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NATIONAL ANTARCTIC EXPEDITION
1901-1904

NWATURAL HISTORY

VOL. IIr.
ZOOLOGY AND BOTANY
(INVERTEBRATA: MARINE ALGAE, MUSCI)

LONDON:

PRINTED BY ORDER OF THE TRUSTEES OF
THE BRITISH MUSEUM.

1907

(All Rights Reserved)

SoLp By LoNGMANS AND Co., 39 PATERNOSTER Row, E.C.; BERNARD
DuLau AND Co., 37 SoHo SquarE, W.;
AND AT |
Tue British Museum (NaTuRAL History), CROMWELL Roan,

PRE EACE.

WueEn, in 1901, the Expedition of the 8.8. ‘ Discovery, under Captain Scott, R.N.,
was sent to the Antarctic Regions, the Trustees of the British Museum gave their
assistance to this national enterprise by allowing the cases containing the natural
history specimens which might be obtained by the Expedition to be sent to the
Natural History Museum for unpacking and sorting. They further undertook to
publish a detailed report on the collections so obtained, under the superintendence
of the Director of the Natural History Departments.

Some of the most important collections have been dealt with by naturalists who
were members of the Expedition. Thus, the Mammals and Birds are described by
Dr. Edward A. Wilson, the Isopoda and Pyenogonida by Mr. T. V. Hodgson, and
the Rocks (in relation to Field Geology) by Mr. H. T. Ferrar. Other groups have
been dealt with by members of the staff of the Natural History Departments of
the British Museum: Mr. Boulenger describes the Fishes; Mr. E. A. Smith, the
Gastropoda, Lamellibranchia, and Brachiopoda ; Mr. Jeffrey Bell, the Echinoderma ;
Dr. Calman, the Crustacea Decapoda, and the Cumacea; Mr. Kirkpatrick, the non-
calcareous Sponges; whilst Mr. G. T. Prior has prepared a petrographical description
of the Rock-specimens.

It has been necessary to obtain the assistance of other specialists in order to deal
with the rest of the collections. So far as the latter group of contributors is
concerned, the following is a list of the subject-matters, together with the name of the
naturalist who has undertaken the work in each case :—

EMBRYOS OF SEALS. : d : . Dr. Marretr Tis.
ANATOMY OF EMPEROR PENGUIN . ; . Mr. W. P. Pycrart.
TUNICATA . ; ; 5 4 . . Pror. HerpMan.
CEPHALODISCUS . ; P ; ; . Dr. Rirpewoop.
CEPHALOPODA ; : ; és . Dr. Hoyer.
NvupDIBRANCHS AND PTERGPODS i : . Sir Cwartes Extot, K.C.M.G.
POLYZOA . : ; ; A . Mr. H. W. Burrows.
Kaas anp YounG or ASTERIAS . : . Pror. MacBripe.
AMPHIPODA : : ; : ; . Me. A. O. WALKER.
SCHIZOPODA : : ; ‘ , = Mrs Horr

NEBALIZ . : ‘ . ; : . Dr. J. THrece.
OsTRACODA ; $ ; ; ; . Pror. Brapy.

COPEPODA . : F ; 4 k . Dr, WoLFENDEN.

PREFACE.

1V
CIRRIPEDIA : : F : g . Pror. GRUVEL.
MyzostoMA é ‘ : é : . Pror. v. GRAFF.
ACARI : Dr. TROUESSART.
COLLEMBOLA : : 4 : : . Pror. CARPENTER.
PoLycHA#TA . é : : ; . Prov. EHLERS.
GEPHYRIA : : 5 : : . Mr. A. BE. SHIPLey.
CHAETOGNATHA . F ; : . . Dr. Fow er.
NEMERTINES : , ‘ ; ; . Pror. Hupsrecat.
Free PLATYHELMINTHES ; : i . Me. EF. F. Larpiaw.
CEsToDA. ; : é ‘ 5 . Me. A. E. SaIPLey.
NEMATODA ; : : ! : . Dr. v. Linstow.
ZOANTHARIA ; : ; ; ; . Mr. Crusp.
ALCYONARIA AND PENNATULIDA . : . Pror. Hickson.
HyYpDROMEDUSE : : : ; . Mr. E. T. Brown.
CALCAREOUS SPONGES . : ; : . Mr. FrRewen JENKIN.
RADIOLARIA : E : : ; . Mr. Lewis H. Goven.
Mosses. : ; : ‘ . M. Jungs Carpor.
LIcHENS . : ; : F ; . Mr. DARBISHIRE.
Aaa (Marine) . : ; : . . Mrs. Gepp.
AuGa (FRESH-WATER) . : : : . Dr. Frerrsca.
Aga (CALCAREOUS) . : : ‘ . Dr. Fos.
PHYTOPLANKTON . ; : : : . Dr. Lewis H. Goven.

The work of securing the assistance of these specialists and of distributing the
collections has been performed by Mr. Jeffrey Bell, of the Zoological Department, who
has also acted as sub-editor of the Zoological and Botanical portions of the reports.
The Keeper of Minerals, Mr. Fletcher, has superintended the reports in the subjects
belonging to his department.

The Director desires to acknowledge the ability and energy which have been
brought to bear on the preparation of the Zoological reports by Mr. Jeffrey Bell.
Owing to his care, the reports have been got ready by the various contributors and
published within a reasonable time after the return of the ‘ Discovery’ from the
Antarctic Regions. Neither trouble nor expense has been spared in order to
render the illustration and presentation of the Natural History of the Expedition
worthy of the generous efforts both of Captain Scott and his fellow-explorers and
of those who provided the funds for that enterprise.

EK. Ray LANKESTER.
October, 1906.

CONDENS OR WO: i:

On Cottectine 1n Antarctic Seas. By Mr. T. V. Hopeson, F.L.S.

MOLLUSCA.

VI.—Preroropa. By Sir Cuarves Exior, K.C.M.G., LL.D.

ARTHROPODA.

(A) CRUSTACEA.

By Mr. A. O. Watxker, F.L.8. .

By Dr. J. THreLe ;

By Prof. G. S. Brapy, F.R.S.
By Prof. GRUVEL .

II].—AmpPuHIpopDa.
IV.—LEpTosTRACA.
V.—OSTRACODA.
VI.—CrrripEpIiA.
(B) PYCNOGONIDA.

T. V. Hopeson, F.L.S. .

(C) ACARI.

By Mr.

By Dr. TRovEssart
CHAETOGNATHA.
By Dr. Fow Ler
NEMATODA.
By Dr. v. Linstow

CESTODA.
By Mr. Arruor E. Surprey, F.R.S. .
COELENTERA.
I.—Atcyonarta. By Prof. Hickson, F.R.S.

IIl.—Hyproi Zoornytrs. By Prof. Hickson, F.R.S., and Mr. F.

I1].—Tenractes or A SrpHonopHoRE. By Dr. Rennie.

PORIFERA.

].—Hexactinetiipa. By Mr. R. Kirkparrick

MARINE ALGAE.
J.—PHAEOPHYCE AND FLORIDEA.
I].—CoratirnaceaE. By M. M—Fos.ir

MUSCLI.
By M. JuLes Carpor

(10 pp.)

(15 pp., 2 Pls.)

)

33. )

(Sapp: see ls)
)

Ar, Dp) LOr el)

(6 pp.; 2 Pl.)

. (6 pp., 1 Chart)

(4° pp, 2 PL)

(6 pp., 1 PL)

(5 pp., 2 Pls:)

H. GRAVELY

(34 pp., 4 Pls.)
(3 pp., 5 Figs.)

(25) pps sn els.)

By Mr. A. and Mrs. E. 8. Gepp (15 pp., 4 Pls.)

(pps) Laki¢:)

(6 pp., 2 Pls.)

ON COLLECTING IN ANTARCTIC
Slaves.
By T. V. Hopeson, F.L.S.

As the stay of the ‘Discovery’ in Winter Quarters extended over two years, it may
be of some interest to explain the principal features and conditions of the locality
where such a large proportion of the collections were made.

McMurdo Sound, as it now appears on the charts, is the channel passing between
the mainland of South Victoria Land and the large island upon which the active
voleanoes Erebus and Terror stand. The Sound is, however, converted into a true
bay by the passage across its southern extremity of that vast sheet of ice which forms
Ross’ Great Ice Barrier, and which as effectively closes it as if by terra jirma. As this
great ice sheet travels northwards past the Sound, pressure is relieved and the ice
invades the bay, but its action is checked and complicated by means of certain islands
as shown on the map issued with Vols. I. and Il. Of these, White Island is the most
important, as it lies nearly half-way between Minna Bluff and Cape Mackay,
dividing the southern opening of the Sound into two. The larger and more easterly
of the two openings is by far the most important, as the other is complicated by
the presence of Black Island. Brown Island exerts but little influence on the ice
movements of the Sound.

A tide crack separating the Barrier from the “floating” ice runs between Black
Island and the Bluff Range a little to the south of Mount Discovery. From the
south-west corner of Black Island there is a continuous if gradual rise in the ice-sheet
to a line between the south-east corner of the same island and White Island. From
this point there is a comparatively rapid descent possibly equal to, if not greater than,
the previous ascent ; the descent is accomplished in the distance of half a mile, and
there is a triple tide crack at the bottom. The mouth of the Sound from Cape Bird
to an unnamed headland on the mainland is about forty-two geographical miles
wide, and it is approximately the same distance from Cape Bird to Hut Point, under
the shelter of which the ‘Discovery’ lay. These figures were given to me by
Lieut. Armitage when we were in Winter Quarters. Subsequent observations, as
shown by the map, seem to have modified them a little.

On the 20th of January, 1902, the ‘Discovery’ passed across the mouth of
MeMurdo Sound ; it was then full of ice. The floes were of no great size and for the

VOL. III. B

2 T. V. HODGSON.

most part rectangular, massed so thickly together that it was not deemed desirable
to force the ship through them, so the voyage was continued to the eastward.
Returning on February 7, the ‘Discovery’ found the Sound full of loose ice on the
eastern side, but the western side was clear. New Harbour was examined and also
the “rough” surface of the old or permanent ice further to the southward. Then,
crossing the Sound, the ship arrived at the site of our future Winter Quarters on the
8th of February, anchoring just north of Hut Point in what is now called Arrival
Bay. Winter Harbour, to the south of Hut Point, was then full of ice, but the
position of the ship not being considered satisfactory, she was taken into it, and for
a few days lay alongside the ice face with only just enough room for her length.
At that time open water existed for some eight or nine miles to the westward of Hut
Point, but only for a few hundred yards to the southward. During the next few
days the ice went out in instalments, and on the 17th of February the harbour was
quite clear.

Cape Armitage lies a mile to the 8.8.E. of Hut Point, and may be said to form the
southern boundary of the harbour. After the ice went out, open water extended for a
distance of about four miles to the south, and for about a mile and a half to the
eastward round Cape Armitage. ‘This, we afterwards learnt, might be taken as the
approximate boundary between the fluctuating sea ice and the permanent or barrier
ice which had forced its way into the Sound from the southward, as already stated.
In proof of this it may be mentioned that on February 12th several diminutive bergs
of very irregular shape passed the mouth of the harbour on their way northward ; these
were obviously fragments from the barrier ice, and in later days, when sledging
expeditions were undertaken, it was found that the difference in level between the
barrier and sea ice was from two to ten feet, the difference increasing from east to
west, but not with any regularity. There cannot be the slightest doubt that the whole
of the ice, with the exception of the bergs already alluded to, that went out of the
Sound in the early part of 1902, was ‘“ one-year ice,” a fact proved by the condition of
the drifts against the shore, and the complete absence of pressure ridges at Pram Point.
We were not frozen in till near the end of March, and during the six weeks that we
were waiting for that event some shallow water dredging and trawling took place when-
ever a boat was available. Winter Harbour was a small bay about half a mile wide
across the mouth, and about a quarter of a mile deep. It lay at the extremity of a
spur from Mount Erebus termed the Ridgway, but this name is not an official one. This
spur was some ten miles long, and from one to three miles across ; at Winter Harbour
it was about a couple of miles wide. Within a radius of three miles round Hut Point
lay the scene of our more active operations, the whole of the western side of the Sound
being closed by reason of the ice conditions, the distance from Winter Quarters, or both
combined. The following report therefore refers more particularly to the eastern side,
which became fairly accurately known. One prominent feature of the Sound was the
so-called “ Glacier Snout,” an undulating tongue of ice connected with the Ridgway

COLLECTING IN ANTARCTIC SEAS. 3

quite close to its junction with Mount Erebus and extending seawards for some ten
miles, but nowhere more than a mile across. Its extremity was about nine miles from
Hut Point. North of this lay four small islands. These have since been named the
Dellbridge Islands. The more westerly one of these was about a mile from the Glacier
Snout, and called “Tent Island,” as close by it a camp was established when the
attempt was made to assist nature by sawing a channel for the ship through the ice.
The camp was maintained for some time after the sawing-out operations had been
abandoned, and for a short time some dredging operations were conducted among the
numerous ice cracks round the island. A bare mile to the north was Inaccessible
Island, so called on account of the difficulty of exploring it by a single individual, not
on account of its real inaccessibility. These two islands were about the same size, and
perhaps a quarter of a mile long, between 300 and 400 feet high. A couple of miles
further on, on the lowest slopes of Mount Erebus, was Skuary Point, a broad expanse of
basaltic rubble and patches of snow where the Skua, Megalestris maccormicki, bred in
large numbers. It was from this place that most of their eggs were taken for
scientific and domestic purposes. f

The shore line is not much indented, except here and there, where precipitous
cliffs are exposed. It is covered by a vertical wall of ice varying from between
two and a hundred feet in height, consequently there is no tidal zone. Access
to the shore from the sea or vice versd is in many places rendered easy by the
“drift” slopes which speedily accumulate in winter. In the neighbourhood of Cape
Royds the shore is not so precipitous, and a small tidal zone exists, consisting
of boulders and volcanic sand. This area was not explored till the relief ships
arrived in 1904, and then it was not possible to do much. Red Aleve were however
seen to be abundant.

The state of the ice in the Sound is almost entirely dependent on the weather,
and that is an efficient explanation of our failure to escape from Winter Quarters
during the summer of 1902-3. A three days’ blizzard at the beginning of May,
1902, when the ice was about two feet thick, swept every particle of it out of the
Sound, again exposing the area that was open when we arrived in February. In the
following September a gale again swept out the ice, and we had open water to well
within eight miles of Hut Point. Events of this kind are however accidental.
Large areas of the Ross Sea are known to be ice-free at irregular intervals, very
early in the season, after the return of the sun on August 23rd. Whatever the
condition of the fixed ice in the Sound, aJl through the summer the mouth is choked
at irregular intervals with fields of loose ice, brought in by wind and weather from
unknown localities, most probably from the eastward, the current setting from that
quarter. Part at least of these fields are eddied into the Sound as they are
directed northward by the trend of the coast. It is the frequent presence of these
masses of loose ice that damps down the swell that may occur in the Ross Sea, and
so retards the breaking-up of the fixed ice. During the season of 1902-3 the open

B2

4 T. V. HODGSON.

water never came within five miles of the ‘ Discovery,’ so that in the following season
its gradual approach was watched with more than ordinary interest, not to say
anxiety. On January 4th, 1904, when the relief ships arrived there were at least
eighteen miles of ice still to go; some fourteen miles went out in about six weeks,
but on February 14th the necessary conditions obtained, and four miles of fast
ice broke up and started northwards in about as many hours. At the time it
was practically a dead calm, so that the wind had no influence. When we
passed Winter Harbour for the last time, on February 18th,’ the last masses of
ice were floating out, a phenomenon which had occurred one day earlier two years
previously.

The foregoing is the briefest possible account of the ice conditions prevailing
in McMurdo Sound, and is not without biological interest, as by it the Sound may
be divided into three areas.

The first, or Northern area, extends from Cape Bird to the so-called “ glacier
toneue,” and includes the Dellbridge Islands. This is on the eastern side of the
Sound. A line drawn from the “Glacier Snout” to the southern boundary of New
Harbour forms the southern limit of this area. Open water occurs in this area for
at least four months of the year as a general rule; in the more northern part of the
area, beyond Cape Royds, the period of open water is probably much longer. This
is incontestably proved by the Penguin rookery at Cape Royds and the large
breeding place for the Skua at Skuary Point, neither of these species going far from
water except in occasional wanderings. The Penguin requires open water and a
convenient landing place, both of which were obtainable at Cape Royds; the Skua
is less dependent on either, but seeks for the former. Our presence brought immense
numbers to Hut Point, but only a few stragelers bred there; they bred in very
large numbers on the numerous islets on both sides the Sound, where the open water
was within easy reach.

The second, or Central area, includes the rest of the Sound south of the Glacier
Tongue and New Harbour, which is periodically open to navigation, rarely exceeding
a couple of months at this point, a good deal less than that south of Cape Armitage.
A small area of open water occurred under Hut Point during the summer, caused
mainly by the ice-movements in the vicinity. A large lake also appeared off
Cape Armitage, over a shoal, and was fully half a square mile in area. The
explanation of this phenomenon ultimately arrived at was that the shoal brought
the deeper and warmer waters of the Sound to the surface as the current swept
past the Cape, and so melted the ice through. This oceurred in January 1902 and
1903, and a little later in 1904. It had just frozen over when we arrived in 1902.

The third, or Southern area, is much the largest, and includes the whole of that
part occupied by the permanent or barrier ice. As the ice is covered as soon as it is
formed by a thick deposit of salt crystals and very shortly afterwards by snow, it
forms an opaque covering over the sea bottom through which no light can penetrate,

COLLECTING IN ANTARCTIC SEAS. 5

hence vegetable life to which light is essential is reduced to the minute forms
pertaining to the Plankton.

A large Laminarian was dragged up by the anchor in Arrival Bay and was
unfortunately thrown away; this was the only seaweed found within ten miles of
the ship. A quantity of red Algze was found off the shore of Tent Island, and more
again at Cape Royds. Repeated dredgings inside the 20-fathom line in Winter
Harbour produced nothing whatever in the way of seaweeds, and dragging in Arrival
Bay for Laminaria, carried out because it had once been found there, was equally
unsuccessful.

As soon as the Sound was frozen over the biological work was carried on through
holes in the ice. It was soon found that these holes had to be made large, and at the
beginning they were about six feet square. The ice taken from them had to go
somewhere, and as any irregularity of surface caused drift to accumulate, the blocks
were placed to windward and built up as a wall. In a comparatively short time this
developed into a circular shelter some fifteen feet in diameter and six to ten feet high,
having a small entrance to leeward.

As one could work in perfect comfort in these shelters all through the winter,
the work was scarcely interrupted. One had, however, to buy wisdom with experience.
At first the drift was allowed to accumulate outside against the wall, an error which
caused an immense amount of trouble, drift getting in over the top to the serious
hindrance of the work. It is absolutely imperative that the outside of such shelters
shall be kept vertical, then the bulk of the drift is kept out, as it invariably beats
back from a vertical face. As continuance of the work throughout the winter
was not expected, the routes to these shelters were not marked out, and frequently
they were very difficult to find in the dark; this occasioned a further considerable
loss of time.

After the blizzard at the beginning of May, 1902, when the ice was blown out
of the Sound and open water came to within 100 yards of the ship, advantage was
taken of the circumstance to sink 100 fathoms of line over the edge of the remaining
ice, the two ends being secured to the ice 100 yards apart. When the Sound was
again frozen over, a suitable hole was cut at each end of this line, then a light trawl
(commonly called the D net on account of the shape of its frame), and an additional
line was attached, so that the net could be hauled backwards and forwards underneath
the ice. This proved an exceedingly profitable investment till one of the ropes broke,
then operations were suspended. At intervals, however, cracks occurred in the ice
across the mouth of the Harbour, and through some of these the bight of a line was
forced for 100 yards; this came to be regarded as the practical working distance.
New holes were cut and fresh lines rove, the rest of the work proceeding as before.
This operation was not conducted without difficulty or delay from various causes.

Another serious impediment to the work of the first winter was the formation of
ice crystals on the nets and lines. At the end of May, 1902, two tow-nets were

6 T. V. HODGSON.

lowered to a depth of 6 and 7 fathoms respectively on the same line at No. 3 hole,
half a mile from the ship, the total depth of the water being 56 fathoms. Owing to
bad weather and the accumulation of drift, these nets could not be recovered for
eighteen days. It was then found that the line was thickly covered with thin plate-like
crystals of ice, of roughly hexagonal shape, and from one to four square inches in size.
The upper net of fine mesh, 150 to the inch, was similarly covered both inside and out ;
the lower net of coarse mesh, 50 to the inch, was equally thickly coated, but with
crystals of much smaller size, comparatively minute. Naturally the contents of the
nets were ruined, their prolonged stay under water would have been sufficient for that,
independently of ice crystals. The occurrence of these crystals was at first thought to
be due to the prolonged immersion of the nets. However, they occurred constantly
from this date, even in twenty-four hours’ immersion, but not so badly on the nets. It
was not suspected for some time that depth had anything to do with it, and most of
this time I was working alone, and so could not see how far these crystals extended on
the lines of the traps. However, on one occasion, Sept. 19, 1902, a trap set in 100
fathoms had been down for three days, and the crystals were measured on the line to a
depth of 17 fathoms. The line used was a quarter of an inch in diameter; with the
crystals on it, it was increased to something like a foot. Ultimately it was found that
under ordinary circumstances, 7.¢., when nets, etc., could be visited every forty-eight
hours at the outside, immersion to a depth of 10 fathoms kept the nets free, the
crystals only descending to a depth of 5-8 fathoms. This phenomenon occurred
from June to October, when the temperature of the water was 28°4° F. or — 2° C.
By October the temperature of the water had risen to 28°8° F. and the formation
of these crystals diminished, the crystals themselves becoming smaller and more
scattered, till at the end of the month they finally ceased to exist. During this month
similar crystals formed on the sides of the holes; they were easily detached, and had
to be removed before the nets could be drawn through, in order to prevent their
dropping into the net and so spoiling the contents. They disappeared about a
fortnight later. By the middle of November the surface temperature of the water
went up to 29°F. At the end of December it was 30° F., by the beginning of
February it had gone down to 29°5° F, and to 28°8° F. before the end of the month.
The annual range of the sea temperature was, therefore, less than a couple of degrees.
Various thermometers were used in these observations, and as some of them were lost
it is not possible to apply any correction for error.

The tides were irregular, but the ebb and flood occurred once in the twenty-four
hours. After two or three experiments in tide gauges one was finally rigged up on
hoard the ship. It consisted of a sounding wire attached to a heavy weight lowered to
the sea bottom, the depth being 9 fathoms. To pass through the ice the wire travelled
through a glass tube of narrow diameter, which was filled with paraffin and kept full.
The wire then passed over a pulley on board the ship, with another weight at its inner
end, and a pointer being attached the rise and fall was indicated on a scale, As the

COLLECTING IN ANTARCTIC SEAS. f

tidal observations are not, for the time being, accessible, I can only say, therefore, that
the average rise and fall was about three feet; the difference between neaps and
springs was about a foot.

The set of the current through the Sound would naturally be influenced by the
tide, but, extraordinary as this may seem, it was not noticed. A current-meter placed
two or three hundred yards to the southward of the ship, while working

g, invariably
showed a current travelling to the south-east, or around Cape Armitage. Two holes
were constantly kept open in order to obtain specimens, one of these was close to the
ship, the other about a mile and a half distant; others there were, but they were of a
more temporary nature. Up to the end of January, 1903, the current invariably
carried the lines, that depended from these holes, to the south or south-east according
to the position of the particular hole, that is, round Cape Armitage towards the
outlet of the Sound between White Island and Cape Mackay. Quite suddenly on
Feb. 2, 1903, the current was noticed setting very strongly to the northward, or exactly
opposite to the normal direction. This lasted for a few weeks, but it was not constant.
It then reverted to the normal and became constant in general direction, but not in
strength. I was unfortunately confined to my bunk during the “critical” period of
1904 and was, therefore, unable to note the change of current. If such occurred at
that period, no mention was made of it by others; just before then it had varied
considerably in strength but not in direction.

As regards the sea bottom, its composition, as far as could be ascertained, was an
exact counterpart of the land surface. The heights round Winter Harbour were
composed almost exclusively of basaltic rocks, the average elevation of which was
over 400 feet, though Crater Hill in the background was 1000 feet high. This
extremity of the Ridgway consisted of extinct craters in a more or less shattered
condition, the greater part of the rock lying in small angular lumps, with here and
there a sprinkling of boulders of very moderate dimensions, and on the lower
levels, patches of a fine gravel or coarse sand. The bottom of the Sound was the
same wherever it could be examined: angular basaltic stones everywhere, with small
patches of volcanic sand, mud and boulders of varying size near the shore. The
shoal off Cape Armitage, already alluded to, was more covered with organic débris,
chiefly polyzoa and shells; especially on its south-eastern slopes, which were rather
steep. No. 10 Hole was over this slope, a mile and a half S.S.E. from the ship in
125 fathoms.

In the north, 10 miles from Hut Point, the Dellbridge Islands rise apparently
abruptly from the bottom. The so-called ‘Glacier Snout” lay a mile nearer the ship,
and presented many peculiar features which could not be fully investigated. It is not
directly connected with Mount Erebus, and many circumstances point to its being on a
submerged ridge, but two soundings taken at the end of our stay only serve to
complicate the problem. They were taken against the Glacier Snout, half a mile from
its free end; that on the south side showed bottom at 175 fathoms, that on the north

8 T. V. HODGSON.

side 150 fathoms. It is impossible to understand how such a mass of ice, if floating,
can hold together at such an angle to the general current.

Speaking broadly, it may be said that the Sound forms a deep trench with a fairly
even bottom, the greatest depth sounded being close to the permanent or barrier ice
some four miles from Cape Armitage ; at that point, 410 fathoms, no bottom was found.

The hundred-fathom line lay about a mile from the ship and about half that
distance from Cape Armitage. My two principal holes were a mile and a half from
Hut Point, in 125 fms., one to the N.W., the other S.E. Two others, quite
two miles due west of Hut Point and not far from each other, were in 163 and
178 fms. respectively. Another hole a mile south of the Glacier Snout and eight
miles from Hut Point was in 180 fms. Numerous other soundings were taken
by Lieut. Barne within a radius of a few miles of Hut Point, but I have not yet
seen the details.

The ice reaches an average thickness of eight and a half feet in the course of a
season, and for operating under such conditions tools of a certain kind are
indispensable. After consultation with the engineer, Mr. Skelton, it was decided
that all tools should be made of mild steel, case-hardened. The effects of
temperature were not always borne in mind, and the muscular A.B. was invariably
tempted to use his tools as in temperate climates; a very slight leverage caused them
to snap, so that notwithstanding the skill of the engineering department, there was
very soon a shortage of effective instruments. Not being endowed with the
average amount of muscular strength, I did not lose my tools in this way. The
tools provided consisted of a pick, pointed at both ends, a shovel and a crowbar
termed a “pricker.” This was of iron, six feet long and about an inch in diameter,
with a chisel edge about two inches broad. These tools are essential; with regard
to the pricker, its use for any length of time makes the hands very cold, irrespective
of the amount of covering one may wear. The weight of the tool is an important
factor, and it should be maintained, though the length of the iron could be reduced to
about three feet, and a wooden stock of the same length added. As its only use is
as a stabber, the wooden stock would not be a disadvantage. As the ice thickens,
and as long as the hole is kept in trim it is only necessary to remove a slab of ice one
or two feet thick every day, but as the water is at freezing point for fully six
months of the year, the holes freeze up and close in at the sides and bottom; they
therefore have to be shaved in order to maintain their size. A tool was made for this
purpose, but the resources of the ship were not equal to making it heavy enough. It
should be a sharp chisel about 3 inches wide, and near 10 Ibs. in weight, attached to
a wooden handle 9 feet long. Another essential tool, but one readily improvised, is a
stout hook at the end of a 12-foot pole. The lines were always carefully placed in the
centre of the hole, but were invariably more or less displaced, partly by the current,
but more generally by the seals. After the ice had become 4 feet thick the lines were
frequently caught up at the lower edge of the hole and frozen in. This was a frequent

COLLECTING IN ANTARCTIC SEAS. 9

source of loss ; but if the ice could be hooked up from below before any attempt was
made to release it, the loss could be avoided. It should be borne in mind that a large
proportion of the work was done in the dark and, apart from this fact, once water
gained access to the hole, the whereabouts of the line was more or less a matter of
guesswork. Lines cannot be coiled nor wound on a winch ; when frozen they snap only
too readily. It was always necessary to “walk away” with them when hauled, and let
them lie out straight on the floe. If, however, the depth was greater than 30 fathoms,
or thereabouts, they lay out in festoons. Lengths of flexible steel rope not exceeding
an eighth of an inch in diameter are strongly recommended, as these can be wound on
a small light winch, but it is necessary to be on the sharp look-out for kinks, which are
of far greater importance than in temperate climates. The use of steel rope involves the
use of snatch-blocks and tripods. A single winch secured to a sledge is sufficient for
any number of holes, also a single snatch-block. The tripod should be frozen in over
each hole, the rest is a mere matter of management. Another very important tool of
which we were quite deficient is an ice saw, some 3 or 4 feet long, with a wooden
handle, to be worked by one man. For keeping the holes open and for negotiating
eracks these would be invaluable. Our smallest ice saw was 13 feet long, and
useless for biological purposes without a number of men.

‘

The lines were very frequently “ stranded,” though never cut through, presumably
by the seals coming in contact with them and snapping at them as they passed ; there
did not appear to be any other reason for this. The lines had then to be cut through
and knotted. Although the line was always hauled over a bar, usually the pricker,
it was—especially in the deeper water—deflected by the current and, cutting into the
ice, hitched up at every one of the knots, which before long were numerous. This
rendered hauling the traps single-handed rather a difficult matter, but the lines stood
the strain well; it was only when completely frozen that they snapped. ‘The traps
used were at first wooden frames two feet square at the base, covered with mosquito
netting, after the fashion of a lobster-pot. As the ice increased in thickness these
rigid traps became difficult to negotiate through the holes, and moreover supplies were
not inexhaustible. The ordinary tow-net, tied up at one end and baited, was much
more convenient and quite as effective. Swabs attached to the traps were always
used and very satisfactory.

Dredging in some form was always carried on inside the 25-fathom line, but
beyond this depth stationary traps only could be used. However, in deep water
(125 fathoms) the trap or D-net was frequently sent down light and very slowly, so
as to be carried by the current as much as possible from the vertical. Then one or
two 25-lb. sinkers were sent down and the net hauled. Sometimes this was very
successful, sometimes it was not. The captures were brought to the ship either in
glass bottles or in a large tin-lined packing-case previously made water-tight. In the
winter of course everything froze at once and had to be thawed out on board ship.
In the summer the specimens were hardly so well off, for, although they did not freeze,

VOL, III. Cc

10 T. V. HODGSON.

the water was generally full of ice crystals which, with the jolting of the sledge as
it travelled shipwards, cut the more delicate specimens to pieces.

If the flora of McMurdo Sound was poor, the fauna was extremely rich, as the
collections described in this and other volumes show. It is to be regretted that the
difficulties of the investigation precluded the capture of specimens from greater depths
and distances from the ship, so that a more complete comparison of the fauna at
different zones could be made.

APPENDIX.

Two other matters require attention by those who visit the distant south. One concerns the trawls
and nets generally. On the outward voyage of the ‘ Discovery’ it was found extremely difficult, if not
impossible, to keep the nets dry owing to constant leakage into the deck-houses. As this bade fair to
continue throughout the voyage, as it actually did, all the nets were tarred in New Zealand as an attempt
to preserve them; it was successful in this respect, but it depreciated their value for work in cold
temperatures. They became so hard as to be difficult to manipulate, and also inflicted far more injury on
the specimens than they would have done if treated in another way. A thorough soaking in oil is
suggested.

The other matter concerns the work at sea ; as a matter of fact very little was done. An accumulator
of some form is almost a necessity, certainly if any extensive work is contemplated. The one provided was
the old pattern of india-rubber bands as supplied to H.M.S. ‘Challenger.’ The instrument was quite
useless. The cold weather rendered the rubber bands hard and brittle ; apart from that, the days of the
hemp rope are over, and the great weight of steel ropes renders the use of such an accumulator a very
cumbrous affair. The only kind that can be used in a Polar climate is one made of steel springs, such
as that used by H.S.H. the Prince of Monaco, or by the Norwegian Government on board the
‘ Michael Sars.’

MGR Wisc 2.

Valen @ik © DA.
By Sm C. Enior, K.C.M.G., LL.D.
(2 Plates.)

Tue Pteropods collected by the ‘ Discovery ’ comprise the following species : —

l
Name. Quantity. Locality.

1. Limacina antarctica, Woodward. Numerous | Winter Quarters, and the region about
Lat. 61°, Long. 140° E.

5

2. Limacina retroversa* (Fleming) . | Moderately abundant | From Long. 95° 43’ W. to Long. 175° 33’
| ., and from Lat. 55° to Lat. 61° S.
| None from Winter Quarters.

3. Clio sulcata (Pfeffer) . : . | Two specimens and | Lat. 63° 04’ 8., Long. 175° 43'S.
| some fragments

4, Clione antarctica, EK. A. Smith | Numerous Winter Quarters.

5. Spongiobranchaea australis, D’Orb.. Five specimens Winter Quarters, and Lat. 55° 31’ &.,

Long. 156° 19' E.

Winter Quarters were in Lat. 77° 49’ S., Long. 167° 7’ 4” E.
* Some naturalists might regard the forms here called Limacina retroversa as at least two distinct species.

Though ZL. antarctica and Cl. antaretica are represented by numerous specimens,
and clearly are enormously more abundant than the other species, the quantities
contained in each tube suggest that they do not occur in such great shoals as the
northern forms.

I received the specimens in two consignments, described respectively as Pteropods
and Pteropods from the Plankton. The former, it would seem, were taken out of
holes cut in the ice ; the latter in the open sea. In most of the tubes the Pteropods
are mixed up with other forms, such as small crustaceans, larvee of Lamellariide, and
a globular gelatinous molluse (probably Lamellaria mollis, E. A. Smith). In the
majority of specimens the soft parts are well preserved, but the fragile shells are not
only broken, but partly dissolved by the fluid in which the animal has been killed
or kept. The number of perfect shells in the collection is small.

In the above table I have entered Limacina antarctica and Clione antarctica as

Cc 2

2 = SIR C. ELIOT.

distinct species, and not as varieties of L. helicina and of Clione limacina; but I
have entered as ZL. retroversa specimens which others might be disposed to call
L. australis or L. lesueuri. 1 have given below my reasons for these identifications
and distinctions, but I recognise the possibility of interpreting the facts differently
and also the uncertainty of some of the facts. An examination of several
collections shows that both the shells and soft parts of Pteropods are very
susceptible to the influence of the fluid in which they are preserved, so that
individuals belonging to the same species may become superficially dissimilar in
shape and colour. To this must be added the differences arising from age and
local variation. But, making the widest allowance for such influences, I am still
of opinion that the two chief Antaretic forms (L. antaretica and Cl. antarctica) are
distinct from the corresponding northern species.

The distinction is most clearly marked in the genus Clione. Comparing the
Antaretic specimens with typical specimens of Cl. limacina, one may even say that
they are a well-marked species, unless indeed they are immature, as might be
areued from their small size and other features. The differences between Limacina
helicina and L. antarctica are less noticeable, and some may think that the term
variety is sufficient to cover them. But they are internal as well as external, and
it seems to me safer to regard the forms as_ specifically distinct, at least
provisionally. On the other hand, all the Limacinas with elevated spires collected
by the ‘ Discovery, though showing considerable variation, form in my opinion
only one specific type, and if this is admitted, I do not see how that type can be
distinguished from JL. retroversa. The only differences lie in the colour and
striation of the shell. Even if natural, they are hardly of specific value, and they
are very likely due in part to the action of the fluid in which the animals were
kept. The alternative of recognising about four separate species is possible, but
not only do the forms pass into one another by intermediate stages, but they
appear to live together. It is noticeable that Z. retroversa was not found as far
south as L. antarctica and Cl. antarctica, and does not extend much beyond
Lat. 60° 8. This agrees with the distribution recorded by other expeditions.

Whether we call the Antarctic forms varieties or species is, in reality, a comparatively
unimportant question. That there are some differences of detail between them and the
Arctic forms everyone will admit; that the two sets of forms are nearly related is
equally clear. The interesting point is that in both the Arctic and Antarctic seas the
predominant, and as we approach the Poles probably the only Pteropods are closely
allied, or even identical species of Limacina and Clione. The characters which these
Arctic and Antarctic forms present are compatible with any hypothesis which assumes
that they are derived one from the other, or from a common ancestor. Further, the
distribution of these forms is interrupted by a wide zone in which they do not occur.

None of them are recorded from within thirty degrees either north or south of the
Equator,

PTEROPODA. 3

I confess that I have seen no explanation of these facts which appears to me
satisfactory. Our knowledge of the direction in past ages of ocean currents which must
have largely determined the distribution of pelagic forms is slight, and our record of
fossil Pteropods is very imperfect. As far as I can ascertain, none are recorded from
South America or South Africa, but it hardly seems possible to argue profitably about
the distribution of the group in the past without definite information on this point.

Meanwhile it is interesting to observe that one Antarctic form, Clio sulcata, is
closely allied to a cosmopolitan form, Cl. pyramidata, and may plausibly be considered
as a special adaptation of it to Antarctic life. Also, if Limacina lesueuri is admitted to
be merely a variety of L. retroversa, then L. retroversa is cosmopolitan and bipolar. Is
it not probable then that Clione antarctica and Clione limacina, plus some tropical
forms of the genus, represent variations of a once cosmopolitan species? There
is nothing unnatural in the idea that such a species may have undergone similar but
not identical changes in North and South Polar waters. The species of Clione
inhabiting the warmer seas (Cl. longicaudata, Cl. flavescens, and Cl. punctata) have not
been described in great detail, but they do not seem to differ from the Arctic and
Antarctic species so profoundly as to forbid the supposition that all may be modifica-
tions of one form. It is noticeable that the Arctic and Antarctic species have
invariably three pairs of buceal cones, whereas the warm water species have two pairs
or only one. The forms of Limacina which predominate in the tropics are not nearly
allied to ZL. antaretica and L. helicina, but Dr. Meisenheimer states that L. rangi
“ weist ausserordentlich nahe Beziehungen zu L. helicina auf,” * although he separates
the two. This species, as to whose independence authors are not agreed, has been
found as far north as Lat. 33 8. LZ. helicoides, which is known only by the shell,
resembles L. helicina and L. antarctica in having a flat spire, though it is specifically
distinguishable. It is widely, though sparsely, distributed in the warmer waters of the
Atlantic.

The anatomy of the Pteropods has been so fully described by various authors that
in the following notes I have not touched on it, except when necessary for purposes of
classification. My best thanks are due to Mr. T. J. Evans, Lecturer on Zoology in the
University of Sheffield, for preparing sections and drawings, and for much assistance.

LIMACINA.

Ten or eleven species have been referred to this genus, but the animals of
L. triacantha and L. helicoides are unknown, and opinions differ as to whether all
the other species are really valid. The relationships of L. helicina and L. antarctica,
as well as of ZL. retroversa, L. lesueuri and L. australis are discussed below.

There is some difference of statement as to the presence or absence in this
genus of organs called jaws, and possibly some variation in the texture of the

* Siidpolar, Expedition. Pteropoden, p. 105, 1906.

4 SIR C. ELIOT.

organs themselves. Sars, who is quoted by some subsequent authorities, gives
(Mollusca Regionis Arcticee Norwegiz, 1878, p. 328) mazvillae nullae as a character
of Fam. Limacinidae, but on Plate XVI., 17, b, he figures a collection of lamellae with
denticulate or fringed edges, and explains them (p. 462) as mazilla una 190" aucta.
But in fig. 21, b, of the same Plate, representing the buccal parts of Clione limacina,
what appears to be one of the hook sacks is described as maxilla una 15" aucta.
It is clear therefore that he did not restrict the meaning of the term maxilla to the
ordinary molluscan jaw.

Neither in Limacina antarctica nor in L. retroversa have I been able to isolate
any hard jaws, such as are frequently found in Opisthobranchiata, but sections show
that the sides of the cavity bear folds which are covered with a very thin chitinous
layer.

LIMACINA ANTARCTICA, Woodward.

See Pelseneer, ‘Challenger’ Reports, Vol. XXIII. (1888), Thecosmata, p. 22; 7d., Voyage du S. Y.
Belgica, Mollusques (1903), p. 29 ; Meisenheimer, ‘ Valdivia,’ Pteropoden (1905), pp. 7, 8; id., Die
Arktischen Pteropoden (1906), pp. 409-413 ; zd., Stidpolar Expedition, Pteropoden (1906), pp. 96-98.*

The numerous specimens obtained by the Expedition differ considerably in size,
colour, and general appearance, and may be classified under three heads :—

(A.) Black and yellow specimens. The majority are about 3 mm. wide and
2mm. or a little less in height, but four are as much as 5°5 mm. broad and rather
more than half as much in height. An operculum was often found. The fins,
hermaphrodite gland, and the majority of the organs are of a pale lemon yellow,
varying considerably in intensity, but contrasting markedly with the black mass
composed of the digestive organs, and especially of the liver. The shell is extremely
fragile and in bad condition, being not only considerably broken in nearly all
specimens, but also pierced by numerous holes. The word picric is written on some
of the labels, and probably all these specimens were killed with picric acid. This
has caused the fins and head parts to remain well expanded, but the action of the
acid has coloured the light portions yellow and partially destroyed the shells.

Specimens of this class are recorded from :—

ie aod ar am
Cy Dats: t 5 . Numerous.

Long. 140° 12' E.
(2) Lat. 61° 40'S. i

Long. 141° 32' E.
(8) McMurdo Bay . : ° > g %

. Fairly numerous.

(4) Lat. 66° 52'S. i Af
Long. 178° 15’ E. $ © a

Gy wo: - : ‘ : *

(6) Wood’s Bay. : : 6 og

* Full titles and references will be found at the end of the Memoir.

PTEROPODA. 3

(B.) Whitish specimens. In these the prevalent coloration is white or grey,
the black visceral mass being seen more or less distinctly, according to the
transparency of the shell. The animals are not much expanded, the fins being
usually retracted, but the shells are better preserved than in the black and yellow
specimens, being thicker, more opaque, less broken and less perforated. The breadth
is about 3 mm. and the height about 1°75. These specimens were probably put
straight into alcohol, which accounts for the contracted state of the soft parts and
good preservation of the shell. They are recorded from :—

CO AWELOEE s. 2 : : . Fairly numerous.
(2) McMurdo Bay . : : . A few.

(C.) These specimens, which are extremely numerous, are distinguished by
(a) their small size, the diameter being usually about 1°50 mm., and few whorls ;
and (b) the position of the fins, which form a sort of hood extending beyond the
anterior part of the body. As this hood often bears fragments of shell, the whole
animal sometimes bears a resemblance to Limacina inflata, as figured by Souleyet.
But a comparison with specimens of that form, kindly lent me by Mr. E. A. Smith, 1s.0o.,
shows that the resemblance is merely superficial, and that there is no true rostrum
above the hood. The coloration is varying: pure yellow, black and yellow, white,
erey, and dark grey being all found. Some of the animals have been treated with
picric acid, and some apparently put straight into alcohol or formol. The majority
of the shells are poorly preserved, though in so large a mass of material good
specimens were not wanting. An operculum is generally present; otherwise this
form resembles those described above as A and B, and may be regarded as a
younger stage.

The Expedition brought back twenty-three tubes containing specimens of this
type, all captured at Winter Quarters, none being recorded from elsewhere.

Taking all the specimens together, I have little doubt that they represent a
single species which may be thus described.

The shell is between 5 and 6 mm. broad in large individuals, but considerably
smaller in the majority, and the height is about half the breadth or rather less. In
the best specimens it is white, imperfectly transparent, and faintly but distinctly
striated, but the action of the preserving fluid often renders it extremely fragile
and the striation may disappear. There are 3-6 whorls (5-6 in large specimens)
divided by distinct sutures. The last whorl is considerably dilated and terminates
in a large rounded lip, which is generally broken. The spire is somewhat flattened.
The umbilicus is moderately wide and deep, but is not surrounded by any raised keel
or special border.

In large specimens the fins (fig. 1b) are about 4 mm. long and 3 mm. broad
across the tips. They are shaped much as in Z. helicina and bear a small accessory
lobe. The right tentacle is well developed, the left rudimentary. The foot is ample

6 SIR C. ELIOT.

and the posterior lobe is rather deeply divided. An operculum is often present in
specimens of both small and moderate size, certainly in several which have a
diameter of at least 3 mm., but is absent in the largest and is probably caducous in
adult life. It is much as figured by Pelseneer (‘ Belgica,’ figs. 70, 71) and has a
short sinistral spire of two whorls (fig. 2). The balancer or long narrow lobe on the
right side of the mantle is well developed.

The jaws mentioned by some writers could not be found by ordinary dissection,
but in transverse sections there were seen in the part of the buccal tube lying in
front of the radula, dark pigmented folds covered by a very thin layer of a lighter
colour and apparently chitinous. In the floor of the cavity are two ciliated grooves
(fig. 3).

In individuals having a diameter of 3 mm. or more the radula consists of
8-11 rows containing three teeth each. The teeth (fig. 4) present slight but distinct
and persistent differences from those of L. helicina (fig. 5) and are larger in
proportion to the size of the animal. In the median teeth (4a) the hair-like
denticulation is longer and extends higher up the sides of the median cusp, which
consequently appears to be shorter; the base is straighter and bears at either end
two or more lobes and bulges. The laterals (4b) are less curved than in L. helicina
and the denticulation, as in the median cusp, extends higher. In the oldest row of
teeth the laterals are very thin (4c) and the base of the median tooth is simpler,
without bulges.

The whole interior of the stomach (fig. 6) is led with a thin layer of chitin which
gives rise to five stomach plates and also to various prominences and spines (6a)
which are larger in the cardiac portion, but do not form four definite accessory
plates, such as some authors have reported in FL. helicina. The four large stomach
plates (fig. 6a) consist of a rectangular or oval base out of which rise one or more
prominences with strongly jagged edges. These plates appear to play on one another,
which probably modifies the details of the shape in each case: in two the point of
the projection is more acute and more bent than in the others. When the four pro-
jections are in contact a conical hollow remains between them posteriorly and into
this fit the prominences of the fifth plate (fig. 6a, e), which is smaller than the
others and lies below them on the pyloric wall of the stomach, but is of essentially
the same form, though generally seen sideways and hence apparently more triangular.
In all the specimens examined the stomach was found to contain globigerina and
diatoms.

The inner whorls of the shell are entirely filled with the white hermaphrodite
oland.

Authorities are not agreed whether this form is a separate species (Pelseneer)
or a variety of L. helicina (Meisenheimer). In the hope of contributing to a
decision, I have compared with the ‘Discovery’ collection a large number of
specimens kindly furnished me by Professor D’Arcy Thompson, C.B. (from Davis

PTEROPODA. 7

Straits and North Pacific), the British Museum and others. The following table
will show the points of difference which I have found to be constant :—

LIMACINA ANTARCTICA. LIMACINA HELICINA.
1. Maximum breadth observed 5°5 mill.; fins 1. Considerably larger. Maximum breadth observed
about 4 mill. long. 9 mill. ; fins 10 mill. long.
2. Shell with very fine transverse striation or with 2. Striation much stronger and more distinct :
none at all. (But see what is said above as sometimes darker than rest of shell.

to the injuries sustained by the shells.)

is)

3. Umbilicus without any sort of keel or distinct . Umbilicus surrounded by a very distinct circular
border, even in the largest specimens. raised border, which is invariably present in
well-preserved specimens of moderate size.

4, The colour of the animal is light, with the 4, The upper and inner whorls are marked with a

exception of a distinct dark mass composed dark stripe following the direction of the
of the viscera and situated chiefly in the spiral, so that the shell when seen from above
second half of the first whorl. The inner presents an alternation of dark and light
and upper whorls are entirely light (fig. 1b). spiral stripes. The dark stripe is not hepatic,

but is formed by a pigmented membrane
which appears to be continuous with the
mantle (fig. 14).

5. The posterior lobe of the foot is more deeply 5.
and distinctly divided than in L. helicina.

6. The hair-like denticulation of the teeth extends 6. The denticulation is less developed and the cusp

to a considerable height, so that the main consequently seems more prominent. The
cusp is less conspicuous. The base of the base of the central tooth is hollowed out
central tooth is fairly straight, with knobs at almost into a horseshoe shape.

the end.

Other points, such as the shape of the operculum mentioned by Prof. Pelseneer,
seem to me less certain. Whether the differences tabulated above are sutlicient specific
characteristics must depend on each naturalist’s view of what constitutes a species,
there being no accepted definition of specific difference. But as far as the collections
which I have examined are concerned, these differences are persistent and concomitant,
and it seems to me that when so decided a character as the presence or absence of the
raised border round the umbilicus is accompanied by differences in size, colour and the
teeth of the radula, the two forms are entitled to specific rank, though the divergences
by no means show that they have originated independently, but rather support the
idea that they are differentiations of a common ancestor or one of the other.

VOL. III. D

fore)

SIR C. ELIOT.

LIMACINA RETROVERSA, Fleming.

See especially Meisenheimer on Limacina retroversa, Siidpolar Expedition (1906), IX. Band, Zool. I. Band,
Heft II., pp. 103-105 ; Eydoux and Souleyet on Spirialis australis, Revue Zool. (1840), p. 237, and

5

Bonite (1852), p. 222; Pelseneer, ‘Challenger’ Report, LXV., pp. 25-27; Munthe, Pteropoder,
pp. 8, 9 (1887).

There are six tubes containing specimens of a whitish Limacina of small or
moderate size, with a spire of somewhat varying height, but never so low as that of
L. helicina or L. antarctica. The labels are :—

Lat. 55° 44'S. Long. 95° 43’ 30” W. 5 fathoms (11 spec.).

2. Lat. 56° 12'45"” 8S. Long. 136° 18’ 30” W. 10 fathoms (3 spec.).
8. Lat. 57° 25'S. Long. 151° 2’ E. (Several spec.)

4, Lat. 59° 19’8. Long. 120° 24’ 30” W. 5 ms. (6 spec.).

5. Lat. 59° 34'S. Long. 106° 28’ 13” W. 5 fathoms (4 spec.).

6. Lat. 61° 13’ 30" 8. Long. 173° 33’ E. (Several spec.)

The tubes contain comparatively few specimens, and suggest that this species is
not found in abundant shoals.

The shells show considerable variation in form (fig. 7). No differences were
found in the animals, though, as they were without exception retracted into
their shells, the investigation of the foot and fins was difficult. An accessory lobe
was, however, found on all the fins which could be extended, and after examining
numerous specimens of ZL. retroversa from the coast of Scotland, I can confirm
Meisenheimer’s statement (Siidpolar Exped., p. 104) that the lobe occurs in this
northern form. The radula appears to be much the same in all specimens, and
substantially as in L. retroversa.

