The first pair of legs is scarcely different from Farran’s description, and the second pair is
very similar as well; the Se of the first outer segment is short and robust; the anterior surface of the
third basipodite as well as of the two branches is covered all over with areas of small spinules; on
the posterior surface the number of teeth is like Farran’s fig., but a patch of distinct teeth is found
near the apex of the third basipodite. The terminal seta is adorned with about 20, well separated, coarse
serrations. A glanduiar pore was observed at the base of Se 3 Re III. The ¢hird fair of legs has, along
the exterior border of the second basipodite, a low lamina, which, in the middle, has a row of 15— 20
fairly long spines not observed in the other species, and most distinct when
observed in situ; the spinulation, especially of the anterior surface, is better marked
than in the second pair; on the posterior surface of the third basipodite it is

scarcely better developed. The inner tooth of the anterior surface of the third

basipodite is short and rounded. The second basipodite of the fourth pair of legs
is comparatively less slender than in the preceding species; the inner tooth of
the third basipodite is just indicated; the spinulation of the anterior surface of
the basipodites as well as of the first outer and inner segments is well developed;

the distal segments. of the exopodites as well as the endopodites are wanting.

“4 Pr sae Mx The fifth pair of legs is scarcely different from Farran’s description.
caphocalanus globiceps ? - :
Farran. £9. The anterior surface of the dabrum seems, in most respects, to be like

oe oe that of .S. obtusifrons (Pl. VII fig. 9b), but the oral surface differs distinctly from
that species (Pl. VII fig. 10a, cf. fig. 9c); the most characteristic feature is found
in the distinct spinulation behind the marginal setae around the two first median circular spots and
as far lateral as the first well developed group of short spines; as to the other features I refer to the
figure. The damina labialis is scarcely indicated; in front of it, the usual inner and outer row is seen
(fig. 10 b); posteriorly, between the serrula 6-dentata, a median group of short spines is found, as well
as a paired one more behind. In the middle, behind the labial lobe, two more or less separated groups
of shorter and longer hairs are found, laterally continued into a wide oblique row along the inner
margin of the lobe. More laterally the lobe possesses an angle-shaped series of densely placed hairs
as well as a basal group without direct connection.

fh. Size of specimen from Thor St. 180 was 4:44 mm.; anterior division 2:99; urosome 1:45 mm.

The body is somewhat more slender than in the female, and the abdomen is about half as long
as the anterior division; the comparative length of the abdominal somites is 15, 45, 40, 45, 4 and 14;
the fureal rami are about 1.3 as long as wide. The antennulae reach somewhat beyond the end of the
third abdominal somite; the segment 13 is fairly well separated from 12, and segment 14 from 15, but
segments 20 and 21 are completely fused on the right side, but well separated on the left; beyond
segments 8x9 2 setae were found only in segments 12 and 14. Segment 22 is 1-4 shorter than seg-

COPEPODA 201

ment 19. The mouth-appendages are comparatively slightly transformed; the third basipodite of the
mandtbulae has, in addition to a fairly long Se 1 and a quite rudimentary Si 2, a small rounded process.
The maxillulae and the maxillae are scarcely less developed than in the female; the maxzllipeds are
comparatively less slender, but the amalliform seta of the second basipodite is well developed as in
the female. The zatatory legs are practically like those of the female, but the spinulation, especially,
of the anterior surface is less developed, and the medial terminal tooth of the anterior surface of the
fourth pair of legs is better developed; the terminal seta of Re III pes II has about 60 serrations. Along
the outer margin of the second basipodite of the third pair of legs, a lamina with a row of short spines
is found.

The 7th pair of legs, which in natural position is seen to extend a little beyond the end of
the abdomen is very much like that of .S. odtuszfrons. The right endopodite (Pl. VIII fig. 9 b) is rather
short, distally somewhat triangularly produced, and rather suddenly attenuated to a fairly long spine.
The right basipodite (fig. 9 a) is, outwards, produced into a long process which is fused with the first
outer segment; a terminal process of somewhat triangular shape, as in S. magnus, as well as a median
one is observed; the second outer segment is rather short and somewhat curved, and the third one is
short, flat, slightly curved and somewhat attenuated (fig. ga). The basipodites of the left foot are long
and slender; the comparatively short and slender endopodite is slightly curved, and indistinctly divided
into two proximal segments of about equal length as well as a short third segment with a fairly
slender terminal seta beyond a rounded process. The left exopodite is comparatively long and clumsy;
its first segment is the longer, and has two triangular processes, while the third one is the shortest,
and hairy (Pl. VII fig. 11 b).

Ley (St. V). Size of female from Thor St. 183 was 349 mm.; anterior division 2°71; urosome
o'78 mm.

The shape of the body shows the usual difference from that of the adult female: the distal
segments of the antennulae are comparatively longer; the segment 19 is 11 as long as segments 8~9Q;

the fifth pair of legs is somewhat smaller, but in other respects scarcely different.
Occurrence. The S/S Thor has taken this species at three stations in deep water viz:

‘Il, 1904 St. 285 62°49 L. N. 18°46 L. W. Yt. 500? M. Wire 1 f9.
to/, 1904 St. 180 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 2{9+1f¢.
1/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 2 £9, 3 £4, 2 y? (V).

Distribution. The species has only been recorded twice by Farran off the west coast of Ire-
land at 1000 and at 700 fathoms,

Remarks. This species is certainly identical with Farran’s species, as they do not differ in any
features of interest. Though, as far as the description goes, it agrees completely with Sars’ Scolecithri-
cella gracilis, especially in the structure of the fourth pair of legs, I prefer to refer it to Farran’s
species, as it is well distinguished from Scolecitricella according to Sars’ own definition.

The described male, which is well distinguished from that of .S. od¢as¢frons by its long and more

slender fifth foot, I have, on full consideration, referred to this species rather than to S. validus with
The Ingolf-Expedition. III. 4. 26

202 COPEPODA

which it agrees in a few features, on account of its size and the spinous lamina along the outer margin
of the second basipodite of the third foot.

Scaphocalanus globiceps, obtusifrons, validus and robustus seem to be nearly related, and are, without
detailed investigation rather difficult to distinguish from each other. In contrast to Scott, who refers
them to Scolecithricella, I follow Sars, and regard them as more nearly related to Scaphocalanus mag-
nus, with which they agree by the number of segments in the antennulae, by the appendages of the
maxillae, and by the structure of the fifth foot in the male. About the differences between .S. vodzstas
and globiceps I refer to the former species. The female of .S. globiceps is characterised by slender shape
comparatively short antennulae, which have a single setae in segment ro and a Spr. in segment 17.
Se ReI pes I is long and slender, and Se Ri I pes II is short and clumsy. St. Re III pes II has
about 20 well separated teeth. ‘The inner terminal seta of the anterior surface of Basp. III pes HI—IV

is only poorly developed. The second basipodite of the third pair of legs has, laterally, a spinous lamina.

64. Scaphocalanus robustus Th. Scott.
(Pl. VII figs 12 a—c; text-figs 64 a—c).
1894. Amallophora robusta n. sp. Th. Scott, pp. 56—57, pl IV | 1896. Scolecithrix robusta Th. Scott. Giesbrecht & Schmeil, p. 47.
figs 24—26. 1908. —- “= — Farran, p. 57, pl. VI fig. 3.

Description. £9. Size of specimen from Thor St. 167 was 2°78 mim.; anterior division 2°12 mm.;
urosome 066 mm. Scott’s specimen measured 3 mm. and Farran’s 2%65—31 mm.

The rostrum has rather short filaments (text-fig. 64a). The head is distinctly raised, and the
body is rather robust; the first thoracic somite is fused with the head, and the fourth and fifth thoracic
somites with each other; the lateral corners are slightly produced and rounded. The genital somite
is only slightly produced below; the receptaculum seminis is elongated and slender, but rather short
(text-fig. 64 b). The comparative length of the abdominal somites and the furcal branches is 33, 20, 18
10 and 14; the genital somite is almost as wide and deep as long, and the furcal rami are a little longer
than wide. The serration along the hinder margin of somites 2—4 is well developed.

The antennulae extend to the end of the genital somite; the limitation between segments 24
and 25 is rather indistinct; the appendages are like those of .S. globiceps, with a single seta in segment
10, and 2 in segment 17. The measurements are similar to those of the preceding species; the segments
1g and 16 are almost of equal length, and 1°3 as long as segments 8~ 9, which are, again, a little shorter
than segment 15. The antennae, mandibulae, maxillulae and maxillipeds are like those found in 'S.
globiceps. The maxillae possess 4 amalliform and 4 vermiform sensory appendages.

When the zadatory legs sitting on the animal are examined from the side, a curious difference
is found between the 3 first pairs and the fourth pair of legs in the basipodites as in related species;
the posterior surface of the three first pairs is seen to be excavated, while that of the fourth pair
appears cylindric, and in lateral view is almost twice as deep as that of the third foot. The frst foot
is very much like that of S. globiceps, but the Se Re I scarcely extends to the end of Re II (text-fig.
64). The second foot has the outer-edge spine of the first outer segment long and sickle-shaped, and
the outer-edge spine of the first inner segment short and rounded; the St has 30 short, well separated

teeth; the armature of the anterior and posterior surface is scarcely different from that of S. globiceps.
The third pair of legs is like those of the preceding species, but the outer-edge spinous lamina of the
second basipodite is wanting, and the posterior surface of the third basipodite has a patch of strong
spines, wanting in the second pair. The /ourth pair of legs is distinctly granular on the anterior sur-
face, but has fairly long spines in a longitudinal area on the two inner segments in addition to the
granulation; on the posterior surface of the two distal outer segments as well as on the distal inner one
a few short spines are observed; on the posterior surface of the second inner segment a transverse
row of 8 long spines is found. The 4/¢/ /ooé agrees fairly well with Scott’s and Farran’s description,
but the articulation is very indistinct.

The /aérwm is comparatively slightly produced in front (Pl. VII fig. 12a). The arrangement of
setae on the anterior surface is rather characteristic; in front a median group of fairly long bristles,
3—4 deep continued into a lateral group of a number of shorter hairs, extending laterally to in front of
a posterior lateral group of densely placed hairs. In the middle, later-
ally partly fused with mentioned anterior group, a transverse series
of comparatively few short setae. Add to this a marginal group of nu-
merous bristles.

The oral surface of the /abrum (P1. VII fig. 12b) shows some
similarity to S. validus, and in a less degree to S. globiceps; the granular
area around the first median circular spot is only small; the lateral
marginal and the first lateral group form a fairly long oblique group,

medially consisting of granules, and converging towards the second

median circular spot; the following lateral groups are in the main like

the structures in the preceding species. The arrangement of setae Text-fig. 64.

around the “/amina labialis’, and upon the labial lobes, is very much — S“¢P/ecalanus rodustus Th. Scott £9.

; : 3 a. Head X 18. b. genitalsomite 18.

like that of S. glodbiceps. c. Pes I sin. X 135.
Variation. In the first right foot in one of the specimens a median outer-edge seta was ob-

served in the third outer segment.
Occurrence. The S/S Thor has collected three females of this species at the following stations:

"9/6 1904 St. 152 65°00 L. N. 28°10 L. W. Yt. 1000 M. Wire.
/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire.
Ty 1905 St. 167 57°47 L. N. 11°33 L. W. Yt. 1500 M. Wire.

Distribution. This species has only been recorded twice, namely from the Gulf of Guinea ina
gathering from 85 fathoms (5/, 4°26 L.S. 10° L. E.), and from the west coast of Ireland “on four sta-
tions at depths of from 400 to 680 fathoms”.

Remarks. Though this species differs from that described by Scott by less robust shape, by
4 for 5 amalliform setae of the maxillae, and by the slightly different shape of the fifth foot, it seems
natural to regard the two as identical. It seems to be nearly related to .S. obtusifrons, but differs by a

more robust shape, by the structure of the third pair of legs, and by the longer antennulae.
26*

204 COPEPODA

65. Scolecithricella minor Brady.
(Pl. VII fig. 13; Pl. VIII figs 10a—c; text-figs 65 a—c.)
1883.? Scolecithrix minor n. sp. Brady, pp. 58—59, pl. XVI | 1904. Scolecithrix minor Brady. Wolfenden, p. 111.

figs 15—16, pl. XVIII figs 1—5. | 1905. — _ — Th. Scott, p. 223.
1892. ? _ — Brady. Giesbrecht, p. 266. | 1905. — a — Farran, p. 35.
1894. ? _ -- — Th. Scott, p. 50. 1906. Scolecithricella minor Brady. Pearson, p. 18.
1902. ? — Rémeri n. sp. Mrazek, pp. 513—515, Taf.6, | 1908. — — Farran, p. 51.

text-figs 11—13.
1903. Scolecithricella minor Brady. G. O. Sars, pp. 55—56, pls
XXXVII—XXXVIII.

1908. Scolecithrix minor Brady. v. Bremen, pp. 73—74, text-f. 85.
1913. Scolecithricella minor Brady. Stephensen, pp. 314—315.

1898. ? - -- — Giesbrecht & Schmeil, p. 46. | 1907. _ -- — Koefoed & Damas, p. 397.
|
|

Description. £9. Size of specimen from Ingolf St. 40 was 1°52 mm.; anterior division 1°22 mm.;
urosome 0:3 mm. Sars’s specimens measured 1-40 mm.

The antennulae extend slightly beyond the end of the thorax; the segments 1 and 2 are in-
distinctly separated, and so are segments 24 and 25; the segments 8~9 are almost completely fused
with 10. The Sp of segment 24 is placed terminally, and extends distinctly beyond the end of segment

a b c 25. The mouth-limbs are completely like Sars’ figures, and so are

/ the natatory legs; the second basipodite of the fourth pair of legs

has 3—4 rather stiff, marginal setae. In lateral view the third as

well as the fourth foot has in the second basipodite an outer-edge

lamina, which terminally is produced into a small tooth, much big-

ger in the fourth foot; this lamina has in the third pair, almost in
the middle, about 5 rather short and delicate teeth.

The dadvum and area in front of it is in lateral view very

Text-fig. 65. Scolecithricella minor Brady.
a—b. YG—Q (St. V). Abdomen x87. much like Sars’ figure Pl. XX XVII; the labrum proper and its an-

Ae lh a asasnasitins hse terior portion, which is only slightly prominent, have only a slightly
pronounced concavity between them. The améerior surface of the labrum is like that of .S. ovata (cf. Pl.
VII fig. 14.b); most anteriorly a transverse row of long slender bristles is found, continued laterally and
posteriorly into a row of shorter setae; behind this, almost in the middle, a transverse row of shorter
setae is found.

The oral surface of the labrum shows a great similarity to that of S. ovata (cf. fig. 14), but
the anterior lateral group is not well separated from the marginal setae, and the following group is
not convex outwards, and is directed towards the second median circular spot. The rudimentary /amina
labialis (P\. VII fig. 13a) scarcely shows features of great interest. The arrangement of hairs upon
and behind the labial lobes shows great similarity to Pl. VII fig. 14 b, but the median and the lateral
groups of hairs are fused.

fg. Size of specimen from Ingolf St. 4o was 1°34 mm.; anterior division o'99 mm.; urosome
0°35 mm. Sars’ specimens measured 1:40 mm.

The antennulae are like Sars’ figure, but segments 20% 21 bear only a single seta not two.
The mouth-appendages are very much like those of the female, except the mandibulae which have
the third basipodite distinctly longer than wide, the maxtliae which have the sensory setae better
developed, and the maxillipeds which are shorter and more clumsy. The xafatory legs are scarcely
different from those of the female. The Jifth foot is like Sars’ description; the left endopodite

COPEPODA 205

which is placed on a small protuberance, is short and clumsy, and indistinctly divided into two

segments.

¥g (St. V). Size of female from Ingolf St. 70 was 115 mm.; anterior division o'90 mm.; urosome
o25 mm. A young male from same station measured 1°17 mm.

The shape of the body is practically like that of the adult females; the first as well as the
fifth thoracic somites are fairly well marked in front. The antennulae extend somewhat beyond the
end of the body, but the measurements are scarcely different. The third and fourth feet are like those
of the adult female, and so is the fifth foot, except for the very indistinct lateral seta. The only dif-
ference between male and female is found in the structure of the fifth foot, which is seen in Pl. VIII
figs 10a—b (textfigs 65 a—b).

¥S (St. IV). Size of female as well as of male from Ingolf St. 19 was o795 mm.; anterior division
074 mm.; urosome o'2I mm.

The shape of the body is in main like adult female. The distal segments of the antennulae are
comparatively longer. The only difference between the sexes is found in the fifth pair of legs, the

structure of which is seen in figures (text-fig. 65c and Pl. VIII fig. 10 c).

Occurrence. Of this species the Ingolf Expedition has taken a big number of specimens while
the S/S Thor has not taken any specimens in the samples taken with the young-fish trawl.

In Davis Strait and in the Atlantic west of Greenland, the Ingolf Exp. has gathered it at
6 stations.

5/7 95 St. 29 63°34 L. N. 54°31 L.W. V*. 50—o fathoms. Temp. surf. 35°C. 1 f?.

/, 95 St. 27 64°54 L. N. 55°10 L. W. V*. 200—0 — — 39° C. 31 f9 (1 with sperm.), 10
| fd, 2 y?(V).

5/6 95 St. 24 63°06 L. N. 56°00 L.W. V1. 100—o 8=—_ — _ 42°C. 25 £9 (2 with sp.), 13 fd,
14 y2(V), 3 yo (V), 1 yo (IV).

26/6 95 St. 25 63°30 L. N. 54°24 L. W. V?. 200-0 = —- — ao? C. 8249, 12d, 17y9, 15 yd.

28/, 95 St. 36 61°50 L. N. 56°21 L. W. V*. 100—o0 “= — 85° C. 3 £9, In y?, 6yd, zy?
(IV), 3 yd (IV).

3°/, 95 St. 38 59°12 L. N. 51°05 L. W. V*. 100—o0 — = 10° C. 959 (10 with sp.), 15 fd,

5 y?(V), 10 yo (V).
In the Atlantic south-west of Iceland and east of Greenland the species was taken at 5 stations.

20/6 95 St. 20 58°20 L. N. 40°48 L.W. V*. 200—o fathoms. Temp. surf. 61° C. 4o f9 (1 with sp.), 16f¢,
13 y?(V), 10 yh (V).

8/6 95 St. 19 60°29 L. N. 34°14 L. W. V*. 300—0 —_ — 9° C. roof? (10 with sp.), 30
fd (3 with sp.), 15 y?(V), 5 yd (V), ty? (IV).

7/6 95 St.18 61°44 L. N. 30°29 L. W. V". 200—0 fathoms. Temp. surf. 10° C. 55 £2 (5 with sp.), 25
id, ry? (V), t yo (V).

3/6 96 St. 80 61°02 I). N. 29°32 L. W. P. 1o0o—o — 85° C. 1 yd (V).
19/6 94 St.17 62°54 L.N. 26°34 L. W. V". 200—0 — --- OI? C.. 4 to, Sissy Sot Vo:

206 COPEPODA

In Denmark Strait it was taken at 5 stations.

27/6 96 St.95 65°14 L. N. 30°29 L. W. Closing net. 700 fathoms 2 £9.

20/, g5 St. 11 64°34 L. N. 31°12 L. W. V%. 200—0 fathoms. Temp. surf. 82°C. ro f9, 1fd, 5 y9, 5 yo.
20/, 95 St.10 64°19 L. N. 28°52 L.W. V*. 200-0 8 — - vo", “Sto; ete:

20/. 95 St.g 64°18 L. N. 27°10 L. W. V*. 100—o0 - 6s bah, Soto OE Sse 3

19/5 95 St.8 63°56 L. N, 24°40 L.W. V'%. 100-0 8=—— — 85° C. 65 £2 (2 with sp.), 37 fd,

: : : I y?(V).
In the Atlantic south of Iceland it was taken at 6 stations.

9/3 95 St. 40 62°00 L. N. 21°36 L. W. V*. roo—o fathoms. Temp. surf. 13°5° C. 60 £9, 15 fd, 24 y? (V),
15 yo (V), 2 yh (IV).

3/6 96 St. 68 62°06 L. N. 22°30 L.W. V%. 100—O 3=—-— — 88°C. 4 £9.

116 96 St. 63 62°40 L. N. 19°05 L.W. V'. 100-0 8=—— _— 83°C. 26 £9, 6f5, 5 y?(V).
8/, go St. 54 63°08 L. N. 15°40 L.W. V%. 100-0, — 9g C. 10f?, 6f¢, zy, 2yh.
13/, 96 St. 49 62°07 L. N. 15°07 L. W. V4. 100-0 = — = 93°C. 15 £9, 5fd,6 v9, 4 yd.
12/, 96 St. 47 61°32 L. N. 13°40 L. W. V% 100-0 8=—-— 106° C. 58f£9 (10 with sp.), 22

fd, 3yP(V), 2 yd (V).
The Danish East Greenland Exp. 1900 has in surface hauls taken a few specimens, viz:

24/, F. 390 8 p.m. 61°06 L. N. 15°26 L. W. 4 f9.

F, 392 12 p. m. — — rif sig.
25/, F. 393 2 a.m. 60°29 L. N. 12°10 L. W. 15 £9, 6 f°

F. 4o2 8 a. m. -- — 1 f9.

F. 403 ae nex 3 F9, 1 yt (V).

2o/, F. 412 8 p.m. 60°13 L.N. 9°42 L.W. rf.

In the Iceland-Fzroe channel the Ingolf-Exp. has taken it in 5 samples.

™4/. 96 9°30 a.m. 64°13 L. N. 15°00 L. W. Apst. 6 ~ Temp. at surf. 78° C. 1 £9, 1 yo (V).

5/, 96 St. 52 63°57 L. N. 13°32 L.W. V*. 200—o fathoms. — 83°C. 8£92, 2iF, 2yZryd.

20/. 96 St. 57 63°37 L. N. 13°02 L.W. V's i0oo—o 8 — — $e°C i iP gidvi yeaa

1/, 96 St. 45 61°31 L.N. 9°45 L.W. V%. 200-0 — — gi1° C. 16f2 (4 with sp.), 8 id’,
. 9y2(V) 4 yd (V).

n/, 95 St.1 62°30 L.N. 8°21 L.W. V. 50-0 = — — pf eee OUR EA

North-east of Iceland the Ingolf Exp. has taken it at two stations.

5/, 96 St. 119 67°53 L. N. 10°19 L. W. P. 100—o fathoms. Temp. at surf. 5° C. 1 £9.
a6/, 96 St.117 69°13 L.N. 8°23 L. W. Vi100—o 8=—— _ 41°C. ry?(V).

Outside the Ingolf area, specimens were examined from two localities, viz:

Dan. East Gr. Exp. 1900 *"/5 1 p.m. 63°33 L. N. 0°04 L. W. Closing net. 7550 fathoms. 1 f9.
Joh. Petersen 93° GaN Oly 3 £9, 2 y?(V).