The shell varies in colour from greyish white to yellowish brown, but is always
rather opaque, not striated, but covered with fine granulations arranged in no apparent
order. The height of the spire varies from 1 mill. to 2 mill., the latter dimensions
being rare, and the maximum breadth across the last whorl is 1 mill. The umbilicus
does not vary materially in shape; it is distinct, straight, rather narrow, and
I did not find the distinction in breadth mentioned by Prof. Pelseneer (‘ Challenger’
Reports LXV., pp. 26 and 27). The mouth is subquadrangular.

The variation in the shape of the shell produces two types. Type A (fig. 74)
is tall, with very deep sutures and six or seven whorls, which increase symmetrically
in size, the last not being disproportionately large. In many of these shells, as
preserved, the columella is not continued at the side of the mouth. Type B (fig. 7c)
is smaller and lower; the sutures are not so deep; there are only four or five whorls,
and the last whorl is disproportionately large and swollen,

PTEROPODA. 9

If these forms were sharply distinguished from one another, they might be
regarded as separate species, but in a few cases intermediate variations (fig. 7B) occur,
such as a tall shell with deep sutures and seven whorls, of which the last is
disproportionately larger than the others. Moreover, all the variations may be
found in the same tube, which seems to show that they live together in their natural
state. I think that the low form in ZL, lesweurt, and some varieties of the high form,
seem to be typical examples of Z. australis. But if these forms pass into one another,
and are not specifically distinguishable, they are not, in my opinion, specifically
distinguishable from L. retroversa. Dr. Meisenheimer (Siidpolar Exped., p. 103) has
already identified Z. australis with this northern form.

I have compared the contents of these six tubes with very numerous specimens
of Z. retroversa captured in the North Sea (where it seems to occur in vast quantities)
and kindly lent me for examination by Prof. D’Arcy Thompson, C.B. The only points
in which the whole series of Antarctic specimens can be said to differ from the northern
specimens are the colour and surface of the shell. In the Antarctic forms it is
opaque, not striated, and covered with a fine, irregular granulation ; in the northern
form it is hyaline, transparent, and finely striated, the striae being composed of
dots arranged in fairly regular, but not perfectly continuous, lines. These differences
do not appear to me to have specific value. I can find no distinction in the breadth
of the umbilicus or the obtuseness of the spire. Though L. retroversa is commonly
said to have an acute spire, many of my specimens are quite as blunt at the tip as
L. australis,

Meisenheimer (Siidpolar Exped. p. 106) regards ZL. rangi and L. lesueuri
as separate species. I confess I doubt whether this distinction will be found to
hold good, but the specimens now under consideration are certainly not L. rangi
as defined by him, for the spire is higher, an accessory lobe is present on the fin,
and the umbilicus is not particularly broad.

Cio suLcaTa, Pfeffer.

Pfeffer, Uebersicht der auf S. M. Schiff Gazelle gesammelten Pterpoden, Monatsb. k. preuss. Akad. Wiss.,
Berlin 1879, p. 240.

Pelseneer, ‘ Challenger’ Reports, No. LXY., Thecosomata, p. 62.

Two specimens labelled “1. 1. 702. 63° 04' S., 175° 48’ E.”, of nearly the
same size and measuring about 18°5 mm. in length and 11°5 mm. in breadth.
The shells are very fragile and both are broken, but they must have been about
14°5 mm. long and 8 mm. broad at the top. When the animal is inside they are
coloured rosy red by the viscera, but when empty are of a bluish white. The
sides are inclined towards one another, and are not parallel in any part. There are
lateral keels on the anterior portion of the shell, but they disappear before the

D2

10 SIR C. ELIOT.

end. The shape of the lips is doubtful, owing to the injuries that they have
sustained. The anterior portion of the hack seems to have been triangular. The
ventral surface is not re-entrant, but flattish and only slightly convex. The
dorsal surface is moderately convex. The anterior part is broken, but appears to
have borne a median ridge and four lateral ridges, which disappear in the posterior
half. The whole surface of the shell bears numerous fine transverse ridges. After
the termination of the animal inside, the shell is produced into a thin point
4 mm. long. The embryonic shell resembles Pelseneer’s figure (/. ¢., pl. IL, 9) of
Clio sulcata rather than Clio australis,

The foot, wings and other portions of the animal protruded from the shell are
yellow, the viscera reddish. The wings are ample, about 6 mm. long and 5 mm.
wide, deeply bi-lobed and with wavy edges.

The interior of the liver is deep red. The stomach contains four large plates,
bearing a conspicuous Y-shaped ridge on the outside. There also appears to be a
fifth plate, smaller, indistinct and triangular, as well as a double row of minute
plates. The radula is tri-seriate. The sides of the teeth are somewhat irregular
and indented, but not serrulated.

I think that these specimens belong to the Clio sulcata of Pelseneer, 1. ¢., but
feel some doubt whether that species is really identical with Pfeffer’s Cleodora
suleata.

To the same species are probably referable a small Clio, to which fragments
of shell are attached and two posterior ends of shells, one of which bears
remarkably large and distinct transverse furrows. They are all labelled
Qe 12-201, S4o01F Ss. 17.07 49! eH:

CLIONE ANTARCTICA, E. A. Smith.
See E. A. Smith, Coll. ‘Sonthern Cross’ Mollusca (1902), p. 210, and pl. xxv., figs. 7, 8. See also

Meisenheimer on Clione limacina, var. antarctica, in Stidpolar Expedition, Pteropoden (1906),

pp. 101-103.

The labels state that the numerous specimens representing this form were all
captured at Winter Quarters in from three to ten fathoms, the great majority at
the latter depth. They fall into two classes, chiefly distinguished by their colour,
some being yellowish and generally well expanded; others, brownish or greenish
grey, and much more contracted. These differences seem due to the method of
preservation rather than to natural variations, and the labels make it probable that
the yellowish specimens were killed with picric acid.

The measurements of a large specimen are: length, 17 mm., breadth of the
body at its thickest part, 6 mm., breadth across the fins, 9 mm. The colour is
usually a pale lemon yellow (probably representing an original white), sprinkled
with round dots of opaque yellow. The number of dots varies greatly, but they
are entirely absent in comparatively few individuals. They are much more

PTEROPODA. 11

conspicuous in the yellow than in the grey specimens. In their natural condition
the integuments seem to be semi-transparent, especially above the foot, where the
buccal muscles are often clearly visible. Below the foot they are more opaque,
but the blackish viscera can be somewhat indistinctly discerned. The shape is
moderately stout and moderately elongate, either tapering fairly symmetrically to
the terminal knob, or prolonged into a distinct tail. The majority of the specimens
have preserved the three larval rings, and when they are absent it seems probable
that they have been obliterated. The first ring is represented by a circular band
a little below the mouth, bearing 14-18 whitish prominences set at regular
intervals. Some distance below the fins and about the middle of the body is the
second ring, a very distinct line often accompanied by a deep constriction At the
end of the body is found, with a few exceptions, another deep constriction dividing
the tip from the rest, so that the animal terminates in a knob, which, in well-
preserved specimens, is surmounted by a circular frill.

The fins are of moderate size, transparent, and show inside a network of muscles.
They are of somewhat varying but rounded outline, and are never triangular or
quadrilateral. In many cases the base is much narrower than the rest, and this
feature is probably natural.

The two anterior lobes of the foot are fairly ample and inclined so as to form
an acute angle. They are attached to the body only by a narrow base, the greater
part of the flap being entirely free. The posterior lobe is an acute-angled triangle,
rather long and thin, but proportionately to the size of the animal larger and stouter
than in Clione limacina.

In specimens in which the buccal parts are fully everted there may be seen two
pairs of tentacles, three pairs of buccal cones, and a pair of hooksacks. The anterior
tentacles are distinct and fairly large. The posterior tentacles are small, and in most
specimens can only be found by following the nerves, having become invisible owing
to retraction. The buccal cones are soft in the best preserved specimens, but very
distinct. The middle one on either side is the largest. The two which are nearest
to the foot are set close together, but are separated from the dorsal cone by a
somewhat larger interval (fig. 11a). The hook sacks, which are not unfrequently
everted in the form of two bundles, contain 60-70 yellowish hooks, slightly curved and
somewhat hollowed out on the inner side. They are set in several rows, those at the
end being smaller than the rest and forming a bundle.

There are no jaws. The radula (fig. 10) consists of about thirty rows, which have
a maximum formula of 8. 1. 8, but the median tooth is very small, and is only found
in one or two of the hindmost rows. Except in this posterior portion, the radula is
split into two halves, which extend over two protuberances towards the right and
left, so that the whole organ has somewhat the shape of the letter Y, and in the
greater part of its length offers no place for a median tooth. ‘This disposition
was constant in all the radule examined, and seems to be natural and not due to

12 SIR C. ELIOT.

distortion. The following is an analysis of a radula of 32 rows, row No. 1. being
the hindmost :—

Rows 1-11 8 1 8, the median tooth being smaller ini than in i.
Rows iii-ix . 8 0 8.

Rowx . . 7x 0x7, where r indicates a rudimentary lateral."
Rows xi—xiv [PVN

Row xx . - 6r 0x76 3 : + "

Rows xxi-xxvi. 6 0 6.

Rows xxvi-xxx 5 09.

Row xxx 3 a4t 20) 4:

Row xxxil 3 0 3.

The shape of the teeth is much as in Clione limacina, except that the median teeth
(11gh) are markedly smaller and less distinctly cuspid, and that the laterals in the
hindmost rows (1lef) have forked bases. It is noticeable that several specimens have
been preserved in the act of holding and apparently eating small elongate fishes,
which are still attached to them (fig. 12).

In Cl. limacina the penis is large, frequently found exserted, and provided with
a large accessory organ (vide Boas’s figure reproduced by Meisenheimer in Die
Arktischen Pteropoden, p- 415); but these characters are not found in any of the
present specimens of Cl. antarctica. The penis is small, invariably retracted, and no
accessory organs were discovered. Too much stress should not be laid on this
difference, for no doubt the accessory organs may have a very different appearance
in the same species when exserted and when retracted.

The presence of the larval rings and the small size of the penis naturally suggest
that this form is immature, and it is also noticeable that the specimens were all captured
between the months of November and March (though in different years), most of them
in January and February. This certainly makes it probable that they are all in the
same and possibly not adult stage of development. On the other hand, it is clear from
a comparison of Arctic and Antarctic specimens of the same size that the young Clione
limacina is not more like Cl. antarctica than are the full-grown individuals. Also
the type specimens of Clione antarctica, captured by the ‘Southern Cross’ off
Cape Adare and lent to me for examination by the kindness of Mr. E. A. Smith, 1s.0.,
resemble those found by the ‘Discovery’ in most external points except the
colour, which is dirty green with purplish spots, a difference no doubt due to
the method of preservation. The length is 20 mm. or a little less, the larval rings
are more or less distinctly visible, the fins, foot, and buccal cones are as in my
specimens.

} The conformation of the radula may be due to one or both of two causes :—(a) In most opisthobranchs
the front, that is the earliest rows of the radula, contain fewer teeth than the posterior or later rows. (6) As, in

this case, the radula is split into two portions, it is possible that not only the central tooth, but the inner laterals
on either side are worn away, in which case r would indicate a vestigial tooth.

PTEROPODA. 13

These specimens found by the ‘ Discovery’ seem referable to Cl. antarctica, E. A.
Smith (/.c.). They can hardly be identified with Cl. longicaudata, Cl. flavescens or
Cl. punctata, because those species, though imperfectly known, are said to have only one
or two, and not three pairs of buccal cones. In my opinion they are also specifically
distinguishable trom Clione limacina, though the species are, no doubt, nearly allied.
The superficial difference in appearance is striking, and the divergent characters of the
two species may be tabulated as follows :—

CLIONE ANTARCTICA. CLIONE LIMACINA.

1. The part of the body behind the fins is shorter 1. A specimen 18 mm. long consists of 2°5 mm.

than in the Arctic form. A specimen 18 mm.
long consists of 6 mm. head and fins +
12 mm. body.

There is a distinct neck behind the fins.

. Considerably smaller than the Arctic form. Few
individuals exceed 20 mm., even when arti-
ficially extended. E. A. Smith gives 22 mm.
as the length ; presumably the maximum of
his specimens.

. The integuments are thicker, firmer, and less
transparent than in the Arctic form. In
most specimens they are plentifully be-
sprinkled with opaque yellow spots, some-
times a little raised.

doubtful, though not disproved.

. The visceral mass extends backwards almost
into the posterior third of the body.

head and fins + 15°5 body.

The broadest part of the body is just behind
the fins, and as far as there is a neck it is
between or above the fins.

. Specimens 40-45 mm. in length are frequent.

. The integuments are thin and _ transparent.

Though spots are present they are not con-
spicuous, and as a rule can only be seen when
carefully sought for. The whole animal is
flabby, and almost gelatinous.

. Three, or at least two, larval rings are habitually 4. No larval rings found in individuals measuring
present in individuals measuring 15 mm. or as much as 10 mm. When traces of the
more in length. posterior ring are found in small specimens it

is not shaped as in Clione antarctica.

. The base of attachment for the anterior lobes 5. The base of attachment for the anterior lobes is
of the foot is a narrow band. The posterior broad.
lobe is larger and stouter in proportion to the
anterior lobes than it is in Clione limacina.

. There is an interval between the dorsal cone 6. The cones are equidistant. The dorsal is the
and the other two. The median cone is the largest and the ventral smallest.
largest.

. Median tooth very small, and present only in 7. Median tooth larger, and present in all or most
hindmost rows of radula. Laterals in hind- rows. Laterals with forked bases not found.
most rows have forked bases. The number The number of laterals does not increase so
of laterals gradually increases from 3 to 8, markedly, and the rudimentary teeth are
the innermost teeth of the half row being found at the outer ends of the rows.
sometimes rudimentary.

. Penis small, and presence of accessory organ 8. Penis proportionately much larger, and provided

with a large accessory organ.

. The visceral mass is more compact and rounded,

extending only a little way behind the fins.

14 SIR C. ELIOT

SPONGIOBRANCHAEA AUSTRALIS, D’Orb.

See especially Pelseneer, ‘Challenger’ Report LVIII., pp. 18-20 ; Meisenheimer, ‘ Valdivia,’ pp. 47-49 ;
id., Siidpolar Exped., pp. 99-101.

One specimen labelled “ Winter Quarters, 19. 11. 08. Mosquito net, 10 fathoms.”
Four others labelled “21. 11.’01. Lat. 55° 31’ S., Long. 156° 19’ KE. ; 15 fathoms.”
These localities support the idea that the species is circumpolar.

A large elongated specimen is about 30 mm. long and 8 mm. broad, another of
about the same volume is contracted and stouter, measuring 22 mm. in length and 11
in breadth. The colour of the body is violet, grey or brown, with ill-defined bands of
lighter colour round the median constriction and the posterior gill. The buccal parts
and the appendages which bear the suckers are yellowish white, and contrast strongly
with the body colour. The foot is bluish with yellow edges, the fins yellowish.

The lateral gill is hardly visible in any of the specimens. It is at most an
inconspicuous bladder-like projection which interrupts the median constriction, and is
lighter than the surrounding parts. The posterior gill is distinct and well-developed.
The median lobe of the foot is long and tapering, the side lobes are small, and the space
between them bears a few deep furrows. The parts behind the head, including the fins,
are much contracted, but in the only specimen where the fins can be seen they appear
to be about 6 mm. long, and broader, and more deeply lobed than previous authors
have described.

The buccal parts are everted in one specimen. The large proboscis bears a papilla
as described by Pelseneer, and at its base are two large and distinct tentacular flaps.
Each of the acetabuliferous appendages bears 8 stalked suckers, which increase in size
upwards. The two lowest are very small; the upper ones are about 1 mm. wide. Just
before the radula is the jaw, which appears to be a collection of small straight spines or
teeth. At the sides of the radula are two small short hook-sacks, filled with hooks of
various shapes. The formula of the radula is about 26 x 8. 1. 8, and the teeth are as
in Pelseneer’s plates. The median tooth is tricuspid. The laterals are longish, slender,
and curved at the tips. The first lateral bears a denticle on the inner side of the base
which is not found in the others.

Winter Quarters appears to be the furthest southern record of Sp. australis, which
is probably circumpolar, since it is now recorded from Long. 60° W., and Long. 5° E.
to Long. 30° E, Long. 54° E. and Long. 167° E. It is recorded from as far north as
Lat. 35° §.

PTEROPODA. 15

MEMOIRS REFERRED TO ABOVE.

1. Boas.—Spolia atlantica, Videnk. Selsk. Skr., Gte Raekke, naturvid. og math. Afd. 4, Bd. 1,
Kjébenhavn, 1886.

2, Eypoux er SouLeyer.—Description sommaire de plusieurs Ptéropodes nouveaux ou imparfaitement
connus. Revue Zoologique, 1840.

3. Imp. Voyage autour du monde, exécuté pendant les années 1836 et 1837 sur la corvette ‘ Bonite.’
Zoologie, tome II. Paris, 1852.

4. MEISENHEIMER. Pteropoda: in the Wissenschaftliche Ergebnisse der Deutschen Tiefsee Expedition
auf dem Dampfer Valdivia, 1898-1899. Jena, 1905.

5. Ip. Die arktischen Pteropoden : in Fauna Arctica. Jena, 1906.

6. Ip. Die Pteropoden: in Deutsche Siid-Polar Expedition, 1901-1903. ix. Band, Zoologie i. Band.
Heft ii. Berlin, 1906.

7. Ip. Die tiergeographischen Regionen des Pelagials, auf Grund der Verbreitung der Pteropoden.
Zoolog. Anzeiger xxix. (1905), pp. 155-163.

8. Munrun.—Pteropoder i Upsala Universitets Zoologiska Museum. Bihang till K. Svenska Vet. Akad.
Handlingar, Band 13, Afd. iv. no. 2. Stockholm, 1887.

9, PELSENEER.—Challenger Reports, vol. xix., 1887. Gymnosomata.

10. Ip. op. cit., vol. xxiii., 1888. Thecosomata.

11. Ip. op. cit., vol. xxiii., 1888. Anatomy.

12, Ip. Mollusques: in Résultats du Voyage du 8. Y. Belgica. Anvers, 1903.

13. G. Prerrer.—Uebersicht der wiithrend der Reise um die Erde in den Jahren, 1874-1876 auf S. M.
Schiff Gazelle und von Herr Dr. Jagor auf seiner Reise nach den Philippinen in den Jahren 1857-
1861 gesammelten Pteropoden. Monatsbericht der K. Akademie der Wiss. zu Berlin 1879.
pp. 280-247.

14. G. O. Sars.—Bidrag til kundskaben om Norges Arktiske Fauna. I. Mollusca regionis Articae
Norvegiae. Christiania, 1878.

DESCRIPTION OF FIGURES IN PLATES I. AND IL.

1. Distribution of colour in animal of Limacina helicina (a) and L. antarctica (b), the shell being removed.

2. Limacina antarctica : operculum.

3. Transverse section through buccal cavity of Limacina antarctica : (aa) folds covered with thin chitinous
layer ; (0) radula ; (¢) ciliated groove.

4. Limacina antarctica: teeth. 4a median ; 4b-e lateral teeth.

5. Limacina helicina: teeth. 5a median; 5b lateral teeth.

6. Limacina antarctica : section through stomach. 1-4 stomach plates ; (a) chitinous spines.

6a. Limacina antarctica : stomach plates detached.

7. Limacina retroversa: three varieties.

8. Clione antarctica.

9. Clione antarctica : anterior end of a specimen in which the buccal parts are everted so as to show the
hook sacks. Only two of the three pairs of buccal cones are visible.

10. Clione antarctica: radula.

11. Clione antarctica: separate teeth. (a-d) laterals; (e-f) laterals from the hindmost rows; (gh)
median teeth.

11a. Clione antarctica: side view showing buccal cones.

12. Clione antarctica : specimen captured in the act of eating a small fish.

VOL, Ill. BE

Antarctic (‘ Discovery ’) Exp. PLATE |

Wile J. E. del.] ; [Butterworth se.
Limacina antaretica and L. helicina.

=

Antaretie (‘ Discovery’) Exp. PIA ES Tle

"isd. E. deli]

(Butterworth se.

Clione antarctica.

Cay Wis AAS OuhieA:

PES ANP ERP ODA.
By A. O. Watker, FE.LS.
(13 Plates.)

Tue collection of Amphipoda consists of fifty-three species, of which eighteen are new
to science, belonging to forty-three genera, of which four are new. This may not appeara
very large number considering the length of time the ‘ Discovery’ was in the Antarctic
Seas, yet as (with the exception of the pelagic Hyperiids taken on the voyage) all but some
nine species were collected from holes in the ice at the Winter Quarters, and, therefore, from
a very limited area, it appears to me to reflect great credit on the energy and persever-
ance of Mr. Hodgson under unusual climatic conditions. The long sojourn of the
‘Discovery’ in one spot enables us to observe the seasons at which different species
visit shallow water, generally for the purpose of depositing their ova or young. In the
case of the most abundant species, Orchomenopsis rossi, A. O. W., of which Mr.
Hodgson says that “‘ It was quite the usual thing to take ten to thirty thousand at a
haul,” I only observed one male with fully developed lower antenne and no females with
ova, though some measured as much as 25mm. The young had probably been born
at a considerable depth, and had at once made their way to comparatively shallow
water, the parents remaining in deep water. Again, the almost equally abundant
Eusirus propinquus (G. O. Sars) only exceeded 25mm. in four specimens, three females
with ova or young measuring 48mm., and one male measuring 50mm. ‘This species
resembles in this respect Gammarellus [Amathilla] homari (Fabr.), which I have
observed to visit the north coast of Wales in the early spring, when alone the large
adult females, and more rarely males, measuring nearly lin. in length, can be taken
between tide-marks ; in the summer months every tidal pool swarms with young
specimens.

As in the Arctic Amphipoda, the Lysianassidz greatly preponderate in the number
of genera, species, and individuals. The typical Gammaride, as restricted by Mr.
Stebbing in establishing the families Melphidippide and Lilljeborgidee, are unrepre-
sented. In Professor G. O. Sars’ Amphipoda of Norway there are nine genera with
twenty-one species ; and in Professor Herdman’s Ceylon collection seven genera with
fifteen species.

oOo
oD?

Among the Gammaridz several species are remarkable for their wide distribution :
Ampelisca macrocephala (Lilljeborg) is an abundant Arctic species, though found also in

E 2

2 A. O. WALKER.

temperate seas; Husirus propinqguus (G. O. Sars) and Melphidippa maecrura (G. O.
Sars) have only been recorded before from the more northern waters of Norway ;
Leucothoé spinicarpa (Abildgaard) appears to be ubiquitous, and I am unable to see any
difference between those taken from the ice-holes of the Winter Quarters and those
from our own seas and the tropical seas of Ceylon and the Maldives. This is an
ascidiicolous species, and probably owes its wide distribution to the drifting of its host
by currents and winds. The same may be said of the two spongicolous species,
Polycheria antarctica (Stebbing) and Colomastia pusilla (Grube), of which the former
has also been taken in Ceylon, but not further north ; while the latter has been found in
the British Isles, the Mediterranean, and Ceylon, but is not recorded from Norway or
Arctic seas. These species must have a great capacity of adaptation to extremes of
heat and cold. On the other hand, Orchomenopsis rossi appears to be able to exist
only in water just above the freezing point.*

As species remarkable for peculiarity of structure may be mentioned the following :
Hyperiopsis australis, of anomalous structure, and belonging to a genus so rare that
previous to the capture of the single specimen in this collection only two individuals
of another, but nearly allied species, H. Voeringii G. O. Sars, had been taken off the
coast of Norway ; Thaumatelson herdmani is the only known Amphipod which has its
telson set on in a vertical plane ; in the rest of the Stenothoide it is horizontal and
generally spoon-shaped, with the concave side uppermost. Epimeria macrodonta
is characterised by the long curved and sharp teeth on the body segments; while
Iphimedia hodgsoni has these so densely clothed with fine spines directed backwards
as to have a shaggy appearance. All the four species of /phimedia in the collection
are of very large size compared to the northern species, measuring from 20 to 45mm. in
length. Lastly, the remarkable development of the meral joints of the last three pairs
of pereeopods in the adult males of Seba antarctica, may be mentioned.

CLASSIFIED LIST OF ‘DISCOVERY’ AMPHIPODA.
HYPERIIDEA.}

FAM. VIBILIIDA, Crauvs.
Genus Viera, H. Milne Edwards.
V. propinqua, Stebbing.
FAM. CYLLOPIDA, Bovauuius.
GENUS CyLLopus, Dana.
C. magellanicus, Dana.
FAM. HYPERIIDA, Dana.
GeENus Hyperta, Latreille.
H. yaudichaudi, Milne Edwards.
H. macronyx, A. O. Walker (1906).

* © Southern Cross’ Paper, Journ. Linn. Soc., XXIX., p. 45 (1903).
+ For references to and descriptions of the Hyperiidea, see ‘‘ Bovallius, Monograph of the Amphipoda
Hyperiidea ” (Kongl. Svenska Vetenskaps-Akademiens Handlingar, Band 21 and 22, 1887 and 1889).

AMPHIPODA.

Genus Hyprrocus, Bovallius.
H. liitkenides, A. O. Walker (1906).

Genus Hypertens, Bovallius.
H., dilatata, Stebbing.
Genus EvutTHEMIsTo, Bovallius.
E. gaudichaudi, Guerin.
FAM. ANCHYLOMERIDA, Bovauutius.
Genus Evprimno, Bovallius.
E. macropa, Guerin.

GAMMARIDEA.
FAM. HYPERIOPSID, Bovauutus.

Genus Hypertopsis, G. O. Sars.
H. australis, A. O. Walker (1906).

FAM. LYSIANASSIDA, G. O. Sars.
GENUS CHEIRIMEDON, Stebbing.
C. fougneri, A. O. Walker.
C. hansoni, A. O. Walker.
Gmunus WALDECKIA, Chevreux (1906).
W. obesa, Chevreux, Expn. Antarctique Frangaise, p. 13.

Genus Aristias, Boeck.
A. antarcticus, A, O. Walker (1906).

GENUS ORCHOMENE, Boeck.
O. goniops, A. O. Walker (1906).

GENUS ORCHOMENELLA, G. O. Sars.
O. pinguides, A. O. Walker.
O. franklini, A. O. Walker.
O. chelipes, A. O. Walker (1906).

Genus OrncHomENopSIS, G. O. Sars.
O. rossi, A. O. Walker.

Genus Trypxosa, Boeck.
T. murrayt, A. O. Walker.
T. kergueleni, Miers.
GxrNus Uristxes, Dana.
U. gigas, Dana.
Gunus PoporrionipEs, A. O. WALKER (1906).

P. incerta, A. O. Walker (1906).

FAM. PHOXOCEPHALIDA, G. O. Sars.
Genus Harprnra, Boeck.
H. obtusifrons, Stebbing.

4 A. O. WALKER.

FAM. AMPELISCIDA, G. O. Sans.
Gunus AMPELISCA, Kroyer.
A. macrocephala, Lilljeborg.
FAM. STEGOCEPHALIDA, G. O. Sars.
Gmnus Evanpania, Stebbing.
E. gigantea, Stebbing.
FAM. LEUCOTHOIDA, G. O. Sars.
Genus LeucorHo®, Leach.
L. spinicarpa, Abildgaard.
FAM. STENOTHOIDA, G. O. Sars.
Genus ProsoLoweEs, Della Valle.
P. antarcticus, A. O. Walker (1906).

Genus Prosonrenta, A. O. Walker (1906).
P. typica, A. O. Walker (1906).

Genus THAuMATELSON, A. O. Walker (1906).
T. herdmani, A. O. Walker (1906).

FAM. OEDICERIDA, G. O. Sars.
GENUS OEDICEROIDES, Stebbing.
Oe. newnesi, A. O. Walker.
Oe. calmani, A. O. Walker (1906).
FAM. EPIMERIIDA, G. O. Sars.
GENUS EprmeriA, Costa.
E. inermis, A. O. Walker.
E. macrodonta, A. O. Walker (1906).

Genus Eprerrevia, A. O. Walker (1906).
E. macronyx, A. O. Walker (1906).

FAM. IPHIMEDIIDA, Sressrna.

Genus IpHimepia, Rathke.
T. pacifica, Stebbing.
I. echinata, A. O. Walker (1906).
T. longipes, A. O. Walker (1906).
T. hodgsoni, A. O. Walker (1906).

FAM. EUSIRIDAS, G. O. Sars (1895).
Genus Eusirus, Kroyer.

E. propinquus, G. O. Sars.
E. microps, A. O. Walker (1906).

FAM. CALLIOPIIDA, G. O. Sars (1895).
Genus OraAporna, A, O. Walker.
O. longimana, A. O. Walker.
Grnus AryLorpEs, Stebbing.
A, serraticauda, Stebbing.
Genus Sreppinera, Pfeffer.
S. gregaria, Pfeffer.

AMPHIPODA.

o1

Grnus PontoGENEtA, Boeck.
P. magellanica, Stebbing.
FAM. ATYLIDA, G. O. Sars (1895).
GENUS AtyLus, Leach.
A. walkeri, Stebbing (1906).
FAM. DEXAMINIDA, Sressinea.
GENUS PoLycHERIA, Haswell.
P. antarctica, Stebbing.
FAM. MELPHIDIPPIDA, Srepsine.
GENUS MerLpHipippa, Boeck.
M. macrura, G. O. Sars.
FAM. LILLJEBORGIIDA, Srepsrna.
Grnus LinLJEBorers, Sp. Bate.
L. dubia, Haswell.
FAM. PHOTIDA, G. O. Sars (part).
GENUS HapLocHerra, Haswell.
H. barbimana, G. M. Thomson.

GeENuS Evrystueus, Bate.
E. longicornis, A. O. Walker (1906).

FAM. SEBIDA, A. O. Watxer (1906).
GENUS SEBA, Stebbing.
Seba antarctica, A. O. Walker (1906).

FAM. ISCHYROCERIDA, Srepsina.
Genus HEMIJASSA, 0.
H, goniamera, A. O. Walker.
FAM. COLOMASTIGIDA, Srepsrne.
Grnus Conomastrx, Grube.
C. pusilla, Grube.

DESCRIPTION OF THE SPECIES.

Untess otherwise stated, the references to Professor G. O. Sars are to his ‘‘ Crustacea
of Norway,” Vol. I., Amphipoda, 1895; those to Mr. Stebbing (Rey. T. R. R.) are to his
‘Challenger’ Report; and to A. O. Walker, to the Amphipoda of the ‘ Southern Cross’
Antarctic Expedition, Journ. Linn. Soe., London, Zoology, Vol. XXIX. (1903),
pp. 38-64.

The classification of the species is, as far as possible, im accordance with that of
Professor G. O. Sars, in the “ Amphipoda of Norway.” After the completion of this
memoir (on October 30, 1906) I received, through the kindness of the author, the Rev.
T. R. R. Stebbing, F.R.S., a copy of his invaluable work on the Amphipoda Gammaridea,
written for “ Das Tierreich.” As this will be indispensable to all systematic workers on
the Amphipoda, and as it contains full references to all species described and published

6 A. O. WALKER.

up to May, 1906, I refer my readers to it where my references are insufficient. The
nomenclature of the genera and species has been corrected to correspond with it.
I have not thought it advisable to give synonymic lists of the older species, as I
have often found these to be sources of error, owing to mistaken identifications.
The following terms are used in the descriptions :—
“ Pleon ’”=metasome, G. O. Sars ; the first three abdominal segments.
“ Urus””=urosome, G. O. Sars ; the last three abdominal segments.

“ Ocular lobe” =lateral angle of the head.
“ Appendage ” =secondary or accessory appendage of the upper antenne.

In the peduncle of the antenne, the “ first joint” is the antepenultimate ; in the
limbs it is the basipodite. The measurements are from the tips of the uropods to the
base of the antennze, when the amphipod is straightened.

FAM. VIBILITDA, Cxaus.

VIBILIA PROPINQUA.
Vibilia propingua, Stebbing.

From lat. 54° 01'S., long. 170° 49’ E. (27 Dec., 1901) to lat. 69° S., long. 174° E.
(7 Jan., 1902); many specimens. The ‘Challenger’ specimens were taken in lat.
25° 30’ N., long. 130° E. It has recently been recorded by Mr. Stebbing from the Bay
of Biscay.*

The genus Vibilia has been partly revised by Herr Vosseler,t but his paper does
not include the following species :—

1892. 1. V. erratica, Chevreux, Bull. Soc. Zool. de France, 17™° année, pp. 32-35.
1896. 2. V. bovallii, Bonnier, Camp. du Caudan dans le Golfe de Gascogne, Ann. Université de
Lyon, p. 612, Pl. XXXYV., fig. 3.

~ Vatarondelies \ Cievrenx, Camp. scient. de 1Hirondelle (leans asl eemamIn

3

4. V. dentata ; S ss
25-

Parananones Amphipodes, pp. 125-154, Pls. XV., XVI.

1900.

Of these No. 1 is distinguished by the wrist of the second gnathopods being
without the usual process. Nos. 3 and 4 belong to Bovallius’ division, in which the
lateral angles of the last urus segment are not produced backwards. No. 3 is said to
be very near to V. viatrix, Bov., but distinguished by the presence of a rostrum
(which, according to Vosseler, occurs also occasionally in V. viatrix), the rounded form
of the epimeral plates of the first and second pleon segments, the partial coalescence of
the two last urus segments, and the great length of the carpal process of the second
gnathopods. No. 4 is characterised chiefly by the large size of the teeth on the palmar
margin of the first gnathopod. No. 5 has the angles of the last urus segment produced
in “deux petits prolongements latéraux, larges et arrondis.” In the present collection

* Trans. Linn. Soe. Zool., 2nd Ser., Vol. X., p. 31.
f Amphipoden d. Plankton Expn. 1 Teil. Hyperiidea, Mitt. Kéniglich. Nat. Kabinet, Stuttgart, 1901.

AMPHIPODA. 7

is a female V. propinqua, of 12mm., with seven or eight young, 3-5mm., which agree
with V. antaretica, Stebbing, thus confirming Vosseler’s opinion (vp. cit., pp. 118 and
fas

120, note). These were taken in the steamship ‘ Morning, lat. 67° 5
179° 30’ E.

S., long.

FAM. CYLLOPIDA, BovaAttivs.

CYLLOPUS MAGELLANICUS.
Cyllopus magellanicus, Dana.
From lat. 51° 58’ S., long. 170° 03’ E. (26 Dec., 1901) to “past Cape Adare ”
(11 Jan., 1902); several specimens ; length 12—14mm.

FAM. HYPERIIDA, Dana.

HyYPERIA GAUDICHAUDI.
Hyperia gaudichaudi, M. Edw.

W.Q.,* 25 Dec., 1902, 6 fm., one young; W.Q., 6 and 7 May, 1903, one female,
25min., one male almost as large, and an immature male, 16mm. ; W.Q., 16 June, 1903,
15 fm., one female, 10mm. ; W.Q., 5 May, 1904, 10 fm., one immature female and two
young.

HyYPERIA MACRONYX.T

(Plate 1, fig. 1.)
Hyperia macronyz, A. O. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 452.

S.E. of Coulman I., 22 Feb., 1904, six specimens, immature, length of largest
10mm. W.Q., 16 April, 1903, 5 fm., one specimen. W.Q., 18 May, 1903, 10fm. ;
W.Q., 1 Aug., 1903, 10 fm., eight specimens.

Hlead shorter than the first two segments. yes occupying the entire head
Segments all free; the three pleon-segments with a tooth on the hind epimeral angle.
Carpal process of the first gnathopods reaching the middle of the hind margin of the
hand, which is ovate, less than twice as long as wide, the hind margin conver and
jinely serrate. Carpal process of the second pair reaching considerably beyond the middle
of the hand ; the limb otherwise as in the first; branchiz of first pair oblong, wider
below ; of second pair, pyriform.

First and second perzxopods longer than the gnathopods : first joint a little wider
than the fourth, which is twice as wide and about two-thirds as long as the fifth, with
five long equidistant species on the hind margin; the fourth and fifth joints have their
hind margins finely serrate. Dactyli slightly curved, slender, about half as long as the
fifth joint.

Third pereopods : First joint subequal to the fifth, about twice as long as wide,

* W.Q. = Winter Quarters.

+ From the long dactyli of the perseopods.

VOL. Il. F

8 A. O. WALKER.

widening near the middle ; fifth joit half as long again and half as wide as the fourth,
its front margin finely serrate. Dactyh as in preceding pairs.

Fourth and fifth pereopods: First jomt narrower than in the third pair, and
the front margin of the fifth smooth. The fourth pair are subequal to the third and
about one-fifth longer than the fifth. Dactyli as in preceding pairs.

First uropods reaching to the end of the third, second a little shorter.

Third uropods: Peduncles broad, one-third longer than the rami, which are sub-
equal, wide at the base, and acutely pointed ; the outer edge of the outer ramus smooth
the rest unequally serrate.

Telson equilaterally triangular, barely reaching the middle of the peduncle of the
third uropods.

This species in the length of the peraeopods and the relative proportions of the
last three pairs approaches Parathemisto, with which it also agrees in the mouth-organs,
but the widely expanded and produced wrist of the first gnathopods does not agree with
either G. O. Sars’ or Bovallius’s* definition of that genus.

Length 10mm.

HyYPEROCHE LUETKENIDES.

(Plate 1, fig. 2.)
Hyperoche liitkenides, A. O. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 453.

Lat. 57° 25’ 30" S., long. 151° 43’ E.; one male, length 12 mm.

Like Hyperoche litkeni, Bovallius,t except in the following respects:—In the
second pair of perseopods (fourth pair of Bovallius) the hind margins of the fourth and
fifth joints are not serrate. In the third pair the fifth joint 7s curved.

The telson is triangular, with rounded apea, rather longer than the width at the base,
and reaching to the middle of the peduncles of the third uropods.

The mandibular palp has the third joint almost as long as the first and second
united as figured by Bovallius for ZZ. liitkeni. In this respect both species differ from
G. O. Sars’ figure of [. kréyeri, Bov. (HT. tauriformis (Sp. Bate and Westwoodf)], m
which the third joint is shorter than the second.

In the first pair of perseopods the hind margin of the fourth jomt is prolonged in
the form of a strong serrate tooth; in the second pair the tooth is smaller and not
serrate, but the curved portion of the end of the joimt between the tooth and the base

of the fifth joint is so.
HYPERIELLA DILATATA.
Hyperiella dilatata, Stebbing.

Young specimens, abundant at W.Q. from Nov. to July, length 8-Imm.

* Boyallius, Amphipoda Hyperiidea, Part 2 (1889), p. 129.

+ Bovallius, Amphipoda Hyperiidea, Part 2 (1889), p. 97, Pl. VIT.

{ British Sessile-eyed Crustacea, Vol. 2, App., p. 519.

§ Mr. W. M. Tattersall, who has kindly examined specimens of H. tawriformis from the W. of Ireland for
me, informs me that the palp in the male resembles Bovallius’s figure of H. liitkent, while that of the female
agrees with Sars’ figure.

AMPHIPODA. 9

KUTHEMISTO GAUDICHAUDI.
Euthemisto yaudichaudi, Guerin.
Abundant from lat. 54° 01' S., long. 170° 49’ E. to lat. 63° 04'S., long. 175° 43’ E.,
mostly youne—a female with ova measured 15mm.

FAM. ANCHYLOMERIDA, Bova tutus.
KUPRIMNO MACROPA.
Euprimno macropa, Guerin.

One specimen, length 16mm., 26 Feb., 1904.

FAM. HYPERIOPSIDA, Bova tivs.
HyPeriopsis ausTraLis. (Pl. 4, fig. 3.)
Hyperiopsis australis, A. O. Walker, Ann. and Mag. Nat. Hist. XVIT. (1906), p. 454.

W.Q., 16 June, 1903, 15 fm. ; one.

Differs from //. Véringii, G. O. Sars (Norweg. N. Atlantic Expn., p. 231), in the
following points :—

The lower margin of the head is oblique.

The first segment of the urosome has a deep dorsal depression; the second
seoment is the longest of the three.

The third joint of the first and second perzeopods is not quite twice as long as the
next two united, and is about the same width, i.e., the margins are parallel, the distal
three-fourths of its length.

In the last perzeopods the jointing is indistinct, the very long third (or fourth)
joint is finely serrate and spinulose.

The first and second uropods are biramous. In his definition of the genus Sars says
that they are “simple, two-jointed,” but as the rami cling closely together this might
easily be an oversight.

The single specimen was not dissected (nor, probably, was Sars’), but the
maxillipeds are evidently of the Gammarid type. Bovallius (Amphipoda Synopidea)
has placed the genus in his tribe of Synopidea under the family Hyperiopsidee.

FAM. LYSIANASSIDA, G. O. Sars.

CHEIRIMEDON FOUGNERI.
Cheirimedon fougneri, A. O. Walker.
W.Q., 8 Aug., 1902; No. 2 D., 4 fm.; one. W.Q., 1 Dee., 1902; Hut Point
(123), one young.
(HEIRIMEDON HANSONI.
Cheirimedon hansoni, A. O. Walker.

Cape Adare, 24 Feb., 1904; Laminaria roots, 13-20 fm. ; one, 4 mm. lone.

FY

LO A. O. WALKER.

WALDECKIA OBESA. (PI. 2, fig. 4.)

Waldeckia obesa, Chevreux. Expn. Antarctique Francaise (1906), p. 13.
Charcotia obesa, Chevreux, Bull. Soc. Zool. de France, Vol. XXX. (1906), p. 168.

W.Q., 17 May, 1902, two; 4 Oct., 1902, off Castle Rock (107), 3; 27 Aug., 1902,
two (one adult male); 5 March, 1903 (159), one large, one young; 10 March, 1903
(160), one large.

Female, length 18 mm.

Body tumid: First four side plates at least twice as deep as the segments, the
fourth wider at the lower margin than deep, and greatly extended behind to the hind
margin of the side plate of the third pereeopod ; this is large, convex, and subquadrate,
widest below, angles rounded. The posterior angle of the first pleon segment is
rounded ; that of the second acute ; the third has the hind margin elevated dorsally in
a blunt tooth, the posterior angle upturned and sub-acute, the hind margin of the
epimere hollowed out just above it, and thence convex. The first segment of the urus
is carinate, the hind margin dorsally elevated in a recurved point.

Head scarcely produced in front, a little longer than the first segment, speckled
with red; ocular lobe produced to an acute point reaching to the end of the first joint
of the upper antenne. yes large, dark, elongate-reniform.

Upper antennz a little longer than the head, reaching the middle of the flagellum
of the lower; first joint as lone as the flagellum, second very short, third almost
covered by the second ; flagellum twelve-jointed, the first jomt longer than the next
two, setose ; appendage seven-jointed, reaching beyond the middle of the flagellum.

Lower antenne : The first jomt the shortest, the second the longest, curved and
widening distally, the second and third together subequal to the twelve-joimted
flagellum. In the male this reaches to the urus.

Mandibles: Palp robust; first joint about half as long as the second, which is
rather longer than the third, the anterior margin of which is convex for one-third its
length, then straight and fringed with sete.

First maxille as in Socarnes vahlii (Kroyer), except the inner plate, which has
four or five unequal plumose setee.

Epistome with both lobes rounded.

Maaillipeds with the inner plates squarely truncate, with rather long setee on the
ends and inner margins.

First gnathopods » Side plates more than twice as deep as wide, oblong, with the
front margin obtusely angulated near the insertion of the first joint, angles rounded.
First joint wide, and as long as the remainder ; wrist shorter than the hand and wider
than its base. The hand is simple (not subchelate), tapering to the base of the strong
curved dactylus, and setose on the hind and distal half of the front margins.

Second gnathopods: First joint fully as long as the remaining joints together ;
wrist longer and rather narrower than the hand, the hind margin of which is a little
produced ; dactylus distinct.

AMPHIPODA. 11

First pereeopods: Side plates narrow, widening distally, curved. Coxopodite
distinct, about one-third the length of the side plate. First joint subequal to the next
two, widening distally ; third joint rather wider at the distal end than the first at the
same point ; second, third, and fourth setose, fifth spinous on the hind margin.

Second perzeopods: Like the first, except the side plates (see back).

Third pereopods: Side plates as deep as the leg is long, widening below,
the hind margin angulate below, the front rounded. First joimt wider than
long, with the hind margin excavate and setose above and obscurely crenate below ;
hind margin of the third joint produced to the middle of the next and terminating in a
spinous point ; the front margin of all the joints except the first is armed with short
spines.

Fourth pereopods: First joint subovate, very obscurely crenate behind.

Fifth pereopods: First joint much wider than that of the fourth pair, the hind
margin distinctly crenate in the middle.

First and second uropods: The peduncles as long as the outer rami, the inner
rather shorter.

Third uwropods: Rami rather longer than the peduncles, the outer rather the longer,
with spines on the outer and long setze on the inner margin.

Telson cleft nearly to its base, reaching to the middle of the rami of the third
uropods.

ARISTIAS ANTARCTICUS. (PI. 3, fig. 5.)
Aristias antarcticus, A. O. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 454.

W.Q., 28 Feb., 1902, Millurdo Bay, 20 fm., one, length 15 mm. ; D., 5 June,
1902, one smaller.

Body moderately compressed, without carinz or teeth.

Head shorter than the first segment; ocular lobe produced to the end of the first
joint of the upper antennee, rounded at the apex. yes large, dark, expanded
below.

Body-segments increasing in length backwards. First four side-plates about as
deep as the segments, the first concealed by the second; the fourth moderately pro-
duced behind; the fifth much wider than deep. Posterior angle of the third pleon
segment produced backwards, acute. First urus segment depressed in front ; second
and third almost concealed by the first, and perhaps coalesced.

Upper and lower antennz subequal, scarcely reaching the end of the third segment.

Upper antenne: First joint rather longer than the second and third, the lower
margin projecting distally ; second twice as long as the third, lower margin projecting.
Flagellum ten-jointed, the first joint setose, as long as the next three joints, which are
distally setose. Appendage five-jointed, the first the longest, the rest subequal.

Lower antenne : First joint twice as wide as long ; second and third subequal,
about three times as long as the first ; flagellum ten-jointed.

12 A. O. WALKER.

Mandibles as in A, neglectus, Hansen,* but the projection from the molar tubercle,
which appears to be membranaceous, is less prominent. The third joint of the palp is
straight.

First and second maxille# as in A. neglectus.

Mazillipeds as in A. neglectus.

First gnathopods: Side plates small, rather wider than deep. First joint as long
as all the rest, four times as long as wide. Wrist longer and wider than the hand,
unequally setose on the hind margin. Hand not subchelate, narrowing distally, the
front margin convex, the hind slightly concave, spinulose along its entire length, with
four spines at unequal intervals.

Second gnathopods: Side plates semi-oval, extending to about one-third of the first
joint. First joint subequal to the next three united, widening to about one-fourth of
its length from the distal end, then narrowing. Wrist longer and wider than the hand,
the hind margin densely setose ; hand with subparallel margins, both setose. Dactylus
well developed.

First and second pereeopods : Side plates rounded below, those of the second pair
obtusely angulated about the middle of the hind margin. The fourth joint is about
half as long and twice as wide at the distal end as the fifth; the hind margin of the
latter terminates in an acute angle.

The remaining pereeopods are subequal in length and structure, robust, the third
joint expanded, the fourth with both margins produced downwards; the hind margins
of the first joints in the third and fourth pairs are smooth, except the lower part, which
is obscurely crenate ; in the fifth pair the whole margin is serrate.

First and second uropods: Peduncles subequal to the outer rami, inner rather
longer ; all parts sparsely spinous. The first pair extend beyond the second and these
beyond the third.

Third uropods: Inner rami lanceolate, as long as the peduncle, and reaching to the
end of the first joint of the outer ; margins finely spinulose.

Telson about as wide at the base as long, cleft about two-thirds of its length,
divisions dehiscent, rounded.

Both specimens had the third and fourth perseopods turned up over the back.

ORCHOMENE Gontops.t (Plate 3, fig. 6.)
Orchomene goniops, A. O. Walker, Ann, and Mag. Nat. Hist. XVII. (1906), p. 455.
W.Q., 21 Aug., 1903 ; two specimens, probably immature ; length 5 mm.
Body-segments increasing in length backwards. /irst four side-plates deeper than
the segments, narrow. Third pleon-segment with a small postero-dorsal carina and hind
and lower margins straight, the former crenate, the posterior angle rather less than 90°.

* Vidensk. Meddel. 1887 (1888), p. 67.
t yervia, angle; &y,, face.

AMPHIPODA. 13

Head shorter than the first segment; ocular lobe broadly triangular, produced
beyond the end of the peduncle of the upper antenne. Eye moderately large, oval, dark.

Upper antenne : First joint three times as long as the next two united, naked.
Flagellum 13-14-jointed, the first jot as long as the next three, sparsely setose on
the upper side. Appendage 5-jointed, the first jomt the longest, the third the shortest.
Lower antennz rather longer than the upper ; peduncle reaching the end of the third joint
of the flagellum of the upper; first joint the longest, second the shortest. Mist
gnathopods: Side plates narrowed and rounded below; wrist two-thirds of the length
of the hand, which is about twice as long as wide, with parallel margins, setose; palm
rather oblique, convex, crenulate, defined by a spine. Second ynathopods as in Orchomene
humilis (Costa) [= O. batei, Sars]. Third pereeopods : Side-plates wider than the depth
in front, with the usual posterior lobe ; first joint about half as large as the side-plate,
deeper than wide ; hind margin convex, serrate, produced down to the middle of the
third joint ; this is much produced behind and downwards. The jifth perzeopods have
the first joint nearly twice as deep as wide, and longer than the rest of the joints, including
the dactylus, together, otherwise like the third pair; the dactyli of all the perseopods
are very short.

The jirst uropods are subequal in extent to the second, exceeding the third; the
peduncle is one-fourth longer than the subequal rami, all the parts very spinous on the
upper margins. Second pair less spinous. Pedunele in the third pair rather longer
than the outer ramus: inner ramus not nearly reaching the end of the first joint of the
outer, its inner margin minutely serrate. Telson entire, deeply concave above, the end
truncate with two setules: it extends beyond the end of the inner rami of the third
uropods.

The difference between the telson of this species and that of the female O. /winilis
is only one of degree, as the truncate margin is slightly concave.

ORCHOMENELLA PINGUIDES.
Orchomenella pinguides, A. O. Walker.

W.Q., March to October, 1902 ; ten, 143 fm. ; length 10 mm.

QO. FRANKLINI.
O. franklini, A. O. Walker.

W.Q., 15 June, 1902 ; D net, nine, various sizes, length of largest 6°5 mm.
O. cHELIpES. (PI. 4, fig. 7.)
O. chelipes, A. O. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 456.