COPEPODA 207

Distribution. Brady’s specimens were taken in the Indian Ocean 47° L. S. 45° L. E. at the sur-
face. By Th.Scott it was recorded from the Gulf of Guinea, and, according to Farran, it is fairly com-
mon off the west coast of Ireland at depths of from 100 to 1000 fathoms; occasionally it has been found
at or near the surface. According to Sars it is a true pelagic form (often occurring close to the sur-
face of the sea), which is found along the greater part of the Norwegian coast as far north as Lofoten
Islands, as well as sometimes in the open sea. In the sea between Spitzbergen and Greenland as far
north as 80°17 L. N. the Duc d’Orléans has gathered this species in 32 samples from about 80, between
7/, and *5/s 1905, as well in cold as in temperate water. It was neither found at the very surface
nor below 500 meters, but in 12-out of 14 samples taken at a depth of from 100 to 200 meters, gene-
rally scarce never abundant; in 8 samples adult males as well as females were found at a depth of
from 20 to 400 meters.

Remarks. I have followed Sars in referring the northern form to Brady’s species from the
Indian Ocean, though his description is too incomplete for a certain identification. In spite of minor
differences, f. inst. in the shape of pes V of the adult female, I am fairly convinced that Mrazek’s
S. Rémeri is identical with this species. As the species has not been found, as far as I know, in any of
the extensive collections from the South- and Mid-Atlantic or Indian Oceans, I think we are entitled
to regard this species as one which has its chief centre of distribution in the North-Atlantic and in a
less degree in the Arctic seas cummunicating with it. It seems not to have been found in the North
Sea proper or adjacent waters; may be on account of lower salinity.

The records of the “Ingolf”’ which are all from the months May to July, and almost all with
the vertical net down to about roo fathoms, tell the same story as the above mentioned records of the
Duc @Orléans; that the species in these regions and at this season is only exceptionally found at the
surface; if it were not so, it must have been found in several of the numerous surface samples from
the Ingolf or the Danish East-Greenland Exp. It is worth recording that the species was found in
several surface samples gathered from the mentioned expedition in the month of September, south-
west of the Feeroes. The Ingolf material does not allow any final conclusion about the time of pro-
pagation, but as adult males were found in 19 out of 24 samples (in a percentage varying from about
10 to 50) taken from May to July, and as spermatophores were often attached to the genital somite
of the female as well as sometimes to that of the male, it is almost certain that the species is propagating
then. The Duc d@Orléans found only males in 8 out of 32 samples. Adult males were gathered south-
west of the Feeroes in the month of September. Young animals of the penultimate stage were found

in most samples, except in those from the month of September.

66. Scolecithricella Ingolfii n. sp.
(Pl. VIII figs 11 a—c).

Description. {9. The shape of the body is practically like that of S. minor; the head is perhaps
a little more raised. The lateral corner is, like that of preceding species, somewhat triangularly produced.
The antennulae and oral appendages are completely like those of S. mznor.

The frst pair of legs is scarcely different; the first inner segment of the second foot has a

208 COPEPODA

fairly distinct pointed outer spine; the outer-edge lamina of the third pair of legs has no spines.
Along the inner margin of the second basipodite only two setae are observed; the inner terminal tooth
of the third basipodite is longer and more slender. The 4th pazr of legs is fairly well developed, with
three indistinct segments (fig. 11 b); on the left side two indistinct terminal setae are found; on the
right side the endopodite is indicated by a small process, and the exopodite has, inwards, a distinct
spine. A similar asymmetric structure was also observed in a specimen from Ing. St. 19. In a spec-
imen from Ing. St. 9, the left leg had a somewhat better developed endopodite, and the exopodite had
a terminal and an inner seta, fairly long and placed nearer the tip than the base. In the specimen
from @. Exp. 1900, the legs were symmetrical, and showed, as seen in Pl. VIII fig. 11 c, a somewhat
different structure.

Occurrence. The Ingolf Expedition has gathered this species at three stations viz:

1/, 1895 St. 27 64°54 L. N. 55°10 L.. W. V'. 200—0 fathoms Temp. at the surface 39°C. 2 £9.
18/, 1895 St. 19 60°29 L. N. 34°14 L. W. V4. 300-0 — -- _ 6s Cee
20/, 1895 St.9g 64°18 L. N. 27°10 L. W. Vi.100-0 = — —_ o: Ci gee

The Danish East-Greenland Expedition has *5/, 2 p.m. 1900 60°19 L. N. 22°10 L. W. F. 399
gathered a single adult female.

As far as I was able to ascertain, this species has not been described hitherto. It is very much
related to S. minor, and it is not without doubt that I have established it as a new species, as, at
almost all the localites it was found in company with that species; but as the character found in the
much longer fifth foot was found to be fairly constant in spite of small variations, I thought it
right to do so.

67. Scolecithricella ovata Farran.
(Pl. VII figs 14a—d; Pl. VIII figs 12 a—f).

1905. Scolecithrix ovata n.sp. Farran, p. 37, pl. VI figs 13—18, | 1908. Scolecithrix ovata Farr. Farran, p. 51.
pl. VIII figs 1—5. | 1908. -- — — v. Bremen, p. 72, fig. 83.
1906. Scolecithricella ovata Farr. Pearson, p. 18.

Description. Size of specimen from Ing. St. 19 was 2°32 mm.; anterior division 1°84 mm.; uro-
some 048. Another specimen measured 2°5 mm. Farran’s specimens measured 2:3 mm.

The shape of the body is in main features like Farran’s description; the head is fairly well
raised, and the rounded lateral-corners are slightly produced. The first and the fifth thoracic somites
are not marked out in front. The rostrum consists of two short, obtuse, slightly divergent teeth, arising
from a short lamelliform undivided process, to which are attached fairly slender and apparently obtuse
rostral filaments, several times longer than the rostrum proper and, in direction downwards and back-
wards, reaching beyond the insertion of the antennulae; these filaments are wanting in most specimens.

The abdomen has the genital somite only slightly produced below; the receptaculum seminis
is elongated-pear-shaped, and generally very prominent. The comparative length between the abdominal
somites and the furcal rami, which are almost twice as long as wide is 22, 12, 14, 3 and 12.

The antennulae have 23 segments of which the segments 24 and 25 are completely fused; they reach

COPEPODA 209

about to the end of the third abdominal somite. The extennulae appear rather clumsy, and their
measurements are scarcely different from Farran’s figures. A proximal seta, in addition to the distal
one, was found in segments 12, 14 and 18; in contrast to Farran’s fig. 14 no seta whatever was ob-
served in segment 10; the posterior seta of segment 24 is short, and scarcely extends beyond the end
of segment 25. The antennae are like those of S. minor, but the inner lobe of the endopodite has only
7 setae. The mandibulac have on the inner side of the long and slender third basipodite two long
setae placed close to each other, of which the basal is the longer and stronger; the last segment of
the exopodite has 9 long setae. The maxzillulae have 7 --2 setae in the outer lobe. Li I has 2, Li II
3 setae, Basp. III has 4 setae and Ri I—III 3+ 3 setae. The exopodite has 5 setae. The maxzllae are
like Farran’s figure, and possess numerous vermiform, but no amalliform, setae (Pl. VII fig. 14a); the
maxillipeds are like Farran’s figure, but the second lobe of the second basipodite bears a fairly long,
terminally hooked, and soft sensory seta.

The first foot has a well developed Se in the first outer segment, almost reaching the middle of the
following segment. The second foot has the second basipodite rather broad; medially proximally to the
insertion of Si a small tooth is observed, and laterally the margin is proximally produced into a strong
tooth; the Se of the first outer segment is long and slender, and the St of Re ITI has about 55 basally
fused teeth. The spinulation of the posterior surface is better developed than indicated by Farran.
A glandular pore was observed at the base of Se 3 Re III. The third pair of legs has a well devel-
oped outer tooth in the second basipodite, and a short inner one, resembling that in the second foot
of S. obtusifrons. The fourth pair of legs has no inner marginal bristles in the second basipodite, and
no outer tooth. The St has a rather curious structure, as the marginal serrations are not completely
coalesced basally, leaving an elongated fenestra. Spinulation, consisting of about 15 rather small teeth,
is found on the posterior surface of the second inner segment.

The fith pair of legs is in the main features like Farran’s figure, with the first basal segment
well distinguished, and with the second more or less well separated from the broad lamellar third
segment. The legs are generally asymmetrical, partly because the articulation is better developed on
the left than on the right side, and partly because the number of setae is rather variable. On the left
side we generally find a shorter terminal and a longer distal seta as figured by Farran, on the right
sometimes the terminal and sometimes the medial seta is absent, but often both are present.

The anterior portion of the /aérwm is distinctly prominent in front; the anz¢erzor surface shows
a rather simple arrangement of the bristles (fig. 14 b) most similar to that of S. odtusifrons, though
less complicated; in addition to the marginal rows of bristles an anterior transverse distinctly convex
row, composed of several units, and a posterior shorter one are observed. The ora/ surface of the labrum
has the anterior lateral group fairly well separated from the marginal rows (fig. 14); the posterior
groups of the longitudinal series are, as seen in figure, more or less fused. As seen in fig., the trans-
verse median groups are rather poorly developed. The structure of the “/amina labialis’’ etc. is in the
main like that of the preceding species. The arrangement of the hairs upon and behind the labial lobes
shows, as seen in fig. 14b, a very marked difference between a central and two lateral groups.

The intestine is not straight, but distintly twisted, at least vertically, though in a less degree

than in Lophothrix frontalis.
The Ingolf-Expedition. III. 4. 27

210 COPEPODA

wg (St. V). Size of young female from Ing. St. 19 was 1°86 mm.; anterior division 1°47; urosome
0:39. Another female from Thor St. 82 measured 16 mm.

The shape of the body is like that of the adult female; the comparative length of the abdominal
somites and the furcal rami is 7, 9, 9, 11 and 9. The antennulae reach the base of the furea; the
distal segments are comparatively longer. The inner lobe of the last segment of the endopodite of
the antennae has 8 setae, in other respects the mouth appendages were scarcely different; no dif-
ference of interest was found in the structure of the natatory legs. The th pair of legs in the female
is scarcely different from that of adult, but showed in the male, as seen in fig. 12f Pl. VIII, a rather
characteristic structure, as the left leg is much longer than the right one.

Y¢ (St. IV). Size of male from Ingolf St. 27 was 1°38 mm.; anterior division 1° mm.; uro-
some 0°28.

The difference between this and the preceding stage is found in the abdomen, consisting of
three somites, the comparative length of which was 6, 9, 12 and 7. The antennulae reach only to the
middle of the last abdominal somite.

The frst foot differs from that of preceding stage by the fused Re II—III; the second foot
showed the same feature, and its second basipodite has no outer tooth, while the spinulation was

scarcely different. The left 7/¢/% foot is somewhat longer than the right, and each foot consists of three
segments; no setae were observed.

Occurrence. The Ingolf has gathered this species at 4 stations in Davis Strait:

"/, 95 St. 27 64°54 L. N. 55°10 L. W. V*. 200—0 fathoms Temp. at surf. 3:9°C. 3£9, 1 yh (IV).

26/6 95 St. 25 63°30 L. N. 54°25 L.W. V. 200-0 — _ 29° C. 9 9, 5 yP (V).
3°/, 95 St. 38 59°12 L. N. 51°05 L. W. Vi. 100-0 =—- — ie ro? C. 6 £9.
25/6 95 St. 24 63°06 L. N. 56°00 L. W. V'. 100-0 8 — — ga°C. 22%

In the Atlantic south-west of Iceland it was taken:

20/, 95 St. 20 58°20 L. N. 40°48 L. W. V*. 200—0 fathoms Temp. at surf. 61°C. 2 y? (V).

18/6 95 St. 19 60°29 L. N. 34°14 L. W. V4. 300-0. — 9° CG. 25 £9, 3 yS(V), 3 yP(V).
17/6 95 St. 18 61°44 L. N. 30°29 L. W. V. 200-0 —— _ to? C. rf9.
16/5 g5 St. 17 62°54 L. N. 26°34 L.W. V". 200-0 =—— -— g1°C. 5 £9.

In Denmark Strait the Ingolf took it:

20/. o5 St. 11 64°34 L. N. 31°12 L. W. V'. 200—0 fathoms Temp. at surf. 82°C. 1 £9, 2 y? (V).
In the Atlantic south of Iceland:

12/, 96 St. 47 61°32 L. N. 13°40 L. W. V*. 100—0 fathoms Temp. at surf. 106°C. 5 f9.
The “Thor” has gathered the species at a single station:

8/6 1905 St. 72 57°47 L. N. 11°33 L. W. Yt. 1500 M. Wire 2 f?.
15/6 1905 St. 82 51°32 L. N. 12°03 L. W. Yt. 1200 M. Wire 1 y@.

Distribution etc. This species has previously been recorded only from the west coast of Ire-

land, where it seems to be of frequent occurrence over deep water from the surface to 1000 fathoms,

COPEPODA 211

but only in small numbers. In spite of small differences I do not doubt that my specimens ought to
be referred to Farran’s .S. ovata. As the maxillae do not possess any amalliform setae, I have referred
the species to Scolectthricella, though in several respects it shows great similarity to Scaphocalanus

obtusifrons, and perhaps is more related to this species than to Sc. mznor.

68. Lophothrix frontalis Giesbr.
(Pl. VII figs 7a—d; text-figs 66a—f and 67 a—d).

1895. Lophothrix frontalis n. sp. Giesbrecht, p. 254, pl. II. 1906. Scolecithrix frontalis Giesbr. Esterly, p. 65 pls 9 & 13.

1898. Scolecithrix frontalis Giesbr. Giesbrecht & Schmeil, p. 49. | 1908. Lophothrix frontalis Giesbr. Farran, p. 58.

1903. _ _ — J.C. Thompson, p. 21. 1908. Scolecithrix frontalis Giesbr. v. Bremen, pp.79—80, fig. 93.

1904. Lophothrix frontalis Giesbr. Wolfenden, p. 120 pl. IX | 1909. Lophothrix frontalis Giesbr. A. Scott, p. 99, pl. XXVI figs
figs 41—42. 11—20, pl. XX1X figs 1—10.

1905. — _— — G.O. Sars, p. 6. IgIt. _ — — Wolfenden, p. 268.

1906, = = + Pearson, p. Ig.

Description. £9. Size of female from Thor St. 72 was 645 mm.; anterior division 5:18 mm.;
urosome 127mm. Giesbrecht’s specimen measured 66 mm., Scott’s 7-4, and Wolfenden’s 55-60 mm.

The genital somite is slightly produced below and-has an elongate receptaculum seminis, which
is directed upwards and forwards (text-fig. 66a). Along the hinder margin of somites 2—4 a well devel-
oped serration is found; the third and the fourth somites possess dorsally and anteriorly transverse
groups of short spines.

The antennulae, which extend beyond the end of the third abdominal somite, consist of 24 seg-
ments, as segments 24 and 25 are fairly well separated. “AYsthetasken” are, in contrast to Scott’s figure,
beyond segments 8~9 only found in segments 12, 14, 19 and 25. The segment 10 possesses a well
developed seta, and a proximal seta is beyond segment 8~9 only found in segments 12, 14 and 18.
The Sp of segment 24 extends distinctly beyond the end of segment 25. Segments 8~9 are only a
little shorter than segment 18, which is a little longer than segment 17 as well as 19, which is 12 as
long as segment 20. The an/ennae are like Giesbrecht’s figure, with the exopodite a little longer
than the endopodite, which has 8 setae in the Li and 6 in the Le. The third basipodite of the man-
dibulae has three long convex setae; the first inner segment has 2 setae, and the second has 9. The
maxtllulae are like those of S. magnus, with 7 + 2 setae in Le, 14 setae in Lil, 2 in Li I, 5 in Li III
and 4 or 5 in basipod. III. The Ri I has 3 setae, the Ri II~III 5 setae, and the Re has 9g setae.
The shape of the maxiillae is like that of fig. 14a; amalliform as well as vermiform setae are found.
The maxillipeds are like Giesbrecht’s description. The second, third and fourth pairs of legs do not
show the marked difference in the second basipodite when observed in lateral view in situ; in the
second and third feet an outer-edge lamina is found, but neither spines nor distal tooth. The first outer
segment of the frst foot has no outer seta. The second foot has a well developed long outer spine in
the first inner segment, as figured by Giesbrecht; the anterior surface is smooth, but the posterior
surface has a number of short spines, as seen in fig. 7a Pl. VII. The fourth pair of legs has the inner
margin of the second basipodite smooth; the third basipodite has, like the third pair, a small inner
tooth on the anterior surface near the end; a few teeth were found only on the posterior surface of the

two inner segments. The 7th parr of legs is scarcely different from Giesbrecht’s description.
27*

212 COPEPODA

The /abrum is, as seen in Wolfenden’s fig. 41, more elongated than that of .S. magnus (Pl. VII
fig. 8a), and strongly produced in front; the hinder portion of the labrum is, as in most other species,
marked by an anteriorly convex line. I am fairly convinced that the anterior as well as the posterior
portion of the labrum belongs to the mandibular and not to the antennal somite; the anterior portion,
accordingly, does not correspond to the epistoma of Euchete. The arrangement of bristles on the
anterior surface is very characteristic (Pl. VII fig. 7 b). In the middle, most anteriorly, is a forward convex
row of about 30 long bristles. A little more posteriorly we have on each side a long row extending
laterally from the middle in front towards near the hinder margin; the setae of this row are decreasing
in length posteriorly; the right and the left parts establish an acute angle open posteriorly, and,
thus include a more posterior row, forming a more obtuse
angle, of shorter setae.

In addition to the marginal setae, posteriorly irregular
groups of short setae are found on each side. The oral
surface of the labrum is rather characteristic, the first
group is poorly developed, consisting of smail granules ©
and is well separated from the groups 2—4, which are more
or less fused and consist of fairly strong, densely placed
setae; behind, a group of small granules is observed (fig.
7c, which is turned upside down). A damina labialis (fig.

7d Pl. VII), consisting of a median and two lateral parts,
is found. In front of the serrula 6-dentata are two rather

4 irregular rows of delicate setae, as seen in figure. Between

Ge NH the serrulae at least two groups of short spines and a

AY longitudinal row are seen on each side. The dodus labialis

b LA» d f possesses a wide inner row of numerous hairs, and an
Text-fig. 66. Lophothrix frontalis Giesbr. outer one of few hairs; both rows start posteriorly from

a. £9. Genital somite 33. b. YQ (St. V) Pes V “ pees ; :
X59. ¢. Yo (St. V). Abdomen X 33. d. Yo (St. V). @ median group consisting of an inner portion with
Pes V X59. e Yo (St. IV). Abdomen X 33. f. Yo

numerous densely placed hairs, and an outer portion with
(St. IV). Pes V X 59.

scattered hairs. More posteriorly and laterally, two groups
of a few hairs as well as irregularly placed hairs are found. The intestinal tract is curiously twisted.
In front of the oesophagus a short coecal sac is observed; behind, the stomach is gradually attenuated,
and forms a slight ventral convexity. At the insertion of the third pair of legs the intestine is
suddenly, in a sharp bend, turned upwards and directed forwards, being thus placed dorsally to the
mentioned part; somewhat in front of the maxillipeds it is continued through a second curvature
into the intestine proper.

fg. Size of male from Thor St. 183 was 5°66 mm.; anterior division 4:19 mm.; urosome 1-47 mm.
Scott's specimens measured 5°75 mm.

The body is slender and attenuated in front as well as behind; in dorsal view, scarcely in
lateral, a trace of rostrum, is observed. The rostrum is on each side continued into two fairly long

COPEPODA 213

and slender spines (text-fig. 67a). The fifth thoracic somite is well distinguished in front, and the
regularly rounded lateral corners are scarcely produced.

The abdomen is one third as long as the anterior division; the comparative length of the
abdominal somites and the furca is 18, 67, 53, 48, 10 and 18. :

The antennulae extend at least to the end of the third abdominal somite; the shape is similar
to that of S. magnus, but the proximal part is straighter, the restrictions at the base of the basal
segments are less pronounced, and the angle between segments 14 and 15 in less marked. Segments
89 are almost completely fused with 10o—12, segments 20 and 21 and 24—25 are completely fused.
The appendages are scarcely different from those of .S. magnus; the segment 20 does not possess any
setae. The segments 8~12 are 1'r as long as segments 23—25, not, as in .S. magnus and related species,
much (1°5) shorter, and segment 22 is 12 shorter than segment 19. The axzfenna are scarcely different
from those of adult females, and the mandibulae are very much like, but the manducatory parts are less
powerful, and the third basipodite is comparatively wider, with two short setae inwards, and a more
distally placed knob representing a third one. The Li 1 of the maxtllulae is fairly well developed,

and has at least 12 rather short and soft setae; in Li

III only 4 setae were observed, but in other respects
searcely any difference was observed. The maxillac 7) \ . f d
have the sensory appendages, especially the amalliform
ones, slightly developed; the maxillipeds are like those b
of S. magnus.
The natatory legs are scarcely different from
those of the female. The #/¢/ pair of legs extends

almost to the end of the abdomen, and shows great

Text-fig. 67. Lophothrix frontalis fd.
: 5 : a. Head * 18. b. Abdomen 18. c. Pes V dext.
which extends somewhat beyond the end of the first Re II—III x 59. d. Pes V sin. x 59.

similarity to that of S. magnus. The right endopodite,

outer segment, is styliform, with the terminal part
fairly well articulated. The right exopodite (text-fig.67c) has the first segment articulated upon a
long outer process of the third basipodite as long as the segment itself; the two pieces form a natural
joint, elongated and outwards convex; the second outer segment is much shorter than the first; the
third somewhat lamelliform segment is again somewhat longer, convex inwards, with a distinct angular
process in the middle directed forwards, and produced into a pointed eminence, at the base of which
a small conical process is found. The basal segments of the left leg are long and slender, and of almost
equal length; the left endopodite (text-fig. 67 d) is like that of S. magnus, with the two first segments
long and slender, and the third rather short and pointed; the left exopodite is somewhat shorter than
the endopodite, and its third segment is triangularly attenuated, with fairly long setae inwards and
terminally and short ones outwards.

The anterior surface of the labrum is very much like that of the female; anteriorly three
irregular series of apparently very short setae are found; the series along the hinder margin is wanting.
The oral surface has anteriorly a small conical process on each side, behind which at least two striated

median spots are found; on each side an irregularly striated protuberance was found; no hairs were

214 COPEPODA

observed. The /amina labialis seems to be represented by a transverse crest; in front of it on each
side a longitudinal area of very minute hairs is found, and behind, a serrula 6-deutata consisting of
rather short setae is observed. The /adzal lobes are well developed, but no setae are observed upon them.

Ye (St. V). Size of female from Thor St. 72 was 488 mm.; anterior division 3°80 mm.; urosome
108 mm. Male from the same station measured 5:37 mm.

The young animals are in most respects like those of the adult females; the fifth thoracic
tergite is distinctly marked out (text-fig. 66c). The only difference is found in the structure of the
fifth foot, which in one female was scarcely different from that of the adult, while in another, probably
a variation, the distal outer seta is comparatively short, but in addition to it another proximal one is
observed, and the endopodite is indicated by a short rounded process (text-fig. 66b). In the male the
setae are short, and a long endopodite is found (text-figs 66 b—d).

5 (St. IV). Size of male from Thor St. 167 was 3°48 mm.; anterior division 2°90 mm.; urosome
058 mm. |

The shape of the body shows the usual differences; the lateral corners are slightly more produced
(text-fig. 66). The mouth-limbs are scarcely different, but the 3 last natatory legs have the number
of segments reduced; the second foot, f. inst. has the 2 last outer segments fused with 3 outer spines
only; the number of teeth on the posterior surface is smaller. The //¢h foot of the female has 3 seg-
ments, a strong terminal spine, and a short outer spine, but no inner one. The fifth foot of the male
is, as seen in text-fig. 66f, distinctly smaller than in preceding stage.