W.Q., 28 Feb., 1902 ; eight., 10 fm.
Body moderately compressed ; first and second segments subequal to the head and
each other, remaining mesosome segments rather longer and subequal. First four side-

14 A. O. WALKER.

plates but little deeper than the segments. Hind margin of the epimere of the third
pleon segment forming a rounded right angle with the straight lower margin. First
urus segment as long as the remaining two, carinate ; second shorter than third.

Head: The ocular lobe reaching the end of the first joint of the lower antenne,
rounded at its apex. yes large, wide-oval, dark red in spirit.

Upper antenne: First jomt about three times as long as the next two, naked ;
third shorter than the second. Flagellum in the female 11-jointed, the first as long as
the next two, with a few long sete below. Appendage 4-jointed, the first twice as
long as the second, which is subequal to the third, the fourth minute, the whole very
sparsely setose.

Lower antenne slightly longer than the upper; flagellum 12-jointed, subequal to
the peduncle.

Mouth organs as in O. nana (Kr.). The mandibular palp strong, with the second
joint twice as long as the third.

First gnathopods: Side plates widening downwards, rounded in front, straight
behind. First joint almost as long as the rest united ; front margin of the wrist rather
shorter than that of the hand; hand rather narrower than the wrist, slightly curved,
the hind margin produced distally so as to form an imperfect chela with the dactylus ;
the oblique palm is finely pectinate and defined by two spies; the hind margins of
the third, fourth, and fifth joints are densely fringed with short sete.

Second gnathopods rather stout ; side plates oblong, widening below. First joint
about twice as long as the second, which is longer than the third; this has the hind
margin densely pilose ; wrist tumid, much longer and wider than the hand, the hind
margin convex, scabrous ; front margin straight, densely setose ; hand densely setose,
with a few strong curved and serrate spines over the insertion of the dactylus.

Second pereopods : Side plates moderately produced and angulate behind.

Third, fourth, and jifth pereeopods of similar structure, Increasing in size suc-
cessively ; the side plates of the third pair are wider than deep, and much larger than
the first joints. The first joints in the three pairs are wide and obscurely crenate
behind.

First uropods extending a little beyond the second, and these beyond the third ;
inner ramus of the third not reaching the last joint of the outer.

Telson barely reaching the end of the peduncle of the third uropods, deeply
notched.

Recognisable by the peculiar form of the first gnathopods.

ORCHOMENOPSIS ROSSI.

Orchomenopsis rossi, A. O. Walker.

This species was taken in enormous quantity throughout the year, and is doubtless
the one to which Mr. Hodgson refers in his “ Preliminary Report,” p. 398, as being
‘commonly taken 10,000 to 30,000 at a haul.” It is noteworthy that it has not been

AMPHIPODA. 15

taken either by the ‘ Discovery’ or ‘Southern Cross’ north of lat. 77° 50’. Male
specimens with the lower antennze developed in the manner supposed to indicate sexual
maturity are very scarce, yet in a gathering from Castle Rock Seal Hole, W.Q.,
143 fm. (no date), there are a number which, though only 15 mm. long, have the
flagella with 36 joints well furnished with calceoli; and from Hole 6, W.Q.,
23 Feb., 1903, 130 fm. (153), there is a probably adult male of 25 mm., which appears
to be the maximum size. There is some variability in the form of the third pleon
segment, the hinder angle of which is less rounded in some specimens, especially the
largest, than in others. Mr. Hodgson writes as follows :—

“This species was not regarded with favour when we were in Winter Quarters,
and it is a matter of considerable regret that its seasonal development was not looked
for ; its migration it was impossible to follow. It occurred first in considerable numbers
on the 17th May, 1902, when the winter was well advanced. On that occasion the trap
was hauled from 56 fathoms about 4.0 p.m. and then it was so dark that I was obliged to
return to the ship for a lantern. The trap contained about 10,000 of these amphipods.
A thousand individuals were counted, the volume ascertained, and this formed the basis
for the present estimate of number and for future occasions. Four fish were in the
trap, one of them had been reduced to an absolute skeleton ; on another the amphipods
hung by their ‘ teeth’ in a compact mass, completely concealing their victim. Its skin
had disappeared, and | judged also about a millimetre of flesh, but the animal was still
alive ; the other two fish were presumably waiting their turn.

“From that date until 25th October, 1902, this species was taken generally in numbers
varying between 10,000 and 30,000 at a haul, and this at all depths to 125 fm., which
was our practical limit for ordinary work. Two or three times a trap was used in 173
fm.,in July and August 1902, but not many amphipods were obtained—100 or so at a
time. These animals swarmed over the bait to such an extent as to make it obvious
they kept other animals away ; otherwise the number of other animals captured was
unaccountably small. Under these circumstances the presence of this amphipod was
regarded as a nuisance, and as a large stock had been preserved, further captures were
generally left on the ice at the mouth of the hole. My experience at the holes soon
made it perfectly clear that there was no small mortality among the seals through their
not being able to get to a breathing-hole in time during their wanderings, and thus
affording a substantial food supply for predaceous crustacea. I came to the conclusion
that these amphipods travel about the sea bottom in vast hordes in search of food, a
conclusion further accentuated by the fact that from 25th October to 27th December,
1902, they completely disappeared from all the traps; stationary traps were not used
during the same period of 1903. From October to January is the seals’ breeding season,
and at this time they remain, for the most part, close inshore. The place nearest the
ship where they congregated most was among the pressure ridges at Pram Point.
These ridges are formed by the ‘ Barrier’ ice intruding into the Sound between White
Island and Cape Mackay and pressing against the land at Pram Point. As the ice did

VOL, III. G

16 A. O. WALKER.

not go out during the season of 1902-3, the principal ridge became more than a mile
long, the ice being pressed up to a height of twenty or thirty feet at the point of
greatest pressure. Considering that the mortality among the seals would be much
increased during the breeding season, it occurred to me that the amphipods might have
migrated close imshore, more especially to Pram Point, as an area where a super-
abundant supply of food might be obtained. I went to investigate this matter, but the
seals had made their holes among the irregular blocks of ice piled up in a confused
manner. I found that the hole from the surface usually led on to a platform some
two or three feet below ; the hole which completed the passage through the ice had no
relation to the one above, and was generally at some distance from it, and quite
invisible from my point of view. As it turned out, I could not get a trap down any of
the holes, so that the presence of these amphipods on the breeding-grounds of the seals
is uncertain, and no explanation of their desertion of the traps in deeper water is
forthcoming.”

TRYPHOSA MURRAYI.
Tryphosa murrayi, A. O. Walker.
T. adaret, A. O. Walker.

This is another abundant species, though not nearly so much so as O. rossi. The
largest female measured 30 mm. It appears to occur from Cape Adare to lat. 77° 50’,
and was taken at the Winter Quarters throughout the year.

The examination of a large number of specimens has convinced me that the
characters relied upon for the separation of 7. murrayi and T. adarei, viz., the form of
the hind margin of the third pleon segment and the carina on the first urus segment
are very variable, and I have therefore united them.

TRYPHOSA KERGUELENI.
Lysvanassa kerguelent, Miers.
Hippomedon kerguelent (Miers), Stebbing.
Hoplonyx kergueleni (Miers), A. O. Walker.
Cape Wadsworth, 8-15 fm., 15 Jan.,1902, one, small ; W.Q., 15 June, 1902, one,
length 13 mm.; W.Q., 20 Sept., 1902, Castle Rock, 143 fm., three.

URISTES GIGAS.
Uristes gigas, Dana.
Tryphosa antennipotens, Stebbing.

Past Cape Adare, 11 Jan., 1902, one specimen.

PODOPRIONIDES.
Podoprionides, A. O. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 457.

Resembles Podoprionella, G. O. Sars, in the chelate first gnathopods and the
deeply serrate first joints of the last three perzeopods, but differs in the less compact

AMPHIPODA. 17

body, the structure of the mandibular palp and of the outer ramus of the third uropods.
From Podoprion, Chevreux,* it differs in having the first joint of the fourth and fifth
pereopods serrate like the third.

PODOPRIONIDES INCERTA. (PI. 5, fig. 8.)

Podoprionides incerta, A. O. Walker, Ann. and Mag. Nat. Hist. XVII. (1906), p. 457.

W.Q., 29 Aug., 1902, Hole 12, D net, one specimen ; length 2 mm.

Body not very compact ; the anterior side plates small.

Upper antennee reaching a little beyond the peduncle of the lower; appendage
2-jointed, the first twice as long as the second, which has a tuft of very long sete at
the extremity.

Lower antenne: Peduncle stout, margins of third joint produced. Mandibular
palp with the third joint more than half as long as the second, narrow, pectinate.

First gnathopods : Side plates less than half the length of the first joint, rounded
in front, straight behind, with a notch and a spine above the angle. First joint
rather longer than the remaining five, widening distally ; second and _ third
joints subequal; wrist subequal to the hand; the hind margin of the hand is short,
conver and prolonged in a spine-like process, which is slightly curved invards to meet
the point of the curved dactylus, forming a completely chelate joint ; palm very oblique,
smooth,

Second gnathopods: Side plates oblong, about twice as deep as wide, angles
rounded. First joint hardly as long as the next three ; second longer and wider than
the third; wrist about twice as long as the hand, which is oblong, setose on both
margins, palm transverse. The last three pairs of pereeopods have the first joints
broadly ovate, the hind margins deeply serrate, as in Podoprion, Chevreux, and
Podoprionella, Sars.

Uropods : First and second subequal in extent and scarcely exceeding the third
pair; the outer ramus in this pair has two subequal joints and is but little longer than
the inner. The telson could not be made out.

The single specimen was not dissected ; the mouth-parts therefore could not be

described. -

FAM. PHOXOCEPHALIDA, G. O. Sars.
HARPINIA OBTUSIFRONS.
Harpinia obtusifrons, Stebbing.

W.Q., Oct.-Noyv., 1902, Hut Point; three, length of largest 6 mm. W.Q., 15
June, 1902, D net, twelve young.

* Mémoires de la Société Zool. de France, Tome IV. (1891), p. 6, Pl. I.
G

bo

18 A. O. WALKER.

FAM. AMPELISCIDA, G. O. Sars.

AMPELISCA MACROCEPHALA.

Ampelisca macrocephala, Lilljeborg.

Coulman Island, 13 Jan., 1902, 100 fm. ; two males, length 18 mm.

In these specimens the upper and lower antennz appear to be subequal, and reach
to the urus. They (especially the upper) are therefore considerably longer than in the
northern form as figured by G. O. Sars. The lower margin of the first joint of the fifth
pair of perseopods is more truncate than in the female specimen in the ‘ Southern
Cross ’ collection.

FAM. STEGOCEPHALIDA, G. O. Sars.

EUANDANIA GIGANTEA ?
Euandania gigantea? Stebbing.

W.Q., 20 Aug., 1903, Hole 12, D net; one specimen, length 9 mm.
Probably a young specimen ; not dissected.

FAM. LEUCOTHOIDA, G. O. Sars.

LEUCOTHOE SPINICARPA.

Leucothoé spinicarpa, Abildgaard.

W.Q., 13 Sept., 1902, two; 5 Nov., 1902, one; 11 Nov., 1902, one; 28 Noyv.,
1902, one ; 8 Sept., 1903, two; 30 Sept., 1903, one.

I am unable to see any difference between these specimens and the European and
Ceylon forms. The largest measured 15 mm.

FAM. STENOTHOID., G. O. Sars.
PROBOLOIDES ANTARCTICUS. (PI. 5, fig. 9.)
Proboloides* antarcticus, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 13.

W.Q., from Feb. to Dec., 1902, sponges, Hut Point, ete.

Female: Kpimeres of the third pleon segment with straight hind and lower
margins, forming a rounded subrectangular posterior angle. Ocular lobe not very
prominent, subrectangular. //ve round, colourless in spirit.

* There can be little doubt that Dr. Della Valle is right in holding that Probolium polyprion, Costa, was a
true Stenothoé. The very nearly allied Stenothoe gallensis, A. O. Walker, certainly is so, the mandibles having
no palp and the lobes of the maxillipeds being separate. In Proboloides antarcticus the expansion inwards and
distal prolongation of the joint which corresponds to the outer lobe of the maxilliped are sufficiently developed
to form a rudimentary lobe. A similar form is shown by Stebbing in his figures of Metopa on Pls. XL. to XLVI,
and as all these species have mandibular palps, and the inner or basal lobes of the maxillipeds distinct, they should
now be included in Probolozdes, Della Valle, with the exception of M. ovata, which, from its two-jointed mandibular
palp, might be referred to Proboliella but for the narrow first joints of the peropods.

AMPHIPODA. 19

Antenne subequal, as in P. (Probolium) gregarium (G. O. Sars) ; no appendage.

Mouth organs as in P. gregarium.

Maxillipeds with the inner lobes very small and separate, the outer (masticatory)
represented by a dilation and distal prolongation of the inner margin of the joint.

First gnathopods : “Wrist subequal in length to, but wider than, the hand ; the hind
margins of both convex and setose, otherwise as in P. gregariuin.

Second gnathopods: Side-plates with the front and lower margins forming a
continuous curve, hind margins almost straight. First joint as long as the next four ;
third joint rather acutely produced behind ; wrist with a rounded process; margins of
the hand subparallel ; hind margin subequal to the palm, which is defined by a small
tooth and two spines.

First and second pereopods resembling those of P. gregarium, the second being
stouter and more spinous than the first, but the side-plates are more rounded in front.

Third pereopods: The posterior lobe of the side-plate is suboval and considerably
produced downwards. The concave hind margin of the narrow first joint is prolonged
almost to the end of the second, terminating in a divided lobe.

Remaining perzopods as in P. gregarium.

The second uropods are subequal in extent to the third, the peduncle subequal to
the inner ramus, which is almost twice as long as the outer; this has two spines, the
inner and peduncle several.

Third uropods : The peduncle is shorter than the ramus and has five spines; the
first joint of the ramus is subequal to the second and has three spines.

The ¢elson reaches the end of the peduncle of the third uropods and has three
spines on each margin.

Length, 3°5 mm.

The male is considerably larger than the female. Upper antennz reaching to the
middle of the flagellum of the lower. Pedunele of the lower twice as wide as that of
the upper, the second joint as long as the flagellum, which is 12-jointed, the first
joint as long as the next three.

First gnathopods: Wrist considerably longer and but slightly wider than the
hand.

Second gnathopods: Side-plates rounded in front, hind margin concave, the
posterior part of the lower margin irregularly serrate. First joimt rather longer than
the next three; second with a prominence on the front; wrist produced behind.
Hand as long as the three preceding joints, subtriangular, hind margin shorter than
the front and ending in a sharp tooth ; palm deeply excavate, with a central tooth and
a denticulate ridge near the base of the dactylus.

In a younger male the palm is less deeply excavate, the central tooth wider,
blunter, and denticulate, and the ridge as wide as the excavation.

Associated with this species were two or three females characterized by the concave

lower margins of the side-plates of the second pereopods.

20 A. O. WALKER.

There are other slight differences, such as the greater relative width of the first
joint of the upper -antennze ; more slender gnathopods; the third joints of the fourth
and fifth pereeopods more acutely produced, etc. It is possible that it might prove to
be a distinct species if the males were known.

PROBOLIELLA.
Proboliella, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 13.

Mandibles with a two-jointed palp.

First mazille with a two-jointed palp.

Mazillipeds with the inner plates divided to the base; the outer more or less
developed.

Second pereopods not stronger than the first ; third pereeopods with a narrow first
joint ; fourth and jifth with an expanded first joint.

Ps typos, ©) (PL6 hesa09)
P. typica, A. O. Walker, Ann. and Mag, Nat. Hist. XVIIT. (1906) p. 14.

W.Q., Hut Point, 11 Nov., 1902, one; 13 Oct., 1902, one; 18 Feb., 1904, one.
All females. .
Female—

Body tumid. Posterior angle of the third pleon segment produced and rounded.

Hye small, round, colourless in spirit.

Upper antenne without an appendage, reaching to the middle of the flagellum of
the lower ; the third joint half as long as the second; flagellum seven-jointed, as long
as the two last joints of the peduncle.

Mandibles bent downwards from the base of the palp and narrowed towards the
coarsely toothed cutting edge; the palp more than half the length of the mandible ;
the first joint less than one-fourth as long as the second.

Maaillipeds: Inner plates divided; outer distinct, though narrow; first and
second joints of the palp subequal, the third longer.

First gnathopods : Wrist shorter and narrower than the hand ; palm very oblique,
about as long as the rest of the hind margin, spinulose, and defined by two or three
long spines.

Second gnathopods : Side-plates oblong, convex in front, straight behind, the angles
rounded with a small tooth. First joint strong, as long and more than half as wide as
the hand, fringed with setae before and behind ; third joint produced behind to a very
acute point, which extends a little beyond the carpal process. Hand subelliptical,
the palm longer than the rest of the hind margin, convex, spinulose, and defined by a
strong tooth, beyond which is a smaller tooth and a group of spines.

First pereopods: Side-plates oblong, angles rounded, margins parallel; first

AMPHIPODA. 21

joint curved, oblong, almost as long and three times as wide as the next three; third
and fifth subequal, fourth rather shorter; dactylus slender, two-thirds of the length
of the preceding joint.

Second pereopods: Side-plates subtriangular, front margin straight, lower and
hind margins convex. The legs as in the first pair.

Third perzopods: First joint narrow, oblong, straight.

Fourth and jifth pereopods alike ; first joint oval, deeper than wide, hind margin
smooth.

The wropods are subequal in extent and sparsely spimous; the peduncle of the
third pair is subequal to the first joint of the ramus, which is also subequal to the
second joint.

Telson not reaching the end of the peduncle of the third uropods, narrowing
rather abruptly to a point with two spines on each side before the middle and one
beyond.

Length, 3 mm.

THAUMATELSON. *
Thaumatelson, A. O. Walker, Ann. and Mag. Nat. Hist. XVIIT. (1906), p. 15.

General characters of Metopa.

Palp of the first maaille two-jointed.

First gnathopods distinctly subchelate.

Telson large, entire, oval and set in a vertical plane on its longer edge.

T. HERDMANI. (PI. 7, fig. 11.)

. herdmani, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 15.

W.Q., Oct., 1902; 8-net, Hut Point; from Sponges. Gne spec. W.Q., 13 Feb.,
1904; D-net, Hut Point; one.

Body as in Metopa: the fourth side-plate unusually large, covering the bases of
the last three pairs of perzeopods. The last two pleon segments with a postero-dorsal
tooth. Segments of the urus coalesced.

Antenne: subequal, longer than the head.

Upper antennze: First joint longer than the second, which is rather shorter than
the third, and has the upper margin produced ; there is no appendage. Flagellum
shorter than the peduncle.

Lower antenne : Peduncle subequal to that of the upper, second and third joints
subequal and together longer than the flagellum.

Mawillipeds: Inner lobes reaching half-way up the narrow outer lobes, apparently
divided rather further down than in Metopa; outer lobes, as in Proboloides, a mere
slight expansion of the inner margin of the basal joint, which is produced distally half
the length of the next joint, which, as well as the remaining joints of the palp, is short

[Rectius Thaumatotelson—Eb. ]

22 A. O. WALKER.

and wide ; the third joint expanded distally ; dactylus wide at the base, the imner
margin pectinate.

First gnathopods: First joint straight, subequal to the next four; second shorter
than the third, which narrows distally to a rounded point; wrist triangular, about half
as long as the hand, which is subquadrate, with transverse, rather convex, palm as
long as the hind margin and defined by a group of spines.

Second gnathopods: First joint straight, widening distally, almost as long as the
next four; third joint oblong, ending behind in a blunted acute angle; wrist produced
behind a little beyond the base of the hand ; this is subtriangular, nearly twice as long
as the width at the palm, which is the widest part; front margin straight; distal half
of hind margin slightly concave, ending in a tooth behind which is a short and a long
spine defining the transverse, slightly convex and spinulose palm.

First and second pereeopods: Similar; all the joints narrow. Side-plates of the
first pair oblong, about twice as deep as wide, the angles rounded ; those of the second
broadly subtriangular, more rounded behind than in front, the lower margin slightly
concave or sinuous.

Remaining perzeopods resembling the first and second, the first joints narrow.

First uropods extending beyond the second, the rami subequal, shorter than the
peduncle ; in the second pair the upper ramus is shorter than the lower.

The single ramus of the third uropods is subequal to the peduncle, the first joint
rather longer than the second.

Telson as described above.

Length 2°5 mm.

FAM. OEDICERIDA, G. O. Sars.

OEDICEROIDES NEWNESI.

Oediceros newnesi, A. O. Walker.

5 June, 1902, two; length of female with ova, 7mm. W.Q., 15 June, 1902,
six young. Tent Island, 3 Jan., 1904, 20 fm., one.

A better mounting of the mandible than was effected with the ‘Southern Cross’
specimen shows that the molar tubercle is well developed, with a toothed grinding
surface. It must therefore be referred to the genus Oediceroides Stebbing.

The mandibular palp has the second joint wider and about one-fourth longer than
the third, being widest about one-third of its length from the base.

OE. caLMANI. (PI. 6, fig. 12.)
Oe. calmani, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 15.

Coulman Island, 13 Jan., 1902, 100 fm., two females. Flagon Point, 23 Jan., 1902,
one young. Barrier, 29 Jan., 1902, 100 fm., one.

AMPHIPODA. 23

Female: Body scarcely compressed laterally. Mesosome segments very short,
subequal, the first with a transverse fold. First pleon segment about twice ne long,
the second shorter, the third much longer than the first ; the last mesosome and first
two pleon segments with a dorsal tubercle near the middle; the third pleon and first
urus segments with a shallow carina; hind margin of the third pleon segment rounded.
First four side-plates as deep as the segments.

Head: Rostrum shorter than the rest of the head and reaching the end of the
first joint of the upper antenne, the lower margin scarcely concave ; the front sulcate,
not carinate. Eyes contiguous, occupying the greater part of the rostrum, varying from
red to brown.

Upper antenne not quite reaching the end of the second joint of the lower; the
first joint rather longer and twice as wide as the second, widening distally ; the second
twice as long as the third; first and second with tufts of plumose sete. Flagellum
ten-jointed, shorter than the peduncle.

Lower antenne: First joint wider than long, setose ; second stout, longer than the
third, which has a long spine near the middle and another at the distal end, both on
the lower margin.

Mandibles: Primary cutting edge with two short blunt teeth, secondary with a
long and a short tooth, molar tubercle bicuspidate ; first joint of the palp very short
and obconical; second subequal to the third in length, but more than twice as wide
near the base, both joints with long spine-like setz on the front margin.

Third perxopods: First joint oblong-oval, the front margin somewhat produced,
both margins with long sete, on the distal half; third joint almost as wide as the
first, densely setose.

Fourth perzeopods : First joint ovoid, the hind margin denticulate, sparsely setose ;
the front margin with longer setze which are plumose at the lower angle, otherwise as
in the third pair. The dactyli in all the perzeopods except the last (which are broken
in all the specimens) are almost as long as the fifth joints.

The gnathopods and rest of the animal agree with G. rostrata, Stebbing, from
which species this differs in the conspicuous eyes, the different form and proportions
of the rostrum, mesosome segments, first joint of the upper antennz and second
joint of the mandibular palp.

Length of female 30 mm.

FAM. EPIMERIID, G. O. Sars.

EPIMERIA INERMIS. (PI. 8, fig. 13.)
Epimeria inermis, A. O. Walker.
Jan. 22, 1902, 500 fm., two females, length 35 mm.; W.Q., 14 July, 1905, Hole 10,
107 fm., one dissected; W.Q., 2 and 4 Sept., 1903, one; W.Q., 8 Sept., 1903, one
young.

VOL, III, H

24 A. O. WALKER.

As the single specimen in the ‘Southern Cross’ collection was not dissected, the
following additional details are given. The specimen from which they are taken was not
full grown, and differs from the larger in the absence of the prominent convexity of the
lower part of the fifth side-plate and of the dorsal carina, except on the third pleon
segment.

Upper antenne: First joint of the peduncle longer than the remaining two,
swollen at the base on the lower margin; second nearly twice as long as the third ;
both have the upper margin produced and notched. Flagellum 28-jointed.

Lower antennze: Basal joint produced on the inner side beyond the first joint, the
upper margin in both forming an acute tooth ; second joint rather longer and thicker
than the third, the upper margin of which is produced and notched.

Mandibles: The palp stout, the second joint longer than the third, otherwise the
mouth organs and maxillipeds are nearly as in /. cornigera (Fabr.).

Gnathopods nearly resemble those of £. cornigera; the hand of the second pair is
shorter and wider at the distal end than that of the first, and is finely denticulate at
the rounded and spinous palmar angle.

Third pereopods: Side plates rhomboidal; first joint with a long tooth-like
process directed downwards from the upper part of the hind margin, which terminates
in a sharp tooth.

Fourth pereopods like the third, except the side plate.

Fifth pereopods: Side plates rather wider at the top than the widest part of the
first joint, narrowing downwards ; first Joint expanded above, narrowing abruptly near
the middle, whence the hind margin curves outwards and ends in a tooth.

First uropods: Rami subequal, longer than the peduncle, narrow lanceolate,
fringed with short spines on both margins.

Second wropods : Inner ramus not reaching the end of the first uropods ; outer less
than half as long and much narrower than the inner.

Third wropods not reaching the end of the longer ramus of the second pair,
broadly lanceolate, subequal, longer than the peduncle, which has a prominent tooth.

Telson reaching to the base of the rami of the third uropods, tapering considerably
and notched at the tip.

Length of the specimen described, 25 mm.

EPIMERIA MACRODONTA. (PI. 8, fig. 14.)
Epimeria macrodonta, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 16.

Jan. 22, 1902, 500 fm., three; W.Q., 4 Sept., 1903, Hole 12, one.

All the segments of mesosome and pleon, with the exception of the first two
segments, of which the first is twice as long as the second, armed with lateral teeth,
increasing in length backwards, with longer dorsal teeth, curved and directed upwards
and backwards ; those of the last mesosome and first two pleon segments the longest.

AMPHIPODA. 25

First two segments of the urus with an upright dorsal tooth, that on the first segment
the longer; the third segment with a lateral carina, which is turned up in a sharp
tooth. First three side plates narrow, acutely pointed below, the first straight, second
and third curved; the hind margin of the fourth forms an irregular crescent with
acute points; the fifth has a long acute tooth directed backwards and outwards,
reaching the hind margin of the sixth segment; the sixth has a small tooth: the
seventh unarmed. Posterior angles of the epimeres of the pleon segments produced
and acute.

Head: Lower margin of the ocular lobe produced forward in an acute tooth.
Rostrum almost horizontal, slightly decurved, and much longer than the rest of the
head. Kye large, round-oval, almost filling up the ocular lobe, colourless in spirit.

Upper antennee shorter than the lower ; first joint with a subequal distal tooth on
each side, reaching nearly to the distal end of the lower margin of the second joint,
which is subequal to the first, and has two long subequal distal teeth on the upper side,
reaching to the seventh joint of the flagellum; third joint about half as long as the
second, with a small distal tooth on the lower margin. Flagellum 32-jointed, slender.

Lower antenne: Basal jot with four or five unequal teeth ; first joint very
short; second and third more than twice as long. subequal, the former with a small
distal tooth below. Flagellum slender, reaching in the largest specimen to the fifth
segment.

Mouth organs and maxillipeds as in E. cornigera.

First and second gnathopods almost alike, more slender than in FE. cornigera, and
almost exactly like those of /. parasitica, M. Sars.

First and second pereopods: First joint subequal to but wider than the third ;
fourth joint about half as long as the third; fifth considerably longer than the
fourth.

Third pereopods: First joint rather longer than and twice as wide as the third,
the hind margin concave, with a rounded protuberance at the proximal end and a
large, very sharp tooth at the distal end directed backwards ; front margin concave in
the middle; front margin of the second joint produced downwards in a small tooth ;
third joint acutely produced behind.

Fourth pereopods: Hind margin of the first joint convex in the middle, otherwise
like the third pair.

Fifth pereopods: First joint wider than that of the fourth pair, the margins more
convex above, but the hind one concave above the strong and sharp distal tooth ; front
margins of first and second joints not produced.

The wropods are all subequal in extent ; the second pair has the outer ramus one-
third shorter than the inner; in the first and third pair the outer rami are scarcely the
shorter ; the peduncles of the third pair have the upper margins produced behind in an
acute tooth, and are about one-third of the length of the rami; these are long and
narrow, lanceolate, with a few small spines on both margins.

H 2

26 A. O. WALKER.

The telson narrows distally, the sides are slightly convex, and the divisions formed
by a notch extending to about one-third of the length are subacute.

Length 33 mm.

This species has a superficial resemblance to Acanthozone (Boeck.*), from which it
differs in the shape of the head, and Acanthechinus (Stebbing), from which it differs in
the head, mandibles, gnathopods, etc. Both these genera have the telson entire.

EPIMERIELLA.
Epimeriella, A. O. Walker, Ann. and Mag. Nat. Hist. XVIIT. (1906), p. 17.

Body smooth, without dorsal teeth, except in the first segment of the urus.

Head with a very small rostrum.

Fifth pair of side plates small, oblong, wider than deep, without a projecting process.
Mandibles with the molar tubercle imperfectly developed.

Third and fourth pairs of perseeopods much longer than the fifth.

Otherwise like Epimeria.

EPIMERIELLA MACRONYX.T (PI. 9, fig. 15.)
Epimeriella macronyz, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 17.

W.Q., 29 May, 1903, Hole 4, 5fm., two; W.Q., 1 June, 1903 ; Hole 8, 10 fm.,
three; 26 Feb., 1904 (269), one. This last measured 25 mm.; the rest were young,
measuring only 6 mm.

Head slightly produced in front. yes large, round, oval, prominent, colourless
in spirit.

Mesosome smooth, first and third segments subequal, and much longer than the
second ; remaining segments increasing in length successively. First three side-plates
about as deep as,the segments, narrow, convex, and pointed below, fourth deeper than
the others, narrowing below in a curved point, with the upper posterior angle produced
under the fifth side-plate in an acute tooth; fifth, small, transverse, oblong, with
rounded ends.

Pleon with an obscure dorsal carina; hind and lower margins of the third
seoment straight and forming a right angle.

First segment of the wrus dorsally depressed in front, and with a postero-dorsal
tooth.

Upper antennee: First joint more than twice as long as, and much wider than, the
second ; third shorter than the second and subequal to the first joint of the flagellum,
which has about twenty joints.

Lower antenne subequal to the upper; first joint very short; second and third
subequal, barely reaching to the end of the second joint of the upper.

Mandibles : Molar tubercle imperfectly developed ; primary and secondary cutting

* Skandinavske og Arktiske Amphipoder, 1876, p. 229; also G. O. Sars.
t From the great length of the dactyli of the third and fourth peropods.

AMPHIPODA. 27

edges dentate ; spine row long, of about twenty spines; the palp, which is set on in
front of the middle, is longer than the mandible; the first joint about one-third as
long as the second, which is subequal to the third. One of the mandibles appears to
be without a secondary cutting plate.

First maxille: Inner plate with about 12 plumose setze on its inner margin.

First gnathopods : First joint stout, rather longer than the side-plate, and subequal
to the wrist and hand united ; these are subequal to each other, the wrist rather the
wider ; the hand is oval, the palm undefined, pectinate ; the whole hind margin sparsely
and unequally spinous. Dactylus with 5 spines on the inner margin.

Second gnathopods are like the first, except the palm, which is more transverse, and
about half as long as the rest of the hind margin.

Second perxopods : Side-plates reaching below the second joint. First joint narrow,
oblong, subequal to the third and fourth united; third rather longer than the fourth,
and shorter than the fifth. Dactylus continuous with the fifth joint, as long as the
third, and slightly curved.

Third and fourth pereeopods subequal: First joint oblong, twice as long as wide ;
third joint half as long as the first, acutely produced behind ; fourth joint subequal to,
and fifth rather longer than the first. Dactylus very long, about one-fifth longer
than the fifth joint, and tapering very gradually. These two pairs appear to be
generally carried elevated over the back. In the largest specimen (25 mm.) the
dactyli are not quite so long relatively.

Fifth perzopods are considerably shorter, and the first joint wider, than the third
and fourth; hind margin of the first joint convex, obscurely serrate, and produced
downwards in a rounded lobe almost to the middle of the third joint; this is
much produced behind, and is a little shorter than the fourth, which is as long as the
dactylus and shorter than the fifth joint.

First and second uropods: The rami longer than the peduncles, the outer shorter
and narrower than the inner.

Third uropods: Rami nearly twice as long as the peduncle, subequal, the outer
the narrower, with fine spines on both margins.

Telson, reaching to about one-fourth the length of the rami of the third uropods,
deeply notched at the end, with a minute notch on the tip of each division.

The above description, with the exception of that of the external characters of the
animal as seen without dissection, is taken from a young specimen 6 mm. long.

FAM. IPHIMEDIID®, Sreserne.

IPHIMEDIA PACIFICA.
Iphimedia pacifica, Stebbing.
W.Q., 20 Feb. 1902, 20 fm., one; 14 Jan., 1903, 130 fm., one, young, about
8mm.; 14 July, 1903, 130 fm. one, length 24 mm.; 30 Sept., 1903, one, length
20 mm.; two on 4 Sept., 1905, one, length 30 mm.

28 A. O. WALKER.

The tooth on the first joint of the upper antennz is much longer in the large
specimens than is shown in Stebbing’s figures. This is probably only a matter of age.

IPHIMEDIA ECHINATA. (PI. 10, fig. 16.)
Iphimedia echinata, A. O. Walker, Ann. and Mag. Nat. Hist. XVIIT. (1906), p. 150.

W.Q., 24 Sept., 1902, Hut Point, one, large ; 24 Aug., 1903, Hole 12, D-net, three,
large, 30 mm., and about twenty-five, young ; 26 Sept., 1903, Hole 12, D-net, one, about
45 mm. long and 15 mm. across the back.

First segment of the mesosome longer than the second ; the next four segments are
longer than the second and subequal; the posterior angles of the first two are almost
right angles, and of the next four acute. The fifth segment has sometimes a few small
teeth on the hind margin ; the sixth has more, and the seventh is dorsally depressed,
and is longer than any of the other segments in the middle, but greatly narrowed down-
wards, with the hind margin more coarsely dentate. The pleon segments have
strongly dentate, dorsal carine, with smaller teeth on each side, and on the hind
margins ; the posterior angle of the second is acute and upturned, and that of the third
similar, but longer, and with a much longer curved tooth above it. The first urus
seoment is as long as the two next united, and has a dorsal depression followed by a
group of upright teeth; the second and third are smooth, except for a tooth on each
side of the telson. The first three pairs of side-plates narrow downwards to a point,
the second and third curved; the fourth, fifth and sixth have a strong tooth with
serrate edge directed outwards. The number of teeth appears to vary considerably in
different specimens.

Head: Rostrum as long as the rest of the head, acute, decurved ; ocular lobes
rounded ; eyes prominent, round, colourless.

Upper antenne: First jomt with two distal teeth on the upper side ; second joint
with a serrate tooth reaching almost to the end of the first joint of the flagellum on the
upper margin, and a short one on the lower; third joint short. In a young specimen
a rudimentary appendage was seen, but in a larger (though not adult) this was only
indicated by two sete. First joint of the flagellum as long as the next three.*

Lower antenne subequal to the upper; second and third joints subequal; the
three peduncular joits have the upper margins produced; the basal joint has a
prominent curved tooth on its upper side.

Mandibles, without molar tubercles, different; one, having the simple cutting
edge oblique, obscurely dentate, with a tooth at the lower angle; the other having the
cutting edge more strongly dentate, with a peculiar secondary apparatus in the form of
a hollow chitinous cylinder with a smooth periphery. First joint of the robust palp
shorter than the second, which is subequal to the third.

* Tn the specimen figured the antenna was curved upwards,

AMPHIPODA. 29

First maville normal.

Mazillipeds as in I. pacifica, except the inner plates, which are oblong and almost
as wide as the outer.

First gnathopods: First joint widest in the middle; wrist rather shorter than the
hand, which is chelate with short spines on the immovable digit.

Second gnathopods: First joint narrow, oblong, as long as the remaining joints ;
wrist and hand subequal, the latter chelate with long plumose sete on the hind
margin.

First and second pereeopods : First joint strong, widening distally ; second as long
as the fourth ; third rather longer and produced behind.

Third pereopods : First joint oblong, with a median ridge and five subequal teeth
on the hind margin. In young specimens the spines are fewer and less equal. The
side-plates are wider than deep, with a tooth directed backwards.

Fourth pereeopods: First joint rather wider than in the third pair, with fewer
and more unequal teeth, and the posterior angle very acute and upturned.

Lifth pereeopods: Side-plates small. First joint wider than in the fourth pair,
with four unequal teeth on the hind margin, and the posterior angle still more acute
and produced.

First uropods: Rami subequal, shorter’ than the peduncle.

Second uropods : Outer ramus two-thirds of the length of the inner which is rather
shorter than the peduncle.

Third uropods : Rami wide-lanceolate and subequal, longer than the peduncle.

Telson emarginate, the outer angles reaching to the end of the peduncle of the
third uropods.

The nearest ally of this fine species is L. pulchridentata, Stebbing, from Heard
Island, from which it differs in not having the lower ends of the first three pairs of side-
plates forked, and in the numerous dorsal spine-like teeth on the seventh mesosome and
three pleon-seements.

I. tonerprs. (Pl. 9, fig. 17.)
TI. longipes, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 151.

Coulman Island, 100 fm., 13 Jan., 1902; one, length 30 mm. (not dissected).

Mesosome wide; pleon and urus compressed. //ead, exclusive of the rostrum,
longer than the first segment; rostrum fully as long as the rest of the head, detlexed
and pointed ; ocular lobe rounded in front and terminating below in a strong tooth
directed downwards. yes round-oval, dark, widely separated.

First segment considerably longer than the second (which is the shortest of all) and
subequal to the sixth; third, fourth, and fifth shorter than the first and subequal ;
seventh as long as the fifth and sixth united, with two long subdorsal teeth directed
backwards. The first side-plates are rather deeper than the segment, much expanded
below and rounded; second and third bluntly pointed ; fourth sharply pointed below,

30 A. O. WALKER.

with the hind margin produced backwards in a spur; fifth and sixth with the
hinder angles acute ; seventh small and subquadrate.

The first two pleon-segments have two long subdorsal teeth, as in the seventh
seoment ; the lower margin of the first is narrowed, with the posterior angle obtuse ;
the hind margin of the second is concave with the posterior angle acute ; the third
segment is smooth with the posterior epimeral angle forming a short, blunt tooth and
a longer curved tooth above it.

First segment of the wrus dorsally depressed, much longer than the remaining two
united.

Upper antenne: First joint with a strong distal tooth on the inner side reaching
almost to the end of the second joint.

First gnathopods with a chelate hand.

Last three pairs of pereopods increasing in length successively, the last pair
extending much beyond the ends of the uropods; hind margin of the first joints
smooth, more or less concave, and ending below in a subacute tooth.

Telson veaching to the base of the peduncles of the third uropods, shorter than the
width at the base, rather deeply notched.

I. nopesont. (PI. 11, fig. 18.)
T. hodysoni, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 152.

Coulman Island, 13 Jan., 1902, 100 fm., one.

The whole body is clothed with fine spine-like teeth directed backwards and
arranged more or less in zones on the segments of the mesosome, pleon, and urus; the
side-plates are also densely spinous, and appear to be a little deeper than the segments.
The body is but little compressed laterally and is widest about the first and second
segments of the mesosome. The antennee are rather short, subequal, and directed
outwards, the basal joints of the upper being a mass of branching spines. The rostrum
is almost straight and about as long as the rest of the head. yes round, darkish, and
far apart.

Inner plates of the mazillipeds folded and squarely truncate; outer broad and
rounded.

The gnathopods resemble those of J. obesa, Rathke.

Length 20 mm.

The single specimen was only partially dissected.

FAM. EUSIRIDA, G. O. Sars.

EUSIRUS PROPINQUUS.
Eusirus propinquus, G. O. Sars. ;

W.Q., etc., various dates, very abundant.
The only points of difference between this form and the type are as follows: The

AMPHIPODA. 3]

first pair of side-plates are produced in front toa rounded acute angle ; the eyes are
dark brown (in spirit) instead of light red ; the antennee have longer and more slender
flagella, and the telson is less deeply divided. The two last characters, however, vary
with age ; thus the telson in an adult female is like that of FE. minutus as figured by
Sars, while in an immature specimen it resembles that of /. cuspidatus, Kr.

Tn the large number of specimens taken but few are adult, viz. :—

1 male, length 50 mm., W.Q., 25 April, 1903, Hole 8, 10 fm.

1 female, with young, length 48 mm, W.Q., 25 Mar., 1903, Hole 8, 10 fm.
1 female, with ova, length 48 mm., W.Q., 31 Mar., 1903, Hole 4, 6 fm.

1 female, with ova, length 48 mm., W.Q., May, 1903, Hole 8, 10 fm.

In all probability this species, like our own Gamimarellus (Amathilla) homari, Fabr.,
inhabits deep water when full grown, only coming to shallow water to deposit its young,
which are hatched in the brood pouch.

Mr. Hodgson writes : “ This species occurred constantly in the traps, but in small
numbers. I therefore soon ceased to preserve specimens, unless | could get them in
good condition, and as their length of leg rendered this difficult, occasional specimens
occur in the collection from most periods of the year. As far as I recollect, the adults
with ova or young were only taken in the summer or autumn.”

HK. microps. (Pl. 11, fig. 19.)
£. microps, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 152.

W.Q., Hole 8, 10 fm., 10 May, 1903, one, length 25 mm., and 1 June, 1903, one,
length 30 mm.; Penguin Rookery, Mount Erebus, Feb., 1904, one, length 48 mm., in
bad condition.

Last segment of the mesosome and first two of the pleon carinate, with a postero-
dorsal tooth. Third pleon segment with the carina rounded behind, hind margin
rather convex, finely crenate in adult, the posterior angle a little produced and acute
with a row of five or six intramarginal spines on the lower margin in front of it.

Urus with the first seoment dorsally depressed.

Side plates small, the first subquadrate, not wider below; the next three sub-
triangular, the apex below ; all rather deeply and irregularly crenate on the lower margin.

Head subequal to the first segment ; ocular lobe not prominent, truncate. Kyes
dark, almost round, diameter less than that of the first joint of the upper antenne.

Upper antennz reaching the base of the uropods ; first joint about three-fourths of
the length of the second, with a distal prominence on the lower margin terminated by
a very sharply pointed tooth with a spine and a few sete behind it; the second joint
expands at the distal end, where there are two or three acute teeth; the third is
subequal to the first of the flagellum. Secondary appendage as long as, and closely
adherent to, the first joint of the flagellum.

VOL, Ill,

oo
bo

A. O. WALKER.

Lower antennze about half as long as the upper, the peduncles being subequal ;
second and third joints subequal.

Mandibles: First and second joints of the palp together longer than the mandible
and four-fifths of the length of the third joint.

First mazxille: Inner plate with five or six sete.

Maxillipeds as in E. longipes, Stebbing.

First gnathopods: First joint robust ; hinder angle of the third joint acute, as well
as the carpal spur, densely setose ; hand much longer than wide.

Second gnathopods rather longer than the first, the front margin of the second
joint produced over the third.

First and second pereeopods very slender, first jomt about six times as long as wide
and subequal to the next two; third joint twice as long as the fourth and rather longer
than the fifth ; all the jomts with a few plumose setze.

Remaining pereopods increasing in length backwards ; the first joint has the hind
margin rather concave, ending below in a sharp tooth, except in the third pair; the
third joint is two-thirds of the length of the fourth, which is about three-fourths of the
fifth ; all the joints spinous and clothed with long plumose setz. Dactylus slightly
curved, the point blunt with a curved tooth near it.

Second uropods : Outer ramus about half as long and wide as the inner; this is a
little longer than the peduncle, subequal in extent to the third uropods and spinous on
both margins.

Third uropods: Rami subequal and similar, lanceolate, rather longer than the
peduncle, with spines and plumose setze on the inner margin.

Telson reaching beyond the end of the peduncle of the third uropods, with a small
notch at the tip, the terminal divisions acute.

Recognisable by the relatively small eyes and slender hirsute legs. From its
nearest ally, H holm, H. J. Hansen (Dijmphna Togtet Krebsdyr, p. 42, Pl. 22), it
differs in the structure of the gnathopods.

FAM. CALLIOPIIDA, G. O. Sars.

ORADAREA LONGIMANA.*
Oradarea longimana, A. O. Walker.

Cape Adare, 9 Jan. 1902, 20 fm., nine young of various sizes, showing the gradual
development of the dorsal teeth. Coulman Island, 13 Jan. 1902, 100 fm., three;
W.Q., 19 Nov. 1902, Hut Point, one, length 20 mm.; 10 Jan. 1903, one; 26 Feb.
1903, one; 16 Mar. 1903, 35 fm., Hole 7, one ; 30 Sept. 1903, Hole 12, one.

* Mr. Stebbing remarks on this species (Tierreich, Amphipoda Gammaridea, p. 727): “ Strangely like Lept-
amphopus novee-zelandie, G. M. Thomson.” It differs, however, from this species as described in Trans. N. Z.

Institute, Vol. II. p. 239, Pherusa nove-zelande, in having only the first two pleon segments dorsally produced

in one tooth, instead of the two posterior segments of the mesosome and two anterior of the pleon produced into
two teeth; also in the upper antenne having an appendage.

AMPHIPODA. 33

In the description of this species I omitted to mention that in both pairs of
antennz the second joint is produced distally on each side of the third joint in a
subacute lobe or tooth.

ATYLOIDES SERRATICAUDA.
Atyloides serraticauda, Stebbing.

Cape Adare, 9 Jan. 1902, 20 fm., one; and 24 Feb. 1904, in Laminaria roots,
13-20 fm., several. Cape Wadsworth, 15 Jan. 1902, 8-15 fms., one.

In addition to the difference noted in the description of the specimens taken by
the ‘ Southern Cross’ expedition at Cape Adare, viz., seven teeth instead of two on the
hind margin of the third pleon segment, the following may also be mentioned :—

1. The eyes are hardly so large and vary much in depth of colour.

2. The first joint of the upper antenne has a strong tooth at the distal end of the
lower margin.

3. The side-plates of the first and second gnathopods have more teeth on the
lower margins—about seven on the first and four * on the second. These, however, may
be considered as merely local or age variations, and are not, in my opinion, sufficient
to constitute a new species. The ‘Challenger’ specimens from “off Melbourne ”
measured { inch or about 6 mm., the largest of the Cape Adare (‘Southern Cross’)
bemg 15 mm.

STEBBINGIA GREGARIA.

Stebbingia gregaria, Pfeffer, Krebse v. Sud-Georgien Die Amphipoden, Jahrbuch d. wissenschaft. Anstalten
Hamburg, V. (1888), p. 110.

W.Q., 29 Aug. 1902, Hole 12, two young specimens, length 6 mm.

These specimens differ in several respects from <Atyloides australis (Miers) as
described by Stebbing (Chall. Rep. p. 914). The basal joints of the flagellum of the
upper antennze are longer than wide, and there is no secondary appendage, both of
which points agree with Pfeffer’s description, but not with Stebbing’s. The outer rami
of the third uropods are shorter than the inner. The telson is divided only one-third of
its length, with the tips of the divisions evenly rounded. In these last two points they
differ from both Stebbing’s and Pfeffer’s descriptions, but the specimens are too young
for any reliance to be placed on them. On the whole they agree better with Pfefter’s
species than Stebbing’s, of the identity of which I am doubtful (see Chall. Rep. pp. 913,
914, and 1654).

PONTOGENEIA MAGELLANICA. (PI. 12, fig. 20.)
Atylopsis magellanica, Stebbing.
Pontoyeneia magellanica, Stebbing.

W.Q., Hut Point, 13 Sept., 1902, one; 23 Nov., 1902, one, length, 12mm. Tent
Island, 3 Jan., 1904, three.

This is a similar instance to the last species of small variations which are insutti-

* In a young specimen there are only two.

34 A. O. WALKER.

cient for the establishment of a new species. The hind margin of the third pleon
segment above the upturned angle is almost straight; the whole lower margins of the
first side-plates are serrate ; the hand of the first gnathopods is considerably longer than
the wrist, in proportion of six to four, and the divisions of the telson are smooth and
rounded at the tips.

FAM. ATYLIDA, G. O. Sars.
ATYLUS WALKERI, Stebbing.

Atylus antarcticus, A. O. Walker.
Atylus walkeri, Stebbing.

W.Q., 31 Jan., 1902, Hut Point, 3 fm., several; 18 Mar., 1902, 10 fm., four;
28 Nov., 1902, one.

Length, 15 mm.

FAM. DEXAMINIDA, Srepsrne.

POLYCHERIA ANTARCTICA.

Dexamine antaretica, Stebbing, Ann. and Mag. Nat. Hist. XV. (1875), p. 184.
Polycheria antarctica, Stebbing.

W.Q., 30 Sept., 1903, Hole 12, D net, six ; length 6 mm.

This species was described by Mr. Stebbing, in 1875, from three small specimens
found in a sponge dredged up by Sir J. Ross a few miles to the E. of the ‘ Discovery’s ’
Winter Quarters. The specimens were not in good condition, or, probably, full-grown,
so that the description is not as satisfactory as it might otherwise have been. Mr.
Stebbing informs me that he has now united his 7riteta Kergueleni with this species.
The present specimens agree with the description of 7. Kergueleni, except in the
following features: the side-plates of the first gnathopods are subquadrate, not
produced in front; the posterior angle of the third pleon segment is produced, and
acute; the margins of the telson are without spines; and the inner plate of the first
maxillee has two sete.

Polycheria tenuipes, Haswell, P. brevicornis, Haswell, and P. obtusa, Thomson,
have been referred to this species. The description and figure of the second gnathopod
of the first of these, and the description of the same limb in the second, are quite unlike
that of P. antarctica (Proc. Linn. Soe. N.S.W., Vol. IV., 1880, pp. 345-6, Pl. XXII,
fig. 8¢.).

MELPHIDIPPA MACRURA.
Melphidippa macrura, G. O. Sars.
Jan. 27, 1902, 300 fm., one; length to end of telson 25 mm.

The specimen which, with the exception of the loss of the third uropods, was in
excellent preservation and was therefore not dissected, agrees with Sars’ description

AMPHITPODA. 35

except that the middle postero-dorsal tooth on the first and second pleon segments is
shorter, a character of little importance.

FAM. LILLJEBORGIUDA, Sressrne.

LILLJEBORGIA DUBIA.
Lilheborgia dubia, Haswell.

W.Q., 29 Aug., 1902, and 28 Nov., 1902, two specimens, both young, the largest
12 mm.

FAM. PHOTIDA, G. O. Sars.
HAPLOCHEIRA BARBIMANA.

Haplocheira barbimana, G. M. Thomson.

Fairly abundant in W.Q., Oct. and Nov., 1902, especially at Hut Point ; also at
Flagon Point, 23 Jan., 1902, and W.Q., 30 Sept., 1903.

The appendage of the upper antennz, which was broken in the ‘Challenger’
specimen, is three-jointed, the first wider than, but subequal in length to, the second :
the third minute, reaching almost to the end of the second joint of the flagellum. The
first urus segment has two small postero-dorsal teeth; these are sometimes difficult to
see, and may have escaped Mr. Stebbine’s notice, as they are not mentioned in his
description. No sexual differences were observed. The females taken (except two on
1 Oct., 1902, which had young in their pouches) had generally parted with their ova.

EURYSTHEUS LONGICORNIS. (PI. 12, fig. 21.)
Gammaropsis longicornis, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 153.

W.Q., 29 Jan., 1902, one female; W.Q., 20 Feb., 1902, several males and females :
W.Q., 19 Mar., 1902, 10 fm., one female ; W.Q., 22 Mar., 1902, 10 fm., one female.

Flead almost as long as the first two segments ; ocular lobe not much produced,
angular.

Eyes round, red in the centre.

Third pleon segment dorsally depressed behind; posterior angle rectangular.
First urus segment dorsally depressed in front. First four side-plates not as deep as
the segments.

Female :—

Upper antennz, reaching to the penultimate joint of the flagellum of the lower ;
the first joint more than twice as thick and less than half as long as the second, which
is about one-fifth longer than the third; flagellum six-jointed, the first joint almost as
long as the next two; appendage one-jointed, about one-third as long as the first
joint of the flagellum.

36 A. O. WALKER.

Lower antenne: First joint stout, about one-third of the second, which is shorter
than the third; flagellum subequal to the second joint of the peduncle, five-jointed.
Both pairs of antenne are sparsely setose.

Mouth organs normal; the mandibular palp reaching beyond the first joints of
the antennse. The outer plates of the maxillipeds have spine-teeth only on the distal
end of the inner margin.

First gnathopods : Side-plates oblong, rounded below, deeper than wide. First
joint narrow, shorter than the fourth and fifth joints united ; wrist subequal in length
and width to the hand, hind margin convex, flattened near the middle; hind margin of
the hand evenly convex, palm spinulose. Dactylus slender.

Second gnathopods : Side-plates as in the first pair. First jomt widening distally ;
wrist subtriangular, half as long as the hand, the hind margin subangular and setose ;
hand with the palm subequal to the rest of the hind margin, minutely crenulate, slightly
convex near the base of the dactylus, then concave to the palmar angle, which is
rounded, with a spine on the side. Dactylus with two or three teeth near the point.

First and second pereopods as in E. erythrophthalmus, but less setose.

Last three pairs of pereeopods increasing in length successively, the third pair as in
G. nana, Sars; the fourth and fifth have the hind margin of the first jot convex
above and almost straight below, with the posterior angle right. The last pair do not
extend beyond the uropods.

First and second uropods: Outer rami shorter than the inner and subequal to the
peduncles.

Third uropods: Peduncle twice as long as the styliform rami, of which the outer is
slightly the shorter. All the uropods are sparsely spinous.

Telson not reaching to the middle of the peduncle of the third uropods, roof-shaped,
with a small notch and spine at the distal end ; when flattened and seen from above it
appears to be triangular.

Length 6 mm.

Male :—

Upper antennz not reaching the end of the peduncle of the lower, otherwise as in
the female.

Lower antenne almost as long as the whole animal.

Second gnathopods: First joimt stouter than in the female, the front margin
terminated by a blunt tooth ; wrist very short, hind margin a little produced, sub-
angular, setose; hand widening distally, front margin almost straight, hind margin
rather longer than the palm, rather convex, with four fascicles of setae terminating in a
strong tooth forming the palmar angle; palm almost transverse, with a strong tooth
behind the palmar one and an irregularly toothed and setose space between it and the
base of the dactylus, the pot of which reaches to the palmar angle, but is carried over
the side of the hand.

Length 6 mm.

AMPHIPODA. 37

The most noticeable character of this species is (as the name implies), the great
length of the lower antennz, especially in the male.

FAM. SEBID. nov.

Body rather slender, subdepressed ; side-plates moderately deep.

Antenne subequal, rather short.

Mandibles with a toothed cutting edge, molar tubercle obscure, palp rather small,
three-jointed.

Mazxillipeds with small inner and outer plates, palp well developed.

First gnathopods chelate in the females, chelate or subchelate in the males.

Second gnathopods longer than the first, perfectly chelate.

Third uropods uniramous.

Telson entire.

The genus Seba has been successively allotted to “the confines of the family
Leucothoide (G. O. Sars),” Stebbing, p. 783; the Lysianasside, Della Valle, p. 773* ;
and the Corophidex, Chevreux,f p. 111. As none of these positions is satisfactory, |
have thought it better to establish a new family for it. As for the genus, it appears to
me extremely doubtful whether the original species (S. znominata, A. Costa, of Sp.
Bate, Brit. Mus. Cat., p. 159), as described by him, ever existed ; it was repudiated by
A. Costa. I propose, therefore, to call it Seba, Stebbing, 1875, with Seba saundersi,

Stebbing, as the type.

Sepa anTarctica. (PI. 13, fig. 22.)
Seba antarctica, A. O. Walker, Ann. and Mag. Nat. Hist. XVIII. (1906), p. 154.

Common in sponges at Hut Point.

The females of this species agree in the smallest detail with the very careful and
accurate description of Seba saundersi, Stebbing, in the * Challenger’ Report, and I have
very little doubt that it is identical. For reasons given elsewhere, however, it is
impossible, in the absence of the description of the male from the same locality as
S. saundersi (off Cape Virgins, Patagonia), to be certain of this.

For the description of the female I refer to that of S. saunders: above mentioned.
The males appear to be dimorphic; the commoner form is only to be distinguished
by the absence of the incubatory lamellz. In one gathering, however (W.Q., 19 Mar.,
1902, 10 fm.), two male specimens, measuring respectively 7 mm. and 5 mm., occurred ;
the length of females with ova and small males being 4°25 mm. In addition to their
larger size, these were remarkable for having the meral joints of the last three pairs of
perseopods greatly expanded behind, especially in the larger of the two.

* Fauna and Flora d. Golfes v. Neapel. Gammarini, p. 773.

+ Amphipodes provenant des Campagnes de I’Hirondelle (1900), p. 111.
$~ Ann. and Mag. Nat. Hist. XVII. (1906), p. 569.

38 A. O. WALKER.

FAM. ISCHYROCERID.E, Sressine.
Hemisassa.

Since the publication of Jassa goniamera, A. O. W., Canon A. M. Norman has
pointed* out that the genus Jussa, Leach, was restricted by Bruzeliusf to species with
the upper antenne “flagello appendiculari destitute,” or, as is the case with his type
species J. capillata (Rathke), having only a rudimentary appendage. As J. goniamera
has a well-developed appendage, but differs from /schyrocerus, Lill}. and Bruzeliella,
Norman, in having no secondary teeth on the outer ramus of the third uropods, it
becomes necessary to establish a new genus.

HeMIJASSA GONIAMERA.

Jassa goniamera, A. O. Walker.

Coulman Island, 100 fm., 13 Jan., 1902, two specimens; W.Q., Flagon Point,
10-20 fm., 17 Jan., 1903, three ; and 23 Jan., 1903, two.

FAM. COLOMASTIGIDA, Srepsine.
COLOMASTIX PUSILLA.
Colomastix pusilla, Grube, Ausflug n. Triest, p. 187 (1861).

Oct. 1902, Hut Point, D net; sponges. Two males, one young, length 4°5 mm.
Differs from C. brazieri, Haswell, in having the first two pairs of pereeopods
subequal and similar to the remainder ; also in the shape of the telson.

* Ann. and Mag. Nat. Hist. XVI. (1905), p. 83, note.
+ Bidrag till Kinn, Skand. Amphipodens Fauna, 1858,

EXPLANATION

OF PLATES.

LIST OF ABBREVIATIONS USED WITH THE FIGURES.

¢ = cephalon, head.

ant?, ant? = upper and lower antenn.
M = mandible.

Mp = mandibular palp.

mex, mz? = Ist and 2nd maxillx.

map = maxillipeds.

Fig.

1.—Hyperia macronye.

. 4.—Waldeckia obesa, Chevreux.

. 5.—Aristias antarcticus.

. 3.—Hyperiopsis australis.

. 8.—Podoprionides incerta.

. 10.—Proboliella typica.

. 11.—Thaumatelson herdmani.

. 13.—Epimeria inermis.

. 15.—Epimeriella macronyz.

. 16.—Iphimedia echinata.

. 18.—Iphimedia hodgsoni.

- 20.—Pontoyeneia magellanica.

PLATE 1.

PLATE 2.

PLATE

ee

PLATE 4.

PLATE

on

PLATE 6.

PLATE

PLATE

2)

PLATE 9.

PLATE 10.

PLATE 11.

PLATE 12.

PLATE 13.

. 22.—Seba antarctica. The figure of the whole animal is drawn from the larger

ban)

gm, gn* = 1st and 2nd gnathopods.
pp *® = 1st to 5th pairs of pereeopods.
up* = Ist to 38rd pairs of uropods.
T = telson.

pl = pleon; pl? = 3rd pleon segment.
ur = urus and appendages.

Fig. 2.—Hyperoche luetkenides.

Fig. 6.—Orchomene goniops.

Fig. 7.—Orchomenella chelipes.

Fig. 9.—Proboloides antarcticus.

Fig. 12.—Oediceroides calmani.

Fig. 14.— Epimeria macrodonta.

Fig. 17.—Iphimedia longipes.

Fig. 19.—Eusirus microps.

Fig. 21.—Eurystheus longicornis.

of the two males mentioned on p. 37, while pp’ ¢ is from the smaller of the two :
note the difference in the third joint.

VOL, III.

K

Amphipoda Pi i

2

2g \
ey sy
3 \ — ,
ves / —e on
= PX —s) oe x

~ \ Z =i — es a — -
ee Se gp

; Hoth del sc et imp.
HYPERIA MACRONYX. 2: HYPEROGHE LUTKENIDES:

Amphipoda Pl. 2.

: Huth del.sc et imp
4. WALDECKIA OBESA.

nt arctic (Discovery) ‘Exp: : Huth dsl sc et imp
S. ARISTIAS ANTARCTICUS. 6. ORCHOMENE GONIOPS.

om

Ammphipoda Pl. 4.

covery) Exp. ; Huth del sc.et imp
3. HYPERIOPSIS AUSTRALIS. 7. ORCHOMENELLA CHELIPES.

“e

Amphipoda Pls.

Huth del se et mp

very) Exp.
8. PODOPRIONIDES INCERTA. 9. PROBOLOIDES ANTARCTICUS.

Amphipeda Pl. 5.

J LJ
le (Discovery) Exp. , Huth del se et imp.
(0. PROBOLIELLA TYPICA. 12. OEDICEROIDES CALMAN|.

Amphipoda Pi. 7.

covery) Exp. Huth del. sc et imp

11. THAUMATELSON HERDMANI,.

Amohipoda Pl &

etic (Discovery) £ xp.

TA.

EE. MACRODON

14.

13. EPiIMERIA INERMIS.

LE M.

ath

Huth, de] sect imp

ree

5. EPIMERIELLA MACRONYX. 17, 1PHIMEDIA LONGIPES.

Amphipoda PL10.

“Huth, del sc.eb amp

16, IPHIMEDIA ECHINATA.

Amphrpoda Pi 11.

o ; — ;
Mf, Wy) Nr j - . Wy y/ 1é gue
WW hy, “Big”
Wi YF 2, 70
GUY Gy }

C iscover'y) Exp. Huth del. sc et imp.

18. IPHIMEDIA HODGSONI|. 19. EUSIRUS MICROPS.

Amphipoda P1.12.

ic| D iscovery)Exp.
20. PONTOGENEIA MAGELLANICA. 21. EURYSTHEUS LONGICORNIS.

Huth del.sc.et imp.

—

fanuphipoda P1.13.

Huth del, sc, et imp.

CRUSTACEA.

IV-LbEPTOSTRACA.

Von Dr. Jon. THIELE, BERLIN.

ZAHLREICHE Leptostraken hat die ‘ Discovery ’-Expedition erbeutet, sie sind mir zur
Untersuchung tibersandt worden. Es hat sich herausgestellt, dass alle Exemplare
zu einer und derselben Art gehdren, und zwar zu der Form, die ich zuerst aus der
Magellanstrasse erhalten habe, weshalb ich sie Nebalia longicornis imagellanica
benannte (Die Leptostraken. Wissenschaftl. Ergebnisse der Deutschen Tiefsee-
Expedition auf dem Dampfer ‘Valdivia, 1898-1899, v. 8, p. 13, 1904). Die
Unterart magellanica unterscheidet sich von der typischen Nebalia longicornis durch
einen starken, nach vorn gerichteten Sinneshécker tiber dem Auge. Dieselbe Form
hat dann die Deutsche Siidpolar-Expedition in ihrer Winterstation am Gaussberge
gesammelt (Die Deutsche Siidpolar-Expedition 1901-1903, v. 9, Heft 1, 1905) und
dieselbe ist es auch, welche die ‘ Discovery’ mitgebracht hat.

Fic. 2.— Fic. 1.—RostrRvuM, SEEN FROM BELOW.
AUGE.

Zu den Angaben, die ich in den beiden Publikationen iiber unsre Form gemacht
habe, brauche ich nicht viel hinzuzufiigen. Das Rostrum ist ziemlich lang, linger als
ich es sonst bei Nebalia longicornis, die sich durch ein kiirzeres Rostrum von N. bipes
unterscheidet, gefunden habe (fig. 1); das Verhiiltnis der Linge zur Breite ist 2°13: 1.
Der Sinneshécker am Auge ist mehr zugespitzt als gewohnlich (fig. 2), das Auge nimmt
den gréssten Teil des Augenstiels ein. Die vordere Antenne zeigt das typische
Verhalten der Nebalia longicornis, dass am 4° Gliede nur ein Dorn vorhanden ist,
dem sich am Vorderrande 8 Borsten anschliessen.

K 2

Dr. JOH. THIELE.

Nach den 3 Fundorten, von denen Nebalia longicornis magellanica jetzt vorliegt :
Magellanstrasse, Gaussberg und McMurdo-Bai, lasst sich schliessen, dass sie rings
um den Sidpol verbreitet ist.

Durch das Loch Nro. 4 (eine halbe Seemeile von Hut Point, 41 Faden = 75 m.)
wurden zahlreiche Exemplare gefangen, ein einziges durch das Loch Nro. 6 (15 Meile
nordwestl v. Hut Point, 125 Faden = 230 m.).

Chile aC HA.

V.—_OSTRACODA.
By G. Stewarpson Brapy, M.D., LL.D., D.Sc., F.R.S.

(3 Plates.)

In the fifty-seven gatherings submitted to me there occurred only nine species of
Ostracoda. Of these all except two appear to be hitherto undescribed. The paucity
of species is accounted for by the fact that the nettings were made on a very limited
number of small areas, many of them practically identical one with another, and
differing only as to their various dates. The list of species is as follows :—

Conchacia innominata, sp. 0.

Paraconchecia gracilis, Claus.

Pseudoconchecia serrulata, Claus, var. levis, var. nov.

Cypridina glacialis, sp. 0.

Philomedes orbicularis, sp. 0.

Philomedes assimilis, sp. 1.

Philomedes antarctica, sp. 0.

Xestoleberis reniformis, sp. 1.

Linocheles vagans, g. and sp. n.

MYODOCOPA.
CoNCHG@CIA INNOMINATA.
(Plate II., figs. 7-14.)

Shell of the male (fig. 7) seen from the side, subquadrangular, height equal to
about half the length and nearly equal throughout; rostral prominence acutely
pointed, with an underlying sinus of moderate depth; anterior extremity rounded
away below, and forming a curve continuous with the ventral margin, posterior abruptly
truncated, its lower end boldly rounded off; dorsal margin nearly straight or only very
slightly sinuous, obtusely angular at the posterior extremity, ventral rather boldly
and evenly arcuate throughout its whole length.

The capitulum of the frontal tentacle (figs. 8 and 9) is club-shaped, acutely
pointed and slightly hooked at the apex, and in the male bulbously dilated at the base,
its inner margin more or less setose ; stem of the antennule in the male (fig. 8) dilated,

2 G. STEWARDSON BRADY.

almost pyriform ; the proximal long seta armed along its middle third with a double
series of about twenty-five short, sharp prickles (fig. 8); in the female these are
replaced by fine simple hairs (fig. 9). The secondary branch of the male antenna
(fig. 11) bears a large terminal hook, the base of which is sharply bent at a right angle,
and there is the usual fascicle of five long sete ; in the female (fig. 10) the secondary
branch has a simple terminal joint which bears four setee of unequal length. Spines
of the caudal lamine slender and simple (fig. 14). The shell appears simply granular
in structure until after removal of the delicate lining membrane, when it is seen to be
very closely and finely striated in a curvilinear fashion ; there is a conspicuous group
of gland-cells at the postero-ventral angle of the shell, and smaller gland-cells are
continued in single file round the entire margin.

This species occurred plentifully in almost all the nettings taken in Winter
Quarters. It was, indeed, by far the most abundant of all the Ostracoda taken during
the Expedition. It has many points of resemblance to Paraconchecia inermis, Claus,
but cannot be identified with that species.

PARACONCH@CIA GRACILIS.

Paraconchacia gracilis, Claus. Die Gattungen und Arten der Mediterranen und Atlantischen
Halocypriden, p. 15.

Paraconchecia gracilis, Claus. Die Halocypriden des Atlantischen Oceans und Mittelmeeres, p. 66,
Pl. xii.

In a surface gathering from lat. 49° 40'S., long. 172° 18’ 30” E. were found a
few examples of this species. Claus saw only two specimens, a male and a female, in
material taken from a depth of 1500 metres in lat. 37° 45’ N., long. 13° 38’ W.

PSEUDOCONCH@CIA SERRULATA, var. levis.

1874. Conchecia serrulata, Claus. Die Familie der Halocypriden, p. 61, Pl. 1, figs. 2-7, 9-11, PI. ii.
fies. 12, 18, 17, 19.

1880. Halocypris atlantica, Brady. Report on the Ostracoda of the ‘ Challenger’ Expedition, p. 164,
Pl. xi., figs. 1-15, Pl. xii., figs. 11, 12.

1890. Pseudoconchecia serrulata, Claus. Die Gattungen und Arten der Mediterranen und Atlantischen
Halocypriden, p. 20.

1891. Pseudoconchwcia serrulata, Claus. Die Halocypriden des Atlantischen Oceans und Mittelmeeres,
p- 72, Pl. xix., figs. 1-14, Pl. xxiii., figs. 1-13.

1895. Pseudoconchwcia serrulata, Brady. A supplementary report on the Crustaceans of the Group
Myodocopa obtained during the ‘Challenger’ Expedition (Trans. Zool. Soc., London, Vol. XIV.,
Part iii., 1897), p. 96, Pl. xvii., figs. 22-24.

This is a widely distributed species, both in the Atlantic and Pacific Oceans
(Claus). It occurred plentifully in many of the Plankton collections made during the
voyage of the ‘ Challenger,’ but I do not find any distinct record of its occurrence in
higher latitudes than 35° 41’ N. and 56° 54’ 8. It was found in very few of the

OSTRACODA. 3

‘Discovery’ nettings, but in one of these it was plentiful—lat. 56° 54’ S., long.
170° 28’ E. The other stations in which it occurred less abundantly are lat. 49° 40! S,
long. 172° 18' 30” E. (surface) ; lat. 59° 19’S., long. 120° 24’ 30" E. (five fathoms) ;
lat. 58° 49’ 45” S., long. 154° 48’ W. (five fathoms); and in Winter Quarters, No. 8
hole (ten fathoms).

The ‘ Discovery’ specimens differed in all cases from the type in being almost
destitute of colour and striation of the shell, and in the absence of marginal
serrulations, which are usually very distinct. But, apart from these peculiarities, I
cannot find any characters to distinguish them from the type. I propose to give them
the varietal name /ezvis.

CYPRIDINA GLACIALIS.

Shell, seen laterally, ovate, greatest height situated in the middle and equal to
about two-thirds of the length ; anterior extremity rounded off, beak short and acutely

CYPRIDINA GLACIALIS.

pointed, not at all prominent, subjacent sinus small and shallow, posterior extremity
slightly produced below the middle ; dorsal margin boldly and evenly arcuate, ventral
much flattened ; seen from above the outline is elongated, ovate, more than twice as
long as broad, widest in the middle, tapering gradually toward the anterior extremity,
which is subacute, posterior extremity produced and mucronate. Substance of the shell
thin but calcareous, surface smooth, destitute of markings or sculpture, colour yellowish.
Length, 5 mm.

One specimen only—a female
Philomedes assimilis. Winter Quarters, 11th Nov., 1902; Hut Point. Its nearest
allies seem to be Cypridina gracilis, Brady, and, perhaps, C. duteola, Dana, with neither
of which, however, can it be certainly identified.

was seen in a netting consisting mainly of

4 G. STEWARDSON BRADY.

PHILOMEDES ORBICULARIS.

(Plate I., figs. 1-15.)

Shell of the female seen from the side almost circular, except in the region of
the sinus at the ventral margin, length about one-fourth greater than the height
(fig. 1); anterior extremity obtusely angulated above the rostrum, posterior broadly
and evenly rounded, dorsal margin rather boldly arched throughout its whole length,
ventral strongly arched from the deep subrostral sinus backwards. Seen from
above (fig. 2) the outline is broadly ovate, rounded behind and submucronate in
front, greatest width situated in the middle and equal to about two-thirds of the
length. Surface of the shell smooth and densely clothed with a villous coating of
very short hairs; margins of the rostrum and subjacent sinus fringed with stiff
sete (fig. 6). Shell of the male (fig. 8) somewhat elongated, height not greatly
exceeding one-half of the length, rostrum and sinus less developed than in the
female ; posterior extremity obliquely subtruncate, slightly simuated in the middle
and rounded off ventrally ; dorsal margin well arched, ventral forming a continuous
flattened curve. In the young condition (figs. 4, 5), the shell of the female in
lateral view has the postero ventral angle sharply produced and is mucronate when
seen dorsally. The soft parts of the animal have the typical characters of the
genus, but the antennal sete (fig. 8) form two distinct series, the distal set being
about twice as long as the proximal; the secondary branch of the female antenna
(fig. 9) is two-jointed, the basal joint bearing a few short marginal sete, the
second joint four marginal sete, one of which is longer than the rest and plumose,
also a single lash-like apical seta. The secondary branch of the male antenna
(fig. 10) is much like that of P. brenda, but less robust and its marginal sete are
shorter. The principal tooth of the second maxilla (figs. 12, 13) is very large and
strong, somewhat hatchet-shaped, the two extremities produced into strong cutting
lobes, with a third smaller lateral tooth—the appearance of the whole organ,
however, varying very much according to the position in which it is seen. The
other limbs present no features calling for special remark. Length, 2°5 mm.

P. orbicularis was found only in two gatherings (May 23, 1902 and June 15,
1902). It is in all respects very similar to the well-known European species
P. brenda and may perhaps be fairly looked upon as a southern variation of that
form. There is the same characteristic villous covering and the size is nearly the
same, but there is a total absence, in the adult, of any posterior angulations of the
shell, which is also considerably more tumid than that of the northern species.
The rather well marked constriction of the anterior, and the broadly rounded
character of the posterior extremity, when seen dorsally, are also noteworthy features.
The form of the shell in P. brenda seems to be the same throughout life: at any
rate the smallest specimens I have seen present characters exactly the same as those

OSTRACODA. 5

of the adult. But one or two small specimens which occurred along with P.
orbicularis, and which I at first took to be the young of that species, were very
distinctly angulated posteriorly, and I now think that they belong probably to the
following species P. assimilis, especially as they have not the villous covering of
P. orbicularis.

PHILOMEDES ASSIMILIS.
(Plate I., figs. 16-21. Plate II, figs. 1-6.)

Shell of the female seen from the side (Plate II., fig. 1) oblong, subcircular, height
equal to two-thirds of the length, anterior extremity sharply angulated below at its
junction with the wide truncated rostrum, posterior sloping steeply and forming a some-
what rounded, prominent angle at its ventral end; dorsal margin strongly arched,
highest in the middle, ventral evenly but less strongly convex, terminating in front in
a deep subrostral sinus and behind in an obtusely angular process. Seen from above

g. 2) the outline is oblong, ovate, twice as long as broad, greatest width situatec
fig. 2) th tl blone, te, t long as | 1, greatest Ith situated
in the middle, anterior extremity obtusely pointed, posterior produced and mucronate,
lateral margins evenly arcuate. The shell of the male (fig. 3) much longer in
proportion to the height, rostrum and ‘subrostral sinus much less pronounced,
posterior extremity more narrowed and having a larger and more rounded ventral
prominence ; the squamous, marginal lamine of the rostrum are marked with numerous
hair-like striz and are closely punctated (fig. 4). The limbs and appendages do
not present any special specific characters, but the hairs at the base of the claws
of the post-abdomen of the male are more than usually conspicuous (fig. 5).
Length of the female, 1°8mm.

The stations at which P. assimilis was taken were all in Winter Quarters :—

September 30, 1903.—No. 12 hole, D. net 246.
Hut Point.— September 13, 1902, D. net.

Hut Point.—February 13, 1904, D. net 264.
10 Fathoms, March 19, 1902.

November 28, 1902, D. net.

May 23, 1902, and February 13, 1904.

12 Hole, D. net, September 8, 1903.

PHILOMEDES ANTARCTICA,
(Plate III., figs. 1-10.)

Shell of the female seen from the side, broadly subovate (fig. 2), with a prominent
beak, a deep subrostral sinus, and an obtusely prominent postero-ventral angle, greatest
height situated in the middle, and equal to about two-thirds of the length ; anterior
extremity rather narrower than the posterior, sloping steeply from the dorsum to form
the angularly prominent beak; posterior subtruncate, slightly sinuated, rounded off
dorsally, but terminated ventrally by a rounded, backwardly produced prominence ;

VCL, III. L

6 G. STEWARDSON BRADY.

dorsal margin boldly and evenly rounded, ventral evenly convex but not so
fully arched as the dorsal margin. Seen from above (fig. 3) the outline is ovate,
searcely twice as long as broad, widest in the middle, rounded off in front, strongly
mucronate behind. The ventral border of the rostrum is produced into a thin lamina
which is partly overlaid by long closely-set hairs, and the posterior border of the
subrostral sinus is similarly fringed (fig. 4). Shell-surface closely and very finely
punctated throughout, smooth, except on the ventral aspect, where it bears numerous
seattered hairs. Just behind the rostral sinus there isa small patch of eleven or twelve
subparallel strize, and a short series of stiff hairs just within the ventral margin: a
large black eye-spot just within the dorsal border at its anterior third.

The shell of the male (fig. 1) is larger and more elongated than that of the female,
nearly twice as long as broad, with a less pronounced rostral sinus and a much narrower
and more produced posterior extremity, the eye-spot small and situated near the
centre.

Length of the male, 2°3 mm. ; of the female, 1*7 mm.

The setee of the terminal fascicle of the antennule in the female are very short-—
not more than half the leneth of the limb; the second (or third ?) seta of the antennee
is spinulose (fig. 8) in the female, the remaining sete are simply ringed : the secondary
branch of the antenna (fig. 6) is of the usual form, but has an indistinctly jomted
appearance at the apex. Principal tooth of the second maxilla (female) (fig. 9) sharp
and broadly triangular ; ungues of the caudal lamina (fig. 10) rather strongly pectinate
in the female—but only faintly ciliated in the male. The eyes of the male (fig. 5) are
pyriform, and deeply pigmented, the frontal tentacle rigid, dilated, and slightly pig-
mented at the base. Secondary branch of the antenna of the male large and strongly
prehensile (fig. 7), the last joint bulbously dilated at the apex, basal joint bearing a
strongly uncinate process. P. antarctica was found rather sparingly in four of the
gatherings taken at “ No. 4 hole” in a depth of five fathoms.

The shell was in all cases of a thin, membranaceous character, but I suspect that
this may have arisen from the solvent action of the formalin preservative on the

mineral matter.

POD OGOPIA:
XESTOLEBERIS RENIFORMIS.

(Plate I., figs. 4, 5.)

Shell of the male seen from the side (fig. 4) subreniform, much narrower in front
than behind, greatest height situated behind the middle and equal to half the length ;
anterior extremity well rounded, narrow, posterior much wider, not very fully rounded,
dorsal margin forming a continuous arch, highest behind the middle, sloping very
oradually backwards and with a rather steep curve towards the front, ventral margin
rather deeply sinuated in the middle. Seen from above, the outline is broadly ovate

OSTRACODA, 7

(fig. 5), pomted in front, broadly rounded behind, the lateral margins very boldly
arcuate, greatest width situated behind the middle and equal to two-thirds of the
length. The surface of the shell is smooth, deep ochreous yellow in colour, with a
conspicuous dark eye-spot within the dorsal margin near the front, just below and
behind which there is a large irregularly shaped pellucid, sub-circular patch, and below
this again a series of four oblong muscle spots, arranged in a transverse curve, and
in front of these two smaller spots the long diameters of which lie in the opposite
direction. The left valve is the larger of the two, overlapping the right both in front
and behind. Length 0°65 mm. ‘The shell of the female is somewhat more tumid
and seen from the side has no ventral sinuosity ; it is also almost free from anterior

3

depression, the two extremities being nearly equal in width.

Two specimens only of this small species were seen, a male and a female; the
female, however, was only an empty shell and was quite colourless. The exact locality
of the capture I do not know. The specimens were accidentally discovered in a
flocculent diatomaceous deposit which settled from the liquid in which the larger
Cypridinidz had been preserved. The flexuous lateral contour of the male distinguishes
this from any other species of Xestoleberis known to me.

LINOCHELES.*

Differing from the typical Cytheridz in the greatly elongated and thread-like legs
of the third pair, and in the abnormally formed copulatory plate of the male.

LINOCHELES VAGANS.

(Plate III, figs. 11-18.)

co

Shell closely similar in shape to Nesfoleberis; seen laterally (fig. 11) that of the
male is subreniform, greatest height situated behind the middle and equal to much
more than half the length; anterior extremity narrow and obliquely rounded, posterior
very wide and evenly rounded, dorsal margin boldly arched, steeply curved posteriorly,
sloping with a gentle curve to the front, ventral margin sinuated in front of the
middle; seen from above, the outline is elongated, ovate. widest in the middle
(fig. 12), width rather less than half the length, narrowed and obtusely pointed in
front, broader and rounded off behind. Shell-surface perfectly smooth ; colour brown.
Length, 0°64 mm.

Antennules six-jointed, very sparingly setiferous (fig. 13); antenne short and
stout, with short apical claws and a stout urticating seta which reaches to the apices of
the claws (fig. 14). First and second pairs of legs (figs. 15, 16) armed with short and
stout terminal claws; third pair much elongated (fig. 17), the last joint extremely
slender and much longer than the united lengths of the two preceding joints ; terminal

* Xwor, a thread ; x7An, a claw,

8 G. STEWARDSON BRADY.

claw very long, thread-like in its tenuity, nearly half as long as the entire limb ;
external copulative organ (fig. 18) elongated, divided into two portions, the distal part
pear-shaped and attached by a narrow neck to the basal region.

Of this curious form only four specimens were found ; all of them males. Three
specimens from a surface netting in Lat. 49° 40'S., Long. 172° 18°30' E., and one
from a netting in five fathoms, Lat. 58° 49°45’ S., Long. 154° 48’ W. It is difficult
to account for the presence at the surface of an animal quite destitute of swimming
organs. I am disposed to think that the real habitat is probably among floating weeds,
and that the extremely long hinder limb may be useful in giving a grasp of delicate
algve or other vegetation.

EXPLANATION OF PLATES.

PLATE I.
PHILOMEDES ORBICULARIS.

Shell of female seen from left side x 22.

5 ss from above x 22.

, male seen from right side x 30.
6. Beak and sinus of female seen from side x 84.
7. Extremity of antennule of male x 84.

8. Antenna of female x 50.

. 9. Secondary branch of the same x 120.
a LO: ) of male x 120.

11. Mandibular foot of female x 100.

(a) Process of basal joint x 300.

. 12. Principal tooth of second maxilla seen from side x 240.
fo lB rs +s , seen from front x 240.

14. End of vermiform foot x 84.

15. Post abdominal lamina x 84.

XESTOLEBERIS RENIFORMIS.

Fig. 4. Shell of male seen from left side x 84.
a Ok r in from above X 84.

PHILOMEDES ASSIMILIS.

Fig. 16. End of antennule of male x 84.
17. External branch of the antenna of male x 50.
, 18. Antenna of female x 84. :
19. Mandibular foot of female x 100.
(a) One of the marginal setze more highly magnified.
Figs. 20, 21. Principal tooth of second maxilla seen laterally and obliquely x 240.

PIA Byenlile
PHILOMEDES ASSIMILIS.

Fig. 1. Shell of female seen from left side x 40.
a » seen from above x 40.
. » Male seen from left side x 40.
4. Beak and sinus of male x 84.
, }. Post-abdominal lamina of male x 84.

ae 4Oe ra . female x 84.

OSTRACODA. 8

CONCHGICIA INNOMINATA.

Fig. 7. Shell of male seen from left side x 22.
» 8. Antennule and frontal tentacle of male x 84.

” 9. vy ” ” female x 84.
» 10. Internal branch of antenna of female x 84.
oo ile ” ” 9 male x 84.

+ 12. Chewing process of mandible x 240,
» 13. Copulatory organ of male x 84.
» 14. Post-abdominal lamina x 84.

PLATE III.
PHILOMEDES ANTARCTICA.

1. Shell of male seen from left side x 30.
2 » female seen from right side « 30.
3 a5 es » above x 30.
4. Margin of shell of female with subrostral sinus x 84.
+ 5. Hyes and frontal tentacle of male x 55.
6. Secondary branch of antenna of female x 100.
i 35 5 ‘5 male X 100.
8. Portion of second seta of antenna of female with marginal spines x 320,
9. Tooth of second maxilla of female x 84.
0, Caudal lamina of female x 84.

LINOCHELES VAGANS ¢.

Fig. 11. Outline of shell seen from left side x 84.
alee a x 3 above x 84.
» 13. Antennule x 240.
» 14. Antenna (apical joints) x 240.
4 15. Foot of first pair x 240.
eG: » Second pair x 240.
oo oleh » third pair x 240,
» 18. Copulatory organ x 240.

j
2
7

Ostracoda pl. 1.

WA

——

\

+

Cambridge.

G.S.B.del. E. Wilson,

Ostracoda pls.

CRUSTACEA.
VI.-CIRRHIPEDES.

Par A. GRUVEL,

Maitre de Conférences de Zoologie (Université de Bordeaux).

(1 Plate.)

Lxs Cirrhipédes du ‘Discovery’ qui m’avaient été envoyés des le mois de Décembre,
1904, par le “ British Museum,” n’ont pu étre étudiés qu’en Avril, 1906, a cause de
travaux tres importants et tout-a-fait différents que nous avions alors entrepris, en
particulier de nos deux Missions pour l’étude des Pécheries de la céte occidentale
d Afrique.

Bien que peu considérable par le nombre, cette collection du ‘ Discovery ° contient
une espece d’Operculés intéressante, c'est un Elminius rugosus de Hutton, et deux
especes de Scalpellum, nouvelles pour la science : Sv. Discovery: et Se. Bouvier’.

Voici, du reste, la liste de ces especes.

OPERCULATA.

HEXAMERID&.
Genre Balanus, Da Costa.
Une seule espece, représentée par des échantillons secs, dont les pices operculaires
ont entiérement disparu, mais qui est certainement le Pal. psittacus, Molina. Un
individu d’assez grande taille est surtout bien caractérisé.

TETRAMERID®.

Genre E/minius, Leach.

Ce genre est représenté par une seule espece également. Bien que Hutton n’aie
pas publié de figure pour Llminius rugosus, la diagnose assez complete qwil en a donné
se rapporte si exactement a celle de l’espece que nous avons eu a examiner que nous
whésitons pas A Videntifier. Jusqu’ici cette espece n/a été signalée qu’en Nouvelle-
Zélande, sur les rochers du Bluff, par son auteur.

Nous croyons, donc, intéressant de donner quelques figures (fig. 1-3) se rapportant

pS \ r ‘ one . Ay ry eee 4 Cae : abeee
A cette espece récente, trds voisine, comme le dit Hutton, de l Elminius plicatus de Gray.

* Trans. N. Zealand Inst., xi., 1878, p. 328.

2 A. GRUVEL.

PEDUNCULATA.
POLYASPID2.

Les deux espices qui représentent cette famille appartiennent au genre Scalpelluwm
Leach, et sont, toutes les deux, nouvelles pour la science.

Nous avons eu plaisir 4 dédier Tune delles & M. le Professeur Bouvier, du
Muséum de Paris, dont extreme obligeance & notre égard ne s’est jamais lassée, et qui
a bien voulu présenter au public scientifique notre “‘ Monographie des Cirrhipédes.”

Quant & l'autre, nous lui donnons le nom du navire qui a servi a la belle
Expédition scientifique que l’on connait.

ScALPELLUM DISCOVERYI (fig. 4-6).

Diagnose.—Capitulum avec 14 plaques, toutes imparfaitement calcifiées et trés
serrées les unes contre les autres. Carene régulitrement courbe, parfois redressée assez
fortement avec lumbo a l’'apex et le bord dorsal régulierement arrondi. Terga légére-
ment recourbés en arriere, avec le bord occluseur courbe. Rostre bien développé,
triangulaire, avec les bords latéraux & peine recouverts par les bords occluseurs des
rostro-latérales. Infra-latérales avec l'apex situé vers le milieu de la plaque, légerement
rétrécie en ce point. Pas de sous-rostre. Pas de sous-caréne.

Pédoncule tres développé, allant en se rétrécissant, régulitrement, de la région
capitulaire & la base, recouvert d’écailles allongées transversalement, disposées en séries
paralléles et obliques avant en arriére et de haut en bas. Ces écailles sont, du reste,
régulitrement disposées et non imbriquées.

Limite entre le capitulum et le pédoncule, trés nette.

Pas de pénis. Pas d’appendices terminaux ou filamenteux.

Dimensions: Longueur du capitulum : 9™; largeur, 5”.

x pédoncule: 14"; largeur, moy. 2™ 9.

Afjinités.—Par la présence de 14 plaques imparfaitement calcifiées et d’un rostre
trianculaire, cette espbce vient se placer nettement & c6té de Scalpellum intermedium,
Auriv.

Observations.— Dans les deux échantillons appartenant 4 cette forme et que contient
la collection du ‘ Discovery, la calcification des plaques est assez variable. Les deux
figures que nous en donnons (figs. 4 et 5) suffiraient & elles seules & montrer les
différences, parfois consideérables, surtout dans les scuta et les terga.

En effet, tandis que dans le premier type (le plus caleifié, fig. 4), le bord basal
des terga est droit, dans le second, il forme une concavité trés accentuée. I] en est un
peu de méme pour le bord latéral des seuta. Dans le second exemplaire, les plaques
caréno-latérales sont beaucoup plus allongées et plus irréguliéres de forme que dans le

premier.

CIRRHIPEDES. 3

Du reste, dans l'ensemble, le premier individu présente un capitulum moins long
et plus large que le second.

Le pédoncule offre les mémes caractéres dans les deux cas, mais il est plus court dans
le second échantillon, et, comme le capitulum est plus long, il en résulte que la longueur
totale est, trés sensiblement, la méme.

SCALPELLUM BOUVIERI (figs. 7-9).

Dragnose.—Capitulum avec 14 plaques entitrement calcifiées et, le plus souvent,
serrées les unes contre les autres. Umbo de la carne tres net et situé A une petite
distance de l’apex. Bord dorsal de la carene aplati, sans artes latérales. Apex des
terga légerement recourbé en arriére, comme leur bord occluseur. Umbo des caréno-
latérales situé vers le tiers de la hauteur, & partir de la base, et tres légerement saillant
en arritre. Umbo des infra-latérales situé vers le milieu de la hauteur de la plaque, qui
est légerement rétrécie en ce point. Bord occluseur des rostro-latérales d’une longueur
égale environ au tiers de celle du bord latéral, avee l umbo légérement saillant en avant.

Rostre trapézoide, avec une caréne médiane nette et les bords latéraux parfois en
grande partie recouverts par les rostro-latérales.

Toutes les plaques capitulaires sont recouvertes par une cuticule transparente et
glabre, partout tres mince, sauf sur le bord occluseur des scuta et sur tout le bord dorsal
des terga et de la caréne.

Pédoncule de longueur & peu pres égale & celle du capitulum, orné d’écailles
allongées transversalement, en séries paralléles et & peu pres réguliéres, rapprochées
vers le capitulum et s’éloignant de plus en plus du c6té de la base, mais jamais
imbriquées.

Pas de pénis. Appendices filamenteux uniarticulés, 4 peine plus longs que le
protopodite de la sixiéme paire de cirrhes et ornés de quelques rare soles.

Afinités.—Par son aspect extérieur d’ensemble et si on ne la considérait qu'un peu
superficiellement, cette espce pourrait étre assez facilement confondue avec le Scalpellum
angustum de Prof. G. O. Sars. Mais, examinée avec soin, on voit quelle s’en distingue par
plusieurs caractéres, dont les deux principaux sont: la présence d’un umbo tres net & la
caréne qui manque chez Se. angustum, oti cette piece est réguliérement courbe, et enfin
par la présence d’une cuticule chitineuse qui, tres mince dans cette dernitre espéce,
est beaucoup plus épaisse chez la ndtre, spécialement sur les terga et la caréne.

Par la présence de l’umbo situé prés de l’apex de la carene, et par l'ensemble de ses
caracteres, cette espece vient nettement se placer & cété de Se. aduncum, Auriv.

Observations.—Le Scalpellum bouvieri doit étre tres commun dans une partie des
régions explorées par le ‘Discovery,’ car il a été retrouvé dans un grand nombre de
dragages, en quantités trés variables, du reste. Tous les individus que nous avons eu a
examiner sont & peu pres identiques & la forme moyenne que nous avons prise comme
type. Presque tous sont fixés sur des Hydroides de diverses especes et, parfois, en assez
grand nombre, sur une méme toufte.

VOL, III. M

A. GRUVEL.

EXPLICATION DE LA PLANCHE.

Fig. 1.—Scutum @’Elminius rugosus, Hutton, vu du cote interne.
., 2.—Tergum du méme—face interne.
.. 3.—Scutum et tergum du méme, encore unis.
. 4—Scalpellum Discoveryi, n. sp., 1°° forme, la mieux calcifiée.
.. 5.—Autre individu, moins calcifié, de la méme espece.
.. 6.—Rostre et bords occluseurs des rostro-latérales. ;
» 7.—Scalpellum Bouvieri, n. sp., vu du cote droit. ;
.. 8.—Le méme, vu de profil et du cété ventral. :
. 9. Rostre et bords occluseurs des rostro-latérales. : :

N.B.—Dans toutes les figures G = 5.

Antarctic (Discovery ) Exp. Cirripedia

A.Gruvel,ad nat. del A. Benard lith

Figd a3. Elmmius rugosus, Hutton._ Fig. 426 Sealp ellum discovery1,A.G._ Fig 7a9. Sc. Bouvieri,A.G

Imp L. Lafontaine, Paris

PYCeuIN OG ON LD A.
By T. V. Hopeson, F.L.S.

(10 Plates.)

TaE collection of Pycnogonids brought from the Antarctic by the ‘Discovery’ is a
large one, including as it does no less than twenty-eight species, three of which have
been assigned to as many new genera. Only one species can be regarded as of morpho-
logical importance, Pentanymphon antarcticum, which is now known to be abundant
and to have a circumpolar distribution. It differs from the genus Nyimphon only in
the possession of an additional pair of legs. At first this was thought to be quite a
novel feature in the morphology of the Pyenogonida, but the Scotch expedition brought
another and much finer species from the South Orkneys. This proved to be identical
with Decolopoda australis, described by Eights some seventy years ago, and taken at
the South Shetlands. Eights’ work was lost for a long time, and though it has been
noticed recently by modern zoologists, the reception afforded it was extremely curious,
involving as it did the point-blank refusal to accept the possibility of the existence of
a Pycnogonid with more than the orthodox four pairs of legs. Mr. L. J. Cole (7), who
apparently looked with more sympathy on the work of a fellow-countryman, was the
first to appreciate this discovery properly. The genus Lewonymphon was defined by
Professor Mébius for a large but immature specimen taken by the ‘ Valdivia’ in the
vicinity of Bouvet Island. It has been found necessary to re-cast this genus; as now
defined it contains no less than eight species, including two which had been assigned
to the genus Ammothea, and another which Professor Mobius thought should be placed
in the genus Colossendeis. No less than five species were taken by the ‘ Discovery,’
and four of them are new. No true member of the genus Amimothea was seen, but two
new species assigned to new genera, Austrodecus and Austroraptus, belong, as does the
genus Leionymphon, to the family Ammotheide as defined by Professor G. O. Sars.

Austrodecus is perhaps a close relation of Tunystylum, Miers, and is a curious little
form with a slender and elongated proboscis, like the snout of a weevil beetle, no chelifori,
six jointed palps, and small ovigers. Austroraptus is remarkable for its spurred body
and the length of its legs.

Rhynchothorax australis is another curious form; the only other species of the
genus is found in the Mediterranean, but, notwithstanding certain differences, there
does not seem to be any justification for giving the ‘Discovery’ species other than
specific rank.

M 2

bo

T. V. HODGSON.

The remainder of the collection falls into well-known genera, and does not call for
any special comment. A list is appended below of all the species now known from the
Antarctic and sub-Antarctic regions, those taken by the ‘ Discovery’ being marked with
an asterisk. The numerous islands scattered about the southern seas have long been
considered to pertain to the sub-Antarctic region, and for this reason I have made the
mean annual isotherm of 45° F., as indicated by Sir John Murray in the concluding
volume of the “Challenger Reports,” its northern limit. This includes all that can
reasonably be considered as belonging to this region, and coincides very closely with
the opinion expressed by Professor P. Pelseneer in his Report on the Mollusca of the
‘Belgica’ Expedition. For the Antarctic proper the latitude 60° S. seems sutlicient
as it includes all the glaciated lands of Antarctica, and the shallower waters less than
1000fm., connected therewith.

Antarctic. Sub-Antarctic.

Pycnogonum magellanicum, Hoek . ; ; : 5 ; x
% magunirostre, Mébius . : : ; : : <
* Phoxichilus australis. : : j F : : : x
Pallene dimorpha, Hoek ; : : : : : : x
* Pseudopallene cornigera, Mébius . . : ; ‘ : x x
. R australis ; : 3 : : : : x
Pallenopsis patagonica, Hoek. : ‘ : : ‘ : x
k 33 pilosa, Hoek : : : ‘ , : : x x
3 fluminensis, Kroyer x
* 5 glabra, Mobius. 3 ; : : : ‘ x x
* villosa x
: hiemalis. : : : 5 : : ‘ x
Anoplodactylus neglectus, Hoek x
93 petiolatus, Kroyer Ss
Nymphon gracile, Leach x
- gracilipes, Miers x
35 brachyrhynchum, Hoek x
hamatum, Hoek x
fuscum, Hoek x

meridionale, Hoek .
antarcticum, Pfeffer
5 hiemale
lanare .
- adareanum
» frigidum : : : :
Cheetonymphon brevicaudatum, Miers. < : : : x
villosum
biarticulatum
cF mendosum
5 australe, Hodgson
- A var. austrinorum
* Pentanymphon antarcticum j ‘ ‘ : ‘
Leionymphon striatum, Mébius 5 ‘ : : ; x
i grande, Pfeffer :
gibbosum, Mobius. 3 : : a Caer x
% Ininus. : : : : . 4 : x

x
x

Xe EOS xX X XK X

x
x

PYCNOGONIDA. 3

Antarctic. Sub-Antarctic.

Leionymphon clausii, Pfeffer. : : ; : : ; x
* s australe x
43 glaciale . : , , : : : : x
“5 spinosum : : x
Ammothea hoeki, Pfeffer 5 : : : : ; . x
43 wilsoni, Schimkewitsch ; : ‘ ‘ ‘ x
aA communis, Bouvier : F ; : : : x
cs curculio, Bouvier : ; ; : : : x
Tanystylum styligerum, Miers : j : : : ; x
* dohrnii, Pfeffer . : ; . : ; . x
- chierchi, Schimkewitsch — . : ; , . x
* Austrodecus glaciale x
* Austroraptus polaris —. ; : : : ; : ; x
Ascorhynchus glaber, Hoek . : : ‘ ; : ; x
* Rhynchothorax australis ; : ; ‘ : : : x
Colossendeis gigas, Hoek : ; : : 2 ; ‘ x
% leptorhynchus, Hoek
9 gigas leptorhynchus, Hoek x
x megalonyx, Hoek ; : : : ; x
: robusta, Hoek x
» gracilis, Hoek x
- 5 australis x
* 33 elacialis x
a frigida 2 x
, 5 rugosa : ; F , F x
Decolopodaf australis, Eights : ; ; x
3 antarctica, Bouvier x

No less than seven expeditions have taken part in the recent “Siege of the
South Pole,” and the collections of Pyenogonids made by four of them still remain
unpublished. This being the case, it is scarcely desirable to enter into a discussion
on the geographical distribution of these animals. It may, however, be stated that
the head-quarters of these animals appears to be in southern seas. Professor Mobius
(22) has compiled a list of the known Arctic and sub-Arctic species, which
number forty-two. In the same work, for comparison, he has added a list of all
the species taken beyond 30° South latitude. Only thirty-one species are included
in this large area, and the genus Zunystylwm is the only one occurring in the south
which does not occur in the north. I have reduced the Southern or Antarctic area
to what I consider more reasonable dimensions, and the ‘ Discovery’ collection, with
its predecessors, raises the total to sixty-three species. Among these species tliere are
five new genera ; four of these are, as far as is yet known, confined exclusively to
the Antarctic region, the other extends well into the sub-Antarctic region. The
“ Bipolarity Theory” is only affected by a single species, Colossendeis australis. Of
all the numerous species of this genus, C. proboscidea, from the north, and C. australis,
from the south, stand apart from all the rest on account of their bodily form, and
there can be no question that they are much more nearly related to each other than

+ [As Hights said his species had “ five perfect pairs” of legs he doubtless meant to write Decaholopoda.—Ep.

4 T. V. HODGSON.

to any other members of the genus. The two species, as species are recognised
now-a-days, are perfectly distinct, but it is a fair question to ask how is their
present position at the opposite ends of the earth to be accounted for ?