Occurrence. The Ingolf has not taken this species, but it was gathered at several stations by
the “Thor”.

In Denmark Strait:

19/6 1904 St. 152 65°00 L. N. 28°10 L. W. Yt. 1000 M. Wire 10 f?, 1 y? (V), 4 yh (V).

20/6 1904 St. 153 65°27 L. N. 27°12°5 L. W. 6 £9, ry dh (V).
21/6 1904 St. 154 65°27 L. N. 27°10 L. W. 3 £9, rid’, 2 y2 (V).
In the Atlantic South of Iceland:
12/, 1904 St.78 61°08 L. N. 28° L. W. I y@ (V).
ly 1904 St. 285 62°49 L. N. 18°46 L. W. 14 £9, ry?(V), ry cd (V).
t/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 15 f9, 8 id.
25/, 1904 St. 104 62°47 L. N. 15°03 L. W. 7£9; rid, ry? (V), 2 yc (V).

In the Feeroe-Iceland channel:
22/; 1904 St.g9 61°15 L.N. 9°35 L.W. Yt. 1700 M. Wire 1 f9.
Yt. goo M. Wire Le Re
4/, 1904 St. 230 63°10 L. N. 7°31 L. W. Yt. 1200 M. Wire 1 f9.
12/, 1904 St. 78 61°07 L.N. 9°30 L. W. 2 £9.
29/, 1905 St. 165 60°00 L. N. 10°35 L. W. Yt. tooo M. Wire 1 £9, 1 yo (V).
Outside the Ingolf area:

15/6 1905 St. 82 51°32 L. N. 12°03 L. W. Yt. 1200 M. Wire 5 £92, 1 y$(V), ry dh (V).
Yt. 800 M. Wire 19, 1 yh (V).

COPEPODA 215

t/, 1905 St. 167 57°46 L. N. 9°55 L. W. Yt. 1500 M. Wire 81 £9, 1 y?(V), 1 yQ (IV).
8/6 1905 St. 72 57°52 L.N. 9°53 L. W. Yt. 1500 M. Wire 58f9, 3 y?(V), 25ych'(V), 1 yo (IV).
20/, 1905 St. 88 48°09 L.N. 8°30 L. W. Yt. 300 M. Wire 18 £2, 2 y2(V), 5 yc (V).

Distribution. This species is probably distributed all over the Atlantic as far north as Den-
mark Strait and as far south as 35° L.S. It has been recorded from the Pacific (35° L. N. 125°
L,. W.), from the Gulf of California where, according to Esterly (1912 p. 321), it is found between 50
and 300 fathoms, and from the Malay Archipelago. According to Farran it is a not uncommon species
in the N. E. Atlantic. “It was taken on every station at all depths from 330 to 1150 fathoms, and in
fifteen out of thirty-four gatherings”.

Remarks. In spite of a few minor differences, partly enumerated above, I regard this species

as identical with Giesbrecht’s, Scott’s and Wolfenden’s species.

69. Scottocalanus Thorii n. sp.
(Pl. VI figs 14a—c, Pl. VIII figs 14a—b, text-figs 68 a—i, 69a—d and 70 a—d).

1893. i nec. 2 Scolecithrix securifrons n.sp. Th. Scott, pp. 47— | 1905. nec. ScoJecithrix persecans Giesbr. Esterly, pp. 168—167,
48, pl. IV. fig. 28.
1895. nec. -- persecans n. sp. Giesbrecht, pp. 253— | 1906.?pars.Scottocalanus securifrons Scott. Pearson, p. 19.
254, Taf. 3 figs 6—12. 1908. — persecans Giesbr. Farran, p. 58.
1898. nec. — — Giesbr.Giesbrecht &Schmeil, | 1908. nec. Scolecithrix persecans Giesbr. v. Bremen, pp. 80—81.
p- 58. 190g. nec. Scottocalanus persecans Giesbr. A. Scott, pp. 105—
1903? — _ — J.C. Thompson, p. 20. 106, pl. XXVII figs 10—18.
1904? “ii = — Cleve, p. 197. IgII. pars. Lophothrix securifrons Scott. Wolfenden, p. 268.
1905. Scottocalanus securifrons Soott. G. O. Sars, p. 7.

Description. f£9. Size of female from Thor St. 82 was 4°69 mm.; anterior division 3°91 mm.;
urosome 078 mm. Esterly’s specimens measured 4°6 mm. :

The rostrum is very strong, and only terminally subdivided into two rather short divergent
branches without terminal appendages (text-figs 68a—b). The eyes are well developed. The forehead
is surmounted by a short, rather prominent crest. The shape of body is, as seen in text-figs 68 c—d,
somewhat robust, and the anterior division is almost five times as long as the abdomen. The first as
well as the fifth somites are fused with the preceding ones; the lateral corners are somewhat triangularly
produced, but are obtusely rounded, with a small notch.

The genital somite, which is about as long as the following three somites, is moderately pro-
duced below, but the hinder and ventral corner does not project beyond the following somite. No
serration was observed along the hinder margin of the abdominal somites.

The antennulae extend at least to the end of the third abdominal somite; segments 8~9 are
well separated from 10, and segments 24 and 25 are fairly well separated. The appendages differ from
those of LZ. /rondals by wanting a seta in segment 10, and by the delicate Sp. of segment 24, which just
extends beyond the end of segment 25; the segments 8~9 have two soft setae (text-fig. 68e). The
measurements are very much like those of Z. /rontalis. The exopodite of the antennae is almost 1°5 as
long as the endopodite, which has 8 setae in the outer and 6 in the inner lobe of the second segment.

The mandibulae are in the main like those of Z. frontalis, but the third basipodite has only two setae;

216 COPEPODA

the maxillulae differ from those of the mentioned species by 3 setae in the second inner lobe and 8
setae in the exopodite. The posterior margin of the maxzllae is only slightly convex, and only a few
slightly developed amalliform sensory setae in addition to the vermiform one were observed. The
maxillipeds are like those of the preceding species, but the amalliform seta of the second basipodite
is rather slender, and the endopodite is comparatively elongate.

In lateral view the second basipodite of the second and third foot has an outer-edge lamina
with a prominent distal tooth.

The frst foot has 3 outer segments; the outer spine of the first segment extends somewhat
beyond the middle of the second segment; in the
outer margin of the third segment a distinct glan-
dular pore is found near the base. The second pair
of legs (text-fig. 68 f) has a large somewhat rounded
outer tooth in the first outer segment. The ter-
minal seta has about 30 well separated serrations.
The posterior surface of Ri II~ III has 6 strong

“spines, and the anterior one a few shorter ones.
The posterior surface has a single row of teeth in
the second outer segment and two rows in the third.
Indistinct glandular pores are found at the base ~
of Se Re II and Se 3 Re III. The ¢hird pair of
legs has a well developed inner tooth terminally
on the anterior surface of the third basipodite; the
third to fifth serration of the terminal spine is
shorter than the more proximal and distal ones; the
arrangement of the spinules is less developed
than in the second pair of legs. The fourth foot
has a short clumsy second basipodite without mar-

ginal setae outwards; the endopodite has no teeth

posteriorly, but has a few on the anterior sur-
Text-fig. 68. Scottocalanus Thorti u. sp. £9. face of Rill and III, as in the preceding pairs;
a. Head X18. b. Rostrum X 33. c. Abdomen in dorsal the exopodite is almost smooth. Well developed
view 15. d. Abdomen in lateral view 15. e. Segments : 3
VII—X of the antennulae. f. Pes II dext. in anterior view. glandular pores are found in ReI as well as in
g. Pes V in anterior view 59. h. Base of spine in posterior Fes :
view 150. i. Base of spine in partly anterior view X 59. Red edi Lad as hese of legs thes: three father
indistinct segments; inwards a small conical pro-
cess bearing a short spine and, with a rudimentary hair at the base of the strong outer spine, almost
extending to the end of the third abdominal somite; in the distal half the spine is interiorly serrated,
and terminally, a few hairs are found outwards (text-figs 68 g—i).
The lateral view of the /abrvum is like that of S. magnus, but the anterior part of the labrum
is less produced, and in front of it a smooth, rounded elevation is found. The anterior surface of the

labrum (Pl, VI fig. 14.) shows some similarity to that of Z. /ronfailis (Pl. VII fig. 7b). Most anteriorly

\

COPEPODA 217

a curved row of fairly long setae, in the middle connected with the opposite side, is found; somewhat more
posteriorly, and extending from the middle anteriorly to the hinder margin posteriorly, an elongated
semicircular row is found (in fig. 14a, this row is wrongly represented as being separated from that of
the opposite side); this row is several setae high, and the length of its setae decreases backwards.
More posteriorly another convex row of shorter setae is found, and between the end of this row and
the mentioned outer row a short oblique series is found. Posteriorly and laterally scattered hairs are
found, and more medially an almost transverse row. The posterior marginal setae are well developed.
The oral surface of the labrum (Pl. VI fig. 14 b) shows greatest similarity to that of S. obtusifrons (PI.
VII fig. 9c). Laterally, in front, a big area with short setae is ob-
served, belonging to the marginal system. The first lateral group
consists of a few granules, and is well separated from the three fol-
lowing more or less fused groups of fairly strong setae; posteriorly
one or two groups of more delicate setae. The arrangement of the
transverse rows is seen in figure. The /amina labialis (fig. 14 c)
seems to be represented by two rounded structures meeting in the
middle; in front of it the two usual rows of setae are found. The
arrangement of the hairs behind and between the serrula 6-dentata
is seen in figure. In the middle between the labial lobes a large
group of densely placed hairs is found, which laterally is continued
into an inner marginal row of longer and a more lateral row of
shorter hairs. Independent of these, and more laterally, two rows
of short setae are found.

fg. Size of male from Thor St. 82 was 5:24 mm.; anterior
division 3°93 mm.; urosome 1°31 mm. Th.Scott’s specimens measured
ec. 4mm., Giesbrecht’s 45, Esterly’s 53 and A. Scott’s 44 mm.

The shape of the body is somewhat more slender than in

the female. The vostrwm is more slender than that of the female,
: Text-fig. 69. Scottocalanus Thorii n. sp. £3.

: é Pets: é ¢ : Ie ne a. Abdomen X15. b. Pes V dext. from
fifth thoracic tergite is fairly well marked in front, and is distinctly the tet and partly from below X 59.

rounded (text-fig. 69 a). c. Re III dext. from below. d. Pes V
: sin, Re III from the right side.

and its branches have sometimes a delicate terminal filament. The

The abdomen, which is about one third of the anterior di-
vision, has on the left side of the first somite a backwards directed, rather prominent process, in which
the genital opening is found; a fairly distinct serrated seam was found along the hinder margin of the
second to the fourth somites.

The antennulae extend to the end of the fourth abdominal somite, and are almost straight.
Segments 8~9 to 13 are more or less fused, but the articular membranes between segments 8&9 and
10, and between 12 and 13, are fairly well developed anteriorly; the segments 21 and 22 are fused on
the right side, while segments 24 and 25 are well separated on both sides. The articulation between
segments 14 and 15 is only poorly developed. Most of the bristles are soft-skinned, and very much

like sensory setae. One or two “A¥sthetasken” were found in all segments from 1—19; a proximal seta
The Ingolf-Expedition. III. 4. 28

218 COPEPODA

was found in segments 12 and x4, but not in segment 18. The Sp. of segment 24 does not extend to
the end of segment 25. The segments 8—12 are 14 as long as segments 23--25, and segment 19 is 11
as long as 23. The antennae, mandibulae and maxillulae are practically like those of the adult females.
The sensory organs of the maxillae are better developed, and the maxillipeds show the usual differences.
The xadatory legs are scarcely different from those of the females.

The f/th pair of legs is distinctly longer than the abdomen. The righ? leg (text-fig. 69 b) has
the third basipodite rounded in the usual way; inwards a short process is found, where the endopodite
is articulated; this extends distinctly beyond the end of the first outer segment, is gradually attenuated,
distally curved and here slightly hollowed. The first outer segment has several projections medially,
and is distinctly produced inwards terminally, where is the outwards convex second segment, with a
shallow excavation facing forwards and inwards; the third segment is short and somewhat attenuated
(text-fig. 69 c).

The basipodites of the /e/t leg are, as usual, long and slender; the endopodite, which extends

somewhat beyond the first outer segment, is a thin, elongated
structure with indication of segmentation in the middle, some-

O

a what enlarged terminally, and with a small terminal seta. The
left exopodite consists of two segments of almost equal length;
the second is somewhat enlarged, and is terminated with 2—3
leaf-like structures in addition to a slender hook-shaped organ
dissolved into “setae” terminally, and a plate with at least 7 long
serrations (text-fig. 69d and Pl. VIII figs 14.a—b).
The labrum etc. are in all features of interest like those
. of the female; a curious feature was, however, found in the

Text-fig. 70. Scottocalanus Thorit n. sp. arrangement of the hairs on the anterior surface, as the oblique
a. YQ (St. V). Head & 33. b. Abdomen X 33.
c. Pes V in post. view X 59. d. Yo (St. V).

Pes V X 59.

row of hairs between the two convex rows was wanting.

xe (St. V). Size of female from Thor St. 88 was 3°84 mm.;
auterior division 3:06 mm; urosome 0°78 mm. Male from St. 82 measured 3°63 mm.

The shape of the body (text-figs 70a—b) is in the main like that of the adult female, but the
frontal keel is just indicated; the fifth thoracic somite is well marked in front, and its lateral corner
is produced into a short but distinct tooth. The abdomen consists of four somites, of which the second
is longer than the first and third, which are of equal length and longer than the fourth. The first
abdominal somite has a small process on the left side; the serrated membrane of the somites II—IV
is only indicated. The appendages are, with the exception of the fifth pair of legs, like those of the
adult females as well as alike in the two sexes. In the female (text-fig. 70c) the fifth foot consists of
three distinct, almost square segments in addition to a short terminal one, produced into a short spine,
at the base of which an exterior delicate hair is found; at the base of the last segment a strong
spine is found, at least as long as the 3 distal segments. The fifth pair of the male consists of two
short basal segments in addition to the undivided branches, somewhat asymmetrical (text-fig. 70 d).

Occurrence. The Ingolf Expedition has not gathered this species, but it was taken at the
following stations by the Thor.

COPEPODA 219

In Denmark Strait
9/6 1904 St. 152 65°00 L. N. 28°10 L. W. Yt. 1000 M. Wire 1 f9.
20/5 1904 St. 153 65°27 L. N. 27°12 L. W. Yt. ? 1 f9.

In the Atlantic, south of Iceland

, 1904 St. 285 62°49 L. N. 18°46 L. W. at fi Tet S.
10/, 1904 St. 180 61°34 L. N. 19°05 L.W. Yt. 1800 M. Wire 1 f9.
™/, 1904 St. 183, 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 2 f9.
25/, 1904 St. 104 62°47 L. N. 15°03 L. W. 2£9o14 fo.

In the Iceland-Fzroe channel

79/3 1905 St. 164 61°20 L. N. 11°00 L. W. Yt. 300 M. Wire 1f¢%.

79/3 1905 St. 165 60°00 L. N. 10°35 L.W. Yt. ? 1f{9, rig.
22/, 1904 St.99 61°15 L.N. 9°35 L.W. Yt. 1700 M. Wire 1f¢.
12/, 1904 St.78 61°07 L.N. 9°30 L. W. 1 f9?.

Outside the Ingolf area

5/6 1905 St. 82 51°32 L. N. 12°03 L.W. Yt. 800 M. Wire 1 f9?, 1 y? (V).
Yt. 1200 M. Wire ro f9, rfid, 2 yo (V).
™, 1905 St. 167 57°46 L. N. 9°55 L.W. Yt. 1500 M. Wire 6f9, 1 yo (V).
8/6 1905 St.72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 5 f9, 9 fc.
20/, 1905 St. 88 48°09 L.N. 8°30 L.W. Yt. 300 M. Wire rid, 3 y?(V).

Distribution. This species is by Farran recorded as fairly common on the west coast of Ire-
land “at depths of from 330 to 1150 fathoms”; it has been recorded by the Monaco Expedition, and
from the gulf of Guinea. The records from the South Atlantic, the Pacific and the Indian Ocean cannot
be accepted.

Remarks. That the species is identical with the male of Sc. securifrons Scott and with Farran’s
S. persecans seems not to be doubtful. I think, that Farran, in contrast to Sars, is right in apply-
ing the name Sc. securifrons to the species with the pointed lateral corner, as Canu, who was the
first to rediscover the species, has done so. Farran has identified the Atlantic species with Gies-
brecht’s S. persecans, and, as will be seen in the nomenclature of Plate VI, I once thought he
was right. But on full consideration I feel obliged to follow A. Scott, and admit that S. Aersecans is
another species, and I have accordingly given the Atlantic species the name S. 7hord in appreciation
of the good work of this expedition. The female of S. Aersecans has been only imperfectly described
by Esterly, but the fifth foot seems to be somewhat different. The male of .S. Jersecans is charac-
terized “by the moderately long spines on the rami of the rostrum”, and by several structures in the

structure of the fifth foot.
28*

220 COPEPODA

ee Sn ee ees ee ee

7o. Scottocalanus securifrons Th. Scott.
(Pl. VIII figs 13 a—b; text-figs’71 a—d, 72a-—-e and 73a—d.)

1893. Q nec. d. Scolecithrix securifrons n. sp. Th. Scott. pp. | 1905. Scottocalanus acutus n. sp. G. O. Sars, p. 7.

47—48, pl. IV-—-V. | 1906,? pars. — securifrons Scott. Pearson, p. 19.
1896. Scolecithrix securifrons Scott. Canu, p. 425. | 1908. _— = — Farran, p. 57.
1898. — os — Giesbr. & Schmeil, p. 49. | 1908. Qnec. 9 Scolecithrix securifrons Scott. v. Bremen, p. 76
1903. pars. — — — Norman, p. 137- : fig. 88.
1903. — _ — J.C.Thompson, pp. 20—21. | 1909. Scottocalanus securifrons Scott. A. Scott, pp. 104—105
1904.? -- _ — Cleve, p. 197. pl. XXV figs 1—9, pl. XXVIII figs 1—9.
1904. Lophothrix — un. sp. Wolfenden, p. 120, pl. IX | IgII. pars. Lophothrix securifrons Scott. Wolfenden, p. 268.

figs 12—15.

Description. f9. Size of female from Thor St. 82 was 4:49 mm.; anterior division (to the end
of the lateral corners) 3°77 mm.; urosome 072 mm. Th. Scott’s specimens measured 4 mm. and
A. Scott’s 4°3 mm.

The crista is scarcely different from that of the preceding species, but the lateral corners are
triangularly produced into spine-like
processes, which in dorsal view are
seen to be directed somewhat outwards
(text-figs 71a—b). The rostrum has
the basal portion elongate, with paral-
lel margins; the divergent rami are
short, without distinct tooth. The ge-

nital somite is strongly swollen below,

and it is distally produced into a strong
process which overlaps the proximal

half of the following somite. Along
Text-fig. 71. Scottocalanus securifrons Th. Scott £9. the hinder margin of somites II—IV

a—b. Abdomen X15. c. Genital somite from below x 46.

d. Segments VI1—-X of the antennulae. a generally well developed serrated
seam is observed (text-figs 71 a—b).

The antennulae are like those of the preceding species, but the articular membrane between
segments 8~g and 10 are wanting posteriorly, and segments 8~9 have only one sensory seta (text-fig.
71d). The oral appendages are scarcely different from those of the preceding species.

The natatory legs are very similar to those of the preceding species, but the outer spines of
the second basipodite, as well as the inner of the third one, are comparatively longer in the second and
third pairs of legs. The second basipodite of the first pair of legs has anteriorly and outwards near
the end a rounded broad process; the Se of Re I is comparatively longer. The Se of Re I in the
second foot is distinctly pointed. The 7h pair of legs is shorter; the inner process is longer, and its
spine is longer and stronger; the outer spine is much shorter, as it does not reach the end of the
genital somite, and the inner serration consists of fewer teeth.

The structure of the /adrwm etc. is scarcely different from that of the preceding species.

fg. Size of male from Thor St. 82 was 498 mm.; anterior division 381 mm.; urosome 1°17 mm.;

Scott’s specimens measured 4°75 mm.

COPEPODA 221

The rostrum has the basal portion long and rather slender, and is divided into two rather short
branches, which each possesses a very short tooth; the whole structure is completely like Scott’s
fig. 4, Pl. XXVII. The crista is scarcely different from that of the female. The fifth thoracic tergite
has near the dorsal margin a distinct slender tooth, almost reaching the middle of the first genital somite.
The abdomen (text-fig. 72 a) is like that of the preceding species, but the lateral process of the first genital
somite is less prominent. The antennudae as well as the oral appendages are scarcely different from
those of S. Thorii (text-fig. 72 b); the zatatory legs do not differ from those of the females. The right
endopodite of pes V (text-fig. 72.c) is very short, and consists of three segments, which are indistinctly
separated; the second segment is the longest, and the third one is a short conical process bearing a
slender seta. The first outer segment is long, and distinctly widened out terminally, where it medially
possesses 3 expansions anteriorly and a single more prominent outer one posteriorly; the second outer
segment is comparatively short, and, outwards,
convex with a terminal expansion, and the third
one is short, rounded, with a single spine. The
described terminal parts of the right exopodite
form a clasping organ (text-fig. 72c—d). The
two cylindric basal segments of the Jeft leg
(text-fig. 72 e) have each a basal rounded process
as seen in figure; the third basipodite has an
inner terminal one as well. The left endopodite
consists of two segments, of which the one is

rather short and rounded with distal process, ea

while the other has two diverging processes,
XIV

of which the one is axeshaped. The /e/ exo-

podite consists of a short basal segment and :
Text-fig. 72. Scottocalanus securifrons Th. Scott f£¢.

a longer distal one, inwards excavated and a, Abdomen X15. b. Segments VII—XIV of the left antennula
culetgee Pe me fener margin of 4 eon ve pia Pig a ane Scat Hiv as
this is terminally and posteriorly densely spinous,

and anteriorly a laminous process divided into two spines is found. The third segments consists of a
rounded basal portion with a few teeth, and a much longer pointed spinelike portion (Pl. VIII figs
13 a—b).

¥g (St. V). Size of female from Thor St. 82 was 3°45 mm.; anterior division 2°80; urosome 0.65
mm. Size of female from St. 90 was 3°54 mm.

The frontal keel is less prominent than in the adult, though distinct. The lateral corner is
produced into a distinct tooth (text-figs 73 a—e). The 4th foot of the female is much shorter than in
the preceding species; the limitation between the segments is more indistinct, the third outer segment
is only represented by a short spine, and the innes spine is not as long as the three terminal segments
(text-figs 73 c—d). The //th foot of the male is characterized by a short, distinct spine in the left exo-
podite as well as by the pointed endopodite; the branches of the right side, especially the endopodite,

are distinctly more rounded.

222 COPEPODA

Occurrence. In the Atlantic, south of Iceland, the Thor has gathered this species.

9/, 1904 St. 178 63°08 L. N. 21°30 L. W. Yt. 750 M. Wire 1 f9.
tt/, 1904 St. 183 61°30 L. N. 19°05 L. W. Yt. 750 M. Wire 1 f9.
25/, 1904 St. 104 62°47 L. N. 15°03 L. W. Yt. 1800 M. Wire 1 f9.

In the Iceland-Fzroe Channel:

29/g 1905 St. 164 61°20 L. N. 11°00 L. W. Yt. 300 M. Wire 2 f9.

Outside the Ingolf area:

5/6 1905 St. 82 51°32 L. N. 12°03 L. W. Yt. 800 M. Wire 1f¢.
Yt. 1200 M. Wire 18 £9, 5 fd, 3 v2 (V).
8/, 1905 St. 72 57°52 L.N. 9°53 L.W. Yt. 1500 M. Wire 1 f?.
20/, 1905 St. 88 48°09 L. N. 8°30 L.W. Yt. 300 M. Wire 3 f92, 8fd, 1 y2(V).
21/, 1905 St.9go 47°47 L. N. 8°00 L.W. Yt. 300 M. Wire 49, 7 fd r y2(V), ry ch (V).

Distribution. This species is, according to Farran, very
characteristic of deep-water tow-nettings off the west coast of Ire-
land, most plentifully at about 700 fathoms, but it was taken at
100 fathoms. It has been recorded from the Bay of Biscay by
the Monaco Expedition, from the Gulf of Guinea, and by Wolf-
enden in the Atlantic as far south as 35° L. S. By A. Scott it

has been recorded from the Malay Archipelago.

Remarks. As this species (males, females, adult as well as
young ones) is distinguished from the preceding species by a
Text-fig. 73. Scottocalanus securifrons Th.Scott. number of important characters, viz. pointed lateral corners and

a—b. YQ (St. V). Head and first abdominal . x : :
somites X 33. c. YQ (St. V). Pes’V dext. the structure of the fifth foot, Wolfenden is certainly wrong in

in posterior view 59. d. Yo (St. V). Pes

$x regarding Scott. acutus G.O.Sars and Sc. securifrons Th. Scott
9.

(Sars) as the same species. The species, which A. Scott has
described from the Malayan Seas and referred to this species, seems in all essentials to be like the

Atlantic form.

Phaénnidae.

71. Cornucalanus chelifer Thomps.
(Pl. VII figs 4a—h, Pl. VIII figs 15 a—g).

1903? Scolecithrix chelifer n.sp, J. C. Thompson, pp. 21—22, |_ 1907. Cornucalanus chelifer Thomps. G. O. Sars, p. 27.
|e

pl. V figs 1-9. | 1908. _ — _ Farran, pp. 49 — 50.
1905. — — Farran, p. 36, pl. VII figs | 1908. Onchocalanus chelifer Thomps. v. Bremen, pp. 65 - 66,
18--19. fig. 76.

1905. Cornucalanus magnus n.sp. Wolfenden, pp. 21—22, pl. VII. | 1911. Cornucalanus magnus Wolf. Wolfenden, pp. 281—83, pl.
1906. Onchocalanus chelifer Thomps. Pearson, p. 19. | XXXII figs 1—10, text-fig. 45.

COPEPODA 223

Description. {9. Size of female from Thor St. 183 was 87 mm; anterior division 6:7 mm.; uro-
some 2mm. Wolfenden’s specimens measured 8 mm.

The head has a low terminal crista with a dorsal spine directed forwards and downwards (PI.
VIII fig. 15a). The rostrum is bifurcate with the spines directed downwards and backwards, each
bearing terminally a slender backwards curved filament. The shape of the body is like Wolfenden’s
figure; the articulation between the head and first thoracic tergite, as well as between the fourth and
fifth tergites is well developed; the lateral corners are somewhat triangularly produced, are rounded
and possess a small tooth (Pl. VII fig. 4 a).

The abdomen, which is about one third as long as the anterior division, has a serrated seam
along the hinder margin of somites II—IV; the somites, especially the genital one, are all over covered
with short hairs or spines. The genital somite, which is a little longer than deep, is distinctly pro-
duced below; the receptaculum seminis is, as seen in fig. 4a, well developed. The fifth abdominal
somite is scarcely visible from above, the comparative length between the three first somites and the
furcal branches, which are wider than long, is 35, 22, 17 and 10. The St 2, at the base of which a
dorsal tooth is seen, is almost half as long as the body and twice as long as the other setae.

The antennulae, which scarcely extend to the end-of the cephalo-thorax, consist of 24 segments.
“7M sthetasken” are found in segments 2, 3, 5, 7, 9, 12; 14, 19 and 25, as well as in segments 18 and 21,
but here representing the distal seta. A proximal seta was found in segment 12 as well as in segments
14—18. The Sp. of segment 23 is well removed from the tip of segment (!/,—*/; of its length), and
extends scarcely to the end of segment 25. The segment 21 is 1°3 as long as segment 22.

The endopodite of the aztennae is two thirds as long as the exopodite; its second segment has
8 setae in the inner lobe and 6 in the outer lobe. The manducatory part of the mandzbulae is long
and slender, with fairly well developed teeth; the third basipodite, which is about as long as wide,
has three setae inwards; the second segment of the endopodite has 9 Sp.

The Lob I of the mazxillulae is long and slender; the Li 2 has two long plumous setae, the
Li 3 has 4 setae, and the third basipodite has 4 Sa and 1 Sp. The Ri I has 3 setae, the Ri II has 3,
of which one is very delicate, and the Ri III has 4 setae. The exopodite has 10 setae and two groups
of short spines on the anterior surface; the Le has 7 4 2 setae.

The maxillae and maxillipeds have a very characteristic structure, but are scarcely different
from Wolfenden’s figure.

The frst pair of legs is like Wolfenden’s figure; the segments are broad, and the exopodite
has 3 segments with powerful outer setae; the endopodite has 3 fairly long spines on the posterior
surface; the exopodite has on the posterior surface of Re II at the base of Si five slender spines, and at
the base of Si I Re III two spines. A glandular pore is found beyond the middle in the outer margin
of Re III. The second pair of legs is like Wolfenden’s figure, but the segments are comparatively
longer; the first inner segment is produced into a fairly long, somewhat rounded, spine; the armature
of the posterior surface is scarcely different from Wolfenden’s description. The St has the serrations
almost completely fused in the distal three fourths, but only fused in the middle in the proximal fourth,
leaving a basal fenestra free. Small glandular pores were found at the base of Se Re I and II, and
at the base of Se 1 and 3 of Re III. The ¢#ird pair of legs is in main features like the fourth pair ;

224 COPEPODA

the number of glandular pores is like that of the second foot. The fourth foot is like Wolfenden’s
figure, but the armature of the posterior surface of the third outer segment differs in minor details
(Pl. VII fig. 4b); the structure of the St. is like that of-the second foot (Pl. VIII fig. 15b). The 7/7
pair of legs (fig. 4.c) consists of three segments, bearing a few hairs posteriorly; the terminal segment
is rather slender, attenuated, and produced into a rather short terminal spine.

The lateral outline of the /adrwm etc. is rather characteristic, as seen in fig. 15a; a well devel-
oped efistoma densely covered with about 40 long setae on each side was found; the /abrum proper
is densely covered with setae, the arrangement of which is similar to that seen in fig. 5e, though
differing in details; anteriorly a group of rather short setae (about 3 deep) is found; this group is on
each side continued into a large group of long setae, placed laterally and posteriorly, extending towards
the hinder margin, where groups of shorter setae are found. In the area in front of the mentioned
groups a median group of fairly long setae is observed.

The oral surface of the labrum (fig. 4d) is rather characteristic. Laterally, in front, an almost
transverse row of rather short setae is found; behind this a longitudinal row of setae is observed. In
the middle, on each side, 3—4 almost completely fused groups of densely placed, fairly long, setae are
found, In the middle, around the median circular spots, areas of short spines or granules are found.
The lamina labialis seems to be wanting, but the serrula 6-dentata is well developed (Pl. VII fig. 4 e);
in front, a median wide and elongated group of fairly long setae is found, as well as.a lateral rounded
one. Between the serrulae and behind, 2 groups of setae are found. The arrangement of the densely
placed hairs on the labial lobes and on the area behind was not studied in details, but shows great
similarity to that of O. magnus (fig. 5 e). :

£3. Size of male was 617 mm.; anterior division 4°95 mm.; urosome 1°22 mm.

The head is rounded, without any frontal crista or spine (fig. 15d). The rostrum is strong, with
short terminal filaments. The lateral corners are rounded, without any spine (Pl. VII fig. 4 f).

The abdomen is only one fourth as long as the anterior division; along the hinder margin of
somites II—IV a marginal serrated seam is found; the fifth abdominal somite is almost rudimentary; the
comparative length of the first four abdominal somites and the furcal branches is 8, 20, 15, 10 and 5.

The antennulae extend to the end of the cephalo-thorax; the two first segments are inflated
and much more powerful than those following; they contain 24 segments, but the articulation between
8~9 and ro and between 12 and 13 is wanting posteriorly. “A{sthetasken” are found in the following
numbers, I in segment 1, 4 in segment 2, 2 in segments 3—8~9, and a single one in segments 10—19,
22 and 25. The mensurements are scarcely different from those of the females. The antennae are like
those of the female, while the mandibulae differ from those of the femaie by the much wider third
basipodite with three short setae medially.

The maxillulae differ from those of the female by the rudimentary setae of the Li I and the
two short setae of Li II. The maxdllae are very similar to those of O. créstatus (Pl. VII fig. 6c), but
the spine of lob. IV is comparatively stronger, being longer, though less powerful, than that of lob. V;
the number of the setae is scarcely different from that of the female; the sensory setae of the endo-
podite have a rather curious structure, with a more or less prominent, rather short, terminal filament

surrounded by short delicate dentations. The maxillipeds are widely different from those of the females,

COPEPODA 225

especially on account of the wanting strong spines of the endopodite; the dentation of the third basi-
podite is not better developed than in related species; the fourth lobe of the second basipodite has
two short setae in addition to the spine.

The watatory legs are scarcely different from those of the female. The fifth pair of legs is not
unlike Wolfenden’s description, but his right foot corresponds to the left one in my specimens (PI.
VII figs 4f-g). The right foot (fig. 15 e) consists only of three segments and a short terminal tooth.
The left leg consists of 5 long proximal segments, in addition to a fairly short, attenuated and hairy
third outer segment, which has a short terminal seta (fig. 4g).

xg (St. V). Size of female from Thor St. 183 was 63 mm.; anterior division 51 mm.; urosome
12mm. Size of male 64 mm.

The shape of the body is like that of the adult female, but the lateral corner is more pointed
(fig. 151); the abdomen consists of four somites, the comparative length of which was 10, 19, 14, 8
and 5. The appendages, except the fifth feet, are in the young female like those of the adult females
(Pl. VII fig. 4h), this pair is even less developed than that of the adult, as seen in the drawing; in the
male each leg consists of four segments, and the left leg is considerably longer than the right one; about
the arrangement of hairs and setae I refer to fig. 15 g.

Occurrence. The Thor has in Denmark Strait once gathered this species viz:
19/6 1904 St. 152 65°00 L. N. 28°10 L. W. Yt. 200 M. Wire 1 f?.
In the Atlantic, south of Iceland:
to/, 1904 St. 180 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 1 £9, ricoh.
™/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 31 £9, 6 fo, 3 y?2(V), 4 yc (V).
In the Iceland-Fzeroe Channel:
2/; 1904 St. 78 61°07 L. N. 9°30 L. W. 3 f9.
In the Atlantic, south west of the Feeroes:
8/g 1905 St. 72 57°52 L.N. 9°53 L. W. Yt. 1500 M. Wire 4 f9.

Distribution. According to Farran “this species is of frequent occurrence in deep-water tow-
nettings off the west coast of Ireland”, at depths of from 330 to 1150 fathoms. By the Gauss it was
taken 9/,. near the Cape Verde Islands, and "/,; it was taken about 35° L.S. 05° L. E.

Remarks. In spite of minor differences I do not doubt that this species is identical with Cor-
nucalanus magnus Wolf.; Wolfenden refers Thompson’s Sc. chelifer to a different species on account
of a wanting frontal spine; as Thompson’s description of a young male is so very imperfect, I prefer
to follow Farran and Pearson.

72. Onchocalanus magnus Wolfenden.
(Pl. VII figs 5a—g; Pl. VIII figs 16 a—d).

1906? Xanthocalanus magnus n. sp. Wolfenden, pp. 32—33, | IgII? Onchocalanus frigidus n. sp. Wolfenden, pp. 276
pl. X. | —277.

1908? - _ Wolf. Wolfenden, p. 37, pl. ge _ magnus Wolf. Wolfenden, pp. 275
VII figs 1-9. | —276, pl. XXX.

The Ingolf-Expedition. III, 4. 29

226 COPEPODA

Description. Size of female from Thor St. 183 was 83 mm.; anterior division 6:5 mm.; urosome
18mm. Wolfenden’s specimens measured 88 mm.

The body is rather elongated; the head (fig. 5 a) is well raised, with distinct eyes, but without
trace of frontal keel or spine. The rostrum (Pl. VIII fig. 16a) is bifurcate, with fairly long, slightly
divergent spines, one of which, at least, possesses a slender filament. The lateral corner is triangularly
produced, and has a well marked pointed tooth, which in some specimens, however, is only indicated,
but is generally most distinct on the right side.

The abdomen (PI. VII fig. 5b) is scarcely one third as long as the anterior division; the genital
somite is rather suddenly produced below; the genital opening is more broad than long, and is placed
in the middle of a densely hirsute area; the lateral margins are somewhat overlapping and pointed in
front; an elongated receptaculum seminis is found. The anal somite is scarcely visible from above; the
comparative length of the three first abdominal somites and the furcal branches is 32, 22, 16 and 11.
The marginal serrated seam along the hinder margin of segments 2—4 is only poorly developed.

The somites are more or less hirsute, especially ventrally; the first somite has the hairs more
distinct, especially dorsally in front, where a pad of densely placed hairs is found.

The antennulae reach almost to the end of the body and consist of 24 segments the appendages
are scarcely different from those of C. chelifer; the Sp. of segment 24 is one third removed from the
end of the segment, and is far from reaching the tip of the segment 25. The segments 21 and 22 are
of almost equal length. The exopodite and the endopodite of the aztennae are of almost equal length;
the mandibulae and maxillulae are in main features like those of C. chelifer. The basipodite of the
maxillae is first strongly excavated and then distinctly produced; the lobe 1 has 5 setae, the lobes
2—4 have 3 setae; the posterior seta of the fourth lobe is stronger than the preceding setae, but much
weaker than the strong curved spine of the fifth lobe, at the base of which 3 fairly long and slender
setae are found. The endopodite has 6 brush-shaped sensory organs in addition to a long slender one.
The maxillipeds show great similarity to those of C. chelifer; the comparative length between the
main divisions is 18, 29 and 15. The first and second basipodites are like those of C. chelifer; the third
basipodite is about 6 times as long as wide, with the three proximal setae well separated from each other;
and inwards and basally with an area of densely placed delicate spines. The second segment of the endo-
podite has one short serrated curved spine and two long ones; the third segment has two similar spines.

The frst pair of legs is like that of the preceding species, but the segments are much more
slender. The second pair of legs is like those of the preceding species, but is distinctly more slender;
the third outer segment is about twice as long as wide, and as long as the terminal spine. The outer
spine of the first inner segment is fairly long and somewhat obtuse; on the anterior surface of the second
inner segment_a small pore surrounded by slender hairs is found; indistinct glandular pores were only
found in Re II and at the base of Se 3 Re III. On the posterior surface of the two inner segments
coronas of spines were found, while larger and smaller prickles were found in numbers in the outer
segments. The third pair of legs differs from the following pair by the comparatively longer and
thicker teeth, especially in the endopodite. The fourth pair of legs has marginal setae in the second
basipodite; a glandular pore is observed in the second outer segment; the posterior surface is covered

with groups of short prickles or fairly long setae, with all intermediary steps between; the setae are

COPEPODA 227

comparatively shorter in the two outer segments. Anteriorly, hairs are only found in the second basi-
podite, where, f. inst., laterally a large group of long setae is found.

The f/th pair of legs (fig. 5d) consists of three segments; the exopodite has a terminal and two
outer spines; the anterior surface is almost smooth, while the posterior surface as well as the sides
are covered with long setae.

In front of the rather prominent labrum proper a prominent efzs/oma (Pl. VII fig. 5 a), which is
densely covered with long bristles (fig. 5), is found; the bristles of the labrum are neatly arranged into two
anterior groups of long bristles, about three lateral groups of shorter hairs and a single marginal row.
The oral surface of the labrum (fig. 5 f) is anteriorly densely covered with a number of short minute
prickles; scarcely distinguished from these, two lateral groups of hairs are found, probably corresponding
to two groups in C. chelifer. Almost in the middle, on each side, about three almost completely fused
groups of short bristles as seen in figure are found, and more behind, an oblique group of delicate
hairs is found. In the middle densely placed granules are found in transverse areas. No distinct
lamina labialis is found; in front of the serrula 6-dentata (fig. 5 g) a large inner group of short granules
is found, and an outer longitudinal row of fairly long hairs, Behind, a horse-shoe shaped group of
granules is found on each side and, well separated from this, as seen in fig. 5 e, irregularly placed short
hairs. Along the inner margin of the labial lobes inwards short spines, and more outwards long bristles,

are found.

Y? (St. Vv). Size of female from Thor St. 183 was 6:25 mm.; anterior division 5 mm.; urosome
125 mm,

The shape of the body is scarcely different from that of the adult, but for the regularly pointed
lateral corner. The comparative length of the four abdominal somites and the furcal branches is 10,
15, 13, 8 and 6, The abdominal somites are almost completely smooth. But for the comparatively

shorter fifth foot, the appendages are scarcely different from those of the adult females.

Occurrence. The Thor has taken this species at two stations.

m1/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 2 £9, 2 y? (V).
8/6 1905 St.72 57°52 L.N. 9°35 L.W. Yt. 1500 M. Wire 1 y? (V).

Distribution. This species has previously been found in the Antarctic Seas.

Wolfenden has originally given the name X. magnus to a species about 88 mm. long with
pointed lateral corners. Later on he has subdivided his original species into a smaller one with rounded
lateral corners to which he applies the name O. magnus, and a larger one which he names O. /rigidus.
I think the name magnus must necessarily be used for the bigger species.

I am very doubtful, if my North Atlantic species is really identical with the Antarctic one; Wolf-
enden’s description, however, is in several important points too incomplete to settle the question.

The differences are the following. In my specimens the first as well as the fifth thoracic
somites are well marked in front; the genital somite is not as long as the following three somites,
the vulva has no “lateral flap” on each side, and the genital somite can scarcely be called “very swollen

ventrally”. The antennulae are longer, as they reach distinctly beyond the middle of the genital
29*

228 COPEPODA

somite. The Li 2 of the maxillulae has 2 not 3 setae. The Ri 2 of the fourth foot has no “corona of
spines”, but a number of fairly long bristles, and the fifth feet seem to be somewhat different.

73. Onchocalanus cristatus Wolf.
(Pl. VII figs 6a—e; Pl. VIII figs 17 a—f).

1904. Xanthocalanus cristatus n. sp. Wolfenden, p. 119, pl. 1908. Onchocalanus cristatus Wolf. Farran, p. 49.

IX figs 18—19. | 1908. Xanthocalanus cristatus Wolf. Wolfenden, p. 34.
1905. Onchocalanus trigoniceps n. sp. G. O. Sars, p. 20. | 1908. — — — v. Bremen, p. 62 fig. 70.
1906. Xanthocalanus cristatus Wolf. Pearson, p. 20. 1909? Onchocalanus cristatus Wolf. A. Scott, pp. 82—83, pl.
1906? —_ similis n. sp. Esterly, pp.68—69, pls g—13. | XXXIV figs 1-8.
1907. Onchocalanus cristatus Wolf. G. O. Sars, p. 3. | git. — - — Wolfenden, pp. 277—278.

Description. f£9. Size of female from Thor St. 183 was 815 mm.; anterior division 645 mm.;
urosome 1°70. Another specimen measured 7°5 mm. Wolfenden’s specimen measured 5°5 mm., Sars’s
7mm. and Scott’s 66 mm. A

The shape of the body is like that of O. magnus, but it is more slender; the first as well as
the fifth thoracic somite is well marked out in front. The head (Pl. VIII fig. 17 a) is well raised, and
surmounted with a dorsal low crest, visible in dorsal as well as in lateral view. The rostrum consists
of a basal portion and two fairly long somewhat divergent spines without distinct terminal filament.
The lateral corners are triangularly produced and terminated with a distinct tooth.

The abdomen is a little more than one fourth as long as the anterior division; the genital)
somite is like that of O. magnus, but is less produced below. The comparative length of the abdominal
somites and the furcal branches is 28, 18, 13 and 6; the somites are hairy in a similar way as in
the other species.

The antennulae are like those of O. magnus, and extend about to the end of the furca; the
only difference is found in the slightly different measurements of the segment 13, which is 124 (not
14) as long as segment 12, and of segment 24 which is rr as long as segment 23 (not a little shorter).
The antennae, mandibulae and maxillulae are scarcely different from those of O. magnus. The maxillae
are like those of the preceding species; the endopodite possesses in addition to a short seta of usual
structure a long slender sensory seta and 5 fairly long ones, the slightly enlarged part of which is
more or less “brush-shaped”. The maxzllipeds are like those of the preceding species, but the third
outer segment has 4 instead of 3 strong curved spines. The /rs¢ pair of legs differs only by rather
unimportant details in the armature of the posterior surface. The Se of the first inner segment is
long, slender, and distinctly pointed in the second pair of legs. The ¢hird as well as the fourth pair
of legs differs from O. magnus in the details of the arrangement of the hairs, and by the curiously
contorted terminal spine. The //¢A pair of legs consists of three segments, of which the third, attenuated
one, is longer than the second, but shorter than the two basal ones combined; it has, as seen in fig.
6a Pl. VII, a terminal and two outer spines. The anterior surface is smooth, while the sides as well
as the posterior surface are all over covered with fairly strong setae or spines.

The /abrum (Pl. VIII fig. 17a) etc. are not in any features of great interest different from the

corresponding organs of the preceding species.

COPEPODA 229

fg. Size of male was 65 mm.; anterior division 5°07 mm.; urosome 1°43 mm.

The body is more slender than in the female; the head shows trace of a crista, especially in
dorsal view. The lateral corners are rounded and possess a small, well marked tooth.

The abdomen is fairly slender (Pl. VII fig. 6b) and is, as seen in figure, beset with hairy spots.
The comparative length of the first four abdominal somites and the furcal branches is 25, 55, 45,
28 and 15.

The antennulae extend about to the end of the body; the proximal 7 segments are more
powerful than in the female. The segments 8~9 to 13 are posteriorly indistinctly separated, as the
articular membrane is sometimes missing; the segments 20 and 21 are, on the right side, partly fused;
the appendages are scarcely different from the male of C. chelifer. The antennae scarcely differ from
those of the female, but the mandibulae differ by the wide third basipodite with three rather short
inner setae; the maxzllulae are more soft-skinned than in the female; the Li 1 has 8 short setae, but
the number of setae is in other respects like that of the female. The maxillac (fig. 6c) is a soft-skinned
organ of somewhat similar shape to that of the female; the number of setae in the lobes is seen in figure;
the endopodite has 7 sensory setae, differing from rather clumsy ones basally to more slender ones distally.