As to the terms employed in the followimg work, some words of explanation
are necessary.

Naturalists have not always used the same terminology, and Mr. L. J. Cole (6)
has recently tabulated the essential variations. As, however, the terms used by
any one naturalist have not been fully adopted, and others have been introduced,
a complete account of the terminology used here is given.

The entire Body of a Pycnogonid is divisible into three regions—the proboscis,
trunk, and abdomen—and this without regard to any of the appendages. Where
the body only is alluded to, it is to be understood that both the trunk and abdomen
are taken together. Measurements are taken dorsally, unless otherwise specified,
except in the case of the appendages, which are generally measured from the side,
and the length of the trunk is usually taken to the base of the abdomen ; in exceptional
cases, where the abdomen is vertical or very short, the trunk may be measured to
the extremity of the posterior lateral processes, but this is so stated. Its width
is always across the longest of the lateral processes.

The Cephalon is regarded as that portion of the trunk which les in front of
the first pair of lateral processes, and the so-called neck is the narrowest part,
sometimes elongated, between those processes and the more expanded distal portion.

Segmentation is not regarded as perfect or complete unless the four segments
of the trunk and the abdomen are distinctly articulated.

The first appendage of the trunk is the Cheliforus, also commonly known as
the mandible. A considerable amount of confusion has been, and is still likely to
be, caused by the fact that the chela has most frequently been regarded as a single
joint. Obviously it consists morphologically of two joints, and in order to avoid any
misapprehension aS to the number of joints, this appendage has been described as
chelate, or otherwise, and the scape, a name given by Professor G. O. Sars to the shaft
supporting the chela, has been recorded as one- or two-jointed, as the case might be.
This method of dealing with the limb is suggested in order to avoid confusion as
to the number of joints it possesses.

The second appendage is the Palp.

The third appendage is the Oviger. This convenient name was given by

ee

Mr. L. J. Cole to replace the more cumbrous term “ ovigerous,” or “ false leg.” — In
these two appendages the various joints are numbered from the base, and not named.
The remaining four or five pairs of appendages are Legs pure and simple ; with
the use of the word “oviger,” the qualification “ambulatory” or “ walking leg”
becomes quite unnecessary. The terms used for the individual joints are those
adopted by Professor G. O. Sars, viz., first, second and third coxa, femur, first and

second tibia, tarsus and propodus.

PYCNOGONIDA. 5

A projection beyond the insertion of the terminal claw, which occurs in some
species, is called the Heel, a term introduced by Mr. L. J. Cole. Two other expressions
have been adopted for purposes of convenience. In very many species, not to say
genera, there occurs a thickening of the skin on the sides of the legs, not infrequently
also on some of the other appendages ; this takes the form of a narrow and conspicuous
line, usually of a reddish colour, and so it has been termed the “lateral line.” The
other feature concerns the sete. At the extremity of most of the joints there is
a fringe of more or less specialised sete, sometimes surrounding the joint, but
frequently more conspicuous on the dorsal or the ventral aspect. This has been termed
the distal fringe, a name which does not appear to be inappropriate.

Precise measurements are invariably necessary with regard to the legs. One
leg is generally considered to be sufficient for this purpose, and as Dr. P. P. C Hoek
adopted the third leg of the right side for this purpose wherever possible, the same
limb has been used here.

PHOXICHILUS.

This genus is readily distinguished by its slender form and the complete absence
of chelifori and palps. The ovigers too only occur in the male, and are seven-jointed.
Among other characters may be mentioned the presence of a “collar” between the
cephalon and the proboscis. This, however, is deficient in the species described below.

Numerous species have been assigned to this genus, but the difficulties of species
discrimination is increased by the absence of two of the normal number of appendages,
and necessitates some modification of the generic characters. No less than six species have
been described from European seas, but their specific distinctness is open to question.
Three others have been found in distant seas, and a fourth now deseribed is from the
extreme south.

PHOXICHILUS AUSTRALIS.
(Plate L., fig. 1.)

Specific characters :—
Body slender, with lateral processes very widely separated and with the long legs completely
covered with very minute stiff sete.
Tarsus with a very prominent ventral spine, and three to five proximally on the propodus,
which projects distinctly beyond the insertion of the terminal claw and auxiliaries.
No distinct collar anteriorly to cephalon.

Body slender, with the lateral processes long and very widely separated ; perfectly
smooth to unassisted vision, but with a l-in. objective extremely minute spines can be
detected ; segmentation very prominent and immediately behind each pair of lateral
processes.

The Cephalon is small, but stouter than the trunk, truncated anteriorly with the
angles bevelled off. No collar exists as such, but a band of thin chitinous skin,
characteristic of an articulation, occurs between the cephalon and the base of the
proboscis.

6 T. V. HODGSON.

The Ocular tubercle hes almost in the middle of the cephalon, but scarcely clear
of the first pair of lateral processes. It is very stout, of no great elevation, terminating
in a strong cone above the four eyes.

The Abdomen is small, cylindrical, terminating in a cone, and directed almost
vertically upwards. It is not articulated to the trunk.

The length of the trunk is 5mm. (to extremity of posterior lateral processes) and
its extreme width is 3mm.

The Proboscis is long and slender, scarcely 4mm. in length, flexibly united to the
trunk. It is cylindrical, but very slightly swollen before the middle and equally
slightly narrowed before its rounded extremity. The mouth is inconspicuous, but of
normal size. The proboscis is covered, more especially distally, with extremely
minute spines.

The Legs are long and slender, attaining a length of 30mm. The first coxa is the
smallest, and the second is a trifle longer than the first and third together ; the pro-
portions of the three following joints are as 8 : 6°75 : 8°5; the tarsus is very small, and
the propodus, which is curved, is about a quarter the length of the femur. The entire
limb, as the trunk, is completely clothed with extremely minute stiff setze, which for
the most part are only visible with a powerful lens. On the tibia they are, however,
rather more conspicuous, besides being most abundant. The larger or ventral surface
of the tarsus is covered with short spines, but one distal one is extremely large and
prominent. Dorsally the propodus is covered with the minute stiff setae, ventrally there
are at the proximal end of the joint three to five very large spines, the remainder of
that surface bemg occupied by a band of much smaller though still conspicuous
spines of rather irregular size. A prominent heel projects over the insertion of a
powerful terminal claw and its two auxiliaries, these latter bemg about half its length,
but much more slender. The second coxa bears dorsally, just beyond the middle of its
length, a tubercular enlargement, which is perforated by a glandular opening.

The genital apertures occur on a transverse ridge at the extremity of the second
coxa of every leg. Ventrally, in the angle formed by the first pair of lateral processes
and the trunk, there is a very small but distinct process on each side, exactly in the
position where the oviger should be.

This type specimen is a female, and was taken off Flagon Point in Winter Quarters
in 5-20 fm., on very rough ground. :

Two other females were taken, one slightly larger than the type came from
125 fm., on a bottom composed of small stones and organic débris; the other is much
smaller, but the precise pomt at which it was captured in Winter Quarters remains
uncertain. A fourth specimen is a male, and is to a considerable extent overgrown
with polyzoa. This specimen was taken at the same time and place as the type. It
is sexually mature, and the genital apertures occur on the three posterior legs only.
The ovigers are well-developed, but unfortunately only four basal joimts remain on
either side. They arise in the angle formed by the first lateral process and the trunk,

PYCNOGONIDA. if
but not on a body process ; the first joint is small, the second is a little longer, the two
following which are longer still, the fourth is largest. The appendage bears a moderate
number of minute setze.

I have been unable to distinguish the cement glands on the femur as described
and figured by Professor G. H. Carpenter for other species. (4 and 5.)

PSEUDOPALLENE.

This genus, established by Mr. E. B. Wilson in 1878, has been more completely
defined in accordance with modern requirements by Professor G. O. Sars (25). It is
very closely allied to Cordylochele (G. O. Sars), but the special features which
distinguish it from that genus are (a) the crown of sete at the distal extremity of the
proboscis ; (6) the presence of spines on the body and legs.

Two species are now described, one of which I regard for the present as identical
with those derived from the ‘ Valdivia’ and ‘ Frangais’ Expeditions.

PSEUDOPALLENE CORNIGERA.

(Plate I., fig. 3.)
Pseudopallene cornigera, Mobius (23). p. 186.
Cordylochele turqueti (?), Bouvier (2). p. 297.

Specific characters :—
Body with long lateral processes not very widely separated, these armed dorsally with a stout

spur. A pair of similar spurs on the cephalon.
Legs with longitudinal rows of setie set in small tubercular bases. Propodus well covered with

setze and a proximal group ventrally of half-a-dozen spines.
Oviger ten-jointed. Denticulate spines with three strong teeth at the base.

Body rather robust, with long lateral processes not very widely separated. The
length of these processes is increased by a very prominent spur which occurs dorsally
on each.

A very conspicuous spur occurs on the antero-lateral border of the Cephalon.
This is rather long, with a definitely constricted neck, and widens considerably into two
lobes bearing the chelifori, and between which the proboscis arises.

The Ocular tubercle is short and stout, rounded above, and bears four well-
developed eyes. It lies between the first pair of lateral processes and the neck.

The Abdomen is of normal proportions, gently tapering, and not articulated to the
trunk. It is directed upwards, but does not extend beyond the posterior lateral
processes, and bears a few minute sete. The segmentation is distinct.

The length of the body is 6mm., and its extreme width is barely 5mm.

The Proboscis is ventral in origin, rising apparently from a pocket between the
chelifori, directed obliquely downwards. It is a little longer than the cephalic segment
gently tapering to a blunt point, the small triangular mouth being surrounded by a
tuft of small bristles.

VOL, III,

N

co

T. V. HODGSON.

The Chelifori are well-developed; the scape is single-jointed, about two-thirds
the length of the proboscis, enlarged at its distal extremity, and carries a few minute
sete. The chele are massive, curved almost to a right angle near their bases, and
thickly covered with minute sete. The fingers are short and massive, the immovable
one bears two tubercles distally, but the movable one has none.

Palps are not present, but on either side of the cephalon ventrally, and just outside
the chelifori, there is a small mark, an indication of where they should be. The antero-
ventral margin of the cephalon is a slightly curved line.

The Oviger (fig. 3) is ten-jointed, and is built on much the same lines as in the
genus Nymphon. It arises on a very small body-process between the neck and the first
lateral process. The first three joints are small and progressively increase in length,
the third being slightly curved and having a very oblique distal termination. The
fourth joint is rather longer than the three preceding ones together ; it is stout, curved,
and like them, scantily supplied with small sete. The fifth joint is very long and
slender ; owing to the curves it is difficult to measure precisely, but it appears to be as
long as or longer than the preceding four joints. Its distal half bears a bunch of
about forty large eggs, and is terminated by a short lobe. The sixth joint is quite
short; the seventh and eighth are longer and sub-equal; the ninth and tenth
progressively shorten, but only by a very little, the last one being slightly curved.
The terminal claw is worn down to a stump, but appears to have been slender. The
four terminal joints each bear a row of denticulate spines and a few small sete
dorsally. The spines are much worn, and only a flattened ovate leaf can be dis-
tinguished, with traces of three or four lateral teeth.

Fig. 3a is from a younger specimen.

The Legs are not very long, only attaining a length of about 23mm. Of the three
coxee the second-is quite as long as the other two together, and is enlarged distally.
The first shows a trace of a distal spur which gives it a rather angular appearance, and
the sete of the distal fringe arise for the most part on tubercular enlargements of the
joint. On the second coxa the setze are linear and dorsal, those of the mid-dorsal row are
socketed into small tubercular enlargements of the joint. The third coxa bears a few
small setee dorsally, and a poorly developed distal fringe ventrally. The three following
joints are very nearly equal in length, circ. 5mm., but the advantage is with the second
tibia. On the femur there are five rows of setee dorsally and laterally, three of which
are readily seen, the setee usually arising from a small tubercle ; the other two rows are
less conspicuous and contain fewer sete. In the mid-ventral line there is a row of
comparatively stout tubercles. On the two tibize the sete are very much more .
numerous, and their lmear arrangement and tubercular bases are less distinct. They
cover both dorsal and ventral surfaces, but a space above the lateral line is left bare.
The lateral line is distinct from the first coxa to the end of the second tibia. The
distal fringes, though present, are composed of setee of moderate size, and are therefore
inconspicuous. The tarsus is very small and cup-shaped, its ventral surface being

PYCNOGONIDA. 9

completely covered with stiff seta, largest distally. The propodus is curved, with a
very distinct swelling ventrally at the proximal end; this swelling bears half-a-dozen
strong spines, the rest of the ventral surface being occupied by a band of stout spinous
setee about half the size of the proximal group. Dorsally the sete are fewer and
weaker, a narrow space appears devoid of them laterally. The terminal claw is long
and slender, about two-thirds the length of the propodus, to which it is articulated at
the ventral angle. There are no auxiliaries, and the projecting heel is small.

The Genital apertures of the male occur on the second coxve of the two posterior
pairs of legs; in the female they occur on all the legs, on a conspicuous swelling of
the coxa.

The adult male bearing ova, described above, was taken in Winter Quarters in
125 fathoms, on a bottom of small stones and organic débris (June 6, 1903). A
smaller specimen, taken at the same time and place, is rather severely mutilated, having
lost one of its ovigers and four legs. Its sex is indeterminable, but it is probably
immature. ‘The first segment of the trunk is distinct; the others can be traced, but
with difficulty. The limbs are much more spinose than in my type; everywhere the
tubercular enlargements from which the stiff sete arise are more abundant, especially
on the first coxa and the femur. The oviger also is very different. The first three
joints are small, the third having an oblique termination which involves half its length ;
the fourth is as long as the two preceding, the fifth a trifle longer; the sixth is very
short, and the seventh scarcely twice as long. Of the three terminals the middle one
is the shortest, the other two being subequal in length. From the sixth each successive
joint becomes more slender. The entire appendage is completely devoid of sete, but
on the inner margin of the seventh joint are three curved spines; on the eighth joint
there are two, and on the terminal one there are six, one of them occupying the position
of the terminal claw. An adult female was taken in 41 fms. (Jan. 30, 1903). The
femora contain ripe ova and are swollen in consequence. The sete are generally
finer than those of the male. The oviger, too, resembles that of the male. The
denticulate spines are fairly well preserved, and under a high power (1” obj.) show a
short shaft with three small, but strong, teeth. Then follows a flattened ovoid blade
with a minutely toothed margin, the teeth of which are of a totally different character
to those on the shaft. On the terminal joint these spines are more curved than
elsewhere and the terminal claw does not exist, its place being taken by a much worn
example of the denticulate spines. Another occurs more dorsally, but is broken off in
this specimen.

I believe I am correct in identifying these specimens with the P. cornigera of
Professor Mébius and with the Cordylochele turqueti of Professor Bouvier. Though |
have seen both species, must admit that I have not examined them with that care that
the fact of a second closely allied species having been found demands.

The essential difference between the ‘Discovery’ and the ‘ Valdivia’ specimens
oceurs in the length of the legs, which are half as long again in the latter specimens.

N 2

10 T. V. HODGSON.

PSEUDOPALLENE AUSTRALIS.

(Plate L., fig. 2.)
Specific characters :-—
Body with lateral processes widely separated, these and the cephalon armed with stout spurs.
Limbs armed with rows of prominent tubercles which bear the sete. Propodus with few seta
dorsally and a proximal group of three or thereabouts.
Oviger ten-jointed, four terminal joints long and cylindrical. Denticulate spines without lateral
teeth at base.

Body rather robust, though more slender than in the last-named species ; lateral
processes widely separated, and but little longer than the trunk is broad. It is
smooth except for the spurs on the cephalon and lateral processes. These are similar
to but more upright than those of P. cornigera. The segmentation is distinct.

The Ocular tubercle is short, stout, rounded at the extremity, and bears four
large well-developed eyes. It rises just clear of the first pair of lateral processes.

The Abdomen is of normal proportions, rather ovoid in shape and without sete.
There is no articulation, and it is directed obliquely upwards.

The length of the body is 6mm. and its extreme width is 3mm.

The Proboscis and the Chelifori are as in the preceding species.

The Ovigers (fig. 2a) rise just behind the neck, each from a small body-process.
The first joint is very small and stout, the second equally stout, but much longer; the
third is more slender, and has the usual oblique termination, but is scarcely as long
as the two preceding joints; the fourth is nearly as long as the three preceding.
The fifth is much the longest of the appendage, slender and rather enlarged distally.
The sixth is quite small, about a quarter the length of the fifth. All these joints bear
a very few minute sete, all of which have traces of an enlarged base. The four
terminal joints are long and slender, with very little difference in their length ; the first
is longest, the next two are subequal, and the last the shortest. All are provided with
numerous denticulate spines, which occur in a single row (fig. 2b). They comprise a
rather conical shaft, surrounded by a flat leaf-like blade with a finely dentate margin.
There is no trace of the stout basal teeth so characteristic of the preceding species.
The end of the terminal joint bears two curved spines, which are obviously the same
denticulate spines worn down. The character of these four terminal joints differs from
those of the preceding species in their more slender and cylindrical form as well as their
greater length.

The Legs extend to a length of 23mm. Of the three coxe the second is quite as
long as the other two together; the proportions of the three following joints are as
6:5°5:5°5; the tarsus is very small, the propodus is curved, especially proximally,
and rather more than one-third the length of the second tibia. The terminal claw is
very long and slender; there are no auxiliaries, nor is there any heel. The sete, if
such they may be called, are small and delicate. They lie in lines parallel to the
surface of the jomt, and, with very few exceptions, each one occurs on a prominent

PYCNOGONIDA. 1]

tubercular process arched towards the extremity of the limb. They occur distally on
the first coxa, dorsally on the second, where there are two rows, and ventrally on the
third coxa. Elsewhere there are five rows in which the ventral tubercles are the
smallest. Between the two rows on the second coxa distally is a rounded tubercle
bearing no seta. The distal extremity of the second tibia is liberally provided with
small stout sete not connected with tubercles; its distal fringe is inconspicuous.
The tarsus is covered with setze which increase in length distally, forming a fringe of
long and stout sete. The tubercular character of the leg completely disappears on
this and the succeeding joint. On the propodus there is a scanty supply of minute
sete dorsally, and ventrally at the proximal end of the joint is a well-developed
enlargement bearing three spines of moderate strength; the rest of the ventral surface
is occupied by a band of small but fairly prominent spinous setie.

A single specimen of this species was taken off the Barrier, lat. 78° 25'40" S., long.
185° 39’ 6” E. in 300fms. Bottom, mud. ;

It is an adult female, with the Genital apertures prominent on the second cox of
all the legs.

PALLENOPSIS.

Body slender or robust, distinctly segmented.

Proboscis cylindrical, ventral in origin, flexibly united to the trunk.

Abdomen long and slender.

Chelifori well developed ; scape long, two-jointed.

Palps reduced to a more or less conspicuous knob.

Ovigers ten-jointed, present in both sexes, without a terminal claw or denticulate spines.

Legs with auxiliary claws. A tubular duct occurs in a mid-ventral position on the femora of the
male.

Ocular tubercle placed anteriorly on the cephalon, with two unequal pairs of eyes.

As above stated, the generic definition is much altered from the original of Prof.
E. B. Wilson (32). Besides the two new species described below, no less than thirteen
have from time to time been recorded, all of them from a strictly limited number of
specimens. They are separated by characters which, when committed to paper, do
not appear as definite as one would like. Nothing is known with regard to the
variation which may occur within the limits of “a species,” and so it must remain open
to question whether I have taken the right course with reference to P. hiemalis and

P. pilosa, Hoek, or not.

PALLENOPSIS GLABRA.

Pallenopsis glabra, Mébius (23), p. 184.
Specific characters :—
Body comparatively slender, with lateral processes widely separated, and with two small tubercles
dorsally.
Chelifori well developed, scape two-jointed, the whole limb minutely scabrous.
Palps reduced to a conspicuous stump.
Ovigers ten-jointed, without claw or denticulate spines.
Legs long, covered throughout with minute spinous sete.

12 T. V. HODGSON.

I am unable to find any satisfactory grounds for separating this species from that
of Professor Mébius. A full description follows, as that of Professor Mébius is scarcely
sufficient on small points. Body comparatively slender, with the lateral processes
widely separated and slightly increasing in length to the third, which is directed back-
wards.

The Cephalon is long, rather broader than the rest of the body, bevelled
anteriorly to form a median point, immediately behind which lies the stout ocular
tubercle. This is stout, erect, rounded in front, and terminating in a short spine on
the posterior half of the tubercle above the eyes. The four eyes are well developed,
the anterior pair being much the larger. The Ovigers arise on small body-processes
immediately in front, and rather below the level of the first lateral pair.

The Abdomen is very long, slightly curved, and with a clavate extremity ; it is
not articulated to the trunk, and is directed obliquely upwards at a considerable angle.
It is covered with minute curved spines.

The segmentation of the trunk is rendered conspicuous by a slightly raised ridge
forming the posterior border of the segment, these ridges are rather more prominent
ventrally, and in both cases bear a few minute spines, Similar spies occur on the
lateral processes, and form a distal fringe round them.

The Proboscis is movably articulated to the trunk and directed downwards, its
origin is ventral, and at the proximal end of the cephalon; it is cylindrical, tapermg
slightly, its distal extremity rounded and the mouth small. It is completely covered
with minute spines except for a narrow band in the mid-ventral line.

The Chelifori are well developed, and arise close to the middle line, their origin
occupying almost the entire width of the cephalon. The scape is two-jointed, and half
as long as the trunk measured to the base of the abdomen ; the two joints are sub-equal
in length, the second being expanded distally. The chela is directed downwards, the
palm rather curved, and fully as long as the other joints. The small dactyli are directed
inwards, the movable one having a spinous cushion at the base. The entire appendage
is covered with minute spines, largest and most numerous on the second joint of the
scape, the distal fringe of which is also more conspicuous.

The Palps are stout single-jointed stumps arising from the sides of the cephalon,
about the middle of its length.

The Oviger is ten-jointed. The first jot is very short and stout, the second is
much longer, clavate and setose on its outer margin; the third is shorter, curved, and
having a very oblique termination ; it is also setose on its outer margin. These three
joints form a curve in one direction, and the following three curve in another. The
fourth and fifth joints are comparatively long and sub-equal, both slightly curved, the
fourth setose on both sides, the fifth only on its outer margin; the sixth joint is short
and much curved, and from this one the remaining joints become shorter, more slender,
and more setose, the setze being longer than elsewhere. There is no terminal claw, nor
denticulate spines.

PYCNOGONIDA. 13

The Legs are long, attaining a length of 69mm. The lateral line is conspicuous,
beginning on the lateral processes and extending to the end of the second tibia. Of
the three coxze the second is longer than the other two together, all three are thickly
covered with small spimous sete on the ventral surface, but, except on the first coxa,
there are none dorsally. The proportions of the three following joints are as 17 : 14°5 : 21.
The femur is fairly well covered with minute sete ventrally; dorsally they are much
less numerous, except at the distal extremity. A linear arrangement of the sete is
observable, but it is not very regular, a distal fringe is not very prominent, and almost
confined to the dorsal side. On the first tibia the setee become more numerous dorsally,
they preserve the same general arrangement, but there are longer setee mixed with them.
On the second tibia this becomes much more pronounced, and ventrally the sete are so
numerous that the linear arrangement is completely obscured ; the distal fringe on both
joints is well developed, more especially so on the ventral side of the second tibia. The
tarsus is very small, the ventral surface being double that of the dorsal; the former is
covered with long spinous setze, most prominent distally, like those of the distal fringe
of the preceding joint, dorsally they are smaller, but form a well-developed fringe. The
propodus is slightly curved, and completely covered with small spinous sete, and some
of these form a distal fringe over the insertion of the terminal claw and its auxiliaries.
At the proximal end of the joint is a series of some half-dozen short spines, the centre
ones being the largest ; beyond these a group of stout spinous sete extends to the end
of the joint. The terminal claw is short, half the length of the propodus, and the
auxiliaries are about half its size.

Of the two specimens obtained one is a male, and the Genital apertures occur on
a slight swelling at the distal extremity of the second coxee of the two posterior pairs of
legs. On the ventral surface of the femur is a swelling about the middle of its length,
and this bears a short but stout duct characteristic of the males of this genus. The
Genital apertures of the female occur on a very pronounced swelling, in a similar
position to those of the male, but on all the legs.

This specimen is remarkable for having the first leg of the right side complete in
all essential details, but not extending beyond the distal extremity of the femur of the
normal limb.

Winter Quarters, off Flagon Point. January 17th, 1903. 5-20 fm. Very
rough ground.

PALLENOPSIS VILLOSA.
(Plate IL, fig. 1.)

Body robust, with lateral processes rather close together. Entire animal clothed with long,
slender sete, giving it a woolly appearance.

Chelifori well developed, scape two-jointed, no setous cushion at the base of the dactylus.

Palps reduced to a knob.

Oviger ten-jointed, without claw or denticulate spines,

Legs densely clothed with fine sete, propodus with several strong spines ventrally ; one or two
of the proximal ones are much the largest.

14 T. V. HODGSON.

Body robust, with the lateral processes distinctly, but not widely separated.
Segmentation is complete, and in the case of the trunk it is rendered very prominent
by each segment to some extent overlapping the following one ; this is most noticeable
ventrally.

The Cephalon is large, with a distinctly constricted neck. At its extreme anterior
end, which is straight, the stout rod-like ocular tubercle projects slightly forwards ;
this is rounded at its extremity, where there are four well-developed eyes, the anterior
pair very much larger than the posterior.

The Abdomen is lone and distinctly articulated to the trunk; it imcreases in
diameter to a short distance from its extremity, when it abruptly tapers to a blunt
point. About its middle it is provided with a considerable number of long slender
setee. Similar sete fringe the anterior border of the cephalon, the distal extremities
of the lateral processes, and the posterior border of each segment. None of these
setee are present ventrally. The length of the body is 10mm., and its width is 6*5mm.
The abdomen measures barely 4mm.

The Proboscis is stout, cylindrical, rounded at the extremity, and articulated to the
trunk on the ventral surface, and therefore directed downwards. The mouth is small.
It is liberally covered with short sete. In length it is scarcely half that of the body.

The Chelifori are long and chelate; they arise quite close to the middle line
underneath the anterior border of the cephalon. The scape is stout and two-jointed,
measuring some 5mm. in leneth; the two joints are sub-equal and covered with long
slender setze, the second joint more abundantly so, especially distally. These setze are
confined to the dorsal surface ; a row exists ventro-laterally, but ventrally they are
replaced by very short sete. The third joint, forming the chela, is directed down-
wards, and is shorter than the preceding. It is covered all over with sete, shorter
than the average, but varying in length from the proximal to the distal end; on the
outside of the movable finger is a dense tuft of long setee (fig. la). The dactyli are
turned inwards, the movable one being the longer. They are curved at the tips, which
cross over each other, and are devoid of teeth.

The Palps arise at the side of the proboscis, and are nothing more than rounded knobs.

The Ovigers are ten-jointed, and without terminal claw or denticulate spines
(fig. 1b). They arise ventro-laterally between the base of the proboscis and the first
lateral processes. All the joints are small, and the appendage is curved like an
attenuated §, and setose throughout. The first joint is small and stout, the remainder
gradually decrease in breadth ; the second is about twice as long as the first; the
third is intermediate between the two, and has a very oblique termination. These
three joints bear long setz on the outside of the curve formed by them. The fourth
joint is the longest on the appendage, and slightly curved ; it bears a few long sete on
the inner side, and numerous short ones on both. The fifth joint is not so long, also
slightly curved and dilated distally with long setee on its outer side. The sixth joint
is shorter and slightly curved; it is thickly clothed with long sete, and bears a few

PYCNOGONIDA. 15

on the opposite side distally. The seventh, eighth, and tenth joints are sub-equal
in length, and the ninth is a little shorter. The arrangement of the sete is the same
as on the sixth joint, except that the distal group on the outer side increases on each
joint, so as to involve the whole of it. The setze on the five terminal joints are very
long and quite simple.

The Legs are very stout, and some 36mm. in length. The first coxe are about as
long as their corresponding lateral processes ; the second are longer, and, in the female,
bear a conspicuous enlargement ventrally near the distal extremity, upon which the
large genital openings occur ; these are on all the limbs. The third coxe are about
the same size as the first. The three following joints differ but little in size, being
proportionally as 8°5:9:9°5. The tarsus is very small, and the propodus is about
a quarter the length of the second tibia. The entire limb is clothed with sete.
Dorsally the three coxze each bear a prominent distal fringe of long sete. The first
has two lateral bands in addition, while the other two are more completely clothed.
Ventrally the third coxa is partially covered with small sete, and has a prominent
distal fringe of longer ones, the other two only possess a distal fringe of short
sete. On the femur the dorsal surface is covered with long sete, which also form a
prominent distal fringe ; the ventral surface bears only small sete, but on each side
there is a band of the large ones just below the well-developed lateral line. This
arrangement holds good on the two tibiz, but the setee are much more thickly
set. At the distal extremity of the second tibia the setee become spinous ventrally,
and as spines form the distal fringe on that side. The ventral surface of the tarsus is
clothed with spines which are large distally ; dorsally there is a fringe of sete only.
The propodus is covered dorsally with sete of more moderate length than those on
the appendage generally ; laterally they are smaller still, and along the ventral
aspect there is a row of about a dozen strong spines, a little irregular in size,
but one or two of the proximal ones are much the largest. There is no projection of
the propodus beyond the insertion of the terminal claw, which is stout and rather
more than half the length of the joint that bears it. It is accompanied by two small
auxiliaries,

The single specimen is an adult female, and contains ripe ova.

Taken off Coulman Island in 100 fm., on mud and stones, January 13th, 1902.

PALLENOPSIS PILOSA.
(Plate II., fig. 2.)
Phovichilidium pilosum, Hoek (14). p. 90.
Pallenopsis pilosa, Hoek (16). p. 9.
Specific characters :—
Body not very robust, with lateral processes not widely but distinctly separated. Body (dorsally)
and legs covered with extremely long thin hairs.
Chelifori well developed, scape showing distinct articulation on the dorsal surface. No setose
pad at base of dactylus,

VOL, III, O

16 TS Ve HODGSON.

Body fairly robust, with lateral processes distinctly, but not widely, separated ;
two pairs directed forwards and the other two backwards.

Cephalon stout, longer than two segments of the trunk, cylindrical, with its
anterior border bevelled on each side; near the point thus produced les the Ocular
tubercle. This is short and stout, capped by a blunt point below which are four well-
developed eyes ; the anterior pair larger than the posterior pair.

The Abdomen is long and slender, terminating in a blunt point, and bearing
numerous long setee.

The segmentation of the body is perfect, and on the posterior margin of the three
anterior segments are two tufts of long slender sete, a number of which occur also
on the lateral processes, and also form the distal frmge. The ventral surface is devoid
of setee.

The length of the body is 10mm., its width 5mm. The abdomen measures 4mm.
in length.

The Proboscis is ventral in position, directed downwards and movably articulated
to the trunk. It is cylindrical, terminating in a blunt cone; mouth small, covered
with small setze 4mm. long.

The Chelifori are well developed; they arise close to the middle line in front of the
cephalon, and extend considerably beyond the proboscis. The scape is long and single-
jointed, though dorsally there is a slight enlargement about the middle of its length,
indicating a possibly fused joint. Numerous long and slender sete are distributed over
the scape. Distally the setee are smaller, and there is a strongly developed distal
fringe. The chelee are comparatively small, and hang vertically. The palm is scarcely
more than a quarter the length of the scape, covered with short stiff setae. The fingers
are small, and directed inwards at a considerable angle from the palms; the movable
finger is nearly twice the size of the other, but neither bears any trace of teeth.

The Palps are quite rudimentary, being nothing more than a small but conspicuous
rounded stump at the side of the proboscis, well behind the ocular tubercle when
viewed from the dorsal aspect. They bear a few small sete.

The Ovigers occupy a lateral position immediately in front of a shallow groove
separating the cephalon from the first lateral processes. They are ten-jointed (fig. 2).
The first joint is small and stout; the second is about three times as long, enlarged
distally ; the third is intermediate in length between these two; the fourth is long,
about as long as the two preceding joints, and very stout; the fifth is very little longer,
slightly narrowed in the centre, and expanded distally; the sixth is stout, and not
half the length of the fifth. All these joints bear a few short setee, most numerous on
the outer side of the fifth and sixth joints. The seventh joint is longer than the
sixth or the two following together; of these the proximal is shorter, the terminal
joint (missing in the appendage examined in detail) is quite small and without a
terminal claw. The last four joints bear long and stout sete of a simple character,
There are no denticulate spines,

PYCNOGONIDA. ys

The Leg attains a length of 32mm. Of the three coxe the second is about as
long as the other two together, and is much enlarged distally. The first bears a
mid-dorsal row of a few long setz and a distal fringe of the same kind. The second
bears two dorso-lateral rows and the distal fringe ; and ventrally, a conspicuous fringe
between the distal extremity and the genital apertures. The third coxa is covered
ventrally and laterally with setze and carries ventrally a very prominent distal fringe.
The proportions of the three following joints are 8°5:8°5:10, these joints are covered
with lines of very long slender setze, their great length making it difficult to determine
the precise number of rows. On the femur they are most abundant ventrally, except
near the distal extremity. On the two tibize the ventral surface is much more scantily
supplied. The distal fringe of the second tibia is rather spinous ventrally. The
tarsus is very small, setose, and with a few spinous sete at its ventral extremity.
The propodus is curved, covered with rather short sete, a fringe of longer ones distally ;
there is no heel. Ventrally at the proximal end of the joint are two or three stout
spines, and a band of smaller ones of irregular size extends to the end of the joint.
The terminal claw is long and slender, with two well-developed but not large auxiliaries.
Small sete also occur more or less abundantly throughout the limb.

The Genital apertures of the female occur on the enlarged part of the second coxa
of every lee. In the male these orifices occur at the apex of a pointed tubercle on the
two posterior legs only. The male as a rule is more setose than the female, and on
the mid-ventral surface of the femur there is the duct so characteristic of the males of
this genus ; in this species it is long and slightly twisted, conspicuous even among the
long sete. The joints of the ovigers up to the sixth joint are more strongly developed,
longer, and all are more setose than those of the female. One specimen has three
perfect ovigers, two on one side being in contact with one another. The eggs are
rather large, and held round each oviger in a single rounded mass.

Several specimens of this species were taken off the Ice Barrier in the Ross Sea,
300fm., mud bottom. Iam unable to find any satisfactory reason for separating them
from the species of Dr. P. P. C. Hoek. They are-smaller, and the only character which
can be used to separate them is the comparative length of the four terminal joints of
the oviger, but this does not seem to me to be sufficient.

PALLENOPSIS HIEMALIS.
(Plate I., fig. 4; Plate II., fig. 3.)

Body well built, with lateral processes widely separated, but of variable length, and having a
tubercular swelling at the dorsal extremity.

Chelifori and abdomen both proportionally long.

Palps, a rather long stump.

Legs clothed with short, stiff sete.

Body well built, with the lateral processes rather widely separated, as long as the

trunk is broad, and each bearing distally a stout tubercle of no great elevation.
0 2

—
(oe)

T. V. HODGSON.

The Cephalon is elongated, but not much enlarged in diameter, with a very
slightly constricted neck between the first pair of lateral processes and the small
body-processes from which the ovigers arise, and which are plainly visible dorsally.
The anterior margin of the cephalon is angular, and the Ocular tubercle arises at its
front. This is stout, directed very slightly forwards, and terminates in a point above
the four well-developed eyes; the anterior pair are larger than the posterior.

The Abdomen is long, not articulated to the trunk, and slightly enlarged before
it terminates in a blunt point; it is directed upwards to a moderate extent. The
length of the body is 11mm., its width 4°75mm., and the length of the abdomen is
375mm. A few small, stiff setee occur dorsally at the posterior margin of the segments
and at the extremity of the lateral processes.

The Proboscis is stout, cylindrical, rounded at the extremity; the mouth is
small. Ventrally it measures 4mm. in length and, except in the mid-ventral line, it is
closely covered with small, stiff sete. It is ventral in position, directed obliquely
downwards, and articulated to the trunk.

The Chelifori are well developed, and arise close together above and in front of the
proboscis. The scape is long and stout, projecting beyond the extremity of the proboscis,
though only 4mm. long. It is divided by a distinct joint into two sub-equal portions
and covered completely with short, stiff sete; the second joint is expanded distally
and has an oblique termination. The chela is well developed, the palm being rather
shorter than the joimts of the scape, but like them densely setose. The dactyli are
set on its inner extremity and lie transversely. They are short and stout, smooth
without teeth ; the movable one is the larger, and has a setose pad at the base.

The Palps are stout, single-jointed, rather long stumps; they arise from the sides
of the cephalon about the middle of its length.

The Ovigers are ten-jointed, without terminal claw or denticulate spines (fig. 4a).
The appendage arises on a small process of the body in front of the first lateral
process. The first ‘Joint is short and very stout; the second is at least twice as long,
slender proximally, much dilated distally ; the third is shorter, and the oblique
articulation of this joint with the next renders the fourth to all imtents and purposes
lateral; the fourth is the longest of the appendage and stout; the fifth shorter,
and the sixth shorter still. The limb is curved in the form of an §S, the first three
joints forming the curve in one direction, the three following curve in another.
Of the four terminal joints the seventh is short, the eighth is longer, the ninth and
tenth progressively shorten. The entire appendage is setose, the sete are small
and rather sparse proximally, becoming more numerous to the fifth joint; from that
joint onward they are longer, but quite simple, and more completely clothe the joints.

The Legs extend to about 388mm. Of the three coxze the second is fully twice as
long as the other two together, and bears a low rounded tuberele dorsally, just beyond
the middle of its length. The first coxa carries dorsally a stout but short tubercular
process, similar to, but smaller than, that of the lateral process. The proportions of

PYCNOGONIDA. no

the three following joints are 9:8°5:11°5. The tarsus is very small, and of the
normal shape. The propodus is one-third the length of the femur, very slightly
curved. At the ventral side of the extremity is a stout claw, with two well-developed
auxiliaries ; the heel does not project beyond the insertion of these claws. The joint
is uniformly clothed with short spinous setze, and there is dorsally a projecting fringe.
Ventrally there is a row of stout spines, of which some half-dozen, not very regular
in their position, are very prominent (fig. 3). The entire limb is uniformly and
densely clothed with very short, stiff setae, and these, as is usually the case, are more
numerous and longer on the second tibia; the distal fringe on this latter joint
is prominent, with at least one stout spine ventrally. The ventral sete on the tarsus
are also spinous, one being particularly large. The lateral line is very prominent
from the lateral processes to the tarsus, both inclusive.

The specimen is a female and bears Genital apertures on a swelling of the second
coxa of every leg.

Winter Quarters, inside the 20-fm. line.

A specimen was taken off Cape Wadworth, Coulman Island, which, notwithstanding
certain important differences, I cannot regard as being specifically distinct. It is a
male, and rather larger than the type. The obvious differences lie in the much
greater length of the lateral processes and the character of the ventral spines on the
propodus (fig. 3a). With regard to the first of these features, the third lateral process
of the right side is but little more than half the length of the others ; the first coxa, the
only joint of that appendage that exists, is also abnormally small, though there are no
definite traces of injury. The other feature rests on the armature of the propodus.
The ventral surface of this joint bears proximally three very stout spines, and from
there to the extremity is a band of spinous sete.

The length of the body is 12mm., of the trunk only 9mm., and its extreme width
is 6mm., rather larger, especially in the last measurement, than the type. The
chelifori (scape) and the abdomen are a little shorter. The oviger differs only in
being much stronger; the sete are more numerous and also stronger. The fifth joint
is however longer, nearly equalling the fourth. This is a not uncommon sexual
difference. The lateral processes and the first coxa exhibit in a less degree the
tubercular processes of the type.

The proportions of the three principal joints of the legs are 9°75 :8°5, and 12,
a difference of no importance. These limbs are setose throughout, though the sete
are rather deficient proximally, becoming much more abundant on the tibia. Ventrally
they are very small, stiff, and crowded ; dorsally much less numerous. They have among
them a number of much longer and more slender sete. ‘The tarsus is coarsely setose
ventrally, with one very prominent spine. The distal fringes of the joints are not
strongly developed ; that of the second tibia is chiefly ventral and spinous. The lateral
line is very distinct from the lateral process to the end of the second tibia. The femur
is swollen ventrally near the middle, and bears a very short but stout tubular duct.

20 T. V. HODGSON.

Another specimen, a male, was taken in Winter Quarters, inside the 20-fm. line
before the ship was frozen in. It is in a severely mutilated condition, having lost the
posterior segment of the trunk and several legs. It differs shghtly from the male
above described, the lateral processes being a little closer together and the body,
especially the cephalic portion, being a trifle stouter, and the tubercular knobs on
the lateral processes not being so distinct, but all these features can, I think, be
readily accounted for by age.

This species is closely allied to P. patagonica, Hoek.

NYMPHON.

This genus is perhaps the most widely distributed and best known of all the
genera of Pycnogonida. It is readily distinguished from all others by the well-
developed chelifori, the five-jointed palps, and the ten-jointed ovigers, the four terminal
joints of these being provided with a single row of denticulate spines. The form of
the body varies greatly within certain limits, and Professor Sars (25) has subdivided
the genus into three :—

Nymphon retains the more slender and comparatively long-legged species.

Cheetonymphon the more robust and short-legged species, which also, as a rule, are
more setose on the body than those of the original genus, Nymphon.

Boreonymphon, another robust form, readily separable from the others by the
absence of teeth on the chele, the spines of the ovigers being simple and not
denticulate.

The species brought back by the ‘Discovery’ are eight in number ; four are
assigned to the original genus, though one of these, V. adureanwm, bears a few simple
spines on the oviger instead of the rows of denticulate spines. The other four, of
which one, for the present at least, is regarded as a southern variety of a previously
described species, ate assigned to the genus Chetonymphon.

NyYMPHON HIEMALE.
(Plate III., fig. 1; Plate X., fig. 8.)

Specific characters :—
Body slender, with rather long lateral processes very widely separated. Limbs covered with very
minute sete.
Ocular tubercle stout and short.
Palps five-jointed, proportions of last three as 7:4 :5°5.
Oviger ten-jointed, denticulate spines rather numerous, with eight to ten teeth on each side.
Legs long, scabrous, terminal claw with well-developed auxiliaries.

Body smooth, slender, with rather long lateral processes, which are very widely
separated; the first of these is curved forwards. The segments are very strongly
marked immediately behind the lateral processes.

The Cephalon is long, the greater part of its length is taken up by a slender

PYCNOGONIDA. 21

neck ; anteriorly it is much expanded, the two lobes being separated by a small but
conspicuous groove.

The Ocular tubercle is situated immediately in front of the first lateral
processes ; it is comparatively stout, short, truncate, and bears four well-developed
eyes without any pigment.

The Abdomen is small, ovoid, does not project beyond the last pair of lateral
processes, and is not articulated to the trunk. The length of the body is 7-5mm. and
its width is almost 4mm.

The Proboscis is cylindrical, smooth, and directed obliquely downwards; it is
about 3mm. in length.

The Chelifori are well developed. The scape is as long as the proboscis, slightly
curved and sparsely covered with minute sete ; the distal fringe is not conspicuous.
The chelz are also curved, half their length being taken up by the palm, which
is finely setose, the sete extending on to the base of the immovable finger. The
fingers are slender, much incurved at the tip. The teeth are numerous and regular
in size, not so closely set in the immovable finger as in the other.

The Palp is slender, five-jointed, and rises at the side of the proboscis below the
chelifori (fig. 1a). The first joint, as usual, is very small; the second is the longest of
the appendage, slightly swollen distally, and sparingly covered with minute sete. The
third joint is but a little shorter, rather stouter, and more liberally supplied with
short sete, though these are still scanty. The fourth joint is scarcely half as long
as the second, very richly supplied with short sets on its ventral margin, much
more sparingly dorsally. These three joints have a well-defined distal fringe. The
terminal joint is nearly half as long again as the preceding and, like it, richly clothed
with short setze ventrally, more sparingly dorsally.

The Oviger is ten-jointed, and arises ventro-laterally in front of the first lateral
process on a prominent body-process, the position of which is clearly seen from the
dorsal surface (fig. 1b). The first three joints are small and stout, the third
curved and having a very oblique termination; only a distal fringe of very
small sete can be detected on these joints. The fourth joint is very long, slightly
curved, with very few minute sete besides the distal fringe. The fifth joint is
much the longest of the appendage, and is thinly covered with very small sete,
with a more strongly marked distal fringe. The sixth joint is little more than
half as long as the preceding, slightly curved, and thickly clothed with small
stiff setee on its outer side and a well-developed distal fringe. The four terminal
joints are long, progressively decreasing in length, but the last two are sub-equal.
All are more or less well supplied with short stiff setze dorsally and a distal fringe
of rather longer sete. The terminal claw is long and slender, with about fourteen
eurved teeth. The denticulate spines are long, and in the specimen critically
examined occur 13 : 10 : 10 : 9 on the various joints. (Plate X., fig. 8.) The shaft is
flattened and slender, and carries eight to ten teeth on each side; the third or fourth

22 T. V. HODGSON.

from the base is the largest, the remainder tapering off to very minute proportions.
The eggs are small and the spherical mass is packed round the proximal part of
the fifth joint.

The Legs are long and slender and attain a length of about 45mm. The second
leg of the right side has in this case been selected for measurement. Of the
coxee the first and third are sub-equal, the second being quite as long as the
other two together. The proportions of the three following joints are as 10: 11: 16,
and the tarsus and propodus taken together are 4°5, the former joint being a little
the longer of the two. A lateral line is plainly visible on the femur and to the
end of the leg. On the femur such sete as exist are extremely minute; on the
second tibia they are very numerous but small, arranged principally dorsally and
ventrally, with a distinct distal fringe. On the tarsus and propodus the arrangement
is the same, but the sete are even more crowded. Ventrally on the propodus is a
row of about a dozen comparatively strong spines, more distally than proximally.
There is a distinct heel fringed with rather long sete. The terminal claw is stout
and accompanied by two auxiliaries about one-third its size.

The Genital apertures of the male are found on the second coxze of the two
posterior legs, those of the female being found on all the legs.

A number of specimens were taken in Winter Quarters in 125 fm.

NyYMPHON LANARE.
(Plate III, fig. 2; Plate X., fig, 9:)

Specific characters :—
Body very slender, with lateral processes long and widely separated.
Ocular tubercle short and stout.
Palps five-jointed, proportions of last three 10: 9: 11.
Oviger ten-jointed, denticulate spines, about double the number on the first joint as on any of
the others, with fiye to seven teeth on each side.
Legs long and slender, with long and fine sete, terminal claw long, without auxiliaries.

Body very slender, with lateral processes long and very widely separated.

The Cephalon is long, expanded anteriorly into two lobes separated by a narrow
groove. The neck is elongated, and at-its base, ventrally, are small body-processes
for the attachment of the ovigers, visible from the dorsal aspect.

The Ocular tubercle is short, stout, and truncated ; it lies immediately in front, but
not quite clear of the first pair of lateral processes. It bears four well-developed eyes.

The Abdomen is quite small, and does not extend as far as the posterior lateral
processes. It is directed slightly upwards, and not articulated to the trunk. The
lenoth of the body is 8°5mm., and its width 5mm.

The Proboscis is cylindrical, slightly swollen in the middle, its extremity being
rather angular. Together with the body, it is quite devoid of sete.

The Chelifori are well developed, long and slender. The scape is single-jointed,
longer than the proboscis, but scarcely as long as the chela. It bears but few sete,

PYCNOGONIDA. 23

except a distal fringe of long and slender ones. The palm of the chela occupies
about half its length, and bears a number of fine setz dorsally. The fingers are
long, slender, incurved at the tips, and provided with numerous slender teeth,
irregular in size and not very closely set.

The Palp arises laterally at the side of the proboscis (fig. 2a), and comprises the
normal five joints, all of which, except the first, are very long and slender, the pro-
portions being 10:10: 9:11. Sete are non-existent on the first two joints; on the
third scanty, most numerous on the terminal joint, but not very thickly distributed
there ; they are small, rather delicate, and occur mainly on the outer side of the limb.

The Oviger has the normal ten joints, and arises on a small ventro-lateral body-
process just in front of the first pair of lateral processes (fig. 2b). The first three joints
are small, but progressively lengthen, the third having the usual oblique termination.
The fourth joint is long, the fifth longer, and the sixth still long, though the shortest
of these three, the proportions being about 7: 8:5. The sixth joint is rather thinly
covered with small sete on its outer side, and has a well-developed distal fringe.
The preceding joints have so few minute sete between them that they are scarcely
noticeable. Of the four terminal joints, the first is about twice the length of the next ;
the other three differ very little in size, but the middle one is the smallest. All are
provided with a few small setee and distal fringes. The terminal claw bears a dozen
slender teeth rather closely set. The denticulate spines form a single row (plate X.,
fig. 9). They consist of a stout shaft, which begins to taper at about a quarter of its
length, where the denticulations begin. Of these there are from five to seven; the
first is small, the next three large, and the remainder more or less vestigial. Of
these spines there are 10 : 5 : 4 : 5 respectively on the various joints.

The Legs are long and slender, attaining a length of nearly 45mm. The three
coxee are long, the second being longer than the other two together ; these joints are
rather scantily clothed with sete of no great length. The proportions of the following
joints are 8°5 : 9°5 :12:4:3. ‘he terminal claw is very long and slender, more than
half the length of the propodus, and there are no auxiliaries. The limb is clothed with
setze, not very closely set, in a linear manner. On the femur and tibia they are very
long and slender, becoming reduced in size on the tarsus, while on the propodus they
are very small.

Two examples of this species were taken off the Barrier in 300fm., bottom mud,
27th January, 1902.

NYMPHON ADAREANUM.
(Plate III., fig. 3.)

Specific characters :—
Body smooth and slender, with lateral processes widely separated.
Ocular tubercle short, rounded.
Palps five-jointed, proportions of last three 2°5 : 1°25 : 1°75.
Oviger ten-jointed, without denticulate spines, but with very few simple curved spines.
Legs of moderate length, with rather long sete, terminal claw with two well-developed auxiliaries.

VOL, III. P

24 T. V. HODGSON.

This small species has a fairly well-built body, with the lateral processes rather
widely separated, and as long as the diameter of the trunk. The trunk articulations
are very distinct, and immediately behind the lateral processes. No setee of any kind
are to be seen on the body.

The Cephalon is stout but not widely expanded, showing two distinct lobes for the
reception of the chelifori; it is not quite as long as the second and third trunk
segments together.

The Ocular tubercle is very stout, of small elevation, rounded at the summit, and
carries four well-developed eyes. It lies just in front of the first pair of lateral
processes and behind the neck.

The Abdomen is of moderate dimensions, curved upwards, and not separated by
an articulation from the trunk.

The length of the body is 2°75mm., and its extreme width 1°5mm.