The maxillipeds are distinctly more robust than in the females; the comparative length between
the main divisions is 34, 34 and 15, the setae of the second basipodite, especially the sensory one in
the middle, are less developed; the strong curved setae of the endopodite are represented by rather
weak setae.

The zatatory legs are scarcely different from those of the female. The 7/¢/ pair of legs extends
almost to the end of the abdomen. The rzgh¢ leg is much shorter than the two first segments in the
left leg (cf. Pl. VII fig. 6b), and it forms an outward convexity; the outer margin of the second seg-
ment is slightly convex, and somewhat spinous; the third segment is indistinctly divided into two
parts, and has at least a terminal and an outer rather weak spine as well as a number of stiff hairs
terminally on the posterior surface. The /e/t /eg has two long cylindric basal segments, of which the
distal one is much the longer; the second segment is convex outwards, and here possesses terminally
about 7 stiff hairs. The exopodite consists of three segments, decreasing in length as well as in
thickness from the first towards the third; the third segment (Pl. VIII fig. 17 e) is somewhat attenuated
and hairy, and is in possesion of a short terminal spine.

The epistoma (P1. VIII fig. 17 c) is well developed, with two rows of long setae; the /adrum proper
has, anteriorly, a well developed projection, but is posteriorly rather soft-skinned, with undulated lines
in the chitin; anteriorly 2—4 rows of long bristles are found; posteriorly, rows of short bristles were
observed; the marginal row of hairs was apparently wanting. The ora/ surface of the labrum is not un-
like that of the female, but the granulation in front is wanting; three well separated lateral groups
of hairs were found on each side. In the middle, just behind the third median circular spot, a single
transverse group of short bristles was found. In front of a well developed serrula 6-dentata with
short teeth, a median elongated group with two longitudinal rows and, laterally, a single convex row
were found. The labial lobes are well developed, with short marginal bristles; between the lobes a

small pointed process is found on each side.

230 COPEPODA

Y? (St. V). Size of female from Thor St. 183 was 615 mm.; anterior division 4°99 mm.; urosome
25 mm.

The shape of the body is more slender than in the adult female. Short, but distinct rostral,
filaments were found in the examined specimen. The comparative length of the abdominal somites
and the furcal branches is 30, 50, 40, 20 and 17; the somites are distinctly hirsute. The appendages
do not show any difference of importance, except the fifth pair of legs; this was in one specimen (St.
167) shorter than that of the adult female, and especially the last segment was less slender; in another,
however (St. 183) (fig. 17f Pl. VIII), the last segment was, as seen in figure, divided into two; as the
right and the left foot were almost quite alike, I am most disposed to regard this feature as an
abnormity and not as one characteristic of the male.

Y@ (St. IV). Size of female from Thor St. 183 was 4:36 mm.; anterior division 344 mm.; uro-
some 0°92.

The comparative length of the abdominal somites and the furcal branches is 28, 40, 40 and a7;
The. maxillulae have only g setae in the exopodite. The natatory legs show the usual differences, as
the Ri II—III and Re II—III are fused; the second to fourth pairs of legs have only 3 Se in the Re
IIeIll. The 7h pair of legs (Pl. VII 6e) is rather short and clumsy, with the first outer seta of
Re III rather indistinct.

Occurrence. The Thor has taken this species in Denmark Strait:
19/6 1904 St. 152 65°00 L. N. 28°10 L. W. 1 f9.
In the Atlantic, south of Iceland:

to/, 1904 St. 180 61°34 L. N. 19°05 L. W. Yt. 1800 M. Wire 1 y§ (V).
11/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 3 f9, 5 fd, 2 y2(V), 1 yP (IV).
2t/, 1904 St.99 61°15 L.N. 9°35 L. W. Yt. 1500 M. Wire 1 f9?.

In the Iceland-Fzeroe channel:

29/, 1904 St. 165 60°00 L. N. 10°35 L. W. Yt. tooo M. Wire 1 y@.
22/, 1904 St.gg 61°15 L. N. 9°35 L. W. Yt. 1700 M. Wire 1 £9; 1 y?(V).
4/3 1904 St. 230 63°10 L. N. 7°31 L. W. Yt. 1200 M. Wire 1 f9.

In the Atiantic, south west of the Feroes:
9/6 1905 St. 72 57°52 L. N. 9°55 L. W. Yt. 1500 M. Wire 2 £9, 3 y?(V), 2 y? (IV).

Distribution. This species has previously been recorded from the North-East Atlantic and is,
according to Farran, not uncommon off the west coast of Ireland “at depths of from 330 to 1150
fathoms”; the other records are rather doubtful.

Remarks. On full consideration I do not doubt that the females and males are rightly referred
to the same species.

My specimens differ from Wolfenden’s original description by its much larger size, and by
the maxillae, which do not possess “seven short thick brush processes”, and, from a note (1906 p. 32)
by the number of setae in the third basipodite and the endopodite of the maxillulae. It differs from
Sars’ O. trigoniceps by its size and the anteriorly well marked first thoracic tergite.

COPEPODA 231

It differs from Scott’s species from the Malay Archipelago by the less slender fifth foot
without inner spine, and by the endopodite of the maxillae, which does not possess 6 strongly brush-
shaped setae.

This species is nearly related to Esterly’s X. semilis; it differs, according to him, especially by
the four segments of the fifth pair of legs (Pl. XIII fig. 77). As the only examined female (from the
Gulf of California), which is 6:5 mm. long, is a young one of the penultimate stage, I think, although
the fifth pair of legs is completely like the four-segmented one which I have examined of the same
stage (Pl. VIII fig. 17 f), that a more detailed description is needed of specimens from this region before

settling the question.

74. Onchocalanus hirtipes G, O. Sars.
(Text-figs 74 a—i).
1905. Onchocalanus hirtipes n.sp. G. O. Sars, p. 20. 1909. Onchocalanus hirtipes G. O. Sars. A. Scott, p. 83, pl.
1908. — — G,O.Sars, Farran, p. 49. XXXIV figs 9—17.

Description. {9. Size of female from Thor St. 183 was 53 mm.; anterior division 4:0 mm.; uro-
some 1I°3 mm. Sars’ specimens measured 47 mm., Farran’s 57 and Scott’s 5 mm.

The body is moderately slender. The head is suddenly, but not very much, raised, and does
not possess any crista. The fairly long vostrwm has two only slightly divergent spines, each possessing
a long, slender terminal filament. The first as well as the fifth thoracic tergites are well marked in
front; the lateral corners are somewhat triangularly produced, but rounded (text-fig. 74 a).

The abdomen is one third as long as the anterior division; the genital somite is strongly pro-
duced below, and has a short receptaculum; in dorsal view it is seen to be much broader somewhat
in front of the middle; in front and in a less degree behind it becomes suddenly narrow. The serrated
seam along the hinder margin from the second to fourth somite is well developed. Short, stiff, scattered
hairs are found on each side of the genital somite, and tufts of fairly long hairs on the ventral surface
of the fifth somite.

The antennulae reach about to the end of the genital somite; the appendages are scarcely
different from those of C. chelifer, except the Sp. of the segment 24, which is one third removed from the
tip of the segment, and extends to the end of segment 25. The segment 13 is 16 as long as segment
12, and the segment 24 is a little longer than 23.

The exopodite and the endopodite of the aztennae are of almost equal length; the Si of the
first basipodite is as in the preceding species short. The mandibulae and maxillulae are like those of
C. chelifer, but for the presence of 11 setae in the endopodite (5 in the Ri III) of the maxillulae. The
structure of the maxillae is like that of the two preceding species; the endopodite has, in addition to
a single vermiform seta, 7 rather curiously developed “brush-shaped” setae, similar to those figured in
Scott’s fig. 14 (Pl. XXXIV). The maxillipeds are similar to those of the preceding species; the com-
parative length of its main divisions is 65, 80 and 47; the sensory setae of the second basipodite is
distinctly brush-shaped, and scarcely twice as long as wide on the left side, but on the right side it
is like that of other species; the number of curved setae in the endopodite is as in the preceding

species, but they are comparatively weaker.

232 COPEPODA

The frst pair of legs is like that of the preceding species; the Se of the Re I extends some-
what beyond the end of the Re II. The endopodite has on its posterior surface 3-+ 2 spines; the
exopodite has 5 spines at the base of Se Re I, 6 spines at the base of Si Re IJ, and near the inner
margin of Re III three groups consisting of 4, 3 and 3 spines. The endopodite of the second pair of legs
has a long pointed Se in the Re I; on the posterior surface of RiI a group of 5 fairly strong spines is
found, and in Ri II two outer rows of 6 spines and an inner one of 8 weaker spines. The terminal seta,
which is like that of the preceding species, is as long as the third outer segment; on the posterior surface
of the third basipodite and the exopodite groups of rather short spines are found; the number of glandular
pores is like that of O. magnus. The armature of the posterior surface of the third pazr of legs is like
that of the preceding species; the endopodite has 5 long spines in Ri I, a curved row of 7 long spines
and an inner group of about 20 setae in Ri IJ, and in Ri III groups of 5 strong and 12 short spines;
the exopodite has a number of short spines and
bristles. The third outer segment is, as shown in
text-fig. 73 b, curiously short, probably due to ac-
cident; a similar abnormal structure has been
described by Wolfenden in the fourth pair of legs
of the male of C. chelifer (1911 p. 283). The fourth
pair of legs has the armature. somewhat less
developed, but the third outer segment was trans-
formed in a similar way. The terminal segments
of the third and fourth pairs of legs were only
examined on the left side, as they were wanting

on the right side.

Text-fig. 74. Onchocalanus hirtipes G. O. Sars. The 4th pair of legs (text-fi peaty si
a. £9. Genital somite X 33. b. £9. Pes III Re III X59. ©. £9 Sith p 8 ( t-ligs 74.0—-€):60
Pes V sin. d—e. £9. Pes V Re III sin. et dext. X 150. f. fo. sists of three segments, which are almost com-
Abdomen X 33. g. Maxilla sin. in ant. view K 150. h. fo.

Pes Vin ait view 9p, Sade Pee das Reale pletely smooth on the anterior surface, but post-

eriorly at least in distal half of the segments, they

are covered with fairly long stiff hairs; the left leg has terminally a bifurcate process (fig. 74d), and
in the right a three-divided one (fig. 74 e) is found.

The lateral view of the /abrum etc. is like that of the preceding species; the organs were
not examined in detail in the single specimen at my disposal.

£3. Size of male from Thor St. 183 was 4:04 mm.; anterior division 3°05 mm.; urosome 0:99 mn.

The shape of the cephalosome is scarcely different from that of the female (text-fig. 74 f). The
abdomen has, as usual, five somites, but the fifth one is scarcely visible from above; the comparative
length of the four somites and the furcal branches, which are as long as wide is 25, 40, 33, 20 and
12. The distal segments of the antennulae were wanting; the proximal segments are like those of the
preceding species. The antennae, mandibulae and maxillulae show the same differences from those of
the female as in O. cristatus.

The maxiliae are in general shape like those of the preceding species (cf. Pl. VII fig. 6c); the

structure and arrangement of the 8 sensory setae in the endopodite are seen in text-fig. 74g. The

COPEPODA 233

maxtillipeds are like those of the female; the comparative length of the main divisions is 55, 65 and
32; the endopodite is somewhat shorter, and its setae are less strong. The sensory seta of the second
basipodite is three to four times as long as wide, curved, and somewhat attenuated; it is thus well
distinguished from the short one of the female, as well as from the comparatively long and straight one
of the male in O. cristatus.

The frst pair of legs differs from that of the female by the want of spines on the posterior sur-
face of the Re I, and by three spines only in Ri. The second pair of legs is scarcely different from
that of the female. The ¢hzrd pair of legs is in main features like that of the female; the third outer
segment is of usual structure, and the armature of the posterior surface is like that of O. magnus.
The fourth pair of legs was very defective.

The /f/th pair of legs, like that of O. cristatus, consists of a short right leg extending
scarcely to the end of the first segment of the left side, and of a long and slender left leg, which
extends distinctly beyond the end of the abdomen (text-fig. 74 f); the right leg has, as seen in text-fig.
74h, three fairly long and broad proximal segments in addition to a rudimentary terminal one, con-
tinued into a short spine. The left leg consists, as seen in figure, of five elongated segments like those
of O. cristatus; the third outer segment is, however, as seen in text-fig. 741, less slender, and has in
addition to the terminal seta a distal outer one.

Occurrence. The Thor has taken a male and a female of this species '™/, 1904 St. 183 61°30
L. N. 17°08 L. W. Yt. 1800 M. Wire.

Distribution. Previously a single specimen (?) has been gathered by the Monaco St. 1849, 36°17
L. N. 28°28 L. W. o—3000 M., on the west coast of Ireland (55° L. N. 10° L. W. at 1150 fathoms) and by
the Siboga at 3° L. S. 127° L. E.

Remarks. My specimens do not differ from Sars’ short description, and agree with Farran’s
specimens in the shape of the genital somite, but differ by the shape of the fifth pair of legs, which
is not “fivejointed” on the one side. From Scott’s figures they differ by minor points in the structure
of the antennulae, but especially by the third segment of the fifth foot, which has a distal Se in ad-
dition to an undivided St; as, however, the fifth foot seems to vary from the one specimen to the

other, there is not at present sufficient justification for separating the two species from each other.

75. Onchocalanus affinis n. sp.
(Text-figs 75a—e and 76a—d).

Description. {£9. Size of female from Thor St. 183 was 63 mm.; anterior division 5°09 mm.;
urosome 1I'4 mm.

The body is somewhat more slender than in the preceding species. The head is more suddenly
raised; the basal portion, which is more powerful than in the preceding species, is directed more
downwards (text-fig. 75 a). The first and the fifth tergites are only indistinctly marked in front; the
lateral corners are triangularly produced and obtusely rounded.

The abdomen (text-fig. 75b) differs from that of the preceding species by the shape of the

genital somite; dorsally the somite, somewhat in front of the middle, is rather suddenly wider than
The Ingolf-Expedition. III. 4. 30

234 COPEPODA

more anteriorly, but posteriorly it is of almost equal width. The comparative length of the three first
abdominal somites and the furca is 75, 50, 30 and 22.

The antennulae reach at least to the end of the third abdominal somite; the Sp of segment 24
is one third removed from the tip of the segment, and is far from extending to the end of segment
25; in other respects the antennulae are like those of the preceding species. The oral appendages are
scarcely different from those of O. hirtipes; the com-
parative length of the main divisions in the maxilli-
peds is 85, 100 and 57; the sensory seta of the second
basipodite is fairly long like that of O. créstatus.

The frst pair of legs differs from that of O. héirti-
pes by the number of spines; the endopodite has 4 spines;
the exopodite has no spines in Re I, 7 spines at the
base of Si Re II, and in Re III 3, 6 and 6 spines near
the inner margin. The number of spines on the posterior
surface in the second pair of legs is somewhat greater
than in O. hirtipes; the endopodite has in Ri IT 8+

: ae 6-12 spines. In the structure of the third and fourth

Text-fig. 75. Onchocalanus affinis n.sp. £9.

a. Rostrum X18. b. Abdomen X18. c. Maxilla sin. in legs no difference from the preceding species was’ ob-
anterior view X 150. d—e. Pea V sin, et dext X 59 served. ‘The Jifth pair of legs (text-figs 75 d—e) differs
from that of the preceding species by the structure of the terminal spines of Re III; in the left leg

two terminal spines in addition to a Se were found; on the right side the Se is poorly developed, but
a fairly strong Si was found. The anterior surface is, as in O. Aértipes, almost completely smooth.

fg. Size of male from Thor St. 180 was 5:19 mm.; anterior division 41 mm.; trosome 1:09 mm.
The shape of the body is like that of the preceding species; the lateral
corners are more rounded and less produced than in the female. The com-
parative length between the abdominal somites and the furcal branches is 30, , fi
45, 36, 24, 2 and 15. The axtennulae almost reach to the end of furca; they show
the usual differences from those of the female. The antennae, mandibulae and
maxillulae are scarcely different from those of the adult female. The maxzllae
differ by the structure of some of the sensory setae of the endopodite (text- /
figs 75c). The maxillipeds are like those of the preceding species, but the ; :

sensory seta is shorter than in the preceding species; the comparative length

of the main divisions is 75, 80 and 42. The xatatory legs are scarcely different Text-fig. 76.

Onchocalanus affinis n. sp. £3.
a. Pes V X18. b. Basal
The th pair of legs (text-figs 76a—b) is only in minor points dif- segments of pes V X 59.
c. Pes V Re III dext. in
posterior view 150. d. Re

from those of the female.

ferent from that of O. hirtzpes; the right leg extends somewhat beyond the
first segment of the other side. The terminal segment of the vight leg is TI ein. X 150.
somewhat bigger than in the preceding species (text-fig. 76c); the third outer segment has on the left
side, as seen in text-fig. 76d, a somewhat different shape from that of O. hertipes.

COPEPODA 235

Occurrence. The Thor has gathered 2 specimens:

tt/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 f9.
10/, 1904 St. 180 61°34 L. N. 16°05 L. W. Yt. 1800 M. Wire rig.

Remarks. It is not without some doubt that I have established a new species for the described
male and female. In spite of the variations in the fifth pair of legs, which is not uncommon to
several species, I think that the different shape of the fifth pair of legs, the larger size, and the dif-
ferent armament of the first pair of legs warrant the establishment of a new species for the female.
I think that the males of the two species are distinctly distinguishable especially by the right leg of
the fifth pair of legs. .

76. Xanthocalanus Greenii Farran.
Pl. VII figs 3a—g; Pl. VIII figs 18 a—d).
£5. 327-8

1905. Xanthocalanus Greenii n. sp. Farran, p. 39, pl. VIII figs | 1908. Xanthocalanus Greeni Farr. Farran, p. 48.

I—13. 1908. _ — — _ v.Bremen, p. 60, fig. 67.
1906. —_ — Farr. Pearson, 20. 1908. — calaminus Wolf. Wolfenden, p. 34.
1906? _ calaminus n.sp. Wolfenden, p. 34, pl. XI | 1911? Talacalanus calaminus Wolf. Wolfenden, pp. 279—281,
figs 3—5. Taf. XXXI, figs 9—12, text-figs 44a—b.

1907. — Greeni Farr. G. O. Sars, p. 13.

Description. Y% (St. V). Size of young male was 812 mm.; anterior division 669 mm.; uro-
some 1°43 mm. Farra'n’s specimen measured 60 mm. and Wolfenden’s 5°5 mm.

The anterior division is short and robust, about 4°5 as long as the abdomen. The rostrum
consists of a proximal portion, continued into 2 thin, but stiff, rather long and somewhat divergent
branches (Pl. VIII fig. 18a). The head is rounded without any trace of crest. The first thoracic tergite
is well marked in front by an articular line, which, beneath, is seen to be continued between the in-
sertion of the maxillae and maxillipeds, as is the fifth thoracic tergite, as seen in fig.18b. The lateral
corners are produced and terminated with a small tooth.

The comparative length of the abdominal somites and the furcal branches is 10, 17, 13, 7 and
15; the furcal branches are 14 as long as wide; serrated seam along the hinder margin of somite
II—III is well developed.

The antennulae extend almost to the end of body; the appendages of the 24 segments are
like those of the preceding species; the Sp. of segment 24, which was broken, was placed in the
middle of the segment; the measurements are in the main like Farran’s description. The extennae
are like Farran’s description, with two rami of about equal length. The mandibulac havea long and
slender manducatory part with rather weak teeth; the third basipodite has three long slender spines,
of which the most distal is almost twice as long as the proximal ones. The maxillulae have 7 long
powerful -++ shorter bristles in the exterior lobe; the Li I (Pl. VII fig. 3a) has 4 rather delicate Sa and
10 Sp. of which at least 8 are widened out to lancet-shaped laminae with delicate serration, as seen
in fig. 3b; the Li 2 has 4 setae, and so has Li 3, and while the third basipodite has 4 Sa-+1 Sp the
endopodite has 11 setae and the exopodite 10. The maxillae are only slightly produced posteriorly;

Lob. I has 5 setae, lobe II—III has 3 setae, and lobe IV (PI. VII fig. 3c) has a strong slightly curved

30*

236 COPEPODA

serrated spine in addition to the usual pinnate setae with laminae-formed serrated membrane; the lobe
V has two rather delicate bristles posteriorly, of which one is short, and in addition 2 very long ser-
rated membraniferous setae (figs 3c—d). The endopodite (cf. Wolfenden’s Pl. XXXI fig. 11) has 7
longer or shorter brush-shaped sensory setae as well as a long slender vermiform one. The maxillipeds
(Pl. VII fig. 3e) are in main features like those described by Farran and Wolfenden; the compara-
tive length of the main divisions is 47, 41 and 43; the first basipodite has in the middle no brush-
shaped seta, but a fairly long pointed seta; the second basipodite is distinctly twice as long as wide.
The two last setae of the segments of the endopodite are curiously developed, as shown in fig. 3f
(Pl. VII); the last segment has in addition to these two setae two simple setae and a plumous one
(not drawn by Wolfenden).

The frst pair of legs is like Sars’ figure of X. borealis, but the Se of Re I and II are short,
as seen in Farran’s fig.9; both surfaces are smooth. The second pair of legs has a short blunt Se
in the first inner segment (fig. r8c); the second inner segments possess on the posterior surface two
groups of 12 strong spines; the posterior surface of the exopodite is completely smooth; the terminal
seta is short and broad (PI. VII fig. 3g), and its teeth are only free in their terminal portion; well
developed glandular pores are found in Re I, II and III at the base of Se 3. The ¢hzrd pair of legs is
like that of the preceding pair, but the second inner segment has 9, and the third inner segment has
7 spines. The fourth pair of legs has on the posterior surface of the second inner segment 19 com-
paratively short and slender spines; on the posterior surface of the third inner segment a number of
short bristles is found.

The “th pair of legs of the examined specimen, which is probably a young male, is distinctly
different from Farran’s description of a young male, and is asymmetrical; the left smaller leg consists
as seen in fig. 18 d, of three segments; the exopodite has two outer and a terminal spine; a rudimentary
styliform endopodite is present. The right leg is somewhat longer than that of the left side, and the
endopodite as well as the exopodite has two segments.

The lateral outline of the /abrum etc. is, as seen in fig. 18a (PI. VIII), rather characteristic.

Occurrence. The Thor has in 1904 or 1905 in the Atlantic south of Iceland without locality
taken a young male of this interesting species.

This species has previously been recorded from the west coast of Ireland “at depths of from
680 to 1150 fathoms”, from the Bay of Biscay and by the Monaco Expedition.

Remarks. On full consideration I think that this species is identical with Farran’s X. Greni
in spite of the larger size and the distinct tooth of the lateral corner. It is probably also identical with
Wolfenden’s X. calaminus, though differing in the features mentioned as well as in a few others.

77. Xanthocalanus pinguis Farran.
(Pl. VII figs 2a—d, text-figs 77 a—b).

1897? Xanthocalanus hirtipes n. sp. Vanhéffen, p. 282, fig. 18. 1908. Xanthocalanus pinguis Farr. Farran, p. 48, pl. IV fig. 18.

1905. _ pinguis n.sp. Farran, pp. 39—40, pl. VIII | 1908. — = — y.Bremen, pp. 60—61, fig. 68.
—IX. 1908? — _ — Wolfenden, p. 35.

1906. = — Farr. Pearson, p. 20.

COPEPODA 237

Description. f9. Size of female from Thor St. 99 was 5:19 mm.; anterior division 4:15 mm.;
urosome 104. Farran’s specimens measured 4°5—51 mm.

The shape of the body is in the main like that of X. borealis. The first and fifth somites, but
especially the fifth, are well marked in front (text-fig. 77 a); the lateral corners are produced into a small tooth.

The abdomen, which is one fourth as long as the anterior division, has a slightly produced
genital somite, and a distinct receptaculum seminis; along the hinder margin of somites II—IV a striated
seam is found; the comparative length of the first three abdominal somites and the furcal rami is 18,
12, 9 and 8.

The antennulae extend to the end of the fourth thoracic tergite, and consist of 23 segments;
the number of “Afsthetasken” is like that of C. chelifer; a proximal seta was found in segments 12, 14,
16 and 18, but not in segments 15 and 17; the posterior seta of segment 24 is placed in the middle
of the segment, and extends just to the end of segment 25. Segment 24 is 1°2 as
long as 23, and 1°5 as long as 24, which is as long as segment 22.

The exopodite of the antennae is distinctly longer than the endopodite.
The mandibulae are scarcely different from those of X. borealis, while the maxzllulae,
especially the distal portions, are more long and slender than in X. Greeni as well
as borealis; the number, but not the shape, of setae in the maxzllulae is as in X.
Green, but the endopodite has only 9 setae. The maxillae are like Sars’ and Far-
ran’s figures; the lobe V has in addition to 3 setae, of which the two are short

and delicate, a serrated and distinctly curved spine, which is longer and stronger

than that of the fourth lobe; the endopodite has 7 brush-shaped sensory setae in Text-fig. 77. Xantho-
calanus pinguis Farr.
a. £9. Genital somite

X. borealis; the sensory seta of the second basipodite is fairly long and brush-shaped; 18. b. yo (St. V).
Abdomen x 18,

addition to a vermiform one. The maxillipeds are somewhat less slender than in

the comparative length between the main divisions is 65, 73 and 48.

The frst pair of legs is like that of X. dorealis, but the Se of Re I extends almost to the end
of Re II. The second pair of legs differs from that of X. dorealis by finer serration of St; the glan-
dular pores are like those of the preceding species. The Si of the second basipodite shows an abnormal
structure probably due to traumatism, as it is suddenly narrower and then gradually enlarged,
where it is divided into three again subdivided branches. The ¢hzrd and fourth pair of legs, the distal
segments of which were wanting, are scarcely different from those of X. borealis. The fifth pair of
legs (Pl. VII fig. 2a) is in main features like Farran’s earlier description, and is scarcely different from
the figure which Farran has given of a larger specimen (his Pl. IV fig. 18); the anterior surface is
smooth, but the posterior surface has, as shown in figure, groups of short spines.

The lateral outline of the epistoma and labrum is like that of X. Greeni, as seen in figure,
and they are not distinctly defined from each other. The epistoma has in front a group of long slender
bristles; somewhat in front of the transverse row of bristles along the posterior margin a regular
transverse series of fairly long setae is found, and just in front of this a group of irregularly placed
bristles is found; laterally two or three groups of short hairs are found.

On the oral surface of the /abrum (Pl. VII fig. 2b), in front and laterally, two oblique almost

parallel wide rows of bristles were observed; in the middle, on each side, 4 more or less fused wide

238 COPEPODA

areas of numerous short hairs or granules were observed. The chitinous framework is on each side
in front of the third median circular spot produced into a beak-like structure; somewhat behind, a
transverse chitinous bar was found in the middle. Behind the fourth median circular spot a number
of short granules was found.

In front of the indistinct /amzna labialis a large group of short hairs is observed, consisting of
an inner and outer part; the hairs decrease in size outwards. Between the serrula 6-serrata a
group of granules is observed, and behind, outer and inner groups of longer and shorter hairs, as seen
in figure 2c (Pl. VII). Along the labial lobes inwards, marginal rows of long slender setae are found
anteriorly and short spines posteriorly; behind the lobes in the middle, areas of minute granules are
found, and the lobes possess laterally groups of irregularly placed fairly long and slender bristles,
limited inwards by an oblique row of somewhat shorter hairs.

c (St. V). Size of young male was 443 mm.; anterior division 3:51 mm.; urosome o'92. An-
other young male as well as a female measured 3°77 mm.

The shape of the body differs from that of the adult by the comparatively better marked fifth
thoracic somite (text-fig. 77b), and by the abdomen, which has four somites, the comparative length
of which is 5, 13, 9, 6 and 5; the furcal rami are a little longer than wide. The 4/¢/ pair of legs in
the female is scarcely different from that of the adult; in the male (Pl. VII fig. 2d) it is distinctly
different; on the right side it differs by the two-segmented exopodite, the first segment of which has
a distinct Se, and the terminal segment of which has 2 terminal spines; the left leg shows a similar

segmentation, but is less hirsute and shows trace of segmentation in Re II.

Occurrence. The Thor has gathered this species once in the Iceland-Feroe channel and
once in the Atlantic south of Iceland.

22/, 04 St. 99 61°05 L. N. 9°35 L. W. Yt. 1700 M. Wire 29, 2 y?(V), 3y ch (V).
12/; 04 St. 78 61°08 L. N. 28° L. W. tyd (V).

Distribution. This species has been recorded from the west coast of Ireland “at a depth of
630 fathoms”. If it is identical with X. Azrtipfes Vanh. and dorealis G. O. Sars, it has a wide distribution
viz. the west coast of Ireland, the Iceland-Feroe channel, the west coast of Norway, Kara Sea and the
Arctic Ocean near the New Siberia Islands.

Remarks. That this species is identical with the species which Farran 19098 has mentioned -
as X. fimguis? seems not to be doubtful on account of its size 5:1 mm. and the almost identical shape
of the fifth pair of legs. From the typical specimens of Farran’s species (1905) it differs by the more
pointed lateral corners of the fifth thoracic tergite, and by a somewhat different measurement of the
antennulae [the segment 22 is as long as instead of 1-3 (in fig. 20 Pl. VIII the two segments are of
almost equal length) as long as segment 25], but especially by the more distinct spinulation of the
fifth pair of legs. When the variability of the fifth pair of legs is taken into consideration, I do not
doubt that the two different forms belong to the same species.

It is nearly related to X. profundus Sars (1907 p.14), which differs from it by larger size, —
62 mm., and by the somewhat different shape of the fifth pair of legs.

COPEPODA 239

From X. hirtipes and borealis, to which it is very nearly related, it seems to differ by greater
size, by comparatively shorter antennulae, which do not reach to the end of the genital somite, and
by 10 instead of 9 setae in the exopodite of the antennae.

78. Xanthocalanus claviger Th. Scott.
(Text-figs 78 a—d).

1909. Amallophora claviger n. sp. Th. Scott. pp. 124—125, pl. Ill figs 1—11, pl. IV figs 13—17.

Description. {¢. Size of male from Thor St. 183 was 4°55 mm.; anterior division 3:22; uro-
some 1°33 mm.

The shape of the body is like that of X. dorealis; the head has no crest; the rostrum is
broken but seems to be fairly long, and is directed somewhat backwards. ‘The lateral corners of

Text-fig. 78. Xanthocalanus claviger Th, Scott. fo.
a. Abdomen X 23. b. Pes V sin. Re II—III in situ from the left side « 122. c. Pes V sin. Re II—III in
ant. view 240. d. Pes V dext. in exterior view X 122.

the thorax are regularly rounded. The head and the fourth somites are almost completely fused
with the following ones. The anterior division is 24 as long as the urosome; the comparative length
of the abdominal somites are seen in the fig. 78a. The serrated seam along the hinder margins is
poorly developed. ;

The antennulae extend distinctly beyond the end of the thorax to the end of the second ab-
dominal somite. Segments 89 are only in front indistinctly separated from segments 10—12, which
are completely fused; these segments are fairly well separated from segment 13, which is well
separated from segment 14; the following segments are well separated from each other. A complete
“trithek” is found in segments 3—9; “Afsthetasken” are found in segments 10—19, but are wanting in
segments 20—24. Small proximal setae are seen in segments 12, 14, 16 and 18.

The exopodite of the antennae is 1°5 as long as the endopodite, which has 6 setae in the
outer and 8 in the inner lobe of the second segment. The manducatory part of the mandibulae is
soft-skinned and very long and slender, with delicate but distinct teeth; the third basipodite is widened

ae
t 2 A —
(BK 4, SS

\

OF THE -
UNIVERSI ry,
o OP

ae

240 COPEPODA

out and possesses 2 long Si. The maxzllulae are fairly well developed, and different from those of the
male of X. borealis; the Le has 7 long powerful as well as 2 short bristles. The Li 1 is only a little
longer than wide, and has at least g bristles, which are long, broad, somewhat lamellous and distinctly
plumous; the Li 2 has 4 short setae, the Li 3 has 4 fairly long, partly plumous setae, and the third
basipodite has 5 setae. The endopodite seems only to possess 10 setae, and so does the exopodite.
The maxillae are rather soft-skinned; the Lob. I has 4 rather slender setae, the lob. 2—3 have 3 each;
the fourth lobe has 2 slender plumous bristles and a long, broad, strongly plumous seta, and the fifth
lobe has a single shorter one of similar structure in addition to 2 fairly strong plumous setae and a very
delicate one. The endopodite has 2 vermiform setae, 5 rather slender brush-shaped ones, and a curious
globular appendage scarcely twice as long as wide, with terminal almost circular opening and striated
wall. The maxillipeds are scarcely different from those of X. borealis.

The frst and second pairs of legs are scarcely different from those of X. borealis; the distal seg-
ments of the ¢hird and fourth legs are wanting, while the proximal ones are like those of mentioned
species. The #/¢h pair of legs extends distinctly beyond the end of the abdomen; the 7zgh¢ leg is
comparatively short and somewhat convex outwards, but extends distinctly beyond the end of the
first basal segment (text-fig. 77 a, d); it consists, as seen in figure, of 4 segments, of which the last one
shows trace of further segmentation, and is terminated with a short tooth. The /e/# leg consists of
three elongated proximal segments, the comparative length of which is seen in figure; the first seg-
ment has inwards on the anterior surface a short keel (text-fig. 77 a—c). The fourth segment (Re II?)
is much shorter than the preceding ones, and is somewhat enlarged towards the middle, where a
process with two groups of about ro bristles is found; beyond this process the segment is hollowed
with a concavity facing inwards, and has about 6 setae along the outer margin, as well as a tuft of
5 more slender ones and one stronger seta terminally (text-fig. 78 b—c); apparently articulated to this
segment a short “segment” with a tuft of hairs was found. The terminal segment (Re III?) has along
the one margin in the middle 5 fairly strong spines, and terminally a hooked spine; at base of which
four moderately slender setae are observed.

Occurrence. The ‘Thor has collected a single male.
11/, 1904 St. 183 61°30 L. N. 17°08 L. W. Yt. 1800 M. Wire 1 fo.
Distribution. A few males have once been taken '7/s 1908 59°36 L. N. 7° L. W. Depth 1140 Meters.

Remarks. As far as I am able to see the male of this species, which is especially characterized
by the curious development of the left foot, is identical with Scott's Amadllophora claviger. The
somewhat laminous setae which are observed in the maxillulae and maxillae suggest some affinity to
X. Grenit; its much smaller size excludes this species.

About 20 species of Xanthocalanus have been described; to refer the described male to most
of these may be excluded, especially on account of its much greater size (4°5 mm. against 2—3 mm. for
the female). Only X. pimguds Farr. (4.5—51 mm.), X. muticus G.O. Sars (5:3 mm.) and X. profundus
G. O. Sars (62 mm.) could possibly be the females of this species. From X. pimguis it seems to be
distinguished by rounded lateral corners and longer antennulae. From X. profundus it seems to differ

in quite similar features, and from X. muticus it seems to differ by longer rostrum, by lateral corners

COPEPODA 241

rounded not “obtusément triangulaire”, by longer urosome, by shorter antennulae not “aussi longues
que le corps”. I think it is quite impossible at present to tell whether the described male ought to
be regarded as identical with any of these three species, or whether it is the male of a not yet

described female.

79. Xanthocalanus hirtipes Vanh6ffen.

1897. Xanthocalanus hirtipes n. sp. VanhGffen, p. 282, fig. 18. | 1905. Xanthocalanus borealis G. O. Sars. Farran, pp. 38—309,

1900. — borealis n.sp. G. O. Sars, pp. 49—51, pl VIII figs 14—17.
pl. XI. 1906. a — _ Pearson, p. 20.
1902, —_ — G.O.Sars. Th. Scott, pp. 452 | 1907. — — Vanh. Vanh6ffen, pp. 514—
—453,, pl. XXII figs 8—9. 517, Taf. 21, fig. 16—22.
1902. = hirtipes Vanh. Mrazek, p. 523. 1908. — — G.O.Sars. v. Bremen, pp. 58—
1903. —_ borealis G. O. Sars. G. O. Sars, p. 46, 59, fig. 66.
pl. XX XI—XXXII. — pars. _ subagilis Wolf. v. Bremen, pp. 62—63,
1904.?Qnecg — subagilis n. sp. Wolfenden, p. 118, pl. | fig. 71.
IX figs 17—32. | 1908? — borealis G. O. Sars. Wolfenden, p. 33.
1905. a borealis G. O. Sars. G. O. Sars, p. 5. | 1913. — hirtipes Vanh. Stephensen, p. 318.

Of this species I have only examined a single, very mutilated, adult female found in the con-
tents of the stomach of a Lifaris barbata from Kara Sea. I have included it in this paper partly
because it certainly belongs to the fauna of this region, and partly because a full synonymy and a
discussion of its position seem to be useful.

The lateral corners of the thorax are distinctly pointed, as in Sars’ figure Pl XXXI. The exo-
podite of the maxillulae has only 9 setae, as stated by Sars.

The 7/t/ pair of legs is most similar to that described by Vanh6ffen (Taf. 21 fig. 22), with
three terminal spines only, but the last segment is fairly well distinguished, and the hairs, especially
those of the posterior surface of the third segment as well as those of the inner surface of the first
segment, are distinctly longer. The /advwm etc. are in all main features like that of the preceding species.

To decide whether X. Airtipes and borealis really belong to the same species is somewhat dif-
ficult without specimens of both forms at disposal. The character found in the size is not of much value,
when remembering that Farran’s specimens varied from 2°5 to 3°5, that Sars’ measured 3'5, and
Vanh6ffen’s 4mm.; the characters found in the structure of the fifth pair of legs are not sufficient,
when taking into consideration the great variations which, according to Farran, exist in the structure
of this pair of legs. Vanhdéffen thought that characters could be found in the spinulation of the
posterior surface of the endopodites of the natatory legs; the differences pointed out by him are cer-
tainly due to individual variability. To define the limitations of the species within this group is
probably a task just as difficult as that which has previously been discussed with Calanus and Pseu-

docalanus.

80. Phaénna spinifera Claus.
(Pl. VII figs 1 a—c; text-fig. 79).

1863. Phaénna spinifera n. sp. Claus. p. 189, Taf. XX XI figs 1—7. | 1903. Phaénna spinifera Claus. Thompson & Scott, p. 246.

1892. — — Claus. Giesbrecht, p. 293, Taf. 5, 12, 37. | 1903. — _ — Cleve, p. 367:

1893. — — — Th. Scott, p. 81, pl. VI—VIL 1904. — - — Wolfenden, p. 111,
1898. aa -- — Giesbrecht & Schmeil, p. 50. 1904. -- _ — Cleve, p. 194.

1903. _ — — J.C. Thompson, p. 23. | 1905. a — — Wolfenden, p. 1009.

The Ingolf-Expedition. HI. 4. 31

242 COPEPODA

1905. Phaénna spinifera Claus. G. O. Sars, p. 5. | 1909. Phaénna spinifera Claus. Pesta, p. 22.

1905. = _ — Farran, p. 47. 1909. _ — — A.Scott, p. 80.

1906. — _— — Pearson, p. 21. Igil. _ — -— Wolfenden, pp. 285—286.
1908, _ =i — Farran, p. 47. 1gI2. — _ — “Pesta, -p. 24.

1998. ~ _ — vy. Bremen, p. 56 fig. 63.

Description. f9. Size of specimen from Thor St. 82 was 2.9 mm.; anterior division 242; uro-
some 048mm. Giesbrecht’s specimens measured 1'8—2-1 mm.

In some of the examined specimens the head possesses dorsally, as seen in text-fig. 79, a conical
protuberance.

The interior lobes of the maxillae are placed very near to each other, the Lob. 1 has 5 setae,
the Lob. 2 has 3, and the Lob. 3, which is very short, has probably 3 setae as well; the fourth lobe
has at least 2 setae, of which the one is comparatively strong, and distinctly curved, and the fifth
lobe has in addition to fairly strong claw-shaped setae two short slender ones; the endopodite has seven
comparatively short and thick brush-shaped setae, distally apparently fused, in addition to a long and |
slender pointed one.

The legs are scarcely different from Giesbrecht’s description. The outer margin of the third
outer segment of the frst foot has proximally to the middle a small incision and a glandular pore. On

the anterior surface of the third inner segment of the second and third pairs of legs a

minute glandular pore was found, but in the fourth pair none was seen. At the base

of the outer spine in the Re II, and at the base of Se I and III Re III, glandular

pores were found in the second pair of legs, and in the third and fourth pairs at the

base of Se Re I as well. The Ri I~ III, which are fused in the second pair of legs,

possess on the posterior surface two coronas of 8 and 6 long spines respectively, the

See ee Ri HI and III of the third pair of legs have 8 and 6 spines respectively, and the Ri II
Phaénna spini- Of the fourth pair of legs has 6 long rather weak spines.

Pe gabe sc The very short /aérvum and the elevation in front of it are only indistinctly

line of body —_— separated, and the latter is placed just behind the insertion of the antennulae; the epi-

8.
as stoma is covered by a number of longer and shorter setae; on the labrum proper a trans-

verse group of fairly short setae is found; the marginal setae are only poorly developed (Pl. VII fig. ra). — 3

The oral surface (fig. 1b) has in front 4 longer and shorter oblique groups of shorter hairs converging
towards the middle, and more posteriorly, probably composed of the three hinder, a longitudinally placed
elongated group of short hairs is found. In the middle at least three groups of very short hairs or
granules are found. The lamina labialis is only poorly developed (Pl. VII fig.1¢); in front of it a
regular granular area is found; the area behind the lamina and on the labial lobes was not studied
in details (cf. fig. rc).

fg. Size of specimen from St. 82 was 2:26 mm.; anterior division 189 mm.; urosome 037 mm.
Giesbrecht’s specimen measured 18 mm.

The anterior division did not possess a lamelliform projection, as figured and described by Gies-
brecht. No dorsal protuberance was found.

Y@ (St. V). Size of specimen from Thor St. 82 was 2°3 mm.

The only difference was found in the different structure of the abdomen.

COPEPODA 243

Occurrence. The S/S Thor has gathered a few specimens of this interesting form, viz.:
14/6 1905 St. 82 51°00 L. N. 11°43 L. W. Yt. 800 M. Wire 8 £9, 1 fd, 2 y? (V).
Yt. 1200 M. Wire 1 f9.
20/6 1905 St. 88 48°09 L. N. 8°30 L. W. Yt. 300 M. Wire 3 f9?.

This species has been recorded from the west coast of Ireland, from the mid and south Atlantic,
from the Mediterranean, the Red Sea, the Indian Ocean, the Malay Archipelago and the Pacific Ocean.
Remarks. In spite of the greater size I regard this species as identical with that described

by Giesbrecht.

I am much indebted to Mr. Norman H. Beale, who has kindly undertaken the revision of
the language of this paper, as well as to Messrs. Hendriksen, who have taken great trouble in the

reproduction of the text-figures.

3°

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*

*

246 COPEPODA

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COPEPODA 247

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— : “Liste préliminaire des Calanoides recueillis pendant etc. (I). Bull. Musée Océanograph. de Monaco Nr. 26, pp. 1—22. 1905.
-- : “Liste préliminaire’des Calanoides etc. (II)’. Bull. Musée Océanograph. Monaco. Nr. 40, pp. I—27. 1905.
— : “Notes supplémentaires sur les Calanoides de la Princesse-Alice”. Bull. de l'Institut Océanographique Nr. tor, pp.
I—27. 1907.
Scott, A.: “The Copepoda of the Siboga Expedition, part 1”. Siboga Expeditie. Monog. 29a, pp. 1—323, pl. I—LXIX. 1909.
Scott, Th.: “Report on the Entomostraca from the Gulf of Guinea collected by John Rattray”. Trans. Linn. Soc. London.
Zool. Ser. 2, Vol. VI, pp. 1—161, pl. 1—15. 1894.
— : “Notes on recent gatherings of Microcrustacea from the Clyde etc.” Seventeenth Annual Report of the Fishery Board
for Scotland. Part, III, pp. 248—271, pl. X—XIII. 1899.
— : “Report on the Marine and Freshwater Crustacea from Franz Josef Land etc”. Journ. Linn. Societ. Vol. XXVII. 1899,
pp. 60—126. pl. 3—9.
— : “Notes on Gatherings of Crustacea collected for the most part by the Fishery Steamer “Garland” etc.” Nineteenth
annual Report of the Fishery Board for Scotland; Part. III, pp. 235—281, pl. XVII—XVIII. igor. $
— : “On some Entomostraca collected in the Arctic Seas in 1898 by W. S. Bruce’. Ann. Mag. Nat. History. Vol. VIII, Series
7, PP. 337-356, pl. III—VI. got.
— : “Notes on Gatherings of Crustacea collected by the Fishery Steamer “Garland” etc.” Twentieth Annual Report of the
Fishery Board for Scotland, Part. III, pp. 447—485, pl. XXII—XXV. 1902.
— : “Observat. on Crustacea collected during the hydrographic cruises 1902—1903”. North Sea Fisheries Investigation Com-
mittee. Report of Fishery & hydrographic Investig., pp. 217—257. 1905.
— : “On some new and rare Entomostraca from the Scottish Seas”. Ann. Mag. Nat. Hist. Ser. 8, Vol. III, pp. 122—130, pl.
II—IV. 1909.
Seymour-Sewel, R. B.: “Notes on the surface-living Copepoda of the Bay of Bengal’. I and II. Records of the Indian
Museum. Vol. 12, pp. 313382, pl. XV- XXIV. 1912.
Sharpe, R. W.: “Notes on the Marine Copepoda and Cladocera of Woods Hole etc.” Proceed. United Stat. Nation. Museum.
Vol. XXXVIII, pp. 405-—436, figs 1-20. I910.
Stephensen, K.: “Gronlands Krebsdyr og Pycnogonider (Conspectus Crustacearum et Pycnogonidorum Groenlandiae)". Med-
delelser om Gronland XXII, pp. 1—479. 1913.
— : “Account of the Crustacea and the Pycnogonida, collected by etc.” Meddelelser om Gronland. LI. pp. 55—77, pL I—VIII. 1913.
Steuer, A.: “Copepoden der Valdivia-Expedition”. Zool. Anzeiger. Bd. XXVII, Nr. 19, pp. 593—598, 4 text-figs. 1904.
‘ — : “Plankton-Copepoden aus dem Hafen von Brindisi”. Sitz. der Math.-Naturw. Klasse Akad. der Wissensch. Bd. CXIX,
pp. 591—598. IgIo.
— : “Adriatische Planktoncopepoden”. l.c., pp. 1005—1039, figs I—6. I9gI0.
Streets: “Contribution to the natural History of the Hawayan etc.” Smithson. Miscell. Collect. Nr. 7. Bull. U. S. Mus. Nat.
Hist. Vol. XIII, pp. 1—172. 1877.
Thompson, J.C & Scott, A.: “On the Copepoda”. Supplementary Report VII. Report to the Government of Ceylon on
the Pearl Oyster Fisheries in the Gulf of Manaar, by W. A. Herdman, pp. 227—307, pl. I—XX. 1903.
Thompson, J.C: “Copepoda of Madeira and the Canary Islands”. Journ. Linn. Soc. London. Zool. Vol. XX, pp. 145--156,
pl. 1o—13. 1888.