The Proboscis arises on the ventral side of the trunk, and measured ventrally it
is nearly one-third the length of the entire body. It is stout, gently tapering to a
rounded extremity, quite smooth.

The Chelifori are well developed; the scape is single-joited, extending beyond
the proboscis ; provided laterally with comparatively long sete. The chela is not very
long, the palm and fingers occupying approximately equal halves; the former is
covered with sete, and the fingers, rather curved, are supplied with a very moderate
number of slender teeth rather widely separated.

The Palp is five-jointed, and rises underneath the chelifori (fig. 3a); as usual, the
first joint is very small and the second long. Owing to distortion in mounting this
appendage, the comparative length of the second and third jomts cannot be very
accurately stated, but the second appears to be twice the length of the third; the
fourth is half the length of the third, and the fifth is longer than the preceding, the
proportions being 5 : 2°5 :1:25:1°75. The terminal joint is ovoid, and fairly well
supplied with comparatively long sete ; the three preceding joints have well-developed
distal fringes and a small number of setee scattered along the shaft; these are most
numerous on the third joint.

The Oviger is ten-jointed, and rises from a small process of the trunk, visible
dorsally, just in front of the first pair of lateral processes (fig. 3b). The first three
joints are very small; the second and third are subequal in length, the latter much
the more slender; the fourth is longer than the three preceding ones together; the
fifth is twice as long, much curved, and bears a few sete on its outer margin; the
sixth is half as lone as the fourth. The four terminal joints are very small, the first
being the largest, and all bear two or three long sete distally. The terminal claw is
long and slender, with five slender teeth set at irregular intervals. Of denticulate
spines, such as characterise the genus Nymphon, there are none, but of special spines
there are 2:2:2:1 0n the four joints; these are curved blades without any other
distinguishing feature.

PYCNOGONIDA. 25

The Legs are not very long, extending to nearly 11mm. from the trunk. Of the
three coxe, the second is as long as the other two together, the first being by a little the
smallest ; the proportions of the remaining joints being 4:5:6:0°75:2. The terminal
claw is large and stout, with two well-developed auxiliaries. The lateral line is distinct
throughout. The sete have a rather indistinct linear arrangement, those on the
sides of the coxe are prominent, especially on the second; on the third they are more
confined to the ventral surface, and the distal fringe is fairly well developed. On the
femur the sete are long and straggling, chiefly lateral, and ventrally there is a row of
small tubercles. On the two tibize, but more especially the second, the setze are most
abundant, largest on the first. Ventrally they are much smaller, the distal fringe of
the second tibia becoming spinous. The tarsus is a very short joint with lone sete
dorsally, smaller and more numerous ones ventrally, which become delicate spines
distally. The propodus is covered with setee dorsally, and ventrally there is a row of
rather strong spines, and of these the middle ones are strongest.

The single specimen is a male, carrying young, apparently just hatched. The
Genital apertures are to be found on the second coxe of the two posterior pairs
of legs.

From the root of a Laminarian taken in 17 fm., Cape Adare, 24th February, 1904.

NYMPHON FRIGIDUM.

(Plate III., fig. 4; Plate X., fig. 10.)
Specific characters :—
Body very slender, with lateral processes long and very widely separated.
Ocular tubercle very short, stout.
Palps five-jointed, proportions of last three 3: 1:5: 3.
Oviger ten-jointed, denticulate spines not very numerous, with five to seven lateral teeth.
Legs long and slender, propodus with ventral row of spines, a large terminal claw and two
auxiliaries.

Body well built, perfectly smooth, with the lateral processes widely separated and
rather long, much more slender than the trunk.

The Cephalon is rather long, with a distinct neck and expanded anteriorly into
the two normal lobes.

The Abdomen is short, directed obliquely upwards, and not projecting beyond
the posterior pair of lateral processes.

The Ocular tubercle is stout, very short, and bears four well-developed eyes.

The length of the body is 2mm., and its extreme width is 1* 2mm.

The Proboscis is cylindrical, directed downwards.

The Chelifori comprise a single-jointed scape, slender, and covered with a small
number of fine setee. The chele are well developed, the palms being about half their
length, and setose ; the fingers are not much curved, provided with a number of teeth,
not very closely set, and of uniform size.

The Palp is five-jointed and rises underneath the chelifori (fig. 4a). The first

PZ

26 T. V. HODGSON.

joint is small, and the proportions of the remainder are 4:3:1°5:3. The terminal
joint is well supplied with sete on the outer side, and the preceding one is similarly,
but less well, provided. Elsewhere they are scanty, a few on the third, and only an
occasional one on the second.

The Oviger is ten-jointed, and rises from a small process immediately in front of
the first pair of lateral processes (fig. 4b.) The first joint is very small, the two
following are longer and subequal, the third having as usual a very oblique termination.
The fourth and fifth joints are subequal, and each much longer than the first three
together ; the sixth is half as long as the preceding. Of the four terminal joints the
first is the longest, the rest differ but little, but the last is longer than the others,
and bears a terminal claw with some half-dozen teeth. A limited number of sete
occur on all the joints from the end of the fourth. The denticulate spmes are not
very numerous, 8: 5:4: 5, and consist of a slender tapering shaft with from five to
seven lateral teeth ; the second from the base is strongly developed, the rest graduated
to nothing (plate X., fig. 10).

The Legs are long and very slender; they are about 9mm. long. Of the three
coxze the second is longer than the other two together, the proportions of the remaining
joints being 4: 4°5:7:1:1°5. The terminal claw is more than half as long as the
propodus, and is accompanied by two slender auxiliaries. The entire limb is rather
thinly clad with sete, which, as usual, are most abundant on the second tibia. The
propodus bears ventrally a row of comparatively strong spines, not very regular, the
middle ones being generally best developed.

This is not a mature form, and the sexual apertures cannot be distinguished. I
am unable to identify it with Nymphon hiemale, though it occurs in the same locality,
and feel compelled to regard it as an independent species.

g CHAETONYMPHON VILLOSUM.

DY a : r
(Plate IV., fig. 1; Plate X., fig. 11.)
Specific characters :—
Body robust and with the appendages covered with long and fine setz ; lateral processes close
together.
Ocular tubercle rather tall, with four eyes at summit.
Palp five-jointed, proportion of last three 6 : 2 : 3.
Oviger ten-jointed, denticulate spines not numerous, having five to seven lateral teeth on each side.
Legs short, with a strong terminal claw and two well-developed auxiliaries.

Body very robust and, with the appendages, covered with long and fine sete.
The lateral processes are close together, and these, being stout, give the body a compact
ovoid form.

The Cephalon is short, much expanded, and the neck, which thereby becomes
distinct, is scarcely a real constriction, the expanded portion being divided into two
distinct lobes, bearing a few long sete distally. Similar sete occur dorsally on

PYCNOGONIDA. 27

each segment of the trunk and on the lateral processes, in addition to the distal
fringe. There are none ventrally.

The Ocular tubercle rises from the neck immediately in front of the first pair of
lateral processes ; it is moderately tall, cylindrical, and bears at its rounded summit
four well-developed eyes.

The Abdomen is long and slightly ovate ; it projects beyond the first coxee of the
posterior pair of legs in their normal position, and bears a few small sete.

The length of the body is 6°5mm. and its width is scarcely 4mm.

The Proboscis is stout, cylindrical, and inclined downwards ; it is quite devoid of
setee of any kind, and 2°5mm. long, measured dorsally.

The Chelifori are strongly developed; the scape is stout and single-jointed ; it
bears on its inner margin a band of long sete: and a distal fringe of similar sete, but
these are much reduced in size on the outer side. The chela is strong, the palm is
setose all over and well on to the base of the immovable finger. These sete are of
normal size. The fingers are inclined at a considerable angle with the palm, and are
curved at the tips, especially the immovable one. Both are provided with numerous
slender teeth, not very closely set, and variable in size; these teeth may be said to
be large and small, but they are not disposed with any regularity.

The Palp has the normal five joints and arises at the side of the proboscis
(fig. 1a). The first joint is very short and stout; the second is the longest; this is
stout, dilated, curved at its distal extremity, sparsely covered with long setee and much
more abundantly with fine ones. The third joint is nearly as long, as 8 to 10,
and more abundantly supplied with both kinds of sete, which occur throughout
the appendage. The fourth joint is short and richly setose; the fifth is about half
as long again as the fourth, and also richly setose.

The Ovigers arise ventro-laterally, immediately in front of the first pair of lateral
processes (fig. 1b). Of the orthodox ten joints the first three are quite small, the
last being slightly curved, longer than either of the other two, and with an oblique
termination. The fourth joint is long, the fifth is longer still, the sixth about half
the length of the preceding. All these joints are covered with very fine sete; on
the first four there is an occasional longer and coarser seta, and on the fifth joint these
are more conspicuous on the outer margin and distal extremity ; on the sixth joint
they cover it on the outer side and form a well-developed distal fringe. Of the four
terminal joints the first three progressively shorten without any conspicuous difference
in size; the terminal one is a little longer than the preceding, and bears a slender
curved and dentate claw half as long again; there are eleven slender teeth on the claw.
The denticulate spines are not numerous on these joints, 5: 4:3: 4, and are of the normal
type, the shaft bearing five to seven lateral teeth. The spines on the proximal joint
are the largest. (Plate X., fig. 11.)

The Legs are short and robust, only attaining a length of 17mm. Of the three
cox the second is a little the largest ; they all bear a few long sete dorso-laterally, the

28 T. V. HODGSON.

third coxa being the most deficient in this respect. The distal fringe is well developed
ventrally on the second coxa, but more so on the third, and the ventral surface of this
joint is covered with small setee. The femur is short and stout, approximately equal
in size to the second tibia, the first being a little longer. The sete on these three
joints are arranged in a thoroughly characteristic manner. There are two dorso-lateral
rows and a lateral row, all of long, slender sete. There is also a ventral row of com-
paratively short sete, five rows in all. The setee are much better developed on the
second tibia than elsewhere. The distal fringes on these joints are normally
developed ; on the tibize they are ventral and spinous, more especially on the second
tibia. The tarsus and propodus are short and much more slender than the rest
of the limb. The two joints differ but little in size, the propodus being a little
the longer. This bears a stout terminal claw and two well-developed auxiliaries.
The sete of these two joints are small, but have the same arrangement as on the
other joints. The ventral row is, however, distinctly spinous, and a very prominent
spine exists at the ventral end of the tarsus.

Only one individual of this species was taken, and its sex has not been determined.

Coulman Island, 13 January, 1902; 100 fathoms, stony bottom.

CHETONYMPHON BIARTICULATUM.
(Plate IV.,. fie. 25- Plate XX.) fey as)
Specific characters :-—

Body stout, tapering posteriorly, articulation deficient, lateral processes separated by variable
intervals.

Ocular tubercle long and slender.

Palps five-jointed, proportions of last three as 3:1: 1.

Oviger ten-jointed, denticulate spines not numerous, and with not more than five small teeth on
each side.

Legs of moderate length, covered with rather fine sete, terminal claw with small auxiliaries.

Body is stout and tapering posteriorly, with the lateral processes separated by a
moderate interval, except the last two pairs, which are quite close together, the articu-
lation between them being deficient. The distal extremities of the ‘lateral processes are
provided with slender spines, but these have enlarged bases and thereby become more
prominent.

The Cephalon is short and stout, a very distinctly constricted neck separating
the expanded portion, which forms two diverging lobes.

The Ocular tubercle lies immediately behind the neck and in front of the first
pair of lateral processes. It is tall, slender, cylindrical, and bears four well-developed
eyes at the extremity ; there is no pigment.

The Abdomen is rather long, narrow, tapering to a blunt point, and not separated
from the trunk by an articulation.

The entire body is covered with very fine sete, not easy to distinguish, and in
addition there are two long setee dorsally near the posterior border of each segment,

PYCNOGONIDA. 29

two on each of the cephalic lobes, and one in the middle of each lateral process ; these
also possess dorsally a distal fringe of stout sete with enlarged bases. The ventral
surface appears to be quite devoid of sete.

The length of the body is 9mm. and its width scarcely 5mm. The length of the
trunk only (to base of abdomen) is 6mm.

The Proboscis is stout, cylindrical, and has a length, measured dorsally, of 3mm.
It is covered with very fine but comparatively long sete.

The Chelifori are well developed. The scape is single-jointed, reaching beyond the
proboscis; it is stout and provided with rows of setee having very stout bases
and a few others as if misplaced. The distal fringe is very prominent, especially on
the inner side. The chela approximately divides its length between the palm and the
fingers ; the former is covered with short and comparatively fine sete, and these are
continued well on to the base of the immovable finger. The fingers are inclined
inwards, slender, much incurved at the tips, and furnished with a number of slender,
closely-set teeth of fairly regular size.

The Palp arises laterally immediately below the chelifori (fig. 2a). The first joint
is small and stout, the second is long, and extends nearly to the end of the proboscis ;
the third is shorter; the two terminal ones subequal and together shorter than
the third, the proportions of the four joints being 5:3:1:1. The second joint is
uniformly covered with fine setee, as are the others. The sets become more numerous
and both longer and stiffer towards the extremity of the appendage.

The Oviger rises ventro-laterally immediately in front of the first lateral process ;
it consists of the normal ten joints, and is covered throughout with very fine delicate
setee (fig. 2b). Other and stiffer setee occur sparingly on the fifth joint, more
numerously on the sixth and the distal fringes of most of the joints, particularly the
terminal ones. The first three joints are small, but progressively lengthen, the third
having a very oblique termination. The fourth is a trifle longer than the first three
together, the fifth is longer still, and the sixth is half the length of the fifth. The
four terminal joints progressively shorten, the third being practically half the leneth of
the first; the terminal one bears a slender curved claw, as long as itself, with nine
slender teeth. The denticulate spines are not numerous, 7: 5:4: 4 (Plate X., fig. 12).
They consist of a flattened tapering shaft with not more than five lateral teeth on each
side, none of them large, and occurring nearer the base than usual, leaving the terminal
portion of the shaft free. They do not appear to be much worn.

The Legs are not very long, extending to about 25mm. Most of the joints are
very stout, but the tarsus and propodus are considerably reduced in diameter. Of the
three coxze the second is the largest, but not so long as the other two together ; the
proportions of the remaining joints are 5°5:6:5°5:3:2. The entire limb is clothed
with fine setee, but in addition to these are conspicuous rows of spinous sete arising
from enlarged bases. Two dorso-lateral rows occur on the first two cox, two rows
occur dorsally on the femur, but here the spines are small; the two lateral rows are

30 T. V. HODGSON.

much larger; but ventrally, this jomt and the coxee also are covered with normal sete.
These spines are best developed on the first tibia, two dorsal and two lateral rows
being conspicuous, a ventral row of much finer spines occurs. On the second tibia all
these five rows occur, but the spines are rather finer. The sete of the two terminal
joints are small without the enlarged bases, but arranged in the same manner. The
terminal claw is long and slender, and is accompanied by two quite small auxiliaries.
The distal fringes of the various joints do not present any unusual features.

The single specimen is a female, the Genital apertures are conspicuous on the
second coxee of all the legs.

Off the Barrier. January 2

190%. 300 fms. Mud.
39! 6” BR.

>
fe)

i
Lat. 78° 25' 40" S., long. 185°

CH&#TONYMPHON MENDOSUM.

(Plate IV., fig. 3; Plate X., fig. 13.)
Specific characters :—

Body robust and tapering, articulation imperfect, lateral processes not widely separated, and with
stout spines distally and dorsally ; no fine setae whatever.

Ocular tubercle short and stout.

Palp five-jointed, proportions of last three 5-5 : 1:5: 1°6.

Oviger ten-jointed, denticulate spines few, with four teeth on each side, two of them prominent.

Legs with five rows of spinous sete, without enlarged bases; terminal claw with two small
auxiliaries.

This species is very closely allied to the last, but is much smaller, and presents
other differences which are usually regarded as of specific rank.

The Body is robust and slightly tapering, with stoutly developed lateral processes,
the intervals between which are variable, widest but not very wide between the first
and second pairs; the third and fourth being quite close together, the articulation
between the two posterior pairs is not present.

The Cephalon is short, anteriorly expanded into two diverging lobes; the neck
is distinct, but very little constricted.

The Ocular tubercle lies behind the neck, but not clear of the first pair of lateral
processes.

The Abdomen is horizontal, long, extending considerably beyond the first coxa,
ovoid, tapering to a blunt point; it completely fills the space between the two posterior
lateral processes. All this is in close agreement with the preceding species. The
differences are :—The complete absence of fine sete from the entire body; the ocular
tubercle is rather short, stout, and slightly inclined forwards, carrying four well-
developed eyes with pigment on its rounded summit; the lateral processes all
provided with two or three stout spines dorsally and distally ; the spinous setee of the
legs, while having the same arrangement as in the preceding species, are, on the whole,
stronger in themselves, but without the enlarged bases.

The length of the body is 6°5mm., and its width just exceeds 3mm.

PYCNOGONIDA. 3]

The Proboscis is of moderate length, 2mm., measured dorsally, cylindrical but
slightly swollen in the middle ; it is directed downwards, and not setose at all.

The Chelifori are well developed ; the scape is single-jointed, stout, and scarcely as
long as the proboscis. A row of stout spines runs along its inner border, and a few
spinous setze constitute a distal fringe, and there are two or three scattered on the
shaft. The chela is strong, the palm taking up half its length, and the fingers are
set at a considerable angle. The palm is covered, but not thickly, with sete. The
fingers are slender, curved towards the tip, and provided with slender teeth of fairly
uniform length, but not very closely set.

The Palp rises laterally, quite close to the proboscis, and consists of the normal
five joints (fig. 3a). The first is short and stout, the second is the longest of the
appendage and provided with a few long sete; its proportion to the remainder is
9:5°5:1°5:1°6; the third is scantily supplied with sete, the two terminal joints are
rather more abundantly supplied ; the last joint is ovoid instead of cylindrical.

The Ovigers arise ventro-laterally immediately in front of the first pair of lateral
processes. They comprise ten joints of normal character (fig. 3b). The first three
joints are quite short, stout, and progressively lengthening ; the proportions of the three
following are 7:9:5. Sete become prominent, but not numerous, on the fifth and sixth
joints ; on the preceding joints they are almost non-existent. The four terminal joints
are small, the proportions being about 45:23:25: 2°75, the last one possessing a
curved terminal claw, quite as long as the joint, with half-a-dozen rather widely
separated teeth. All the terminal joints carry a few sete distally and dorsally. The
denticulate spines are not numerous, 5:4: 3:4 respectively ; they consist of the normal
flattened blade with two prominent teeth on each side, and two others of which traces
remain. They are rather worn. (Plate X., fig 13.)

The Legs are rather short, about 16mm., very stout, but the tarsus and propodus
are very much reduced in diameter. Of the three coxze the second is much the longest,
but not so long as the other two together. The first is provided dorso-laterally with
two stout spines, and there is another rather smaller one laterally, on the posterior
side. A row of spinous sete occur laterally on the other two coxe. The distal
fringes of these two joints are ventral and inconspicuous; that of the third coxa
is the best developed, and on this joint there are several small sete ventrally in
addition. The three following joints are subequal in size, the tarsus and propodus
together are three-quarters the length of the preceding joint, and are themselves sub-
equal. In these particulars this species is not in agreement with the preceding. On
the two tibize there are two dorsal rows of stout spinous sete, a lateral row on either
side, and a strongly developed ventral row. On the second tibia the distal fringe
is strongly developed ventrally, and spinous. The sete on the femur are smaller,
and only the two dorsal rows are distinct; the other three rows are present, but
very feebly developed; there is a prominent distal fringe dorsally. The tarsus and
propodus are similarly provided, but the sete are much smaller. The terminal claw

VOL, II. Q

32 T. V. HODGSON.

is stout, not half the length of the joint that bears it, and provided with two small
auxiliaries.

The specimen described above is an adult female with Genital apertures on the
second coxee of all the legs. Nearly mature ova can be seen in the femora.

It was taken in Winter Quarters, in 125fm., 24 April, 1903. Bottom : small stones,
organic débris, polyzoa, shells, etc. Other specimens, generally smaller, were taken at
the same place on various dates, and also at other points three and nine miles away, and
at the same or greater depths, 180 fm. They all appear to be sexually mature, and
differ in a varying degree from the type in their spinose character. In all cases this
is more conspicuous in the males. The Genital apertures of the male are on the two
posterior pairs of legs only.

The numerous minor features which separate this species from the preceding
cannot, in my opinion, be ascribed to age. The form of the ocular tubercle readily
separates the two.

A specimen was taken in 125 fm. on 3 May, 1903, and is, I think, a young form
of this species. The differences between this specimen and the adult individuals are :—

The posterior articulation of the trunk is present, but very much less distinct than
the others.

Palps: the second joint is as long as the three following together. The third joint
is as long as the two terminals together, and of these the last is a little the longer.

Ovigers: these are quite rudimentary, small, and hook-like; no joints are
differentiated, though two are indicated.

Legs: the proportions of the joints differ somewhat and are, beginning with the
femur, 6:7: 7: 2°25: 3°5. The limb is clothed with comparatively strong spinous setz
of some length, not very numerous, arranged in lines.

CHATONYMPHON AUSTRALE.
(Plate X., fig. 14.)

Nymphon australe, Hodgson (10), p. 257.
Chetonymphon altioculatum, Mobius (28), p. 181.
Specific characters :—
Body robust, with lateral processes not widely separated but divergent ; entire animal rather
coarsely setose.
Ocular tubercle long and slender.
Palps five-jointed, proportions of last three as 7 : 4°25: 4.
Oviger ten-jointed, denticulate spines fairly numerous, with four distinct lateral teeth on each side.
Legs short, tarsus a little longer than the propodus, the terminal claw with very minute auxiliaries.

Body robust, with stoutly developed lateral processes, which are distinctly though
not widely separated, the interval increasing with age; the body, exclusive of the
anterior part of the cephalon, forming an oval of graceful proportions.

The Cephalon is expanded, and the space between the chelifori is marked by a deep
groove, wide anteriorly. The neck is well defined, and behind this is the Ocular

PYCNOGONIDA. 33

tubercle, a structure which varies considerably in shape and size. As a rule it is rather
stout, and bears four well-developed eyes, with a variable amount of pigment. It is
slightly flattened antero-posteriorly, and more or less rounded at the extremity. The
cephalon and the lateral processes are provided with several long sete, the latter also
having a distal fringe.

The Abdomen is of moderate dimensions, pyriform, and rather thickly setose, not
separable from the trunk by an articulation.

The Proboscis is cylindrical, slightly enlarged about its middle. It is directed
downwards, and movably articulated to the trunk. No sete are apparent on its
surface.

The length of the entire body is 8mm. ; of the body only, 6mm. ; of the trunk, to
the insertion of the abdomen, 4°5mm._ Its width is 3mm.

The Chelifori are well developed ; the scape is a single joint longer than the
proboscis, liberally provided with long sete of irregular size, and also having a well-
marked distal fringe. The chele are slender, about as long as the scape. The palm
occupies half the length of the entire chela, and is covered with comparatively long
setee, which are continued far on to the immovable finger. The fingers are slender and
much incurved at the tips; they are provided with a lar
of irregular length.

ge number of closely set teeth

The Palps are slender and five-jointed. The first joint is quite small, the second
is the largest of all, and rather sparingly provided with sete, which are longest on
its outer side ; the third joint is a little shorter, slightly enlarged distally, the sete
being more numerous and more uniform than on the preceding joint. Of the two
terminal joints the distal one is a little the shorter, but together they exceed the
length of the second by a trifle. These two joints are richly setose, particularly on
one side,

The Oviger is ten-jointed ; in the female the first three joints are very small, but
progressively increase in length. The fourth and fifth are subequal and much the
longer of the whole series, and slightly curved in opposite directions. The sixth joint
is about three-quarters the length of the fifth. Of the four terminal joints the first
three progressively shorten, the terminal one being a trifle longer than the preceding,
and it bears a long slender pectinate claw with eight teeth. The first four joimts bear
scarcely any setz, except an inconspicuous distal fringe; on the fifth the sete are
noticeable on its outer border, and those of the distal fringe are rather long and
slender. In this particular the sixth joint is similar. The four terminal joints are
all provided with a distal fringe and a number of long sete. The denticulate spines
are arranged as usual in a single row, and, counting the joints from the base of the
appendage, they bear respectively 9: 7: 5: 7 of these spines (Plate X, fig. 15). These
numbers are not, however, rigidly adhered to. The spines consist of flattened shafts of
a slightly sinuous form, bearing four well-developed teeth on each side, with traces of a
fifth in large and uninjured specimens. The third tooth from the base is usually the
Q 2

34 T. V. HODGSON.

largest. In the fully developed male the fifth and sixth joints are remarkably swollen.
The enlargement of the fifth joint affects the distal half. The eggs are large, and the
spherical masses may be two in number on each limb; they are carried round the
fourth joint.

The Leg extends to a length of 21mm. These appendages do not differ
appreciably in size. Of the three coxee the second is much the longest, but not
so long as the other two together. The proportions of the three following joints are as
4:5:4°5. The tarsus and propodus together are as long as the femur, the former joint
being the longer of the two. The terminal claw is well developed, and is accompanied
by two very minute auxiliaries, not one, as stated in the ‘Southern Cross’ Collection,
Crustacea, p. 258. The entire limb is setose throughout, the setee abundant, and
variable in size, some of them distinctly spinous. For the most part their arrangement
is irregular, but on the second tibia a linear arrangement begins to be perceptible,
and this is clear on the tarsus and propodus, where the setee are much finer. The
distal fringe of the first coxa is dorsal, and not so strongly developed as on the
two following joints, more especially the third, where it is ventral. On the femur it is
chiefly dorsal, and the setze composing it are long and stout. On the first tibia
it is complete and rather spinous ventrally; this is more strongly developed on
the second tibia, where there is at least one powerful spine ventrally, and generally
two on each side. The male differs from the female in being more setose, the
setee being longer, more irregular, but scarcely, if any, stronger. The distal fringe
of the third coxa is particularly noticeable for the great length of the sete
composing it.

The Genital apertures of the female are conspicuous on the second coxa of all the
legs; those of the male are much smaller, and can only be detected on the two
posterior legs.

This species was taken in considerable numbers off Cape Adare, but inside
Robertson Bay, ih 20-26 fm. None were taken by the ‘ Discovery.’ I have re-
described it here to remove certain defects of the original description, and on account
of the capture of a form which, after considerable hesitation, I feel compelled to regard
as only a variety. his species is closely allied to NV. brevicaudatum Miers, with which
N. horridum Bohm has been identified by subsequent investigators. NV. brevicaudatum
Miers, can be readily distinguished from J. australe by the following characters :—

The trunk is more setose.

The tarsus is shorter than the propodus.

The terminal claw has two distinct, if small, auxiliaries.

The oviger bears a very much smaller series of denticulate spines, but their lateral

teeth are more numerous.

Tam unable to regard the Chetonymphon altioculatum of Mobius as a distinct
species, several examples of which were taken in the vicinity of Bouvet Island during
the ‘ Valdivia’ expedition.

PYCNOGONIDA. 35

CHATONYMPHON AUSTRALE, Ud/’. AUSTRINORUM.
(Plate IV., fig. 4; Plate X., fig. 15.)

Although no specimens of Chetonymphon australe were taken by the ‘ Discovery,’
yet a large number of individuals of a closely allied species were taken in Winter
Quarters, chiefly at the beginning of our stay there, before the ship was frozen in, and
while dredging was still possible within the 20-fathom line.

At first sight these specimens seem to be a distinct species; they are half as large
again or more, and their setose covering is finer. The intervals between the lateral
processes are much greater, and this is the only character of importance that separates
them. Another feature of doubtful value lies in the fact that the tarsus and propodus
together are distinctly shorter than the femur. In C. australe these two joints are as
long as the femur, or very little shorter, but the slight variation that occurs prevents
the acceptance of this fact as a reliable specific character.

The setose covering has already been alluded to as finer; it is so, but subject to
considerable variation both as to quality and quantity. In average specimens there are
large spinous sete on the tibiz, especially on the second. These are, for the most
part, arranged in a line but not very distinctly. Two dorsal rows, and a lateral row
each side can be distinguished, these are most prominent on the second tibia. There
may also be a mid-ventral row of very small spinous setze, rather closely set. Both
in C. australe and the specimens from Winter Quarters the ventral sete of the
femora and the two tibiz are much less conspicuous than elsewhere. In many indi-
viduals there is a conspicuous mid-ventral row of setze on the tarsus; these are closely
set and about as long as the diameter of the joint.

Two specimens were taken in 100fm. off Coulman Island ; of these one is com-
paratively small. The Ocular tubercle is rather more conspicuously flattened and very
slightly constricted below the eyes. The sete are as in the Winter Quarters
specimens, but without the spmous rows which, as before noted, are not always obvious.
Two other specimens were taken off the Barrier in 300fm. Lat. 78° 25’ 40" S.,
long. 185° 39’ 6” E. These are both males, one with young. In these the Ocular
tubercle is flattened, as in the Coulman Island specimens, and the terminal claw of the
leg is rather longer and more slender. The setose covering of the legs is very much
finer, but its arrangement is exactly the same.

It is quite impossible to find a distinct character by which these specimens can he
separated from C. australe, therefore I feel compelled to regard them as a variety only,
and a more southern form of that species. Some comparative measurements are given
below.

C. australe. C. australe, var. austrinorum.
W. Q. Coulman. 3arrier.
Length of entire body . : 5 . 8mm. 11 7 12 12
Length of body . ; : . 6mm. 8 D5 95 od

5
‘

Length of trunk, to insertion of abdomen 4*5mm. 6 4 7

36 T. V. HODGSON.

C. australe. C. australe, var. austrinorum.
W. Q. Coulman. Barrier.
Length of abdomen. : . 15mm. 2 15 25 2°5
Width of trunk . : : . 3mm. 4 3 scarcely 5 scarcely 5
Length of thirdleg. : F » 2imm, 31 1185 32 37
Proportions of femur and two tibix a) 4e 1dn 225 6 775 7 Gow a 7 8) oS
35 450 4

Tarsus and propodus together : . As long as femur, Shorter than femur

or very nearly.

In all cases the tarsus is longer than the propodus.

The Palps are alike in all cases, but these have not been accurately measured, as
this cannot be done without removal.

Fig. 4a is that of a Winter Quarters specimen.

The Ovigers are essentially alike, the differences between one or two of the joints
being very trivial (fig. 4b). The number of denticulate spines is too irregular to be of
any value.

PO as Omen de Po oer ee Cilio is 705 0).

The character of these spines is Shown in Plate X., fig. 15.

The sexual difference in these organs is the same in all, and the ova, which are
known in all but the Barrier specimens, are large and attached to the oviger in precisely
the same way.

PENTANYMPHON.

Body smooth, very slender, with lateral processes widely separated. Five pairs
of legs. Chelifori well developed, chelate ; scape a single jomt. Palps five-jointed.

Ovigers ten-jointed, terminating in a pectinate claw, the last four joints with
a single row of denticulate spines.

But for the additional pair of legs it would be quite impossible to separate
this genus from Nymphon. Only a single species is for the present recognised,
and this appears to have a circumpolar distribution. It has been taken by the
Scotch, German, and French Expeditions.

PENTANYMPHON ANTARCTICUM.

(Plate V.)

Pentanymphon antarcticum, Hodgson (11), p. 458; Cole (7), p. 405; Bouvier (3), p. 294.
Specific characters :—
Body very slender, lateral processes long and widely separated, neck very long.
Chelifori : chelw long and slender, shorter than scape, with short, stout, uniform, close-set teeth.
Palps : terminal joint longer than preceding, which is in turn half the length of the third.
Ovigers : terminal claw pectinate, denticulate spines, with seven pairs of lateral teeth, the first
being very small.
Legs rather long and slender, with a well-developed terminal claw and two auxiliaries; sete
arranged in four rows on the last three joints.

PYCNOGONIDA. 37

The body is very slender, quite smooth, with very widely separated lone lateral
processes. Anteriorly it is slightly curved downwards.

The Cephalon is long and slender, longer than the second and third segments, and
expanded distally into two dorsal lobes for the articulation of the chelifori.

The Ocular tubercle lies immediately in front of the first pair of lateral processes.
It is short, merely a low rounded hump, in fact, bearing four well-developed eyes.

The Abdomen is very small, directed upwards, and not separated from the trunk
by an articulation. It is rather conical and extends but little beyond the trunk, not
nearly so far as the posterior lateral processes.

The segmentation of the trunk is distinct, the joints occurring immediately behind
the lateral processes. i

The Proboscis is directed downwards, cylindrical, with a slight swelling about
the middle of its length ; it is as long as the cephalon, and its extremity is rounded.

The Chelifori arise above the proboscis, each on a lobe of the cephalon, which is
here rather more than twice its diameter posteriorly. The scape is single-jointed,
longer than either the proboscis or the chela. A few delicate sete are scattered along
its length, and there is an inconspicuous distal fringe. The chela is a little shorter,
the palm and dactyli occupying equal halves; the former is covered with fie setz
which also form a fringe round the base of the movable finger. The fingers are slender
and much curved near the tips. Both are provided with a row of fairly stout teeth of
nearly uniform size, rather closely set.

The Palps arise below the chelifori and at the sides of the proboscis ; they are
built on exactly the same plan as in the genus Nymphon (fig. 1a). The first joint
is small and stout, the proportions of the remainder being 8:5:3:4. The second
joint is sparingly setose except for a distal fringe; the other joints become more
and more setose to the last, which is richly supplied. On the outer side they are more
abundant than elsewhere.

The Ovigers are ten-jointed and present in both sexes. (Fig. 1b.) They arise
from very short but conspicuous processes on the lower side of the cephalon,
immediately in front of the first pair of lateral processes. The details of this
appendage are as in Nymphon. The first joint is very small, the second is twice the
size, and the third, which has a very oblique termination, is a little longer still ; none
of these bear sete. The fourth joint is very long, slender, and slightly curved; it
carries a glandular aperture on its outer side about a quarter of its length; all the
setze are small; very few occur except as a distal fringe. The fifth joint is longer still,
the longest of the appendage, and its distal half is enlarged in diameter ; it is covered
throughout with fine sete. The sixth joint is rather more than half the length of
the fifth, slightly curved, and on the outer side of the curve plentifully supplied
with fine sete. Of the four terminal joints the first is little more than half the
length of the preceding, the other three are shorter and sub-equal; very few sete
oceur, except distally. They carry a single row of denticulate spines (fig. 1c). These

38 T. V. HODGSON.

spines consist of a slender shaft with a swollen base; near the base is a pair of
small teeth followed by two pairs of comparatively long slender ones ; the remaining
four pairs are more slender and blade-like, graduating to a mere trace. The terminal
claw is furnished with about nine slender teeth. Both denticulate spines and
terminal claw are frequently very much worn.

With regard to the Legs, all five are practically of the same size and proportions,
and though there is a considerable amount of variation in this respect it is confined to
narrow limits. They may attain a length of as much as 36mm. Of the three coxee, the
first and third are sub-equal and together about as long as the second ; all, especially
the third, bear a few minute sete, chiefly ventral. The proportions of the three
following joints are approximately as 6°5:7 and 10; the tarsus and propodus are long
and slender, the former being the longer. The limb is more or less covered with fine
sete. On the femur they are scanty and for the most part small; a few longer ones
are to be found along the shaft and distally. On the first tibia they are comparatively
long and arranged in four indistinct rows, of which the lateral ones are not easy
to observe. On the second tibia they become smaller and much more numerous,
especially distally, and the distal fringe is strongly developed ventrally. The same
arrangement holds good for the two remaining joints, but the ventral row is very
strongly developed, the setee becoming almost spinous and closely set. The terminal
claw is a powerful one, and is accompanied by two slender auxiliaries of about quarter
its size.

The Genital apertures of the female are found on the second cox of all the legs
and in the adult they are distinct enough. The apertures of the male are at all times
difficult to observe, and I have only been able to distinguish them on the three posterior
pairs of legs. :

Nearly thirty specimens of this species were taken in Winter Quarters, at all times
of the year, and in depths ranging from 12 to 125 fathoms. They vary considerably
in size, a variation obviously due to age, but in essential details they are in agreement
except in one particular, and that is the articulation of the abdomen to the trunk; in
certain cases among the more robust forms it is distinctly articulated. The trunk in
all cases is seen to be very minutely scabrous when removed from spirit. The females
are more robust than the males when the sexes can be separated, a feature which is
most noticeable in the femora, but extends to the first tibiae. The males, as a rule, are
rather more setose than the females.

A few of the eggs borne by one of the males are hatched. On emerging from the
eve the body is ovoid, and possesses three pairs of appendages. The cheliforus
comprises a stout scape with one very long seta, and a small but well-developed chela,
without teeth on the dactyli; a small proboscis lies below these. Details of the other
two pairs of appendages cannot be seen without special preparation, which has not as
yet been undertaken. Other specimens crawling about the egg-masses show the
proboscis, chelifori, the palps not clearly jointed, and four pairs of appendages, having

PYCNOGONIDA. 39

three stout sub-equal joints, followed by a fourth nearly as long as the three together,
only a great deal more slender, and terminating in a very minute claw; a conical
abdomen lies at the extremity of the trunk, the posterior part of which is provided
with a small number of very long sete.

LEIONYMPHON.

Prof. Mobius (23) has described this genus as follows :—

“ Korper kurzhaarig. Rumpf breit. Beintriiger am Grunde zusammenstossend. Hals kurz und
breit. Augenhtigel konisch mit 4 Augen. Riissel walzenformig. Finger ohne Zihne. Palpen
neungliedrig. Brutbeine zehngliedrig, 7. Glied beim Minnchen kurz und dick ; alle Glieder nur kurz
behaart.”

LEIONYMPHON, 7.9.*

Rumpf ebenso breit wie lang. Die beintragenden Seitenforsiitze der Rumpfglieder stossen
zusammen. Kopfsegment breit. Augentriiger konisch.

Riissel walzenférmig. Scheren kurzer als der Riissel. Finger ohne Zihne. Palpen neungliedrig.

Brutbeine zehngliedrig ohne eigentiimlich geformte Dornen oder Ziihne an den 4 letzen Gliedern.
An den minnlichen Brutbeinen ist das 7. Glied sehr kurz, aber viel dicker als die andern 3 Endglieder.

This genus was established for the reception of a remarkably fine species, L.
striatum (Mébius), of which however only two examples were taken, and both of them
immature. A species in the same collection described by Prof. Mobius as Colossendeis
gibbosa appeared to me to be closely related, and an examination of the two species
which I have been permitted to make fully confirmed this suspicion. The ‘ Discovery ’
has brought from the Antarctic several species which are unquestionably very closely
related. The ‘ Francais’ (2) has also found two-species. Two more were described
some years ago by Dr. Pfeffer (24), from South Georgia, and placed by him in the genus
Ammothea.

That the genus Leionymphon is very closely related to Ammothea is beyond all
question. To this latter genus not less than thirty species have been ascribed, but
many of them present such peculiar characters that they cannot fairly be included. It
is not possible here to revise the genus, but I have considered it desirable to modify
Prof. Mébius’ definition of the genus Leionymphon, and to give a list of those species
which I consider should be included therein.

LEIONYMPHON.

Body more or less robust, with transverse ridges developed to a greater or less extent. The
lateral processes widely separated or otherwise ; spurs rather than spines, or traces of them, occur on
the lateral processes and first coxze.

The Proboscis is large, cylindrical or pyriform.

The Palps are nine-jointed, the last five joints being short.

* “Yeios glatt. Die 4 letzten Glieder der Brutbeine sind nicht mit eigentiimlich geformten Ziihnen oder
Dornen besetzt.”’

VOL. II, R

40 T. V. HODGSON.

The Oviger is ten-jointed, without a terminal claw, the last four joints with an irregular series of
special spines. In the male, the seventh joint bears a tuft of setee, and the eighth and ninth joints are
articulated at a considerable angle to the preceding joints.

The Legs are long, tarsus very small, propodus armed proximally on the ventral margin with a
series of stout spines, claw rather large, and accompanied by two well-developed auxiliaries.

The “Genital apertures occur in the male on the two posterior pairs of legs; in the female on
all the legs.

The species I would assign to this genus are :—

L. striatum, Mobius, 1902.

L. grande, Pfeffer, 1889 = Ammothea grandis, Pfeffer.

= Ammothea charcoti, Bouvier.

L. gibbosum, Mobius, 1902 = Colossendeis gibbosa, Mobius.

L. minus, sp. NOV.

L. clausti, Pfeffer, 1889 = Ammothea clausti, Pfeffer.

L. australe, sp. nov.

L. ylaciale, sp. nov.

LL. spinosum, sp. nov.

T have hesitated for some time as to the position of Ammothea magniceps (Thomson)
from New Zealand (30). Mr. G. M. Thomson most kindly placed the whole of his
collection at my disposal, but unfortunately it does not contain an adult male of this
species, therefore the structure of the male oviger remains unknown. The transverse
ridges of the trunk are prominent, but there is no trace whatever of the spurs so
characteristic of Leionymphon. Under any cireumstances, the species cannot be
regarded as a true Amimothea. (Mr. Thomson is in error in describing the palp as
with ten joints, there are only nine.) Be the true position of this species as it may, it
exhibits a preliminary stage in the transition between the diminutive Ammothea and
the large Leionymphon. The next step is indicated by ZL. clausii and L. australe ;
these two species are very much alike; from these by LZ. minor, L. gibbosum, and
L. grandis to L. striatum. It would be difficult to give L. glacialis and L. spinosum a
position in a linear series. They probably diverge from L. striatum in a different
direction to the others.

KEY TO THE SPECIES.

Body traversed by three prominent pyramidal ridges, spinose or setose :—
Lateral processes close together—
*Proboscis half as long as body, cylindrical. Z. striatum.
Proboscis little longer than body, cylindrical. LZ. grande.
*Proboscis as long as body, conical. ZL. gibbosum.
Proboscis shorter than body, slender, pyriform. Z. minus.
Lateral processes widely separated —
Proboscis little shorter than body. Z. ylaciale.
Proboscis short, not half length of body. LZ. spinosum.
Body traversed by three rounded ridges, smooth :—
Abdomen vertical, base traversed by the last trunk articulation. Z. clausiv.
Abdomen oblique, some distance behind the last trunk articulation. L. australe.

* Known only from immature examples.

PYCNOGONIDA. 4]

LEIONYMPHON GRANDE.

(Plate VL, fig. 1.)
Aminothea grandis, Pfeffer (24), p. 43.
Ammothea charcoti, Bouvier (2), p. 295.

Specific characters :—
Body robust, with three prominent transverse ridges dorsally and ventrally.
Proboscis cylindrical, very little longer than the body.
Palp 9-jointed, the last joint a little longer than any of the four preceding ones.
Oviger 10-jointed, without a terminal claw, the last four joints with simple curved spines, which
increase in size to the extremity of the last joint.

The body is stout, and with the abdomen, scarcely as long as the proboscis,
being just less than 15mm. — Its width across the second pair of lateral processes is
10mm. Its segmentation is complete, but concealed by a very strongly developed
pyramidal ridge which les along the posterior margin of the three anterior segments,
and the apex of which is raised considerably above the body level. These ridges have
a very slight curvature forwards, which is most marked in the first. The lateral
processes are not widely separated, the two anterior pairs are directed forwards, the
first more than the other, and are quite close together; the third pair is directed
backwards slightly with a wider interval between it and the preceding pair; the last
pair is directed backwards at such an angle as to make the interval between the third
and fourth pair very conspicuous. All have a swelling at the distal extremity, and
this swelling gives the process an angular appearance.

The Cephalon is short, expanded anteriorly, and at the base of the chelifori presents
the same angular appearance as the lateral processes. A slight median groove divides
its anterior margin.

The Ocular tubercle lies in the middle ; it is stout, with a very slight curvature,
rounded at the apex, and bearing four well-developed eyes.

The Abdomen rises from the extremity of the trunk, but without trace of
segmentation ; it is rather stout, slightly curved, and directed upwards. There is a
median tubercle between the posterior transverse ridge and the abdomen. Dorsally
the entire body is rendered scabrous by the presence of small spinous sete ; between
the body ridges however they are scarce. Ventrally the three transverse ridges of the
dorsum are represented by three similar ridges, thinner and not produced to such a
conspicuous point; all are directed backwards to a varying degree, the first more so
than the others. These ridges are continued on to the base of the lateral processes,
which here do not present any trace of the angular enlargements so conspicuous
dorsally. The spinous setze of the dorsum are not present.

The Proboscis is stout and cylindrical, only a trifle longer than the body and
abdomen together. It is articulated to the body, and movable through a very
considerable angle. The mouth is large and triangular. The distal extremity of the
organ is deeply pigmented; for nearly three-quarters of its length it displays six

Ree

42 T. V. HODGSON.

bands of a dark yellowish-brown colour ; it then abruptly changes colour, and tapers
a little to its junction with the body.

The Chelifori are rudimentary, and arise from the cephalon dorsal to the proboscis,
and rather in advance of its origin. The scape is short and stout, slightly curved, and
with the distal extremity oblique. Articulated to it is a mere knob which bears at its
extremity a minute tubercle in a distinct socket, and on its outer border a small
spine. The entire appendage is covered with minute spinous sete.

The Palps are nine-jointed, and arise from the cephalon immediately below and
external to the chelifori. The first joint is small, and the second is very nearly four
times as long, the third is again small, and the fourth nearly twice as long as the
second. The remaining five joints are together but little longer than the fourth,
and differ but little in size; the terminal one, however, is the longest of this series.
The entire appendage is covered rather irregularly with the characteristic small
spmous sete of the animal. They are not numerous on the proximal four joints,
but on the remaining five they are rather longer and finer, as well as being a little
more abundant.

The Ovigers are ten-jointed, and arise ventrally at the angles formed by the first
pair of lateral processes and the body. All the joints are small, the second and
fourth being a little the longest (fig. la). The first jot is very small but stout, the
second and fourth are the longest and sub-equal, the third is shorter and slightly
curved. From the fourth the three following joints progressively decrease a little in
length, the first three forming a curve in the natural position of the appendage. All
these joints are stout, the three terminal ones becoming more and more slender; the
eighth joint, though more slender, has the same character as the preceding, the ninth
is a little shorter, and the last one is the longest of the four terminals. The entire
limb is covered, but not thickly, with small sete ; they are most numerous on the
fourth, fifth, and sixth joints, on the latter of which they are conspicuous only on the
outer side of its curvature. The remaining four joints form a curve in a contrary
direction, and on the inner side of this curve is a row of stout curved setee, Increasing
in size and strength to the end of the terminal joint, where they form a conspicuous
group. These spines are quite simple, and the last joint does not bear a claw, though
it seems adapted for one.

The Legs are stout but not of any excessive length, being something like 62mm.
The second coxa is fully as long as the other two together, and the proportions of the
remaining joints are as—15:13:17:1:5. The first coxa is marked with a median
dorsal and ventral line which separates the muscles moving the succeeding joint, the
distal margin is tuberculated dorsally like the lateral processes, but only to a very
slight extent ; the second coxa is conspicuously wider in diameter at its distal than at
its proximal extremity. All three are covered with very small but stout sete. The
femur is a stout joint, its distal extremity being raised dorsally into a slight angular
ridge ; the entire jot is covered with the characteristic setee with the exception of a

PYCNOGONIDA. 43

lateral band of some width, almost completely bare of them. On the two tibize the
same arrangement of the sets occurs, except that along the middle of the bare band
there is a narrow band of sete two or three wide. The distal fringes of the femur and
first tibia are not conspicuous, but that of the second tibia is formed of stout spines
chiefly on the ventral surface. The tarsus is a very small joint, and forms a cup-like
socket for the propodus (fig. 1b); it is thickly covered with small spines, and its distal
fringe is well developed, especially ventrally, where it is formed of very stout spines.
The propodus is covered thickly with stout setee with only an irregular vestige of the
bare band found on other joints; it is slightly curved, and its ventral side bears
proximally four or more very stout spines, of which the first is the smallest; the rest
of the margin is taken up with setz small, but larger than the average ; close to the
terminal claw is a group of large sete, one of which at least is a rather prominent
spine. The extremity of the joit is oblique, and forms a rounded spinose projection
or heel beyond the origin of the stout claw, which, with its two powerful auxiliaries,
arise from a common investment.

The single adult specimen captured is a female, and the Genital apertures are
conspicuous on the second coxa of each leg. Five smaller specimens were, however,
taken at the same time and place, varying in size from 9°5 mm. to 18°5 mm. over all.
These present several differences of no small importance. The proboscis differs slightly
in form, being more tapering the smaller the specimen, and it is also more rigidly
articulated to the body ; in none of them is it movable through so large an angle as
in the adult. The chelifori are proportionally the same size as in the adult, but a
perfect chela is developed. This is small and feeble, the fingers curved like a pair
of callipers, and devoid of teeth. On the body the dorsal ridges are raised into a
more definite median point, and the tubercles which give an angular appearance to the
lateral processes and first coxee of the adult are now rather more prominent and carried
on to other joints. The pre-abdominal tubercle is a very variable structure, and is
sometimes prominent—in one case almost absent. The palps do not call for any fresh
description, but the ovigers show several interesting stages in their development (figs.
1c-1f). In the smallest specimen only the merest vestige of such an appendage exists.
In the next specimen four joints as such may be distinguished, the last one showing an
indication of future segmentation. In another, six joints are fairly well established,
the penultimate one showing traces of another division. In the largest of the
immature specimens the oviger possesses the full number of ten joints, but they are
very small, and the four terminal ones are only indicated and not clearly developed.

Cape Wadworth, Coulman Island, 8-15 fathoms. Bottom: stones. Several
adult specimens were taken by the ‘Frangais’ off the west coast of Graham’s Land,
and one was taken by the ‘ Scotia.” The examination of Professor Pfetfer’s Anumothea
grandis trom South Georgia has established the identity of this species beyond all
question.

44 T. V. HODGSON.

LEIONYMPHON MINUS.

(Plate VI., fig. 2.)
Specific characters :—

Body rather robust, with three prominent transverse ridges produced to a point in the mid-
dorsal line.

Proboscis shorter than the body, slender, pyriform.

Palp 9-jointed ; the terminal joint twice as long as any of the preceding four.

Oviger 10-jointed. In the male the three terminal joints bear an irregular series of stout but
simple spines. No terminal claws.

The body is rather robust and the lateral processes are clearly but not very widely
separated. It measures rather less than 5 mm. in length and less than 4 mm. in
extreme width. The segmentation is distinct, and the articulations le at the hinder
part of the three transverse ridges which cross the body. These ridges are strongly
developed, produced to a point in the middle line, and slightly curved backwards. They
are equally prominent ventrally, but inflected backwards and not produced into a
point. The lateral processes are stout, the two anterior being directed forwards at
slightly different angles, the two posterior ones are similarly directed backwards ; each
bears dorsally two distinct tubercular processes which are also to be found in a less
prominent degree on the first coxee.

The Cephalon is scarcely, if at all, expanded, and its centre is occupied by a very
stout Ocular tubercle which is directed slightly forwards, and appearing, in certain
aspects, to be enlarged near its extremity, which bears a very rudimentary spine. The
four eyes are not particularly well developed.

The Abdomen is short and stout, not separated from the trunk by an articulation ;
it is directed obliquely upwards and does not extend as far backwards as the last pair
of lateral processes.

The Proboscis is pyriform, slender, and about two-thirds the length of the body,
to which it is flexibly united. It shows indistinctly three pairs of longitudinal bands
along the greater part of its length.

The Chelifori are rudimentary ; the scape is well developed, slightly curved, and
bears only a few small setze besides the rather promiment distal fringe. The chelze are
reduced to a knob with the merest traces of fingers.

The Palps are 9-jointed and rise at the side of the proboscis; the first and third
joints are quite short and subequal, the second and fourth are also subequal and about
five times as long; the four following are quite short and subequal, while the terminal
one is ovoid and twice as long as any of the preceding four. The fourth jomt bears a
small distal fringe, but otherwise there are practically no setz on the first four joints ;
the following four joints are very considerably dilated ventrally, and this enlargement
bears a dense tuft of small stiff sete. The terminal joint is more extensively covered
with sete, especially on its ventral side.

The Ovigers are 10-jointed and rise ventrally just in Row of the first lateral

PYCNOGONIDA. 45

process (fig. 2a). The first joint is small and stout, the second is more than twice
as long, stout and enlarged distally, the third is scarcely as long and has an oblique
termination. These three joints form a curve in one direction, and the three following
form a similar curve in another. The fourth and fifth joints are long and subequal,
the sixth being about half the length of either; its termination is rounded, the
following joint being articulated at the side. All these joints are more or less
plentifully setose ; the sete are very small, but their structure and arrangement call
for no comment. The seventh and succeeding joints progressively decrease in leneth
and stoutness as far as can be made out from the angle at which they lie, and they
are all small. The seventh lies at right angles to the sixth, and near its distal and
inner side it bears a dense tuft of long sete. The eighth joint is articulated at
the side of the seventh and at right angles to it; it also bears a small tuft of long
setze near its distal extremity but on its outer side; the following joint is similarly
provided, but with fewer. The last three joints bear an irregular series, not a single
row, of stout spines (fig. 2c); most of them occur on the terminal joint, but there are
scarcely a dozen altogether. There is no terminal claw.

The Oviger of the female is essentially different to this (fig. 2b). All the joints
are smaller, the third conspicuously smaller than the preceding, and the fourth, though
the longest of the appendage, is still quite short, and the remainder gradually and
progressively decrease in length. Up to the sixth the joints remain stout, the rest are
much more slender, and there is nothing noteworthy in their articulation, which is
quite normal. The sixth joint is thickly covered on its outer side with minute sete,
and up to this joint the sete have been increasing in number. The terminal joint is
unfortunately missing in the specimen examined, but the three preceding are almost
devoid of any setze at all.

The Legs measure about 28 mm. in length. The second coxa is scarcely the length

ld

of the other two together, the femur measures some 7 mm., the first tibia is the merest

trifle shorter, the second a little longer, 7°5 mm., the tarsus and propodus together are
about one-third the length of the second tibia. .The second coxa bears a small but
distinct tubercular enlargement just beyond the middle of its length dorsally, and in
the male there is a similar tubercle dorsally near the extremity of the femur, with
a glandular aperture upon it. The entire limb is setose, but the sets: are very small ;
no definite arrangement can be seen as far as the first tibia, up to this joint they are
not numerous and only visible with difficulty. On the tibiee they become numerous; on
the first their arrangement is indistinct, on the second it is more readily made out, and
consists of a dorsal and a ventral band of sete with another narrow band passing along
the centre of a bare space laterally. The distal fringes are but poorly developed, the
most conspicuous one being on the second tibia and chiefly ventral. The tarsus is a
very small cuplike jomt, densely setose on its longer and ventral margin. The propodus
is slightly curved and dorsally projects considerably beyond the insertion of the large
terminal claw and its strong auxiliaries. The joint is thickly covered with stout

46 T. V. HODGSON.

setee on its ventral surface, and proximally there is a row of some four to six very
strong spines; dorsally the setz are similar, but not so thickly distributed nor so
strong; laterally also they occur, and there appears to be a narrow hand devoid of
sete, but this is not distinct. The terminal claw and its auxiliaries arise from a process
on the ventral side of the prolongation alluded to above.

The type of this species is an adult male bearing eggs, taken in Winter Quarters at
a depth of 125 fm., 9 Feb., 1903. Another was found at a depth of 35 fm., 5 March,
1903. The ova are small and are carried in a large, rather irregular mass round the
fourth and fifth joints of the oviger. The Genital apertures occur ventrally at the distal
extremity of the second coxa of the two posterior legs. They are large, with tumid
lips. Genital apertures of the female are on all the legs. A male and a female were
also taken off Cape Wadworth, Coulman Island, in 8-15 fm., 15 Jan., 1902. These
are smaller than the type.

LEIONYMPHON AUSTRALE.

(Plate VIL., fig. 1.)

Specific characters :—

Body robust, with three low rounded transverse ridges; these ridges are more prominent
ventrally. Abdomen directed obliquely upwards, and well behind posterior trunk articulation.

Proboscis pyriform, little shorter than the body.

Palp 9-jointed, the seventh and ninth being a little the longest of the five terminal joints.

Oviger 10-jointed, without a terminal claw, the last four joints with an irregular series of

denticulate spines.

The body is robust and, without taking the lateral processes into consideration,
broadest about the third process, from which it gradually narrows forwards.

The Cephalon is but slightly expanded and the neck is not distinct. The entire
body measures 9 mm. in length, of which 4 mm. are taken up by the proboscis ; the
Abdomen does not enter into consideration, as in its natural position it is carried
obliquely upwards, and does not extend beyond the last pair of lateral processes ; it
is,. however, 1§ mm. long. Segmentation is distinct, except so far as regards the
abdomen, and occurs on a low ridge which crosses the body immediately behind the
lateral processes. These ridges also occur ventrally and, being reflected backwards,
give to each segment the appearance of being socketed into a recess. The lateral
processes are not widely separated, but the intervals increase slightly from before,
backwards; all are provided at their distal extremities with two small spur-like
processes ; these are dorsal.

The Ocular tubercle is stout, moderately tall, rounded at the apex, and bears four
well-developed eyes.

The Proboscis is movably articulated to the body and pyriform in shape, its
diameter increases for more than a third of its length, and then enlarges abruptly,
and is marked by three double bands, presumably muscle bands, transversely divided
near the tip. The mouth is triangular, not large, but with thick lips.

PYCNOGONIDA. 47

The Chelifori are rudimentary and comprise a stout scape of one joint, which
is slightly curved; except for a distal fringe which is not conspicuous, the joint
is not setose. The chele in the adult are only represented by knobs, and these
show the merest traces of two fingers. In younger specimens the chelew are developed
and exhibit comparatively long curved fingers devoid of teeth.

The Palps are nine-jointed and arise at the side of the proboscis. The first joint
is short and stout, the proportions of the three following are as 5 : 1: 4; the remaining
five are all short and differ little in size, the first and third are sub-equal, the
second and terminal are very little shorter but also sub-equal, the penultimate is the
shortest; the last jot is ovoid in shape, setose throughout, the sete more thickly
distributed on its inner margin. The other four joints have slender bases and are
much enlarged and densely setose on the inner margin ; the outer margin is straight
and bears a distal fringe. The preceding joints are also more or less setose, the short
setee beginning near the distal extremity of the second joint and becoming fairly
numerous on the fourth.

The Ovigers are ten-jointed and arise ventro-laterally immediately in front
of the first pair of lateral processes; they differ in the two sexes. In the male
(fig. 1a), the first joint is small and stout, and the proportions of the five following
are as 4:2°3:4:4:2; the first of these, second of the appendage, is slightly
curved; the next is less so, but with the three following forms a large curve,
the fifth joint being the only one that is distinctly curved itself. All these
jomts are setose, particularly on the outer side of the curvatures. The four
remaining joints are short ; the seventh is articulated at the end of the sixth, but
at the side, and makes nearly a right angle with it; near its distal extremity
it is provided with a dense tuft of long sete. The eighth joint is similarly
articulated to the seventh, but in the opposite direction, and bears a smaller
tuft of long sete distally; the ninth is the shortest joint. The three terminal
joints bear a small number, less than a dozen, of denticulate spines, most of
which occur on the terminal joint. They are. not in a single row, and consist
of a slender shaft with seven closely-set flat teeth on each side.

The oviger of the female is quite different and the articulation of its joints
is normal throughout (fig. 1b). The first and third joints are together equal to
the second; the fourth and fifth are sub-equal, and the longest on the appendage ;
the sixth and seventh are a little shorter and sub-equal, the eighth and tenth
are again shorter and sub-equal, and the ninth still shorter. Sete are scarce,
and the sixth joint is the only one that can be described as setose. The
denticulate spines occur on the four terminal joints, and are exactly like those
of the male, but much more numerous, there being upwards of a dozen on
each of the joints except the first of the series.

With regard to the Legs, the second coxa is scarcely as long as the other
two together; the proportions of the three following joimts are as 6°5:6:7°5;

VOL, Il. Ss

48 T. V. HODGSON.

these joints are subject to variation, but not of great moment, ‘5 mm. or there-
abouts; the tarsus is quite small and cup-shaped, the propodus rather more
than a quarter the length of the second tibia. The entire limb is covered with
short sete, but on the second tibia and the propodus there are longer ones
interspersed among them. Throughout the entire limb there is a broad lateral band
devoid of setae except for a narrow row of them along its centre; dorsally and ventrally
the sete are abundant, particularly towards the extremity of the limb. The distal
fringes are normal and inconspicuous, 7.¢., indistinct on the first coxa, ventral or
chiefly so on the other two, complete on the femur; on the two tibie they are
best developed ventrally, and become spinous, especially on the second; the tarsus
is covered with small spines or spinous sete ventrally, the propodus has a very
prominent heel and bears a_ stout claw with two well-developed auxiliaries
rather more than half its size. The heel bears numerous spinous sete, and at
the proximal end of the joint on its ventral margin there are some half-dozen
stout and prominent spines.

The Genital apertures occur on the second coxe of all the legs in the
female. but they can only be found on the two posterior legs of the male.
The ova are small and numerous and are carried in a spherical packet round
the fourth joint of the oviger.

Several specimens of this species were taken in Winter Quarters at depths
varying from 25 to 125 fms., the majority however coming from the latter
depth. The specimens vary in age and size, but the species may be regarded
as a variable one. While the general arrangement of the sete remains the same
it is not so clear in the young examples. In these the sete are for the most
part long and fine instead of short and comparatively stout; the transition
from the one form to the other is gradual, some of the adults retain a goodly
proportion of the long sete among the others. A very few minute sete may
be found on the ‘body in some individuals, especially on the abdomen. In most
individuals the summit of the ocular tubercle bears a very short spine instead
of being rounded. In the young the chele are fairly well developed, they are
of moderate size, the fingers being quite smooth and resembling a pair of callipers.
The spur-like tubercles on the lateral processes of the adult are, in the young,
very prominent spines and frequently bifurcated ; similar spines occur on the cephalon.
One specimen has the oviger not completely developed and in another the full
number of joints is not yet differentiated.

All the adults possess a glandular aperture of some kind on the dorsal
surface of the second coxa just beyond the middle of its length.

One individual has the second and third legs of the left side abnormally
developed, probably new growths in reparation of injury; one of these limbs
does not extend beyond the extremity of the first tibia, the other is longer.

This species very closely resembles L. clausi Pfeffer, but may be readily

PYCNOGONIDA. 49

distinguished by the fact that in that species the abdomen is directed almost
vertically upwards, and is situated so far forward that the posterior trunk sezment
passes over its base, a feature of, possibly, some morphological importance.

LEIONYMPHON SPINOSUM.
(Plate VIL., fig. 2.)

Specific characters :—

Body stoutly built, with the transverse ridges not very strongly developed, but with a very
prominent spur in the mid-dorsal line. The lateral processes are rather widely separated, and bear
distally two stout recurved spurs ; smaller ones exist on the first coxe.

Proboscis short, not half the length of the trunk.

Palps 9-jointed ; of the five terminals the seventh and ninth are a little longer than the others.

Oviger 10-jointed, special spines not denticulate.

The entire animal is heavily built, and covered with fine but short sete. The
lateral processes are rather widely separated, the intervals increasing posteriorly, two
pairs of processes are directed more or less forward, the other two pairs backward.
Each process bears dorsally at its distal extremity a pair of prominent recurved
tubercular processes ; these are also distinct, though less prominent, on the first coxe.
The body is crossed transversely by three ridges, but these do not extend on to the
lateral processes as much as in the allied species. These ridges stand erect, but they
are bevelled from behind in the middle line so as to form an acute point of some
considerable elevation, and this gives them the appearance of being arched forward.

The Cephalon is not very much expanded, and almost fills the interval between the
first pair of lateral processes ; in front it bears a pair of tubercular processes directed
outwards, one at the base of each of the chelifori.

The Ocular tubercle is just behind the centre of the cephalon and is very stout, taller
than any of the transverse ridges, and terminates in a cone above four well-developed eyes.

The Abdomen is not separated from the body by an articulation ; it is of normal
proportions, elongate, ovate and directed slightly upwards.

The entire body is covered with short, fine setee, but they appear to be deficient
between the ridges, and to some extent on the cephalon. Ventrally the transverse
ridges are rounded, and the median spur much less prominent than dorsally ; the sete
also are deficient. The length of the body is 13 mm., and its extreme width is 8 mm.

The Proboscis is short and stout, being barely 5 mm in length, cylindrical, slightly
swollen in the middle, and movably articulated to the body.

The Chelifori are rudimentary, they lie close together above the proboscis and are
more than half its length. The scape is half the length of the proboscis, very slightly
enlarged distally and clothed with short setee; the chelee are only knobs, also setose,
and with but vestiges of the fingers.

The Palps rise laterally below the chelifori and comprise nine joints (fig. 2a). The
first joint is short and stout, the proportions of the various joints being: 1°5:4:1:5°5:
1:1:1°3:1:1°5. The entire appendage is covered with fine setze which become numerous
on the fourth joint ; on the four following joints they form a dense patch covering the

S23

50 T. V. HODGSON.

whole ventral surface, and extending dorsally in a very small degree on the first of these
joints but progressively more and more as the extremity of the appendage is approached.
The terminal joint is completely covered, but they are most abundant ventrally.

The Ovigers are ten-jointed and rise ventrally in the angle formed by the cephalon
and the first lateral process (fig. 2b). The first six joints form the normal double
curve and are all more or less covered with small sete on the outer part of the
curvatures. The proportions of the various joints are : 1°5 :3°25:2:3:3:2:2:2:15:2.
The last four joints are provided with a few large spinous sete forming, on three
of the joints, a small irregular group ventrally near the distal extremity ; on the terminal
one, which is much the most slender, they are scattered along its length, one of them
taking the place of the terminal claw.

The Legs are not all the same size, the third pair being the longest and the first
the shortest, their respective lengths being approximately 30 mm., 35 mm., 39 mm.,
37°5 mm. The third lee of the right side has been measured. Of the three cox the
second is longer than either of the other two, the three together attain a length of
8 mm., and the proportions of the other joints are as 9°25: 9: 8 : 3°5, the last figure
representing the tarsus and propodus together. The entire appendage is densely
clothed with rather short but fine setze having no special arrangement, except that on the
femur and first tibia they are not so numerous laterally. The tarsus is small, cuplike,
densely setose, but with no strong spines. The propodus is slightly curved, densely
setose, and with an oblique termination to the jomt, but the process from which the
large terminal claw and its two moderate-sized auxiliaries arise projects beyond the joint
itself. The ventral margin of the propodus is spinose but varies greatly. In the best
instance there is a series of eight spines, the first four are small and then they increase
in size rapidly to the last, which is very large. These occupy the proximal half of the
joint. Then follows another series of six of nearly uniform size and not so large as
the biggest of the previous series. This second series occupies the remainder of the
joint and are disposed radially. In other cases the first series is not so well developed
and the second is deficient.

The single specimen of this species is an adult female, the Genital apertures are
found near the middle of the second coxee of all the legs.

Taken in 300 fathoms off the Barrier. Bottom: mud. January 27, 1902.

LEIONYMPHON GLACIALE.
(Plate VIL., fig. 3.)

Specific characters :—
Body well built, with three very prominent transverse ridges produced to a point in the mid-dorsal
line. Lateral processes rather widely separated, and with the stumps of spur-like processes distally.
Proboscis large, but shorter than the body, pyriform.
Palps 9-jointed, the five terminals being sub-equal in size.
Oviger 10-jointed (not mature).

This is a large and comparatively slender species.

PYCNOGONIDA. 51

The Body is well built with the lateral processes rather widely separated, and
traversed by three very prominent pyramidal ridges which conceal the segmentation.
These ridges are directed backwards to a very slight extent and excavated posteriorly ;
it is in the hollow thus formed that the segmental divisions may be seen. Three ridges
are equally prominent ventrally, but they are not produced to a median point. .

The Cephalon is not very much expanded, and a neck is not noticeable.

The Ocular tubercle is stout, not as tall as any of the three transverse ridges, and
bears four well-developed eyes, above which it terminates in a short cone.

The Abdomen is rather long, directed obliquely upwards, not separated from the
trunk by an articulation, and terminating in a blunt point. The cephalon bears a
small blunt tubercle at its anterior margin on the outer side of the base of the chelifori,
a pair of similar tubercles occur dorsally at the extremity of the lateral processes ;
smaller ones also on the first cox with traces of them on the second. The length of
the body is 12 mm., its extreme width is 7 mm. The entire body is scabrous, a feature
most distinctly noticeable on the transverse ridges and the abdomen.

The Proboscis is large, rather pyriform in shape, and measuring 10 mm. in
length. It is movably articulated to the body on a large base, and widens slowly for
one-third of its length where it is very slightly constricted; it is then enlarged
again, and tapering very slightly, ends in a rather broad round point, the triangular
mouth being of moderate dimensions. The proboscis is smooth, and its distal two-
thirds are marked by three pairs of longitudinal bands, transversely divided near
the tip.

The Chelifori are rudimentary and lie close together above the proboscis. The
scape is short, slightly curved and enlarged distally ; the chele are well developed,
as long as the scape, one half of their length is taken up by a bulbous palm; the
fingers are slender, quite smooth and much curved, but those of the two appendages
are not exactly alike. With the exception of the fingers the entire appendage is
scabrous.

The Palps arise laterally just outside the chelifori, and comprise nine joints
(fig. 3a). The first is short and stout, the proportions of the second and fourth are
as 8 to 11, the third being but little longer than the first; the remaining five are
short and sub-equal, the middle one and the last being a trifle the longest, together
they scarcely equal the length of the fourth. The fourth joint possesses a prominent
tubercle with a glandular opening at two-thirds of its length. The entire appendage
is more or less plentifully clothed with very minute spinous sete ; these however are
only conspicuous on the ventral margin of the five terminal joints and at the end of
the terminal one.

The Oviger is ten-jointed and rises ventrally immediately in front of the first
lateral process, and appears to be that of a female (fig. 3b). It is not fully developed.
The first joint is short and stout, the two following are twice as long and sub-equal,
the third having the usual oblique termination. These three joints form a natural

52 T. V. HODGSON.

curve in one direction, and the three following curve in another. Measured in their
extreme length the proportions of the various joints of the appendage are: 3:6:6:8:
7°75:7:4:4:2°5:4. The third and following joints are all more or less covered with
very short stout setee on the outer side of their curvature ; these setae are most con-
spicuous on the fourth, fifth, and sixth joints, on the last of which they are also lateral.
The last four joints each bear a small number of stout but simple spines, 4: 8 : 7 : 6, not
arranged in a single row. The last jomt tapers to a blunt point, and is without a
terminal claw, a small group of these spines taking its place.

The Legs attain a length of about 55 mm. Of the three coxee the second is twice
the length of the other two, the proportions of the remaining joints beg 13°5 : 12:
16:4, the last figure representing the tarsus and propodus together. The coxze are
densely clothed with very minute setz, but on the femur they are much larger,
though still small, and more conspicuous. They are arranged as a dorsal and a ventral
band, separated laterally by a considerable interval, along the centre of which is a
narrow band of similar sete. This arrangement is continued along the tibiz but it
is not so distinct on the second. The distal fringes are quite normal and incon-
spicuous. The tarsus is a very small cup-lke joint, covered with spinous setz
ventrally, with a few prominent ones distally. The propodus is uniformly covered
with small spinous sete, but ventrally there is a row of stout spines running
the whole length of the joint. These spines are very irregular; beginning from the
proximal end the first three or four rapidly increase to large dimensions, the rest are
very irregular in size, but none are so large as the last of the proximal series. The
joint terminates obliquely, the dorsal projection is not large; the terminal claw is
stout, and its two auxiliaries are quite half as long, arising together from a process of
the oblique termination.

The single specimen of this species is immature, and was taken in Winter Quarters
at a depth of 125 fathoms.

AUSTRODECUS.

Body stout, and distinctly segmented, with lateral processes close together. Ocular tubercle
anteriorly situated, long, with four well-developed eyes.

Proboscis immovably articulated to the trunk and ventral in position ; long, tapering, slender.

Chelifori absent.

Palps 6-jointed.

Oviger 6-jointed ? no terminal claw.

Legs short; genital apertures on the second coxe of all the legs in female. (Male as yet
unknown.)

I have considered the affinities of this and of the succeeding genus in the intro-

duction to this memoir.

PYCNOGONIDA. be

Oo

AUSTRODECUS GLACIALE.
(Plate VIIL, fig. 1.)

Specific characters :—
Body stout, segmented, with lateral processes close together.
Proboscis long, tapering and curved near the extremity.
Chelifori absent.
Palps 6-jointed ; terminal joint articulated to one side of the penultimate.
Ovigers 6-jointed ?
Legs short, first coxee armed dorsally with two spurs.
Abdomen long and slender.

This is a diminutive species ; the entire animal does not cover a space 8 mm.
square.

The trunk is stout and distinctly segmented ; the lateral processes are not widely
separated, but as they are rather short and tapering, the intervals at their distal
extremities are very pronounced. The first coxe, which are the largest, all bear
dorsally a pair of stout tubercular spines which are very prominent. Each of the four
segments of the trunk bears a stout tubercle of some elevation in the middle line, and
close to its posterior border.

The Cephalon is scarcely expanded, and almost fills the interval between the first
pair of lateral processes and their first coxe. Anteriorly it bears a very long Ocular
tubercle which is directed obliquely forwards, flask-shaped and truncated at its extremity,
on the upper surface of which, in a compact group, are four very well-cleveloped eyes.

From the truncated end of the trunk the Abdomen projects horizontally ; it is rather
long and not separated by an articulation. On the ventral surface of the trunk a
slightly raised band passes transversely between the first three pairs of lateral processes,
with the last pair the band is interrupted in the middle line.

The Proboscis is long and of a peculiar shape, not unlike the snout of a weevil
beetle. It is movably articulated to the body, and for about one-third of its length it
is not disproportionately slender, then it tapers rather rapidly to a long and very
slender structure, curved downwards near the tip. _ It is quite smooth and presents an
annular appearance which is less distinct proximally.

The Chelifori are quite absent.

The Palps are six-jointed and arise above but well to the side of the proboscis
(fig. 1b). The first joint is short and very stout, the second is long and extends
beyond the extremity of the ocular tubercle. The third is very short and its distal
limit indistinct. The fourth joint is rather more than half the length of the second.
The second joint bears the stumps of several spinous sete along its length; on the
fourth joint a similar number of curved spinous sete occur, and these increase in size
to the distal extremity of the joint, which also bears a few finer sete and a small
distal fringe. The last two are quite small and rather densely clothed with small sete.
The last one is articulated to one side, and not at the end, of the penultimate, and

the setze oceur mainly on the outer side.

54 T. V. HODGSON.

The Ovigers arise ventro-laterally, close to the angle formed by the cephalon and
the first lateral process. They are extremely small, and it is open to question whether
they are mature or not. As the removal of one of these appendages involves serious
risk to the only specimen, it cannot be very satisfactorily described. Not less than
six joints can be distinguished, the first three of which are very small. A small body-
process from which the appendage arises may be an additional jot. The terminal
joint is the longest, it is rounded at the extremity and does not carry any trace of a
claw, nor are setee of any kind discernible.

With regard to the Legs. the first coxa has already been alluded to as the largest
of the three, the other two are very little if any shorter, and the second is dilated
distally. It is difficult to get the limb in one plane for measurement, and the
joints appear subject to some variation. The proportion of the joints appears to be
3°5: 3: 2°5: °5: 2°5. The femur is stout, and the two following joints decrease in
calibre. The limb bears a very few scattered sete, most numerous on the second
tibia. The tarsus is very small and cup-lke, with two or three spinous setz
ventrally ; the propodus is proportionately long, slightly curved, and bearing a few
sete. On its ventral margin it carries a row of sete, but there is nothing very
distinctive about them. The claw is short and stout, and is accompanied by two
slender auxiliaries.

The only example of this peculiar species is a female, and the Genital apertures
are found in the middle of the second coxee of all the legs.

Taken by the dredge in Winter Quarters before the ship was frozen in. Ten
fathoms or less.

AUSTRORAPTUS.

Body with spurs on the lateral processes and first coxee. Segmentation very imperfect.
Proboscis stout at the base, terminating in a point.

Chelifori rudimentary.

Palps 6-jointed.

Ovigers 10-jointed, without terminal claw or denticulate spines.

Legs comparatively long, terminal claw with two auxiliaries.

AUSTRORAPTUS POLARIS.
(Plate VIIL, fig. 2.)

Specific characters :—
Body rather stout, with prominent spurs on the lateral processes and the first coxe.
Proboscis half the length of the trunk, pointed.
Palp 6-jointed, the terminal joint is twice as long as its predecessor, and articulated at an
angle to it.
Oviger 10-jointed, without terminal claw or denticulate spines.
Legs long, terminal claw with two small auxiliaries.

The body is rather robust, with long lateral processes which arise close together
and diverge considerably. These are provided dorsally with a pair of stout tubercular
spines which exist also on the first coxee, where they are greatly exaggerated.

PYCNOGONIDA. 55

The Cephalon is considerably enlarged, and almost completely fills the interval
between the first pair of lateral processes.

The Ocular tubercle is stout and_ tall, terminating in a cone above the four
well-developed eyes. It lies well to the front of the cephalon.

The Abdomen is long, cylindrical, almost horizontal, and not separated from
the body by an articulation. The extreme length and breadth of the trunk is as
6 to 5°5, the abdomen increasing the length to 7°5. The articulation of the trunk
is indistinct, that separating the last segment being non-existent. The entire body
appears to be perfectly smooth.

The Proboscis is about half the length of the trunk; it lies underneath the
cephalon, directed obliquely downwards ; it is stout and cylindrical for the greater
part of its length, tapering off to a sharp cone. It is movably articulated to the
trunk.

The Chelifori are rudimentary ; the scape is well developed, stout, not setose, a
little longer than the cephalon; the chelz are reduced to a knob, inclined inwards at
an angle of about 45°, with only the merest traces of fingers.

The Palp is short and only possesses six joints. It rises close to the proboscis,
below and outside the chelifori (fig. 2a). The first joint is short and stout, and
the second is three times as long; the third is again very small and, forming an
elbow, is shorter on one side than the’ other. The fourth is the longest joint,
though but little longer than the second, the only sete visible forming a small
distal fringe. The following joint is characteristic; it is small, and its inner margin
is just half the length of its outer border; this outer border is well supplied with
setee distally. To the oblique termination of this joint the sixth and last joint
is articulated. It is twice the extreme length of its predecessor and richly setose on
its outer border and extremity.

The Oviger is 10-jointed and rises ventro-laterally at the angle formed by the
first lateral process with the cephalon (fig. 2b). It is a short appendage ; the first
three joints are short and stout, the second and third are sub-equal in length, but
not in diameter, and nearly twice the length of the first; the two following are the
longest joints, the fifth being a trifle longer than the fourth and sparingly setose ;
the sixth is short, the seventh is longer, and the three terminal ones progressively
decrease in length and diameter, the last one being very small. The last five joints
are sparingly supplied with sete. On the terminal joint there are three long and
stout ones. There is no terminal claw nor are there any special spines. The oviger
of the male has not been removed, but does not differ essentially.

The Legs measure some 18 mm. in length. The second coxa is fully as long as
the other two together, and is much enlarged distally. The femur and first tibia are
sub-equal in length, and the second tibia is a very little longer; the tarsus and
propodus together are rather more than one-third the length of the sec« md tibia. The
tarsus is very small and cup-like, richly setose ventrally, the sete being stout, one

T
VOL, Ii.

56 T. V. HODGSON.

especially so. The propodus is very slightly curved and covered ventrally with
short spinous sete, with, proximally, a row of four stout spines. Dorsally the sete
are small and scanty. The terminal claw is large, more than half the length of
the joint, and accompanied by two small auxiliaries. These claws arise on a process
from the oblique termination of the joint. The extreme end does not project much
beyond, and is supplied with numerous spinous sete. The rest of the limb, coxe,
femur, and tibiz are fairly well covered with very small sete; their precise
distribution is not easy to observe; but they appear to be deficient laterally; they
are most abundant on the second tibia. The lateral line is well marked on the
three largest joints.

The specimen above described is an adult female, and shows conspicuous Genital
apertures on a swelling at the extremity of the second coxa of all the legs. An
adult male shows smaller apertures on the three posterior legs only.

The female was taken in 100 fathoms, rough ground, off the Barrier, in
Wate 78° 16ni4"S;, Lone. 197741047 ie

The male was taken in 300 fathoms, mud, off the Barrier, in Lat. 71° 25'40" S.,
Long. 185° 39/06" E.

RHYNCHOTHORAX.
Rhinchothorax, O. G. Costa, Microdoride Mediterranea (1861), p. 7.

1 have not seen Costa’s original description of this genus or its attendant species.
In the ‘Challenger’ Report (14) it is included by Dr. P. P. C. Hoek in his list of
the then known species of Pycnogonida, and at the same time condemned as being
insufficiently described. It is not a little remarkable that out of ten species then
recorded from the Mediterranean only one is described in Dr. Dohrn’s monograph (8).
Zoologists are indebted to that author for the careful and full descriptions of the
Pycnogonida therein recorded. The genus and species of Rhinchothorax mediterraneus
Costa are fully described, and differ in many particulars from the original description.

Dr. Dohrn states —

That the Chelifori are absent.

That the Palp is eight-jointed, but that fusion has taken place, reducing
the number of distinct joints to five. Five distinct joints are figured,
the limits of the remainder being obscure.

That the Ovigers are eleven-jointed. In both figures, however, only ten
joints are shown.

I have no hesitation in placing the species described below in the genus Rhyncho-
thorax as defined by Dr. Dohrn for these reasons: the general aspect of the animal is
similar; the proboscis is cleft at its extremity ; though the palps are only five-jointed,
the feebly-developed extremity seems to indicate some reduction is taking place ; and
the ovigers are ten-jointed, and the exact counterpart of those figured by Dr. Dohrn.

PYCNOGONIDA.

on
has |

RHYNCHOTHORAX AUSTRALIS.
(Plate VIIL., fig. 3.)
Specific characters :—

Body very robust, with lateral processes quite close together, and with median tubercles on
the segments.

Chelifori absent.

Palps 5-jointed, the second joint with a very strongly developed spur dorsally.

Ovigers 10-jointed, with a terminal claw, the lasts four joints with a couple of spines on an
enlarged base..

Legs short, terminal claw with two small auxiliaries.

Body very robust, with the lateral processes short and quite close together, widest
across the first lateral process, and about half the breadth across the last.

The posterior articulation of the trunk is deficient, but immediately in front
of where it should be, as on the preceding segments, is a stout median tubercle, bluntly
pointed, and very slightly inclined forwards.

The Cephalon is expanded, but very short. The Ocular tubercle, which is stout,
projects forwards and upwards over the base of the proboscis. It bears four well-
developed eyes, the posterior pair being a little the larger, and terminates above them
in a short cone. Measured from the anterior margin of the ocular tubercle, the
cephalon is half the length of the first segment of the trunk.

The Abdomen is long, about as long as the two combined segments from which
it originates.

Proboscis is stout, conical, a little longer than the first trunk segment. A
conspicuous slit marks the mouth as the animal lies in its normal position.

Chelifori, no trace.

Palps. These appendages only comprise five joints, and are very curiously
modified (fig. 3a). Each rises at the side of the proboscis and extends but little
beyond it. The first joint is short and stout, the second is the longest of the
appendage ; its dorsal extremity is prolonged forwards and upwards as a stout spur.
The third joint is about half as long as the shaft of the second, it is enlarged distally,
a stout dorsal tubercle bearing a tuft of sete; a few other sete are more scattered.
The fourth joint is small and setose, while the fifth, which is also richly setose, is
reduced to a mere button.

The Oviger is very slender, ten-jointed, and rises ventro-laterally at the neck
(fig. 3a). The first three joints are short, and progressively lengthen, but only to a
slight degree. The fourth is nearly as long as the three together. The fifth 1s
shorter, but swollen distally. The sixth is shorter still. No setee are discernible on
any of these joints. Of the four terminals the first three are sub-equal in length,
but their dorsal surfaces become more and more curved. Ventrally, also, there are
prominent projections which bear the denticulate spines. The terminal joint is very
broad, and a little longer than the others; its dorsal outline is very much curved,
and ventrally a large swelling occupies almost the whole surface; one small spine is

Tt 2

58 T. V. HODGSON.

all that is visible. A prominent claw terminates the appendage. The denticulate
spines are few in number, two on each of the first three jomts. They are worn, and
all that remains is a slender shaft of uniform diameter with three terminal teeth, of
which the middle one is the largest.

The Legs are short. The three coxee are short and stout, the second is by a very
little the longest, but the first has nearly twice its diameter; it also bears a tubercle
smaller than, but similar to, those borne on the middle line of the trunk. The femur
is stout, and not so long as the three coxze together, but the remainder of the
appendage is much more slender. The proportions of the two tibie are as 3 to 2,
the tarsus and propodus together being as long as the second tibia. The tarsus is a
very small joint, its ventral surface being covered with minute spinous sete. The
propodus, which is curved, has a row of them along its ventral margin, separated by
rather wide intervals; several sete are scattered dorsally. The terminal claw is
stout and is accompanied by two slender auxiliaries about one-third its size. A few
setee are scattered on other parts of the appendage, but they do not form a prominent
feature.

The Genital apertures are distinct on the second coxee of the last pair of legs only,
and this joint is much swollen in consequence.

This species, of which there is only a single specimen, was found by Mr. Kirk-
patrick on a sponge. Winter Quarters, at a depth of 178 fm., 7 Aug., 1902.

COLOSSENDEIS.

Body ovoid or elongate, with the lateral processes close together or widely separated, as a general
rule without segmentation. Cephalon small. Eyes well developed or absent.

Proboscis very large, often much longer than the body, and movably articulated to it.

Chelifori very rarely present, rudimentary.

Palps very long, 10-jointed, third and fifth joints the longest, more or less setose.

Ovigers very long, 10-jointed, fourth and sixth joints the longest, the last four joints bearing
several rows of spines usually dentate. A terminal claw.

Legs without auxiliary claws ; the three coxal joints short.

Abdomen of moderate dimensions, movably articulated to the trunk, sub-clavate.

Genital apertures on the second coxa of all the legs.

I defined this genus in comparison with Decolopoda in the Zoologischer Anzeiger
(13), retaining as far as possible the words of Jarzynsky. Certain characters made
use of by Professor G. O. Sars (25) have been incorporated, since his definition has
become inapplicable im certain important features.

No less than eighteen species and two varieties have been described. Through
the generosity of Professor EH. L. Bouvier I have been permitted to examine the
collection of Colossendeids made by the ‘ Travailleur’ and ‘ Talisman,’ the description
of which is not yet published. The identity of these species with the known species,
or otherwise, has not yet been fully established, but four new species from the
Antarctic Regions are now described.

PYCNOGONIDA. 59

COLOSSENDEIS AUSTRALIS.

(Plate IX., fig. 1; Plate X., figs. 1 and 2.)
Specific characters :—

Body stout, with lateral processes widely separated, minutely scabrous, the spines being arranged
in distinct rows on the appendages.

Proboscis enormous, bottle-shaped, more than half as long again as the body. Eyes, four, well
developed.

Palp 10-jointed, the eighth and ninth joints equal, the tenth longer.

Claw of legs less than half the length of the propodus.

Under a lens the entire animal exhibits a beautifully mottled appearance, which,
to a greater or less extent, appears to be characteristic of the genus. The Body
shows the faintest traces of segmentation ; the cephalon is short and only very little
expanded, and the first pair of lateral processes is placed close against it..

The Ocular tubercle is situated in the middle of this area and is stout, with four
well-developed eyes, two anterior and two posterior, the latter smaller than the others.

The Proboscis is of much greater diameter than the body, to which it is movably
articulated ; throughout the greater part of its length it is curved downwards; the
mouth is very large. The organ is covered with minute spines, which seem to have, to
some extent at least, an indistinct linear arrangement; the difficulty of making out
their precise arrangement is accentuated by a growth of polyzoa.

The Abdomen is of moderate dimensions and somewhat clavate.

The ten-jointed Palp arises ventro-laterally, as close as possible to the proboscis.
The two first joints are very short, and the third is rather more than twice the length
of the fifth ; the fourth is small; the sixth is barely one-third the length of the fifth,
and the seventh is about half as long again as its predecessor; the eighth and ninth
are shorter and sub-equal ; the terminal one is absent from one side and injured on the
other, but in the other specimen available it is a little longer. The lateral line appears
along the greater part of the appendage. The entire limb is spinose, beginning with
the third joint, and the minute spines are arranged longitudinally in rows as far as the
end of the fifth joint, which, with the two preceding, bears a more or less complete
whorl of spines at its distal extremity. Beyond the fifth joint the spines become stiff
setee rather than spines; they are larger and more abundant and irregular, besides
being aggregated on the ventral and inner side in the natural position of the limb.

The Ovigers are very long and, as characteristic of the genus, 10-jointed (fig. 1a).
They arise from a small body-process immediately behind the palps, but nearer the
middle line. The first three joints are small, the fourth and sixth are the longest and
sub-equal, the fifth being about a quarter their size. The last four are sub-equal, and
the appendage terminates in a small claw. The lateral line is distinctly marked. The
entire limb is spinous. A few minute spines exist on the first three joints, beyond
these they are arranged more or less clearly in lines and are more numerous. There
is also a fringe of small spines on the outer margin of the distal extremity of each

60 T. V. HODGSON.

joint, but these are either inconspicuous or absent on the four terminal joints. With
regard to the characteristic groups of spines on the four terminal joints, there are four
rows on the three proximal joints and three only on the terminal joint. In both
specimens the spines are so much worn-as to give but a feeble idea of their true
character (Plate X., figs. 1 and 2). The large size of the sockets in which they are
planted is remarkable. The most ventral row, that which lies nearest the sea
bottom in the natural position of the animal, comprises a small number, less than a
dozen, of large stout spines. The second row, which in this species is not separated
from the first by any conspicuous interval, contains approximately double the number
of smaller spines; the sockets of this row are sometimes crowded together, and the
spines are smallest and most crowded at the proximal end of the joint, and are also
deflected from a straight line by the articulation of the succeeding jomt. Two other
rows follow, but these have not the mathematical regularity of the former, nor are
they so much deflected ; they are reduced in number, but not in size. In structure the
large spines appear to consist of a stout base almost circular in section and composed
of a strong chitinous investment having a protoplasmic core; the spine tapers to
a blunt point much worn, but with enough left to indicate a flattened blade at the
extremity.

The Leg attains a length of 115 mm. The three coxe may be regarded as
sub-equal in size,and short. The two tibie are the longest joints and sub-equal, except
in the first leg, where the second tibia is a trifle shorter than the first. The femur is a
little shorter, and the tarsus less than half the length of any of the three preceding
joints ; the propodus is just over half the length of the tarsus. On the first coxa
there is dorsally and ventrally a median line of reddish colour, which appears to
indicate the presence of a slight groove. On the second coxa the lateral line begins
on each side of the joint, and passes to the extremity of the limb. The three coxze
are minutely scabrous and possess a small fringe of minute spines at their distal
margins. The remaining joints are more or less covered with these fine spines,
which become a little more conspicuous as the extremity of the appendage is reached.
Six rows are fairly well defined throughout the limb, a median dorsal, a median ventral,
and two lateral, one on each side the so-called lateral line. The distal extremity of
each joint bears a fringe of spines on the inside of the bend, largest and most
conspicuous on the second tibia. The terminal claw is small, less than half the
length of the propodus.

The Genital apertures occur on the second coxa of all the legs in both sexes,
as shown in figs. 1b and le.

The above description has been prepared from an example taken in deep water.
Another from shallow water presents certain differences: first, it is more spinose,
especially the proboscis and the limbs; on the legs four additional irregular rows of
spines may be distinguished between the six described for the deep-water specimen,
two of these are dorsal and two ventral: and secondly, in the comparative length of

PYCNOGONIDA. 61

certain joints. The third joint of the palp is distinctly less than twice the leneth of
the fifth, and the fourth joint of the ovigerous leg is a little longer than the sixth.

The nearest ally of this species seems to be C. proboscidea, Sabine, from which,
however, it may be instantly recognised by the wider intervals between the lateral
processes and the presence of well-developed eyes.

Two specimens of this species were taken, one off Cape Wadworth, Coulman Island,
8-15 fm.; bottom : stones; the second off Mounts Erebus and Terror, 500 fm.: bottom:
stones.

This latter specimen is the carrier of some half-dozen cirripedes of the genus

oOo
oO

Scalpellum.

COLOSSENDEIS GLACTIALIS.

(Plate IX., fig. 2; Plate X., figs. 3 and 4.)

Specific characters :—
Body apparently smooth, with lateral processes widely separated, and four well-developed eyes.
Proboscis not quite so long as the trunk, slightly dilated about the middle, and covered with short

spinous sete.
Palps, three terminal joints sub-equal and densely setose, with wide and deep constrictions at

the joints.

The body is rather stouter proportionally than the last two species, and though
apparently smooth, a lens reveals a median row of extremely minute sete.

The Cephalon is not expanded beyond the average width of the body.

The Ocular tubercle is stout, and bears four eyes, the anterior pair larger than the
posterior; the portion above the eyes is acutely pointed, but this feature is variable
in size. The setous character of the proboscis is not always easily discernible ; in one
specimen it is prominent, in others less so, even when not concealed by a growth of
polyzoa. It can hardly be said that these sete are arranged in any definite manner,
but in places they give the impression of ill-defined rows.

The Abdomen is short and articulated to the trunk. The Proboscis is as defined
among the specific characters and flexibly united to. the trunk.

The Palps arise on the ventral side of the proboscis (fig. 2); the first joint is
rather more prominent than usual, and is readily seen from the dorsal surface. The
second joint is shorter, the third is considerably the longest of the appendage, the
fourth is quite short, and the fifth is approximately two-thirds the length of the
third; this joint has a faint constriction at about two-thirds of its length. The
following joint is short, the next a little longer, the three terminal joints being short
and sub-equal. The extremity of the palp has a peculiar appearance, owing to the
seventh, eighth, and ninth joints, and to a less extent the sixth, having their distal
extremities rounded off like the shoulders of a wide-mouthed bottle, so that each
joint seems balanced on a narrow base. The entire appendage is beset with stiff sete,
almost spinous in character. On the third joint they are short, somewhat sparsely
distributed, and appear to be arranged in rows. A whorl of stouter sete: (spines ‘)

62 T. V. HODGSON.

surround the distal extremity of this joint and the next ; beyond this the setze are so
thickly distributed that it is scarcely possible to make out any definite arrangement.
On the fifth joint some of the setee are distinctly longer than the majority, and from
this joint the setee on the inner side of the appendage, in its natural position, are much
the longest.

The Ovigers arise immediately behind the palps on a conspicuous body-process
close to the middle line (fig. 2a). The first three joints are small, and bear spinous
setee of small size. The fourth and sixth are very long and sub-equal, the fifth being
not more than a quarter of their length. The four terminal joints are sub-equal in
length, but decrease in stoutness. The entire appendage is setose. On the fourth
joint the setze are small and arranged in rows, and on the outer margin, at about
two-thirds of its length, a small but distinct, rounded protuberance occurs. On the
succeeding joints the setee or spines, whichever they may be called, are more thickly
distributed. The characteristic spines of the four terminal jomts present very slight
differences from the two preceding species. On the ventral side of the limb in its
natural position are two rows of these spines separated by a conspicuous interval ; the
more ventral of these two rows consists of a few large spines, the other contains
approximately double the number of smaller spines. Dorsally, and separated by an
interval, are two rows of smaller spines, which are not, however, arranged with such
precision as the others. Close examination reveals the fact that the intervals between
the rows of spines are more apparent than real, this effect being due to the set of the
first two rows and the third group or double row; the second row is deflected at the
extremity by the articulation of the succeeding joint. The spines do not present
any special peculiarities, being more like true spines than in the other species here
described. They are somewhat curved or falciform (Plate X., fig. 3). The terminal
claw is of moderate dimensions, rather slender, but with a stout base; in most of the
specimens the stout base is all that is left. All four terminal joints are dorsally
covered with short spinous setz set in sockets (Plate X., fig. 4). In this species they
are much more numerous than in the other three.

Concerning the Legs, the first coxa has a slightly greater diameter than the others,
and bears the dorsal and ventral mark so characteristic of the genus. The other two
coxee are nearly equal in length and all are minutely spinose. The Genital apertures
oecur on the second coxze of all the limbs, and the lateral lime beginning on that
joint is conspicuous to the end of the limb. The first tibia is the longest joint of the
limb, the femur is very little shorter, the second tibia approximates to three-quarters
the length of the first, and the tarsus to very nearly half its length; the propodus is
shorter than the tarsus by nearly a third, and the claw is less than half the length of
the propodus. The entire limb is covered with minute setee, which, along the dorsal
surface at any rate, have a distinct linear arrangement; ventrally this becomes
indistinet from the second tibia onwards. The distal extremity of each joint,
including the coxee, is more or less completely girdled with spines, minute up to

PYCNOGONIDA. 63

the extremity of the femur, and most numerous dorsally; on the first tibia they
increase in size ventrally, and still more so on the second tibia; on the tarsus and
propodus the ventral sete: are comparatively long and conspicuous.

The specimen from which the above description was taken seemed to be an
exceptionally spinose individual. Seven specimens were obtained, and in the other
six all the features described above can be seen, though to a less degree, when not
concealed by a growth of polyzoa.

Winter Quarters, 12 to 25 fathoms.

COLOSSENDEIS FRIGIDA.
(Plate IX., fig. 3; Plate X., figs. 5 and 6.)

Specific characters :-—
Body smooth, with lateral processes widely separated. Four well-developed eyes.
Proboscis approximately twice the length of the trunk, dilated about the centre and quite smooth.
Palps, 10-jointed ; eighth joint half the size of the two terminals, which are sub-equal.
Ovigers, with a group of four or five irregular rows of special spines in addition to the two
primary rows.
Claws of legs about half the size of the propodus.

This last character, together with the spines and terminal claws on the ovigers,
readily separate this species from C. megalonyx, to which it appears very closely
related. :

A considerable amount of latitude must be allowed on the proportions of the
joints of the various appendages as a guide to specific discrimination. Thus the
proboscis varies in length from 11 mm. to rather more than 21 mm., and the trunk
to the base of the abdomen, from rather less than 6 mm. to rather more than 1] mm.,
but the longest proboscis does not coincide with the longest body. The same sort of
variation occurs throughout.

There is no trace of segmentation in the trunk, and the Proboscis is articulated to
it, hence the variation of the angle to which it may be inclined.

The Ocular tubercle is stout, sharply conical above the eyes, which are well
developed and four in number.

The Abdomen is quite small and articulated to the trunk.

The Palps are ten-jointed. The third joint is much longer than the fifth, which
reaches almost to the extremity of the proboscis. The fourth joint is very small, and
the seventh is slightly longer than the sixth; the eighth is quite short, the two
terminals being twice its size and sub-equal. Towards the extremity of the fifth joint
very minute setz make their appearance, and on the rest of the appendage they are
scattered in more or less definite rows.

Ovigers : These appendages arise close to the middle line behind the palps (fig. 3).
The first three joints are very small, the fourth and sixth long and sub-equal, the
sixth as a rule extending beyond the proboscis. The fifth joint is about half the
length of the sixth. The four terminal joints are sub-equal, and the claw has a
peculiar appearance, as if the inner margin had been bevelled off at a very acute

VOL. III. U

64 T. V. HODGSON.

angle. In its perfect condition it is rather long and slender, especially the distal
half. Something like one-half of this slender portion, at the tip of the claw, is
flattened dorso-ventrally to form a sort of protective shield to a thin membranous fold
lying like a knife-edge on the under surface of the claw throughout its distal half
(fig. 3a). The claw is covered with very minute hairs. The characteristic spines are
very numerous, and are arranged in two sharply defined lines followed by a closely
arranged group in which five rows can be distinguished. A distinct interval separates
the first two rows from each other and from the group referred to above. The
spines of the first row are long, slender, lanceolate in shape, and set as closely
together as possible (Plate X., figs. 5 and 6). Those of the second row are approxi-
mately double in number, shorter and more spathulate, their essential structure being
the same. They have a fairly stout base tapering to the centre, where it becomes
a flat blade, the entire margin of which is provided with minute teeth visible
under a one-inch objective. In the group of spines there are five rows arranged
in an imbricate manner and as the spines of these rows alternate fairly regularly
oblique rows of eight spines may be distinguished in the broadest part of the group.
In structure they resemble those of the second row. Sete are sparsely distributed
over the appendage and though very minute they are not difficult to distinguish.

The legs of the numerous specimens average between 58 mm. and 106 mm. in
leneth; the proportions of the joints do not, however, vary greatly. The first coxa
bears a reddish line marking a very shallow groove dorsally and ventrally ; the lateral
line begins on each side of the second coxa, and is continued to the extremity of the
limb. The three.coxe are sub-equal. The femur is the largest joint of the limb
as a rule, the other joints decreasing in size to the extremity. The claw is about half
the leneth of the propodus.

The Genital apertures occur on the second coxa of all the limbs of both sexes. The
lees are apparently quite smooth, even to the touch, but close examination shows faint
traces of rows of sete. In some of the larger specimens these are a little more conspicuous.

Specimens of this species were taken in Winter Quarters in depths varying from
5 to 178 fathoms, and the name is derived from the fact that two of them had to be-
taken to the ship dry, a distance of nearly two miles, at a temperature of — 50° Fahr.
They suffered in consequence. Another specimen taken in 300 fathoms; bottom, mud ;
off the Barrier, 27.1.’02, is referred to this species.