*

248 COPEPODA

Thompson, J. C.: ‘Report on the Copepoda obtained by M. G. Murray etc.’ Ann. Mag. Nat. Hist. 7 Ser. Vol XII, pp. 1-36,
pl I-VI. 1903. i
Vanh6ffen, E.: “Die Fauna und Flora Grénlands”. Drygalsky: Grénland-Expedition, pp. 279—285. 1897.
-— : “Crustaceen aus dem kleinen Karajakfjord in West-Grénland”. Zool. Jahrbiich. Abteil. £ Systematik, Bd. XXV, Heft 4,
pp. 507—524; taf. 20—22. 1907. fe ; :
Wheeler, W. M.: “The Free-Swimming Copepods of the Woods Hole Region”. U. S. A. Fish Commis. Bull. for 1899, pp.
157—I92 figs I-30. Ig00. :
Williams, L. W.: “Notes on Marine Copepoda of Rhode Island”. The American Naturalist, Vol. XL, Nr. 477, pp. 639—660,
' figs 1—23.
Wolfenden, R.N.: “The Plankton of the Farde Channel and Shetlands. Preliminary notes on some Radiolaria and Cope- ©
poda”. Journ. Marin. Biolog. Associat. Vol. VI, Nr. 3, pp. 344-372, pl. I-IV. 1902.
— : “On the Copepod Subfamily Aetidiinae, with a proposed Revision of the Classification”. Report. Brit. Assoc. Belfast.
1902, pp. 263—267. 1903.
— : “Notes on the Copepoda of the North Atlantic Sea and the Farde Channel’. Journ. Marin. Biol. Associat. Vol. VII,
Nr. 1, pp. 110—146, pl. IX. 1904.
— : “Notes on the collection of Copepoda”. The Fauna and Geography of the Maladive and Laccadive Archipelagoes.
Vol. I suppl. I, pp. 989—1040, pl. XCVI—C. 1905.
— : “Plankton Studies”. Part I. Copepoda, pp. 1—24, pl. I—VII. 1905.
— : “Plankton Studies”. Part II. Copepoda, pp. 25—44, pl. VIII- XIV. 1906.
— : Crustacea “Copepoda”. National Antarctic Exped. Nat. Hist. Vol. IV, pp. 1—46, pl. I—VII. 1908. é
— : “Die marinen Copepoden der deutschen Siidpolar Expedition 1901—1903”. Deutsche Siidpolar Expedition XII. Zool. IV,
pp. 183—380, Taf. XXII—XLI, text-figs 1—82. Ig1T.

. £9.

£9.
£9.
£9.

. £2.

£9.

$e

£9.

. £9.

£9.

8

£9.
£9.
£2.
£3.

EXPLANATION OF THE PLATES.
Plate I.

Fig. 1. Calanus hyperboreus Kroyer.
Marginal setae of the labrum; > 77.
Oral surface of the labrum; > 200.
Lamina labialis etc. 1 — lamina labialis, s = serrula 6-dentata; > 200.
Lobi labiales and area behind. a—c = articular cavities of the maxillulae, maxillae and
maxillipeds; >< 44.
Fig. 2. Macrocalanus princeps Brady.
Oral surface of the labrum; x 57.
Lamina labialis and anterior surface of the lobus labialis; > 57.

Fig. 3. Megacalanus princeps Wolfenden.
Labrum, lobi labiales and area behind from below; x 24.
Oral surface of the labrum; > 77.
The lamina labialis, the lobi labiales and the right mandibula in ventral and partly anterior
view. s = serrula 6-dentata; 1 — lamina labialis; > 57.
The left maxilla; > 24.
The left second foot in anterior view. gl — glandular pores; x 24.
Se Re I pes II sin. in anterior view; 1 = lamina cribrosa; gl = glandular pore; >< 44.
The lamina cribrosa; > 280.
The left fifth foot in anterior view; x 24.
The segment 6 (VI) to segment 11 (XI) of left antennula; x 24.

Fig. 4. Rhincalanus nasutus Giesbrecht.

. YQ(V). The anterior part of the body in left view; x 24.

£9. The right side of the abdomen in abnormal specimen; x 44.

AAD
. £2.
. £g

£h.
if.
ig.
iS.
if.

The lamina labialis etc.; > 200.

The fifth foot in abnormal specimen from Thor 1905 St. 88; >< go.

The oral surface of the labrum; x 280.

The left antenna in posterior view; > 38.

The fifth foot in posterior view of specimen from Thor 1905 St. 88; > 90.

The fifth foot in posterior view of specimen (Nr. 2) from Thor 1905 St. 88; > go.
The fifth foot in posterior view of specimen (Nr. 3); >< 90.

The fifth foot of an abnormal specimen from Thor St. 88; > go.

Yo (V). The fifth foot in posterior view; x go.
Y¢ (IV). The fifth pair of legs in posterior view of specimen from Thor 1905 St. 72; >< go,

The Ingolf-Expedition. III. 4. 32

250 COPEPODA

Fig. 5. Eucalanus elongatus Dana.
Fig. 5a. £9. The oral surface of the labrum; > 200.
— 5b. £9. The lamina labialis etc.; > 200.
— 5c £3 The fifth pair of legs in anterior view; > 65.
— 5d. Yo (V). The fifth pair of legs of an abnormal male; > 65.
— 5e Yo (V). The fifth foot in ant. view; > 65.
— 5f£ Yo (V). The fifth foot in ant. view; > 65.

Fig. 6. Eucalanus attenuatus Dana.
Fig. 6a. YQ (V). The oral surface of the labrum; > 200.
— 6b. Y? (V). Lamina labialis; > 200.
— 6c Yo (V). The fifth foot in post. view; > 77.

Fig. 7. Eucalanus crassus Giesbrecht.
Fig. 7a. £9. The coecal sac; x 44.

Fig. 8. Pseudocalanus minutus Kroyer.
Fig. 8a. £9. The oral surface of the labrum; >< 280.

Fig. 9. Clausocalanus arcuiformis Dana.
Fig.ga. £9. The head etc. from the left; > 77.
— gb. £9. The genital somite from the left; > 77.
— gc. £9. The oral surface of the labrum; x 260.
— gd. £9. The lamina labialis ete.; > 260.

Fig. 10. Spinocalanus abyssalis Giesbrecht.

Fig. 10a. £9. The oral surface of the labrum; > 260.
— ob. £9. The lamina labialis etc.; x 260.

Plate IL
Fig. 1. Aetidius armatus Boeck.
Fig. 1a. £9. First abdominal somite from the left; x 152.
— tb. f@. First abdominal somite from below; x 152.
— 1c. £9. Basipodite of pes IV sin. in posterior view; >< 152.
— id. £9. Lamina labialis ete.; x 280.

Fig. 2. Chiridius obtusifrons G. O. Sars.

Fig. 2a. £9. The labial structures; > 280.
— 2b. Yo (V). Pes V; x 77.
Fig. 3. Chiridius armatus Boeck.
Fig. 3a. £9. Pes II sin. anterior view; x 77.
— 3b. £9. Labrum—oral view. g?—g* the second and fourth groups of the lateral longitudinal series.
$+ the fourth central circular spot; x 200.
— 3c. £9. Lamina labialis and serrulae 6-dentatae; x 280.
— 3d. f9. Area labialis et postlabialis; >< 147.
— 3¢. fg. Pes V sin; the endopodite; > 280.

COPEPODA

25t

44.

. 5a.

~ 2a.

2b.

£3. Pes V sin; the last segment of the exopodite; > 280.
£3. Pes V dext; the exopodite; > 47.

¥dCV) Pes: Verse ay:

YS (IV). Pes V; > 117.

£9. Pes V in anterior view from abnormal specimen (Thor °/, 05 St. 172); > 77.
. £9. Pes V in anterior view from abnormal specimen (Thor 7/, 05 St. 173); >< 77.

£9. Pes V in anterior view from abnormal specimen (Thor *?/; 04 St. 72); >< 77.
Fig. 4. Chiridius nasutus un. sp.
£9. Pes II sin; x 77.

Fig. 5. Chiridius modestus n. sp.
£9; "Pes EI sin y2><:97;

Fig. 6. Aetidiopsis rostrata G. O. Sars.

. £9. Anterior portion of oral surface of labrum; > 280.

£9. Lamina labialis etc. partly in anterior view; > 280.

Fig. 7. Gaidius brevispinus G. O. Sars.

. £9. Rostrum, observed from below; > 200.

£9. Abdomen with spermatophore in lateral view; x 44.

. £9. Genital area; x 117.

f9. Exterior margin of maxilla sin. in post. view; >< 77.

. £9. Inner margin of basp. of left pes IV in posterior view; > 117.

£9. Labrum et labium; x 200. g? and gt the second and fourth group of the lateral longi-
tudinal series; S'—S7 the seven lateral series of hairs upon, between and behind the

labial lobes.
f{3. Inner margin of basp. of left pes IV in post. view; x 117.
yd. Pes V ant. view; x 77.

Fig. 8. Gaidius tenuispinus G. O. Sars.

. yd. Pes V ant. view; x 77.

Plate III.

Fig. 1. Gaidius brevispinus G. O. Sars.
£9. Maxillipes sin. in post. view; > 77.
£9. Maxillipes sin.; basipodite III; x 77.
£9. Pes IV sin. The basipodite in posterior view; x 152.
fg. Manducatory portion of the mandibula; x 152.
£3. The left maxillula in posterior view; =< 117.
fg. Maxillipes sin. in posterior view; x 77.

. £g. Pes I sin. in nearly anterior view; > 117.

fg. Pes V in posterior view; x 77.
fg. The terminal segment of the left pes V; > 200.
fg. The terminal segment of the right pes V; > 200.

Fig. 2. Gaidius tenuispinus G. O. Sars.
f?. The rostrum in dorsal view; > 200.
f9. The basal segments of the left antenna; x 77.

32*

COPEPODA

Fig. 7.
— 7b.

Fig. 1a.
— Ib.

f?. Maxillipes sin. Lobus IV of basipod. II in anterior view; x 152.
f9. Pes I. The terminal seta of the last segment of the exopodite; > 117.

. £9. The oral surface of the labrum; > 280.

£3. Rostral spine; x 77.

fg. Rostrum seen from below; x 200.

£3. Maxilla; > 280.

fg. Pes I. The terminal seta of the last segment of the exopodite; x 117.
£3. Re II of left pes V in exterior view sitting on the animal; > 200.
{3. Tip of Re III of left pes V; > 280.

fg. Ri of right pes V in situation, seen from the left side; > 200.

. £gh. Re Iv II of left pes V; x 77.
. fg. Pes V dext. The third segment of exopodite from inner side; x 280.

Fig. 3. Gaetanus major Wolfenden.

. £9. Setae of inner margin of basipodite II of pes IV in posterior view; > 117.
. £9. Portion of the labrum (oral view); x 280.

. £9. Lamina labialis etc. observed partly from in front; > 200.

. ff. Pes V in posterior view; >< 37.

. £h. Pes V dext.; the endopodite in anterior view; > 200.

{%. Portion of pes V in anterior view; x 200.
Pes IV sin. of stage IV in anterior view; x 77.

. Pes IV sin. of stage III in anterior view; > 77.

Fig. 4. Gaetanus minor Farran.

. £9. The abdomen seen from the left side; > 44.

Fig. 5. Gaetanus latifrons G. O. Sars.

. £9. Rostrum and frontal spine; >< 24.

. £9. Abdomen with spermatophore seen from the left side; > 24.

. £9. Setae on inner margin of basp. II of pes IV sin. in posterior view; > 117.
. £9. Oral surface of the labrum; > 280.

£9. Lamina labialis etc.; > 280.

Y¢(V). Setae on inner margin of basp. II pes IV sin. in posterior view; >< 117. -

Yo (V). Same of Yh (pes IV dext.); > 117.

Fig. 6. Gaetanus pileatus Farran.

Labrum in oral view; > 280.

Fig. 7. Gaetanus miles Giesbrecht.

The left maxillipes in anterior view; >< 77.
Setae on inner margin of basp. II of left pes IV in posterior view; > 117.

Plate IV.

Fig. 1. Euchirella rostrata Claus.

f?. Teeth along inner margin of basp. II pes IV dext. in posterior view; > 200.
£9. Labrum in oral view; > 200.

.

COPEPODA 253

{9. Lamina labialis ete; >< 200.
£9. Lobus labialis sin.; >< 117.

. {£g. Labrum, labium and manducatory portions of the mandibulae seen from beneath; > 117.

£3. The left pes I in ant. view; > 77.
fg. Pes V in ant. view; >< 44.

. fg. The distal segments of the left maxillula; > 117.

Fig. 2. Euchirella messinensis Claus.

. £9. The labrum in oral view; > 200.

f¢. Lamina labialis; >< 117.

. £9. Area labialis and lobi labiales; > 77.

Fig. 3. Euchirella curticauda Giesbrecht.
£9. Head; x 24.

. £9. Last thoracic and first abdominal somites; x 24.

£9. Labrum in oral view; x 200.

- £9. Lamina labialis etc.; >< 200.
. £9. Lobus labial sin.; x 77.

fg. The frontal portion of the head; x 44.

. £3. Abdomen in left view; x 24.
. £3. Left maxilla in post. view; > 117.

fg. Pes V in post. view; x 24.
fg. Pes V dextr. Re III; x 117.
fg. The last segment of the exopodite of the left pes V; x 200.

. £g. (signature not found on the plate, where the figure is placed to the right of 6b). The

last segments of the exopodite of the left pes V; > 117.

Fig. 4. Euchirella intermedia n. sp.

. £9. Abdomen in lateral view; x 22.
. £9. Labrum in oral view; x 117.

£9. Lobus labialis sin.; > 77.

Fig. 5. Euchirella maxima Wolf.

. £9. The frontal part of the head in lateral view; x 24.

. £9. Abdomen in lateral view; x 24.

. £9. The right lateral corner of the last thoracic somite; > 24.

. £9. The genital somite of the abdomen seen from below; x 24.
. £9. Labrum in oral view; x 77.

f9. Lamina labialis; x 77.
£9. The left lobus labialis; > 77.

. Yo. The left lateral corner of the last thoracic somite; > 24.

Fig. 6. Undeuchete superba n. sp.
fo. PesoVie S77

nid. Pes Vi dext.5-sema,

254 COPEPODA

Plate V.

Fig. 1. Undeuchete superba n. sp.
Fig. 1a. The abdomen in right view; > 13'5.
— 1b. The left lateral corner of last thoracic somite; > 44.
— 1c. Area labialis in ventral view; > 77.

Fig. 2. Undeuchete major Giesbrecht.
Fig. 2a. The labrum in oral view; > 200.
— 2b. The lamina labialis; > 200.
— 2c. fg, The endopodite of the right pes V in anterior and interior view; x 77.
— 2d. fg. The Re III of left pes V; x 77.

Fig. 3. Undeuchete minor Giesbrecht.

Fig. 3a. £9. The genital area from beneath; x 77.
— 3b. fg. The pes V in anterior view; x 33,
— 3c. fd. The endopodite and the exopodite of the right pes V in anterior and interior nd lee <a
— 3d. fg. The exopodite of the right pes V; x 24.

— 3e. £3. The endopodite of the right pes V; x 24.

— 3f. fo. The Re II—III of the left pes V; x 117.

— 3g. fo. The Re II of the left pes V; x 117.

.

Fig. 4. Chirudina streetsi Giesbrecht.
Fig. 4a. £9. The genital area from beneath; x 77.
— 4b. £9. The labrum in oral view; x 200.
— 4c. £9. The lamina labialis etc.; > 200.
— 4d. £9. The area labialis; x 77.
— 4e. th. The pes V in posterior view; > 32.
— 4f fd The 2 last segments of the left pes V in anterior and interior view; x 98.

Fig. 5. Chirudina abyssalis n. sp.
Fig. 5a. £9. The abdomen seen from the left; x 24.
— 5b. £9. The left mandibula in ant. view; x 44.
— 5c. £9. The left maxilla in post. view; x< 44.
— 5d. £9. The marginal teeth of the second basipodite of left pes IV in posterior view; > 117.
— 5e. £9. The lamina labialis ete; > 77.
— 5f £9 The area labialis; x 77.

Fig. 6. Chirudina pustulifera G. O. Sars.
Fig. 6a. £9. The abdomen in dorsal view; x 24.
— 6b. £92. The first abdominal somite in lateral view; x 24.
— 6c. f9. The genital area seen from beneath; x 77.
— 6d. £9. The labrum in oral view (anterior portion); >< 200.

Fig. 7. Chirudina notacantha G. O. Sars.
Fig. 7a. fo. The 2 last segments of the exopodite of the left pes V; > 77.
— 7b. f& The last segment of the exopodite of the left pes V from another specimen in a some-
. what ee position; x 77:

COPEPODA 255

Fig. 7 a.

— 7b

Fig. 8. Chirudina parvispina Farran.

. {gf The 2 last segments of the exopodite of the left pes V; x 77.

Fig. 9. Euchirella bitumida n. sp.

. £9. The abdomen ete. in dorsal view; > 24.
. £9. The abdomen seen from the left side; x 24.

£9. The genital somite seen from beneath; > 24.

. £9. The right maxilla in post. view; > 117.
. £9. The labrum in oral view (anterior portion); > 200.

£9. The lamina labialis; > 117.

. £9. The area labialis; 77.

Plate VI.
Fig. 1. Chirudina notacantha G. O. Sars.

. £9. Labrum; >< 147.

£9. Labium; > 147.

Fig. 2. Valdiviella insignis Farran.

. £9. Pes I sin.; outer margin of second and third outer segment in anterior view; > 77.

£9. Anterior surface of the labrum; > 77.

£9. Oral surface of the labrum; > 77.

£9. Lamina labialis and serrula 6-dentata; > 77.
£9. Labial lobes StCsb 3 77,

Fig. 3. Euchete norvegica Boeck.
£9. Oral surface of the labrum; x 147.

. £9. Lamina labialis; x 147.

. £9. Labial lobe; x 147.

. £3. Pes V sin.; second and third outer segment; > 77.
. £3. The oral surrounding in ventral view; > 147.

Y (Stage Il). Maxilla sin.; > 77.

Fig. 4. Euchete tonsa Giesbrecht.

. £9. Labrum in oral view; x 147.
. fg. Pes V sin.; second and third outer segment; > 77.

Fig. 5. Euchete glacialis H. J. Hansen.

. £9. Lamina labialis and serrula 6-dentata; x 147.

. £9. Labial lobe in ventral view; x 77.

. ff. Maxillula sin.; x 77.

. fg. Pes V sin.; second and third outer segment; x rr

Fig. 6. Euchete Farrani n. sp.

. £9. Oral surface of the labrum; > 147.

Fig. 7. Euchete Sarsi Farran.

f°. Labrum in anterior surface; >< 57.
fg. Pes V sin.; second and third outer segment; > 77.

256 COPEPODA

Fig. 8. Euchete barbata Brady.
Fig. 8a. £9. Labrum in oral view; > 77.
-— 8b. fh. Pes V sin.; second and third outer segment; > 77.

Fig. 9. Euchete Bradyi n. sp.
Fig. ga. 9. Labrum in oral view; x 77.

Fig. 10. Euchete Scotti Farran.
Fig. 10a. £9. Labrum in oral view; > 77.
— 1ob. £9. Lamina labialis and serrula 6-dentata; ~ 77.
— 10c fd. Pes V sin.; second and third outer segment; > 77.

Fig. 11. Euchete bisinuata Farran.
Fig. 11a. £9. Labrum in oral view; > 147.
— 1b. £9. Lamina labialis etc.; 147.
— 11c fd. Maxillipeds; hook-shaped seta of the second basipodite (lobe IV); > 200.
— i1d—e. {%. Pes V sin.; third and second outer segment; > 117.

Fig. 12. Euchete acuta Giesbrecht.
Fig. 12a. £9. Abdomen in lateral view; >< 44.
— 12b. £9. Labrum in oral view; > 200.
— 12c. £9. Lamina labialis and serrula 6-dentata; > 200.

Fig. 13. Euchete hebes Giesbrecht.
Fig. 13a. £9. Abdomen in lateral view; > 44.
— 13b. £9. Lamina labialis and serrula 6-dentata; >< 200.

Fig. 14. Scottocalanus Thorii n.sp. (in the plate marked persecans Gbt.)
Fig. 14a. £9. Labrum in anterior view; >< 77.
— 14b. £9. Labrum in oral view; >< 117.
— 14c £9. Lamina labialis and serrula 6-dentata; >< 117.

Plate VII.

Fig. 1. Phaénna spinifera Claus.
Fig. ra. £9. Rostrum and labrum in anterior view; >< 77.
— 1b. £9. Labrum in oral view; x 220.
— ic. £9. Lamina labialis and serrula 6-dentata; x 280.

Fig. 2. Xanthocalanus pinguis Farran.
Fig. 2a. £9. Pes V sin. in posterior view; x 77. :
— 2b. £9. Labrum in oral view; > 200.
— 2c. £9. Lamina labialis and serrula 6-dentata; > 200.
— 2d. Y¢ (Stags V). Pes V in posterior view; x 77.

Fig. 3. Xanthocalanus Greeni Farran.
Fig. 3a. Yo (V). First inner lobe of the maxillulae in posterior view; x 44.
— 3b. YS (V). Fourth seta in anterior view; x 77.
— 3c Yo(V). Maxilla; setae of fifth lobe in posterior view; x 44.

COPEPODA

— gd.

. £9. End of broken seta in fifth lobe of the maxillae; > 44.
. £9. Maxillipes sin.; >< 13°5.

f9. Last segment of left maxillipes; >< 44.

9.

Eg

2.

"2
ae

. £9. Pes II sin.; terminal seta; >< 44.

Fig. 4. Cornucalanus chelifer J. C. Thompson.

Abdomen in lateral view; >< 13°5.
Pes IV sin. in posterior view; >< 44.
Pes V dext. in posterior view; > 57.
Labrum in oral view; x 280.
Serrula 6-dentata:ete.; >< 200.

&. Abdomen in lateral view; x 13'5.

2
ay
i
oe
oe.

2.

a

2.

eres
Says
. o. Serrula 6-dentata; >< 200.

. 2 (Stage V). Pes V sin.; > 37.

+0 +0 +0 +O

+0 40 +0 40

2.
. 9.
2.

fi

. Pes III sin.; >< 24.
. Labrum in anterior view; > 117.

. Labrum; oral surface; > 117.

. Lamina labialis and serrula 6-dentata; > 117.

. & Pes V sin.; third outer segment; x 117.
. 2 (Stage V). Pes V sin. in anterior view; x 57.

Fig. 5. Onchocalanus magnus Wolfenden.
Head in lateral view; x 13°5.
Abdomen in lateral view; x 135.
Pes IV sin. in posterior view; x 44.
Pes V sin. in anterior view; > 57.
Labrum in anterior view and labial lobes; x 33.
Labrum in oral view; x 77.
Serrula 6-dentata and lobus labialis in anterior view; x 77.

Fig. 6. Onchocalanus cristatus Wolfenden.

Pes V sin.; third outer segment; x 57.
Abdomen in lateral view; >< 13'5.
Maxilla sin.; >< 44.

Fig. 7. Lophothrix frontalis Giesbrecht.

Fig. 8. Scaphocalanus magnus Th. Scott.

. Labrum etc. in lateral view; > 24.

Pes II; endopodite; > 57.
Labrum in anterior view; x 77.
Labrum in oral view; > 200.

Fig. 9. Scaphocalanus obtusifrons G. O. Sars.
Pes IV dext.; terminal seta; > 77.
Labrum in anterior view; > 77.
Labrum in oral view; > 200.
Serrula 6-dentata; > 200.

The Ingolf-Expedition. III. 4.

33

257

COPEPODA

Fig. 10a.
— rob.

er TOC.

Fig. I1 a.
— rb.

Fig. 12 a.
— 12b.
— I2¢

Fig. 13 a.

Fig. 14.
— I4b.
— I4¢
— 14d.

£9.

£9.
£9.
£9.
£9.

Fig. 10. Scaphocalanus globiceps Farran.
Labrum; oral surface; > 200.
Serrula 6-dentata; > 200.
Pes ‘Vj >< :977.-== 18d;

Fig. 11. Scaphocalanus validus Farran.
Labrum in anterior view; x 77.

. Pes V of S. globiceps Farran.

Fig. 12. Scaphocalanus robustus G. O. Sars.
Labrum in anterior view; > 200.
Labrum in oral view; > 200.
Serrula 6-dentata etc.; > 200. ’

Fig. 13. Scolecithricella minor Brady.
Serrula 6-dentata etc.; > 280. .

Fig. 14. Scolecithricella ovata Farran.

Maxilla sin. in anterior view; >< 117.

Labrum in anterior view and lobi labiales; >< 77.
Labrum in oral view; > 280.

Serrula 6-dentata etc.; >< 280.

Pl, VIII.

Fig. 1. Euchirella messinensis Claus.

Fig. 1. £3. Pes I dext. in anterior view; x 77.

Fig. 2. Euchirella curticauda Giesbrecht.

Fig.2a. do. Pes I sin. in anterior view; x 77.
— 2b. Pes II dext. in anterior view in an abnormal specimen; > 77.
— 2c. Pes V; right endopodite; > 117.

Fig. 3. Euchirella intermedia nu. sp.

Fig. 3. £9. Antenna dextra in anterior view; < 44.

£9.

. £9.
. £9,
. £9.
. £2.

ids
es

. £9.
. £9.

Fig. 4. Euchirella bitumida n. sp.
Head from the left; x 24.
Pes I sin. in anterior view; x 77.
Pes II dext.; endopodite; > 77.
Pes Ili dext.; endopodite; x 77.
The first basipodite with spines of the right and left side in posterior view; > 117.

Fig. 5. Chirudina Streetsi Giesbrecht.
Head from the left; >< 24.
Maxilla sin. in anterior view; > 117.

Fig. 6. Scaphocalanus magnus Th. Scott.

Abdomen from the left; >< 24.
Pes IV sin. in an abnormal specimen; > 44.

COPEPODA

259

.6c. £9. Pes V in posterior view in an abnormal specimen; > 77.

— 6d. fd. Pes V sin.; x 77.

Ge. fd. Pes» V dext; S< 77.
6f. Yo (V). Abdomen; x 24.
6g: Yo (V). Pes. V5->< 57:

Fig. 7. Scaphocalanus brevicornis G. O. Sars.

7a. £3. Abdomen from the left; > 24.

7b. £3. Pes V; tip of the right endopodite; x 77.

Fig. 8. Scaphocalanus obtusifrons G. O. Sars.

.8a. £9. Abdomen from the left; > 44.

8b. Pes V. Median portion of the terminal seta; > 200.
8c. fg. Abdomen from the left; >< 44.
8d. Yd (V). Pes V; x 77.
Se ve (Vv). Fes Ve ><-77.
Fig. 9. Scaphocalanus globiceps Farran.

.ga. ff. Pes V dext. in anterior view; x 77.

gb—c. fg. Pes V dext.; endopodite in anterior and lateral view; > 200.

Fig. 10. Scolecithricella minor Brady.

. 10a. Y?(V). Pes V; x 200.

1ob. Yo (V). Pes V; x 200.
Ioc. Yd (Stage V). Pes V; > 200.

Fig. 11. Scolecithricella Ingolfii n. sp.

. Ira. 9. Pes IV; third basipodite in anterior view; > 200.

11b—c. Pes V of two females in anterior view; > 200.

Fig. 12. Scolecithricella ovata Farran.

.12a, £9. Head from below; x 77.

12b. £9. Head from the side; x 77.

12c. £9. Genital somite; > 77.

mod. ty Yes V dext; > 117.

1ze. Y?(Stage V). Pes V in anterior view; > 117.
12fi Yd (Stage V). Pes V in anterior view; > 117.

Fig. 13. Scottocalanus securifrons Th. Scott.

. 13a. fg. Abdomen from the left; > 20.

13 b—c. fd. Pes V sin. in superior and inferior view; > 77.

Fig. 14. Scottocalanus Thorii n. sp.

. 14a. £g. Abdomen from the left; > 20.

14b. fd. Pes V sin; x 77.
Fig. 15. Cornucalanus chelifer J. C. Thompson.

.15a. £9. Head in lateral view; x 24.

15b. £9. Terminal setae of pes IV sin.; > 117.
15c. £9. Pes V sin.; the exopodite; x 200.

33°

COPEPODA

15 d,

15e,
15 f.
15 g.

. 16a.

16 b.
r6¢.
16d.

. 17 a.

17 b.
arc:
17d.
L7&
17 f.

. 18a,

18 b.
ie.
18d.

iS.
fg.

Head; x 24.
Pes V in anterior view; x 77.

Y?(V). Abdomen from the left; x 14.
Yo (V). Pes V in anterior view; x 57.

£9.
£9.
£9.
£9.

£9.
£9.

if.
is.
ff.

£9.

Fig. 16. Onchocalanus magnus Wolfenden.
Rostrum in anterior view; > 77.
Maxillula sin.; >< 44.
Maxilla sin.; >< 24.
Pes II; left endopodite; > 57.

Eig. 17. Onchocalanus cristatus Wolfenden.
Head from the left; > 14.
Pes II; left endopodite; x 57.
Head from the left; > 44.
Pes V dext. in anterior view; >< 77.
Pes V sin.; last segment of the exopodite; > 200.
Pes V sin.; >< 57.

Fig. 18. Xanthocalanus Greeni Farran.

Y¢?(V). Head from the left; = 14.

Y¢(V). Abdomen from the left; > 14.
Y?(V). Pes II; left endopodite; >< 44.
Y?(V). Pes V in anterior view; >< 44.

With: Copepoda I. Pl. I.

del,

1. Calanus hyperboreus Kr. 2 Macrocalanus princeps Brady. 3 Megacdlanus princeps Welt. 4. Rhinealanus nasutus bebe.
: 5. Fucalanus elongatus Dana. GE. attenuatus Dana. TE. crassus Gbt. &Pseudocalanus minutus Kr.
9 Clausocalanus areuttormis Dana. 10. Spinocalanus abyssalis abe.

With

1. Aetidius armatus Boek. 2. Chiridius obtusifrons GOS. 3 Ch armatus Boeck. 4. Ch. nasutus n. sp.

3. Ch. modestus n. sp. 6. Aetideopsis rostrata @OS. 7. Gaidius brevispinus @as. & &. tenuispinus GAS.
With det. _ ENMeMer se:

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With Copepoda I. Pl. Il.

4. Gaidius brevispinus GOS. 2, @. tenutspinus GO.3.
J. G, latifrons GAS,

With: Copepoda I. Pl. Vv.

i]

Ae

= 1. Kuchirella rostrata Cls. 2.E.messinensis cts. 3.E. curticauda Gsbt. $.#. intermedia nsp.

se JIL. lindeuchete L e
ie maxima n.sp. 6. superba rn. sp PUMller oo

: Wi Ly ae
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Myf

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&C. parvispina Farr 2 Euchirella bitumida np. LN Meller we

n. sp. 2. Ul. major Gbt. 3.U. minor Got 4. Chirudina strectst Gbt. 5. C.abyssaléis n.sp.

6. C pustulifera @08. 7. Cnotacantha Gas.

; M2 = AU Re
oe MN i .
“AE ee) ZA vis

ALlndeuchete superba

With det.

With: Copepoda TI Pl. VW.

7
nes Wavy
Pgs w\

ian.

RES ORL t

7 2. Valdiviella insignis Farr. 3 Buchate norvegica Boeck. E.tonsa Gbt.
FR glactalis Hans. 6 F Farrant nsp. 7 #E.Sarst Farr, 8 £barbata brad. 9 EF Bradyt nsp. 102 Scotti Barr.
2 Sreaieaig LE bisinuata Farr, 12h. acuta bt. 13. B.hebes Gbt. 1. Scottocalanus persecans Gbt.

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With: Copepoda I. Pl. VIL.

My
\ OW \S
REY

1Phaenna spinttera Cls. 2Xanthocalanus pinguis Farr. 3X. Greeni Harr. $. Corrucalanus chelifer Thomp.
S. Onchocalanius magrais Wolf. 6.0. cristatus Wolf 7 Lophothrix frontatis Gbt. 8. Scaphocalanus magnus Scott.
2 Sobtusitrons G08 10. S.globiceps Farr. 4.8 Validus Farr. 12. S.robustus @28.
With del. — 13. Scolectthricella minor Brad. 14.8. ovata Far. INMiller se.

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With: Copepoda I. Pl. VI.

1 Euchirella messinensis tls. 2 E. curticauda abt. 3K intermedia nsp. $F bitumida nsp. 5 Chirudina Streetsi abe.

6 Scaphocalanus magnus Scott. 78. brevicornis GOS. 8&5. obtusitrons G08. 9S globiceps Farr IO. Scolecithricella minor Brady.
DS. Ingoltii nsp. 12.8. ovata Farr 13. Scottocalanus securifrons Scott. 1y8Thorii n.sp. 1% Cornucalanus chelifer Thomp.

With del. — 16. Onchocalanus magnus Wolf, I7 0. cristatus Wolf. I8Xanthocalanus Greeni larr. LN Meller se.

pe tO] F-EXPEDITION

1895—1896,

THE LOCALITIES, DEPTHS, AND BOTTOMTEMPERATURES OF THE STATIONS

; Depth Depth Depth
a Lat. N. | Long. W. end cpg ae Lat. N. | Long. W. Rene poe ee Lat. N. | Long. W. natn phn
fathoms fathoms fathoms
I 62° 30’ 8° 21’ 132 723 24 63° 06’ | 56° 00’ 1199 2°4 45 61° 32 9° 43’ 643 4°17
2 63° 04’ 9° 22’ 262 5°3 25 63° 30’ | 54° 25’ 582 gM 4 46 Gr°:39" | 11° 26° 720 2°40
3 63° 35’ | 10° 24’ 272 0°5 63° 51" | 53°03" 136 47 61° 32’ | 13°40’ 950 | 3°23
4 GAoO7" |) ta? 12° 237 2°5 26 63° 57° | 52°41’ 34 0°6 48 61° 32’ hee II50 3°57
5 64° 40’ | 12° 09! 155 64° 37’ | 54° 24' 109 49 62°07’ | 15°07’ | 1120 | 2°91
6 63° 43’ | 14° 34’ go 7°0 27 64° 54’ | 55° 10° 393 3°8 50 62° 43’ | 15°07’ | I020 | 3°13
7 63° 13’ | 15° 41’ 600 4°5 28 65° 14’ | 55° 42’ 420°} 3°5 51 64°15’ | 14° 22’ 68 | 7°32
8 63° 56’ | 24° 40’ 136 6°o 29 65° 34’ | 54°31’ 68 0°2 52 63757" ERT 32" 420 7°87
9 64° 18’ | 27° 00' 295 5°8 30 66° 50’ | 54° 28’ 22 1°05 53 639.25, >| 15207 795 3°08
10 64° 24’ | 28° 50° 788 3°5 31 66° 35’ | 55°54’ 88 | 1% 54 63° 08’ | 15° 40’ 691 3°9
II 64% 34" | gko 12’ 1300 1°6 32 66° 35’ | 56° 38’ 318 3°9 55 63° 33’ | 15°02’ 316 5°9
I2 64° 38’ | 32°37’ | 040 0°3 33 67° 57’ | 55° 30° 35 | 0°8 56 64° 00’ | 15° 09’ 68 7°57
13 64° 47’ | 34° 33' 622 3°0 34 65° 17' 54° in 55 57 63° 37’ |’ 13° 02" 350 | 3°4
14 64° 45’ | 35°05’ 176 4°4 35 65° 16" | 55°05’ 362 3°6 58 64° 25’ | 12° 09’ 211 0°8
15 66° 18’ | 25° 59’ 330 —0°75 36 61° 50’ | 56° 21’ 1435 1°5 59 65° 00’ | 11° 16 310 |—o°r
16 65° 43' | 26° 58’ 250 6°r 37 60° 17’ | 54°05’ 1715 1°4 60 65° 0g’ | 12° 27’ 124 0°9
17 62° 49’ | 26°55 745 3°4 38 59°12’ | 51°05’ | 1870 | 1°3 61 65° 03' | 13° 06’ 55 | 04
18 61° 44’ | 30° 20’ 1135 3°0 39 62° 00’ | 22° 38’ 865 2°9 62 63° 18’ | 19° 12’ 72 7°92
19 60° 29’ | 34° 14’ 1566 Bh Oe 40 62° 00’ | 21° 36’ 845 ae8 63 62° 4o’ | 19°05’ 800 4°0
20 58° 20’ | 40° 48’ 1695 1°% 41 61° 39’ | 17°10 1245 2°o 64 62° 06’ | 19° 00’ 1041 Scr
21 58° or’ | 44° 45’ 1330 2°4 42 61° 41’ | 10°17’ 625 0°4 65 61° 33’ | 19° 00’ 1089 3°0
22 ~+| 58°10’ | 48°25’ 1845 1°¢ 43 61 er POLE 645 0°05 66 61° 33’ | 20° 43’ 1128 3-3
23 60° 43’ | 56° 00’ Plankon Net 44 61° 42’ 9° 36’ 545 4°8 67 61° 30’ | 22° 30’ 975 3°0

Depth Depth
free | Lat. N. | Long. W. ets pines rast Lat. N. | Long. W. S08 pains = Lat. N. | Long. W.
fathoms fathoms
68 62° 06’ | 22° 30’ 843 3°4 92 64° 44’ | 32°52’ 976 1°4 118 68° 27' 8° 20’
% 69 62° go’ | 22°17’ 589 3°9 93 64° 24’ | 35° 14' 767 1°46 119 67° 53' | 10° 19’
70 | 63° 09° | 22° 05’ 134 | 7°90 94 | 64°56’ | 36°19’ | 204 4°r 120 | 67°29" 11°32"
63° 46’ | 22°03’ 46 65° 31’ | 30°45’ 213 121 66° 59’ | 13°11’
.63° 12’ | 23° 04’ 197 6°7 95 | 65°14’ | 30° 39 752 2°r 122 | 66°42’ | 14° 44!
62° 58’ | 23° 28’ 486 5°5 96 65° 24’ | 29° 00’ 735 1°2 123 66° 52’ | 15° 40
62°17’ | 24° 36’ 695 4°2 97 | 65° 28’ | 27° 39° 450 5°5 124 | 67°40’ | 15° 4o’
61° 57’ | 25° 35’ 761 98 65° 38’ | 26° 27’ 138 5°9 125 68° 08’ | 16°02’
61° 28’ | 25° 06’ 829 99 66° 13’ 25° 53° 187 6°r 126 67? 29-5) 18%: 52"
61° 28’ | 26° 25° 780 4°3 100 66° 23’ | 14° 02’ 59 0°4 127 66° 33’ | 20° 05’
60° 50’ | 26° 50° 806 4° Ior 66° 23’ | 12°05’ 537. | —0°7 128 66° 50’ | 20° 02’
60° 10’ | 26° 59’ 951 3°6 102 66° 23’ | 10° 26’ 750 | —0°9 129 66° 35’ | 23°47’
60° 37° | 27° 52’ 799 4°5 103 | 66°23’ | 8°52’ 579: | —0%6 130 | 63°00! | 20° 4o'
60° 52’ | 28° 58’ 653 4°4 104 | 66°23’ | 7° 25' O57. | Ter 131 |. 63° 00' | 19° 09’
~ 80} 61° 02’ | 29° 32’ 935 4°0 105 | 65°34’ | 7°31’ 762 | —0°8 132 | 63°00’ | 17°04’
81 61° 44’ | 27° 00° 485 6°1 106 65° 34’ 8° 54’ 447. |. —0°6 133 63°14’ | 11° 24’
82 61° 55’ | 27° 28’ 824 4°r 65° 20’ 8° 4o’ 466 134 62234! 1-0? 26"
83 | 62°25’ | 28° 30° gi2 | 3°5 107 | 65°33’ | 10°28’ | 492 | —0°3 | 135 | 62°48’ | 9° 48’
62° 36’ | 26° o1’ 472 108 65° 30’ | 12°00’ 97 °F 136 63° o1’ go ir’
62° 36’ | 25°30’ 401 109 65° 29’ | 13° 25' 38 1°5 137 63° 14’ So sr,
62° 58’ | 25° 24’ 633 4°8 110 66° 44’ | 11° 33’ 781 | —o0°8 138 63° 26’ 7° 56’
63° er ash. ar" 170 III 67° 14’ 8° 48’ 860 | —o°g 139 637 36’ 7° 30°
65° 03'6 | 23° 476 76 112 67° 57’ 6° 44’ 1267 | —1°I 140 63° 29' 6° 57’
65° 02’, | 23° 56's IIo 113 69° 31’ 7° 06' 1309 | —1°0 141 63720" 6° 58’
64° 58’ | 24° 25' 76 6°9 114 | 70°36’ | 7° 29’ 773.) 50 142 | 63°07’ | 7°05’
64° 45’ | 27° 20’ 310 8°4 115 70° 50’ 8° 20! 86 oor 143 62° 58’ 7° 09!
go 64° 45’ | 29° 06’ 568 4°4 116 70° 05 8° 26’ 371 | —0°%4 144 62° 49’ Bor"
gi 64° 44’ | 31° 00° 1236 ork 117 69° 13’ 8° 23 1003. | —1°o

= kK

THE DANISH INGOLF-EXPEDITION.

HITHERTO PUBLISHED:

1899. Vol. I, Part I. 1. Report of the Voyage by C. / Wandel (1 plate) .....
2. Hydrography by Martin Knudsen (34 plates).........

f Kr. 25,00 (Sh. 30)

1900. — Part Il. 3. The deposits of the sea-bottom by O. B. Boeggild |
(7 CHAXtS) i nip vine tak ks Been PRE ee ae a coe - 800 (- 11)
4. Current-bottles by C. #. Wandel (1 plate)............ | : me

1899. Vol. II, Part I. The ichthyological results by Chr. Liitken (4 plates) ...
1899. — Part Il. On the Appendices genitales (Claspers) in the Greenland-

: é 13,00 (.- 18)
Shark, Somniosus microcephalus (Bl. Schn,), and other Sela-
chians. by Hector FE. Jangersem (6 plates). oo. a eee ss :
IgO0. — Part Ill. Nudibranchiate Gasteropoda by R. Bergh (5 plates)... - 475 (- 7)
1904. — Part IV. The North-European and Greenland Lycodine by ;
Adolf Severin Jensen (to plates)........... Meee “ia ah kas - 9,75 (-. 13)
IgI2. — Part V. Lamellibranchiata, Part I, by Ad. S. Jensen. (4 plates
and 5 -Tipures it the texby es oS Se cee ye Se eee - 800 (- 11)
1899. Vol. III, Part I. Pycnogonide by “7. Meinert (5 plates) ............... - 600(- 9)
1908. - Part II. Crustacea Malacostraca, I: Decapoda, Euphausiacea,
Mysidacea ‘by Ali /--ffansen: (5 plates) sevens cana ee ee - 800 (- 11)
1913. ~ Part HI. Crustacea Malacostraca, II: Tanaidacea by /7./. Hansen ;
62 Hla beSy 5s Wacd opto oan veed dele MN or aee Pe eae nae - 13,00 (- 18)
IQI5- _ Part IV. Copepoda I. Calanoida. Amphascandria by Car/ With.
(8: plates, 4292 textiigures):. a0, 50% scamchiees yey walt np eer - 15,00 ( - 18)
1903. Vol. IV, Part I. Echinoidea, Part I, by 7%. Mortensen (21 plates)...... - 20,00 ( - 24)
1907. — Part II. Echinoidea, Part II, by 7k. Mortensen (19 plates)..... , - 19,00 (- 23)
IgI4. — Part III. Chaetognaths by R. von Ritter-Zahony...........4.: ph ee (O50 amenane
1904." Vol. V, Part I. Pennatulida by Hector F. E. Jungersen (3 plates)....... - 650 (- 9)
IgI2. — Part II. Ctenophora by 7h. Mortensen (10 plates and 15 figures
Ih tHE SteXE) ie ay Aa ke em ee el i a net a ag - 10,50(- 4)
IQI2. — Part II. Ceriantharia by Oskar Carlgren (5 plates and 16 figures
; 11 the TERE) (foe el ens eel Se MS ceecioee. Osher Me Ee - 600(- 9)
1913. — Part IV. Zoantharia by Oskar Carilgren (7 ied and 6 figtfres
: ne the text)... i082 apn eee tees a eee ee ne ee - 7,00 (- 10)
IQI4. — Part V. Stylasteridae by Sidlias bch (e plates ads 7 figures :
sOTER ti <a <->. q 4 eas seed, em nT Cp ewe rEN Eo rer se se Soe wR me 7)
1902. Vol. VI, Part I. Porifera (Part 1), Homorrhaphide and Rete
by? Will. Lundbéeck (19: plates) a= vic bowl on age ame - 17,00 (- 22)
1905. — Partil. Porifera (Part 2), Desmacidonide: (Pars) by Will. Lundbeck
(20 plates) 55ers as those gk 2 apa tern a BR chee nS oR tans - 20,50 ( - 25)
Igol. - Part III. Porifera (Part 3), Desmacidonidee (Pars) by W7ll, Lundbeck

(12; plates) Geta ies ok ag se ee cee aslon eth cep ag tee gene: - 12,00 (- 16)

ee