COLOSSENDEIS RUGOSA. .
(Plate IX., fis. 4; Plate X., fig! 7.)
Specific characters :—

Proboscis half as long again as the body, slender, dilated about the middle, with a median row of
curved spines dorsally along the proximal half.

Body smooth, with lateral processes widely separated, and, with the first coxa, dilating distally.

Palps 10-jointed, the eighth very short ; the ninth rather more than twice its length ; the terminal
one a little larger still.

Legs provided with rows of spines, claw large. :

PYCNOGONIDA. 65

This species in general appearance very closely resembles the last, but may
be readily distinguished by its spiny character and the features quoted above. .

The Body is quite smooth, the cephalon short and without any constriction
indicating a neck.

The Ocular tubercle is stout, with four well-developed eyes, the anterior pair
being larger than the posterior pair. Above the eyes the tubercle is acutely conical.

The Proboscis is half as long as the body as indicated in the specific characters,
and besides the median row of spines there is a lateral row of a few, widely
separated. The proboscis is movably articulated to the body, and obtusely pointed
distally.

The Abdomen is small, somewhat clavate, but presenting no special feature.

The Palps arise on the ventral side of the body, as close as possible to the
proboscis. They arise on a process of the body which is usually regarded as the first
joint, but which has always appeared to me to be doubtful whether it is a real joint or
not. In this particular species it is definitely a body-process and not a true joint.
The succeeding joint, here as elsewhere called the second, is very short, a mere ring-
like segment. The third is considerably the longest joint of the appendage, slender
and furnished with a few prominent curved spines; the fourth is quite small; the
fifth is two-thirds the length of the third; and a short distance from the distal
extremity there is a distinct constriction as though there had been a joint there and
it had fused; the sixth is short, and the seventh is about half as long again; the
eighth joint is very short, scarcely half the length of the sixth; the ninth is fully
twice the length of the eighth, and the terminal one a little longer, rounded at the
extremity. From, and including the fourth joint, the entire organ is covered with
minute spines, too plentifully distributed to assert any regular disposition.

The Ovigers arise laterally from two body-processes close to the middle line and
immediately behind the proboscis (fig. 4). The first three joits are very small and
sub-equal in length; the fourth and sixth are very long and sub-equal, the fifth being
about one-third of their length; of the four terminal joints, the proximal is the
largest. The claw is of moderate dimensions. The entire appendage is covered with
very minute spines, which become numerous from the fourth joint, and appear to be
very generally distributed. The characteristic spines of the four terminal joints are
limited to four rows with an occasional small spine which may perhaps be regarded
as the remnant of a fifth row. It is unfortunate that in the only specimen obtained
(Plate X., fig. 7) these spines are very much worn. An interval separates the two
first rows, and another interval separates the second row from the remainder.

The spines of the first row are long, slender and few in number. They have
a somewhat stout base which, as far as can be judged without cutting sections,
appears to be rounded on one side and flattened or somewhat concave on the other ;
they are constricted in the middle, and produced onwards as a flat blade with dentate

margins. The spines of the second row are smaller, twice the number, and placed as
U 2

66 T. V. HODGSON.

close together as possible. In both these rows the spines are set at right angles to
the joimt, in the other rows they are arranged parallel to the length of the joint.
All these are essentially the same in character, but in the “ parallel” series, the spines,
being viewed more laterally, appear to be curved and the blade forms a very
shallow scoop.

The Legs are provided with longitudinal rows of curved spines, not very
numerous, especially on the ventral surface, most abundant and conspicuous on the
femur. The first coxa is conspicuously broader than the others. The lateral
processes of the body are narrow proximally and widen distally, the first coxa
continuing this widening. The two following cox are of less diameter, sub-equal in
length, the distal extremity of each is fringed with minute spines, the fringe,
however, not being complete. The femur is conspicuously the longest joint of the
limb, the other joints progressively shorten, the amount of decrease being obvious.
The claw is nearly the length of the propodus. <A few additional spines are to be
found ventrally at the distal extremity of some of the joints.

The Genital apertures open on the second coxa of each leg.

A single specimen of this species was taken off the Barrier in lat. 78° 25’ 40" S.,
long. 185° 39' 6” E., 300 fms., bottom, mud, 27 Jan. 1902.

In the examination of this collection my thanks are primarily due to the Council
of the Marine Biological Association of the United Kingdom, and to Dr. EK. J. Allen,
the Director, for accommodation at their Plymouth Laboratory ; to Professor Chilton,
of Canterbury College, Christchurch, N.Z., for enabling me to make the preliminary
examination of our collections; to Mr. G. M. Thomson and Professor W. B. Benham,
of Dunedin, N.Z., for so kindly placing the whole of their collections at my disposal ;
to Professor EK. L. Bouvier, of Paris, for allowing me to examine the collection made
by the ‘Francais’ in the Antarctic as well as the unpublished collections of the
‘Travailleur’ and ‘Talisman’; to Professor Kraepelin, and particularly to Dr. G.
Pfeffer, for the opportunity to examine the collection from South Georgia, now in
the Natural History Museum at Hamburg; to Professor A. Brauer, and especially to
Dr. E. Vanhoffen, biologist of the ‘Gauss,’ for the facilities extended to me during the
examination of the ‘ Valdivia’ and other collections now in the Berlin Museum.

My best thanks are due to Mrs. L. E. Sexton for the drawings of Plates VI.
and IX., Plate II., Fig. 1., Plate V. (the entire animal), Plates X., Figs. 1-7, all of
which were executed with the greatest accuracy. I am further indebted to her for
some considerable assistance during the progress of the work.

Messrs. West, Newman and Co. have continued the preparation of the plates,
and I must thank them for the care they have taken,

ss]

10.

11.

15.

14.

15.

16.

Wi

18.

19.

PYCNOGONIDA. 67

LIST OF WORKS QUOTED IN THE TEXT.

. Boum, R. Uber die Pyenogoniden des Konigl. Zoologischen Museums zu Berlin, insbesondere iiber die

von 8. M. 8. Gazelle mitgebrachten Arten.
Monatsber. Akad. d. Wiss. zu Berlin, 1879, pp. 170-195, 2 pl.
Bouvier, HE. L. Observations préliminaires sur les Pyenogonides recueillis dans la région antarctique
par la Mission du ‘ Frangais.’
Bull. du Mus. d’hist. Nat., 1905, No. 5, pp. 294-7.

. Bouvier, E. L. Nouvelles observations sur les Pycnogonides recueillis dans les régions antarctiques

au cours de la campagne dirig¢e par M. Jean Charcot.
Comptes rendus des Séances Acad. des Sciences CXLII., 1906, pp. 15-22.

. CARPENTER, G. H. On some Pycnogonida from the Irish Coasts.

Sci. Proc. Roy. Dublin Soc., Vol. VIII., N.S., 1893, pl. IL., pp. 195-205, 1 pl.

. CARPENTER, G. H. On the Pantopoda.

In Herpmay, Ceylon Pearl Fisheries, Supplementary Report XIII., pp. 181-4, 1 pl.

. Core, L. J. Pycnogonids of the West Coast of North America.

Harriman Alaska Expedition, Alaska, Vol. X., 1904, pp. 249-298, pl. IX.—XXVI.

. Cot, L. J. Ten-leeged Pycnogonids, with Remarks on the Classification of the Pycnogonida.

Ann. & Mag. N. H., 7, Vol. XV., 1905, pp. 405-415.

. Donrn, Anton. Die Pantopoden des Golfes,von Neapel und der angrenzenden Meeresabschnitte.

Leipzig. 1881.

. Haswety, W. A. On the Pycnogonida of the Australian Coast, with descriptions of new species.

Proc. Linn. Soc., N.S.W., Vol. [X., 1885, pp. 1021-34, 3 pl.
Hopason, T. V. Crustacea.
Report on the Collections of Natural History made in the Antarctic Regions during the Voyage of
the ‘Southern Cross,’ 1902, pp. 257-8.
Hopeson, T. V. Ona new Pycnogonid from the South Polar Regions.
Ann. & Mag. N. H., 7, Vol. XIV., 1904, pp. 458-462, 1 pl.

. Hopeson, T. V. Scotia Collections. On Decalopoda australis Eights. An old Pyecnogonid

re-discovered.
Proc. Roy. Phys. Soc., Edinburgh, Vol. XVI., 1905, pp. 35-42, 2 pl.
Honveson, T. V. Decalopoda and Colossendeis.
Zool. Anz. Bd. XXIX., 1905, No. 8., pp. 254-6.
Hoek, P. P. ©. Report on the Pycnogonida dredged by H.M.S. ‘Challenger’ during the years
1873-76.
H.M.S. ‘ Challenger’ Reports, Zoology, Vol. 3. 1881.
Hork, P. P. C. Nouvelles études sur les Pycnogonides.
Arch. Zool. Exp. et Gen. IX., 1881, pp. 437-542, pl. XXTIT.-XXX.
Horx, P. P. C. The Pycnogonida dredged in the Faroe Channel during the Cruise of H.M.S.
‘Triton’ (in August 1882).
Trans. Roy. Soc., Edin., Vol. XX XII., 1883, pp. 1-10, 1 pl.
Horx, P. P.C. On Four Pyenogonids, dredged during the Cruise of the ‘ Challenger.’
Tijdschr. d. Ned. Dierk. Vereen. (2) V. 2-4, 1898, pp. 290-300, 2 pl.
JARzyYNSKY, T. Praemissus catalogus Pyenogonidarum inyentarum in mari glaciali ad oras Lapponiae
rossicae et in mari albo, anno 1869-70.
Soc. Natur. St. Petersburg. 1870.
Loman, J.C. C. Decalopoda Eights oder Colossendeis Jarz.
Zool. Anz., Bd. XXVIII, 1905, pp, 722-3.

T. V. HODGSON. .

20. Murnert, F. Pycnogonida.

The Danish Ingolf Expedition, Vol. IIT., 1899, Pt. 1, pp. 1-71., Tab. 1-5, Copenhagen.

21. Mirrs, E. J. Crustacea of Kerguelen Island (Pycnogonids, pp. 211-214.)

Phil. Trans. Lon., Vol. 168, 1879, pp. 200-214, pl. X.

22. Moéprus, K. Arktische and Subarktische Pantopoden.

Fauna Artica. Hine Zusammenstellung der arktischen Tierformen, mit besonderer Beriichsichtigung
des Spitzbergen Gebietes auf Grund der Ergebnisse der Deutschen Expedition in das Nordliche
Hismeer im Jahre 1898. Band II., 1901, Lief. i, pp. 35-64.

Méntus, K. Die Pantopoden der deutschen Tiefsee Expedition, 1898-99.

Wissenschaftliche Ergebnisse der deutschen Tiefsee Expedition auf dem Dampfer ‘ Valdivia,’

1898-99. Band 3, Lief. 6, 1902, pp. 175-196, Taf. XXIV.-XXX.

. Prurrer, G. Zur Fauna von Siid Georgien.

Jahrb. d. Hamburgischen Wiss. Anst. Bd. VI., Heft II., 1889, pp. 41-49.

. Sars, G.O. Pycnogonidea.

Zoology of the Norwegian North Atlantic Expedition. 1891.

}. SchimkEwirscu, W. Sur les Pantopodes, recueillis par M. le lieutenant G. Cherchia pendant le

voyage de la Corvette ‘ Vettor Pisani’ en 1882-85.
Atti della R. Accad. dei Lincei, Mem. (4) VI., pp. 329-347, 1 pl. 1889.

7. Scupuxiwirscu, W. Compte-rendu sur les Pantopodes.

Reports on dredging operations. . . . U.S. Fish Comm. 8.8. ‘ Albatross,’ during 1891. Bull.
Mus. Comp. Zool., Vol. XXV., 1893, pp. 27-43, 2 pl.

. Scumcewirscnu, W. Ueber die Periodizitiit in dem System der Pantopoda.

Zool. Anz. Bd. XXX., 1906, pp. 1-22.

29. Sruppine, T. R. R. The Nobodies: A Seafaring Family.

Knowledge, Vol. 25, 1902, chap. 4, pp. 185-9.

. THomson, G. M. On the New Zealand Pycnogonida, with Descriptions of New Species.

Trans. N.Z. Inst., Wellington, Vol. XVI., 1884, pp. 242-8, pl. 14-16.

31. Winson, E. B. The Pyenogonida of New England and Adjacent Waters.

Rep. U.S. Fish Comm. for 1878, pt. VI., 1880, pp. 461-506, pls. 1-7.

32. Winson, E. B. Report on the Pyenogonida.

teports on the Results of Dredging . . . . during 1880 by U.S. Coast Survey 8.8. ‘ Blake.” Bull.
Mus. Comp. Zool., Harvard, Vol. VIII., 1881, pp. 239-256, pls. 1-5.

PYCNOGONIDA. : 69

EXPLANATION OF THE PLATES.

PLATE I.
Fie. 1.—Phoxichilns australis. 2 x 2.
2.—Pseudopallene australis. Q x 3.
2a.—Oviger, five terminal joints. 9 x 20.
2b.—Denticulate spine from tenth joint. x 880.
3.—Pseudopallene cornigera. @. Oviger, five terminal joints. 9 x 20.
3a.—Denticulate spine from eighth joint. x 530.
Pallenopsis hiemalis. 9 x 3.
4a.—-Oviger, six terminal joints. x 27.

4.

PLATE II.
Fic. 1.—Pallenopsis villosa. 9 x 3.
la.—Chela. x 18.
1b.—Oviger. x 10.
2.—Pallenopsis pilosa. 9 Hoek. Oviger, five joints, terminal one missing. X 22.
3.—Pallenopsis hiemalis. 9. Terminal joints of leg. x 12.
3a.—Specimen from Cape Wadworth. Terminal joints of legs. x 12.

PLATE III.

Fig. 1—Nymphon hiemale. ¢ x 2.

la.—Palp. x 14..

1b.— Oviger, five terminal joints. 16.
Fia. 2.—Nymphon lanare. x 3.

" Qa.—Palp. x 14.

2b.—Oviger, five terminal joints. x 135.
Fic. 3.—Nymphon adareanum. g x 8.

3a.—Palp. x 70.

3b.—Oviger, five terminal joints. x 80.
Fria. 4.—Nymphon frigidum. x 10.

3a.—Palp. x 56.

3b.—Oviger, five terminalejoints. x 60.

PLATE IV.

Fie. 1.—Chetonymphon villosam. x 4.

la-—Palp: x 17.

1b.—Oviger, five terminal joints. x 17.
Fic. 2.—Cheetonymphon biarticulatum. 9? x 3.

2a.—Palp. x 27.

2b.—Oviger. x 16. =
Fie. 3.—Chetonymphon mendosum. 9 xX 4.

3a.—-Palp. x 20.

3b.—Oviger. .x 32.
Fig. 4.—Cheetonymphon australe var. austrinoruam. ¢ X 3°53,

4a.—Palp. xX 14.

4b.—Oviger. xX 13.

70 T. V. HODGSON.

PLATE V.
Fre. 1.—Pentanymphon antarcticum.
la.—Palp. xX 27.
1b.—Oviger. xX 40.
1c.—Denticulate spine from eighth joint. x 630.

PLATE VI.
Fig. 1.—Leionymphon grande. @ X 2.
la.—Oviger X 4.
1b.—Third leg, terminal joints. x 8.

1c.—Right oviger of immature specimen. X 4

1d.—Right oviger of immature specimen. X 4.
le.—Right oviger of immature specimen. X 10.
1f.—Right oviger of immature specimen. X 10.

Fie. 2.—Leionymphon minus. x 2.
9a.—Oviger. 9% xX 10.
2b.—Oviger. ¢ X 10.
2c.—Denticulate spine from joint of oviger. g X 260.

PLATE VII.

Fra. 1.—Leionymphon australe. 9 X 3.

1a.—Oviger, five terminal joints. 9 x 30.

1b.—Oviger, five terminal joints. g X 28.
Fic. 2.—Leionymphon spinosum. @ X 2.

2a.—Palp, five terminal joints. x 20.

2b.—Oviger, five terminal joints. x 20.
Fra. 3.—Leionymphon glaciale. 9 Xx 1°9.

3a.—Palp, five terminal joints. x 11.

3b.—Oviger, six terminal joints. X 11.

PLATE VIII.

Fig. 1.—Austrodecus glaciale. 9 x 15.
la.—Lateral view of body without appendages. x 15.
1b.—Palp. x 56.

Fig. 2.—Austroraptus polaris. @ x 5.
Ja.—Palp. x 40.
1b.—Oviger. xX 31.

Fig. 3.—Rhynchothorax australis. x 15.
Palp. x 72.
Oviger. xX 88.

PLATE IX.

Fig. 1.—Colossendeis australis. 9 xX 1.
Ja.— Oviger, four terminal joints. x 4.
1b.—Outlines of second coxa showing sexual aperture.
1c.—Onitlines of second coxa showing sexual aperture.

Fic. 2.—Colossendeis glacialis. Palp, terminal joints. X 8.
2a.—Oviger, four terminal joints. x 8.

Fic. 3.—Colossendeis frigida. Oviger, four terminal joints. x 8.
3a.—Terminal claw of Oviger. X 265.

Fig. 4.—Colossendeis rugosa. Oviger, four terminal joints. x 8.

O40

PYCNOGONIDA. 71

PLATE X.

Colossendeis.

Fic. 1.—C. australis. Special spine from eighth joint of Oviger. Principal row. x 100.
2.—C. australis. Special spine from eighth joint of Oviger. Second row. x 100.
3.—C. glacialis. Special spine from eighth joint of Oviger. Much worn. x 265.
4.—C. glacialis. Seta from dorsal surface of ninth joint of Oviger. x 265.
5.—C. frigida. Special spine from tenth joint of Oviger. Principal row. x 265.
6.—C. frigida. Special spine from tenth joint of Oviger. Second row. X 265.
7.—C. rugosa. Special spine from tenth joint of Oviger. Principal row. 265.

Nymphon.

Denticulate spines from tenth joint of oviger.

Fic. 8.—N. hiemale. x 350.

9.—N. lanare. x 455.
10.—N. frigidum. x 645.

Cheetonymphon.

Denticulate spines from oviger.

Fig. 11.—C. villosum, seventh joint. x 438.

12.—C. biarticulatum, tenth joint. x 630.

13.—C. mendosum, tenth joint. x 410.

14.—C. australe, tenth joint. x 480.

15.—C. australe var. austrinorum, tenth joint. 512.

Note.—The magnifications of Messrs. West, Newman & Co.’s drawings are approximate only. The
drawings were made on squared paper, with the assistance of an eyepiece micrometer, and in many cases
have been reduced to fit the plates.

VOL, III, X

72

T. V. HODGSON.

INDEX.

Ammothea charcoti, 40, 41.
Ammothea clausii, 40.

Ammothea communis, 3.
Ammothea curculio, 3.

Ammothea grandis, 40, 45
Ammothea hoeki, 3.

Ammothea wilsoni, 3.
Anoplodactylus neglectus, 2.
Anoplodactylus petiolatus, 2.
Ascorhynchus glaber, 3.
Austrodecus glaciale, 3, 53.
Austroraptus polaris, 3, 54.
Chetonymphon australe, 2, 32.
Chetonymphon australe, var. austrinorum, 2, 35.
Chetonymphon biarticulatum, 2, 28.
Chetonymphon brevicaudatum, 2.
Cheetonymphon mendosum, 2, 30.
Chetonymphon villosum, 2, 26.
Colossendeis australis, 3, 59.
Colossendeis frigida, 3, 63.
Colossendeis yigas, 3.
Colossendeis gigas leptorhynchus, 3
Colossendeis glacialis, 3, 61.
Colossendeis gracilis, 3.
Colossendeis leptorhynchus, 3.
Colossendeis meqgalonya, 3.
Colossendeis robusta, 3.
Colossendeis rugosa, 3, 64.
Cordylochele turqueti, 9.
Decolopoda antarctica, 3.
Decolopoda australis, 1, 3.
Leionymphon australe, 3, 46.
Leionymphon clausi, 3.
Leionymphon gibbosum, 2.

Leionymphon glaciale, 3, 50.
Letonymphon grande, 2, 41.
Leionymphon minus, 2, 44.
Letonymphon spinosum, 3, 49.
Leionymphon striatum, 2.
Nymphon adareanum, 2, 23.
Nymphon antarcticum, 2.
Nymphon brachyrhynchun, 2.
Nymphon friguhim, 2, 20;
Nymphon fuscum, 2.
Nymphon gracile, 2.
Nymphon gracilipes, 2.
Nymphon hamatum, 2.
Nymphon luemale, 2, 20.
Nymphon lanare, 2, 22.
Nymphon meridionale, 2.
Pallene dimorpha, 2.
Pallenopsis fluminensis, 2
Pallenopsis glabra, 2, 11.
Pallenopsis hiemalis, 2, 17.
Pallenopsis patagonica, 2, 20.
Pallenopsis pilosa, 2, 15.
Pallenopsis villosa, 2, 13.

Pentanymphon antarcticum, 1, 2, 36.

Phoxichilus australis, 2, 5.
Pseudopallene australis, 2, 10.
Pseudopallene corniygera, 2, 7.
Pycnogonum magellanicum, 2.
Pycnogonum magnirostre, 2.
Rhynchothorax australis, 1, 3, 57.
Tanystylum chierchia, 3
Tanystylum dohrnit, 3.
Tanystylum styligerum, 3.

West,Newman del.et kth

2.Pseudopallene australe.

SEV dopallene cornigera..

4. Pailenopsis hiemalis.

Plate II

: West, Newman lith
Pallenopsis.

2.P pilosa. ' 3.P hiemalis.

tarctic (Discovery) Exp. Plate III.

Nymphon. West, Newman delet lith.
38.N. adareanum. .
4.N.frigidum. Z

arctic (Discovery) Exp. Plate IV.

ae, yt
Wee jHOE
Wee

—=

« Chetonymphon.
feG. \alligcaaam: 2. C. biarticulatum.
3, C.mendosum. a, C, susteinerun..

“wnotjorejue uoYyduAURqUag
Yl Weurmoa py yeaAd ,

[9p toysag yt TP Bay

Plate VI.
West. Newman lith.

I,.minus.

ae

a
a
Sg
Hl
z]
fs)
dss
@
‘st

e

fs .L.grande.

D iscovery) Exp.

“Lei West, Newman delet lth.
Leionymphon. est, Newman dele

2.L.spinosum. 3. L.glaciale.

ctic (Discovery) Exp. Plate VII.

' A West, Newman sae
€. 2.Austroraptus polaris. 3. Rhynchothorax australis.

Plate IX.

West,Newman hth.

| Colossendeis.
2.C.glacialis. 3.C.frigida. 4.6. rugosa.

ce (Discovery) Exp. Plate X.

r

==...

a a

» Figs 8-15 West,Newman delet lth. -
ralis. Figs 384. C. glacialis. Figs 526. C. frigida. Fig.'7. C._ rugosa.
on hiemale. Fig.9.N.lanare. Fig10. N frigidum. ;

phon villosum. Fig 12.C.biarticulatum. Kig.13. C. mendosum.

. Fig.i5. C.austrinorum.

- =

fad Oecd Gi

HALACARIDA (ACARIENS MARINS).

Par LE Dr. E. L. Trovessart,

Professeur au Muséum d'Histoire Naturelle de Paris,
Membre Correspondant de la Zoological Society of London.

Avec 1 planche d’aprés les dessins de G. NeuMANN, Professeur & |’Ecole Vétérinaire
de Toulouse.

INTRODUCTION.

En terminant l'étude des Acariens rapportés du Pole Antarctique par lexpédition
de la ‘Belgica,’ auteur de ces lignes disait: “Il est regrettable qu’aucune espece
d’ Halacaride ne se soit rencontrée au cours des dragages opérés dans ces régions. Nous
savons par les matériaux rapportés par Pouchet ’ la suite du voyage de la ‘ Manche,’ et
par ceux plus abondants encore, qui ont été recueillis par 8. A. le Prince de Monaco,
pendant la croisiére de la ‘ Princesse Alice,’ sur les cdtes du Spitzberg, que les Acariens
marins sont nombreux et d’espéces variées dans les mers arctiques. J'ai peine a croire
quil n’en soit pas de méme dans les mers antarctiques. oe

Cette lacune se trouve aujourd’hui comblée. Les naturalistes de la ‘ Discovery ’
ont rapportés deux Halacaride, dragués au large de Granite Harbour. Tous deux
appartiennent & une seule et méme espice, tres intéressante, puisqu’elle se retrouve
au Péle arctique. I] est probable que l’on en découvrira d’autres par la suite.

La présence, dans les mers antarctiques, d’une espece d’Halacaridee, constituant
tout au plus une sous-espece d’un type déji connu dans les mers arctiques (//alacarus
[Leptospathis| Alberti Trt.), souleve une fois de plus la question de la bipolarité des
faunes.

Je n’ai pas l’intention de revenir ici sur cette question, qui semble avoir été
suffisamment discutée par Joubin,* Keehler,f Topsent,{ Dollo,§ Giesbrecht{ et d'autres, et

1 Résultats du voyage du §.Y. ‘ Belgica’ (Zoologie, Acariens), 1903, p. 10.

* Résultats du Voyage de la ‘ Belgica’ (Mollusques), 1903, p. 71; du méme, Bull. Mus. Océanographique de
Monaco, Cours d’Océanographie, 1905, p. 31, et suiv.

+ Résultats, ete. (Echinides), 1901, p. 36.

} Résultats, ete. (Spongiaires), 1901, p. 8.

§ Résultats, etc. (Poissons), 1904, p. 191, et suiv.
{ Résultats, ete. (Copépodes), 1902, p. 7.

2 DR. E. L. TROUESSART.

que l’on peut considérer comme parfaitemente résolue, dans létat actuel de la science.
On peut la résumer ainsi:

La théorie de la bipolarité est démentie par les faits : toutes les espeéces communes
aux deux poles sont des especes cosmopolites, qui se sont propagées peu-a-peu, & travers
les époques géologiques, soit par la continuité des continents ou le transport accidentel
(especes terrestres), soit par les courants ou le fond des océans (especes marines). En
définitive, la bipolarité wexiste pas.

I] serait trop long de citer ici toutes les espéces communes aux deux poles: je me
contenterai d’en donner quelques exemples :—

Parmi les Géphyriens, Spengel cite Priapulus caudatus, Lamarck.

Parmi les Mollusques, Joubin indique Janthina rotundata.

Parmi les Copépodes, Giesbrecht énumére les six especes suivantes: Oncea
conifera, UO. notopus, Microstella atlantica, Oithona similis, Pseudocalanus pygmeus,
Harpacticus chelifer.

Parmi les Acariens terrestres, j’al moi-méme indiqué Rhagidia (ou Norneria) gigas.

Parmi les Spongiaires, Topsent signale Leucosolenia lamarcki, Halichondria
pancea, Dendoryx incrustans.

Or, toutes ces especes sont cosmopolites.

Bien que S/alacarus alberti wait encore été rencontré que dans les deux mers
polaires, on peut prédire qu'il se retrouvera ailleurs. D’aprés ce que nous savons de la
distribution des animaux marins, il est infiniment probable que cette intéressante espece
existe dans plusieurs stations intermédiaires, et qu'elle est cosmopolite ou subcosmopolite.
Le fait quelle vit, dans les mers arctiques, & une certaine profondeur (entre 48
et 430 m.), confirme cette maniére de voir. On sait, en effet, que si la température du
fond descend dans les mers polaires & — 3°, elle ne s’éleve pas dans les mers tropicales
au-dessus de +2°, et lon peut consideérer cette différence de 5° comme insignifiante,
lorsqu’'il s’agit (animaux vivants toute l'année dans des eaux froides.

DESCRIPTION DE L'ESPECE ET DE SA SOUS-ESPECE.

Le sous-genre Leptospathis Trt., auquel appartient cette espece, semble assez
distinct d’Halacarus pour constituer un bon genre, et non plus une simple section
subgenérique.

L’allongement du rostre, la forme de l’hypostome, l’absence de piquant aux palpes,
la disposition de la cuirasse, la gracilité des pattes, etc., ont fourni & Lohmann!’ des
caracteres différentiels pour son ‘‘Chevreuxi-Gruppe,” qui correspond & notre 8.-G.
Leptospathis.

La forme du rostre, et surtout la gracilité de ’hypostome, qui indiquent une
différence notable dans le genre de nourriture, suffisent & earactériser ce genre.

‘Lohmann, Die Halacarinen der Plankton Expedition, 1893, p. 58 (Plankton Expedition der Humboldt-Stiftung).

ACARI. 3

LEPTOSPATHIS.

Leptopsalis Trt., Comptes Rendus, evii. (1888), p. 755 (non Leptosalis Thorell, 1882).

Chevreuai-Gruppe Lohmann, Halacarinen Plankton Exp., 1893, p. 68.

Leptospathis, Trt. Rev. Biol. Nord., vi. (1894), p. 174.

> stre ord Aus ee a, an.

Caractéres.—Rostre gréle et allongé ; hypostome long et gréle, plus étroit & la base
ou dans sa partie médiane, spatuliforme (et non triangulaire, comme chez [Zalacarus
proprement dit).

Type: Halacarus chevreuai Trouessart.

Le genre renferme les especes suivantes :

1. Leptospathis chevreuvi, Trt.

2. . nationalis, Lohm.

3: a hispida, Lohm.

4 m panopae, Lohm.

a: e hypertrophica, Lohm.
6. * thaleia, Lohm.

is 55 alberti, Trt.

Voici la diagnose de cette dernitre espece, telle que je l’ai donnée en 1902".

LEPTOSPATHIS ALBERTI TYPICA.

“Cette grande espéce est bien caractérisée par la forme de ses pattes. La cuirasse
est mince et peu développée, dépourvue de crétes et de lamelles. Le tronc est ovale,
un peu lobé par l'insertion des pattes, avec l’anus terminal. La plaque de I’épistome
est coupée carrément en avant, laissant le rostre 4 découvert; les plaques oculaires sont
subovales ; la plaque notogastrique est grande, ovale; la plaque sternale tres
développée, subtrapézoidale, étroite en arriére; les plaques coxales tres larges, se
rejoignent presque, en-dessous ; la plaque ventrale est petite, ronde, occupée presqu’
entitrement par le cadre génital, arrondi. Toutes les plaques sont simplement
granuleuses, sans sculpture. Le rostre est conformé comme chez //. (L.) chevreuai.
Les pattes sont longues, a articles cylindriques, avec le tarse fortement recourbé en
dedans, surtout 4 la 4° paire, et completement dépourvu de gouttiere onguéale; la
pitce médiane des griffes se termine par un appendice bidenté énorme. Les griffes sont
presque droites jusqu’a la dent accessoire, et ne portent qu'un peigne court occupant le
milieu de la branche droite, 4 dents souvent usées ou brisées. Le 3° article des pattes
est un peu renflé; le 4° est fortement échancré asa base interne. (Dimensions: voyez
plus loin.) Dix specimens, males, femelles et nymphes.

“Cette belle espece, la plus grande du sous-genre Leptospathis, est dédiée a
S. A. 8. Albert 1°, Prince Régnant de Monaco.”

La sous-espece des mers antarctiques dépasse encore en dimensions le type du
Nord: nous la décrirons sous le nom suivant :

1Trouessart, Bull. Soc. Zool. de France, 1902, pp. 67, 68.

4 DR. E. L. TROUESSART.

LEPTOSPATHIS ALBERTI ANTARCTICA.

Trés semblable au premier abord au type, mais en différant par sa taille plus
grande et des proportions un peu différentes, comme l’indique le tableau suivant: ~

Dimensions:

|
|
|

| L, Alberti typica. \L. Alberti antarctica

Trone;ayecile rostres =. se 1100 p | 1200 p
Tronc sans lerostre. . . . . 900 | 1000
Rostre (longueurdu) . . . . 200 200
1 paire de pattes . . . . . 780 890
2° 2 720 780
3 2 he bot ech Yo 760 800
4° BON oe Ge a 800 | 900
Margenridnitronc® | 15 = 0 ae) are 450 | 530
Largeur du 3° article (1° paire). | 80 60
1° et 2° articles dela le paire . . 120 120
Gem) 5 Mose a) eh cal ton el lO 250
Boa Ge Sea kaa oe eee 100 120
De A a) oe Sole eee 200 250
6° ee eee io eS te Ge. 0 150 150

N.B.—Ces dimensions varient un peu d’un individu a Vautre.

La comparaison de ces chiffres montre que la sous-espece antarctique differe
du type arctique par: 1° une taille un peu supérieure; 2° des pattes relativement
plus longues et plus gréles (notamment le 3° article de la 1° paire) ; 3° des proportions
un peu différentes des pattes: ainsi, tandis que les 1%, 2° et 6° articles de la 1° paire
sont sensiblement égaux dans les deux formes, le 4° et surtout le 3° et le 5° montrent

une différence notable. Cette patte s'est done allongée surtout dans sa partie
moyenne.

DESCRIPTION DE LEPTOSPATHIS ALBERTI ANTARCTICA.

Trone.—-Ovoide, largement arrondi en avant; le bord du camérostome presque
droit transversalement, conique en arriére, ot. le tubercule anal forme un petit cdne
tronqué nettement distinct ; les flanes portent une forte échancrure au niveau de
linsertion de la 2° paire de pattes, une autre beaucoup moins marquée & insertion
de la 4° paire.

Face dorsale: plaque de lépistome plus large que longue, arrondie en demi-cercle
en arriere, son bord postérieur dépassant un peu le niveau de la 2° paire. Plaques
oculaires irrégulitrement triangulaires, & bords arrondis, saillantes sur leur bord antéro-

* Avant la compression dans la préparation. Aprés compression, on trouve 500 et 600 » environ.

ACARI. 5

externe, qui porte deux lentilles oculaires. Plaque notogastrique en ovale allongé,
largement séparée des autres, ne couvrant que le milieu de la région, son bord
postérieur atteignant la base du tubercule anal.

face ventrale: plaque sternale large, s’étendant latéralement jusqu’a la base des
deux premitres paires de pattes, son bord antérieur fortement échancré en demi-cercle
par louverture du camérostome, arrondie en arriére, et ne dépassant pas la 2° paire de
pattes. Plaque ventrale courte et peu large, mais se prolongeant sous le céne anal et
presqu’enti¢rement occupée par le cadre génital, qui est grand, arrondi, un peu ovalaire
chez la femelle ; plus large, circulaire, chez le male. Chez la femelle, il porte six paires
de poils insérés en-dedans du cadre; chez le male il présente une double couronne de
poils. Plaques coxales grandes, triangulaires. Téguments tres finement plissés dans
Yintervalle des plaques et portant, sur les flancs, des poils assez forts, savoir: un en
avant de la plaque oculaire ; trois en avant de la 3° paire de pattes ; deux en avant de
la 4°; un A la base du cone anal.

Rostre—A base hémisphérique formant calotte 4 la face dorsale, plus large que
longue. Palpes deux fois plus longs que la base, et dépassant Vhypostome de la
longueur du dernier article ; présentant la forme caractéristique du G. Leptospathis,
eest-a-dire paralléles, a 3° article faiblement fusiforme, plus long que la moitié du palpe
tout entier, le 4° trois fois plus court, le 5° et dernier un peu plus long, conique avec
une petite pointe gréle. Un poil rigide, long, et gréle, dirigé en avant 4 lextrémité
interne du 3° article.

Pattes.—Décroissant de longueur dans l’ordre suivant; 4°, 1°, 3°, 2. — 1°° paire:
accolée au rostre, longue et gréle (voyez les dimensions au tableau, page 43); les
deux premiers articles courts, piriformes, le 3° allongé, faiblement renflé 4 son
extrémité ; le 4° assez court; le 5° aussi long que le 3°; le 6° (tarse) plus gyréle, un
peu recourbé en dedans, sans échancrure onguéale, terminé par des griffes longues,
faiblement recourbées, ne portant de peigne que dans la partie médiane (ce peigne a 8
&% 13 dents au plus). Piece médiane des griffes grande et forte, bidentée. Une
touffe de cirrhes en-dessous de l’extrémité du tarse. Les poils que portent les

pattes sont tous gréles. — 2° paire: semblable & la 1°, mais plus courte et un peu
plus gréle; le 3° article, notamment, et le 5° sont manifestement plus courts qua
la 1° paire. — 3° paire: insérée un peu en arritre du milieu du tronc; plus longue

que la 2°, le tarse plus allongé. — 4° pare: insérée tres en arritre, la plus longue de
toutes, le tarse plus fortement recourbé en dedans, le 5° article portant sur son bord
interne trois poils & base en chandelier, c’est-d-dire insérés sur une petite saillie ep
forme de bobéche. La pice médiane du tarse beaucoup plus forte qu’a la 1° paire.

Différences seauelles.—La femelle ne differe du mile que par la forme de Porgane
génital, la disposition et le petit nombre des poils qui l’entourent.

Couleur.—Cette sous-espece est d’un brun plus foneé que le type du Nord, ce qui
peut tenir au genre de nourriture.

Dimensions,—(Voyez le tableau, page 43.)

6 DR. E. L. TROUESSART.

Nymphes.—De forme elliptique ou naviculaire, les pattes relativement plus
courtes, surtout celles de la 4° paire (d’apres le type du Nord).

LEGENDE DES FIGURES.
PLANCHE.

Fic. 1. Leptospathis alberti antarctica, Trt., adulte ? , face dorsale x 90.
2. Le méme, rostre, face ventrale x 450.

3. Le méme, extrémité des chéliceres x 660.

4. Le méme, extrémité du tarse et griffes de la 4° paire X 660.

5. Le méme, organe génital (femelle) x 350.

4

Antarctic (Discovery) Exp.

Aut.del. West,Newman lith

qT, epbospathis Alberti antarctica.

CHAETOGNATHA.

WITH A NOTE ON THOSE COLLECTED BY H.M.S. ‘CHALLENGER’ IN
SUBANTARCTIC AND ANTARCTIC WATERS.

By G. Hersert Fowter, B.A., Pa.D., F.LS.

J

(1 Chart.)

I.—THE COLLECTION OF THE ‘DISCOVERY.’

THE specimens mentioned below include all those taken south of 40° S., a parallel
selected to include what appear to be the eritical temperatures which separate a
temperate and subantarctic plankton from truly Antarctic forms. The material was
preserved in alcohol, and was mostly in fair condition, but presented the usual
disadvantages which attend upon the use of this reagent for Chaetognatha.

Only three species were represented. The tables of formulz,*
species, serve to show the relation between the more obvious variations which occur in

given under each

these southern specimens and those in specimens from other localities. In these tables
the first column of figures gives the total length in millimetres (including the tail fin) ;
the second, the length of the tail expressed as a percentage of the total length; the
third, the number of jaws; the fourth, the number of anterior teeth (or of the only rew
of teeth in the case of Arohnia); the fifth (when present), the number of posterior
teeth.

SAGITTA HEXAPTERA.

Sayitta hexaptera, D’Orbigny, Voyage dans Amérique méridionale. Tome Y., 3° partie; Mollusques,

p. 143. (1835-1843.)

The species was represented by numerous specimens. They agreed with typical
heraptera in almost every one of such diagnostic features as they had retained, the
exceptions being that the anterior fin appeared to extend slightly further forward than
is usually the case (due possibly to imperfect preservation), and that the first (newest)
jaw hardly showed the usual ridge and bay just below the tip; the extent to which

* The latest papers on Chaetognatha, summarising the distribution and literature of the group, are: “ Biscayan
Plankton collected during a cruise of H.M.S ‘ Research,’ 1900, Part III.—The Chaetognatha”’; Transactions of

the Linnean Society, 2nd Series, Zool., Vol. X., pp. 55-87; and ‘‘ Reports of the ‘Siboga’ Expedition. Mono-
graph XXI., The Chaetognatha”’ (Leiden, 1906).

VOL. III. :

2 G. HERBERT FOWLER.

this latter is developed, however, varies much in specimens from other localities.
There seems no reason to regard these two points as sufficiently important to justify
the separation of Antarctic specimens from D’Orbigny’s species,

Formule, based on thirty-four specimens :—

75 13 7-8 4-5 8-9
55 15-18 Uf A=) 7-9
51 2 8-9 5 7
50 214 8 if 7
47 14-17 6-8 4—5 7-9
43 13-15 7-8 3) 5-7
39 1145) 8-9 4 6-7
38 15 8 i) 6
34 1k} 8 3 5-6
33 18 7-8 4-5 6-7
231 y 9 4 if
30 16 8-9 4—5 7
29 16-17 7-9 4—5 4-7
28 19-21 7-9 4 5-6
27 18 9 3 3-4
y 19 8-10 3-4 4—6
24 16-20 8—9 4 4—5
ZB DD, 10-12 3—4 i)
21 eal 10 4 3
19 Frill 7-9 2 3
We 20 9 3 2,
16 [eca. | 2 7 4 5
15 23 8-9 3 3

SAGITTA SERRATO-DENTATA.
Sayitta serrato-dentata, Krohn, Archiy fiir Naturgeschichte xix. (18538), p. 272.

As will be shown below, this is not a truly Antarctic form. It appeared to be
male-ripe at about 12 mm. of total length; no really female-ripe specimens occurred.
Formule, based on 8 observations :—

13 27 7 6 10
12 39 if 5-6 tlallil
11 36 7 4-5 9-10
10 40 Ul 4. 6
9 2 7-8 4 7

CHAETOGNATHA.

we)

KROHNIA HAMATA.

Sayitta hamata, Moebius, Zoologische Ergebnisse der [‘ Pommerania’] Nordseefahrt: Vermes. Jalres-
bericht der Commission zur wissenschaftlichen Untersuchung der Deutschen Meere, Jahrgang
II., III. (1875), p. 158; pl. iii, fig. 13-16.

Quite typical specimens of this species were captured, sometimes in large

numbers, but the majority were small and immature specimens, under 15 mm.

Formule, based on 21 specimens :—

31 24 7-8 19-20
26 we 8-9 Ld
all 18-28 6-9 12-23
c. 20 2 8 13
9 26 9) 14-16
7, 23-29 7-9 6-11
Caplio 26 7-8 6-10
14 25 8 4
ial Dil 8 5-6
9 30 8 4

The occurrences of these species at the various stations are presented below in
tabular form.

Date. Position. | Hote, | Depi | ,Sesitte, | crmioden-| robula | Temperature
Teemoetgoie. . . | 40°19'S,, 32°97'H. | — | Oo |] -1 20 = 12° ator
Oct. 22,1901. . .,| 45°00'S., 40°57’E. | -- 0 l 9 | = 4° 4
Octeza 1900 5 2 . | 45° 08'S., 44°47’ H. — 0 10 } — 4° 4
Novan, 1901. = «. | 48° 44'S., 100° 16’. | — 0 1] YB to 34
Novella tgOl. ~ . | 51°20'S., 126° 23'E. | — 0 2 l 6
Noy. 21, 1901. 562 31/S., 156° 19’. | — | 0 1 ibaa
Novas ION. = = | 56° 31'S., 156° 19’. | — 0 11 13 3° 6
Novas, l902. . - | 77° 49'S.. 166° 00'H. { 8 1 = —1°'9
Deei,1902 . . «| : ' 7 1 - ~- -1°9
Weerseigo2 . . . a 3 4 6 1 = a —=ii6
Mee4, 1902. .- . | > Wie 6 l =1n6
Mare2in 903. . - | ef ae | 4 6 ] -1°9
Marea. 1903; . - - a | 4 5 I = 1°49
Mar. 27,1903. . . - esa | 10. as =I9
May5,1903 . . . ee se 8 10 2 —1°9
May 6, 1903 5 cs] | 5 1 I -19
May 951903 . . . | | 5 3 —1°9
Mays, 1908. . . | ae BF | 8 10 2 : —-1°9
May 16,1903. . . Pace fa | { 5 1 1 -1°9
May 2951908. . . : = | 4 D 3 —1°9
June d,1903.. . . | 8 10 ) 1 -V9
June 28,1903. . . | 8 10 — 3 —2°0
Wulvatsst908. . .-| & ne 8 10 2 3 —2°0
Anes. 1908. . « i; a | 8 10 | 1 2 —1°9
Ano 908. . « a a | 8 10 | 1 — ( -1°8
Aug. 27, 1908. : 43 ay. 8 10 l 3 —1
Sept. 9, 1903 . 8 btm. | — 1 ke
Sept. 18, 1903. | 8 10 | l ; =178
Noy. 2, 1903 . | 2 12 10 : 2 —1°8
June 21,1904. . . | 56°12'S.,136°18'W. | — 10 3 60 30
June 24,1904. . . | 58°49'S., 194°48'W. | — 5 3 159 Pale
June 25,1904. . . | 59°19'S., 120°24’W. | — 5 1 — 71 2°'2
June 28,1904. . . | 59°34'S.,106°28'W.| — | 5 | 2 90 2° 2
July 1,1904 . . . | 55°44’S, g5c4s'w.| — | 5 | 38 = 61 5° 3
ee ——EE——e——E——EeE——_——eeE

4 G. HERBERT FOWLER.

IL—THE COLLECTION OF H.M.S. ‘CHALLENGER’ IN ANTARCTIC
AND SUBANTARCTIC WATERS.

Some six years ago Sir John Murray, K.C.B., kindly sent to me the
Chaetognatha collected by H.MLS. ‘Challenger’ in 1873-1876. Captured at a date
when methods of preservation (especially of plankton) had not been so carefully
studied as of later years, and having lain for thirty years in alcohol, the specimens
are, naturally enough, by no means in a condition to allow of a general report on the
collection. So far, however, as could safely be done, I have attempted to identify
the more characteristic species taken in nine hauls at the surface, which lay either
in the cruise to the Antaretic or towards the subantarctic Patagonian region. These
nine were the only hauls available in what may be termed the critical latitudes. They
were studied mainly with the idea of finding approximately the northern limit of
K. hamata at the surface, and the southern limit of S. serratodentata, the former
being bipolar in the strictest sense, the latter being believed to be tropical, temperate,
and subpolar only. They appropriately supplement the collection of the ‘ Discovery.’

A considerable number of the specimens were in a hopeless condition ; only those
are listed here of the identification of which the writer felt reasonably certain. As to
the records of K. amata and S. serratodentata, there can be practically no doubt, but
S. hevaptera is less certain, and S. Zetesios (?) least certain of all.

The species noticed in these hauls of the ‘Challenger’ were the same as those
taken by the ‘ Discovery, with one addition.

SAGITTA HEXAPTERA, dOrbigny.
Formule, based on thirteen specimens :—

31 16 10 5) 6-7
26 17 10 5 6
25 16 9 4 5-6
Polk 13-16 8-10 A—9 A—}5
18 21—22 8-11 4 5-7
16 18 9 3 2
15) 20 10-11 3-5 2-6
11 25 9-10 3 2
10 2 8-10 3 2-3
SAGITTA SERRATODENTATA, Krohn.
Formule, based on thirty-one specimens :—
16 31 6-7 5 9
5) 26-33 7-8 4—5 6—LO
14 27=32 7-8 3-6 8-12
3 27-30 6-7 5-6 9-14
12 25-33 7 4-5 7-13
a 27=32 7-8 3-6 8-12
10 25-30 6-7 3-6 7-13
9 27-33 6-7 2—4 4-8
8 25-34 7 3—6 3-10

CHAETOGNATHA. 5

SAGITTA ZETESIOS.
Sayitta zetesios, Fowler, Transactions of the Linnean Society, 2nd Series, Zoology, x. (1905), p. 67.

To this species I refer, with very great hesitation, three specimens from tempera-
tures below zero (Centigrade). The numbers, the size, and the shape of the teeth and
jaws agreed fairly well with those of specimens already described, but the specimens
were in far too battered a condition for the determination to be reliable.

Formule :—

12 [ca.] ? 9 6 13-14
10 30 8-9 5 Hie12
9 33 9 5 8-9

KRoOHNIA HAMATA, Moebius.

These specimens were quite unmistakable. In some of the younger specimens
the older jaws showed the characteristic sagination figured by Strodtmann and
myself in northern specimens.

Formule, based on twenty specimens :—

17 Ai 7-8 8-9
15 20-23 7-9 7-13
14 25 8 26
13 26 6-7 9
12 25-29 7-9 7-10
Hal 22-27 6-9 ? 4-12
10 30 7-8 2 3-7

The actual observations are as follows. They have been arranged in order of
decreasing temperatures, which agrees, except for a single entry, with the order of
increasing latitude.

| Sagitta

Station. Date. | Position. TGentigrade, | hamata, | 8?tatoden-| nerapters

299 | Dec. 14,1875 | 38° 31'S. 74° 43’ W. | 15°to16°6 | — 1 7 =
302 | Dec. 28,1875 .| 42° 43"8., 82°11’ W. | 12°7 11 17 6 =
308 | Dec. 30,1875 .| 45° 31'S, 78°9'W.| 12° 2 4 a7 4 =
159 | Mar.9 &10,1874| 47° 25'S., 130° 29’ E 10° 5 24 1 3 =
146 | Dec. 29,1873 .| 46° 46'S. 45°81’ E. 6° 1 80 Fa 2 at

nr. 150 | Feb. 3,1874. .| 52° 4'S., 71° 22' E. 2° 7 4 =
156 Feb. 26, 1874 ~ .} 62° 26’ S., 95° 44’ BE. Oi 9 —
154/5 | Feb. 21,1874 .| 64° 27'S., 90° 48' E.| —0°3

1
153, Feb. 14,1874 .| 65° 42'S., 79° 49’ E. —-1°6 18 = 1

6 ; G. HERBERT FOWLER.

I1L—DISTRIBUTION.

The occurrence of these species in really polar waters is of considerable interest.

The record of Avohnia hamata as a truly “ bipolar” species is thus completed ;
it ranges from 81° 30! N. (Rémer and Schaudinn) to 77° 49'S. ; it is both epiplanktonic
and mesoplanktonic at high latitudes with low surface temperatures, but in tropical and
warm temperate seas is known only from the colder strata of the mesoplankton.
While, horizontally speaking

o>?

it appears to be cosmopolitan, and is fairly eurythermal,
it has not been recorded definitively from a higher temperature than 12°7° Cent.
(‘ Challenger’ Collection).

As to Sagitta hevaptera, the captures of both ‘ Discovery’ and ‘Challenger ’
complete its record as a ‘‘ pantothermal”’ species, that is to say, one living at practically
every known sea-temperature, from about 29°C. to — 2° C. ; and asa truly cosmopolitan
species, ranging from Spitsbergen in the north to the ‘Discovery's’ winter quarters
in the south, and from every sea from which Chaetognatha have been recorded.

Sagitta serratodentata, on the other hand, failed at the colder stations of both
‘Discovery’ and ‘ Challenger’ ; its minimum record f has now been reduced to 4°6° C.,
the lowest temperature at which it had been taken previously being between 6°6° and
12°2° C. at the Falkland Islands. Its definitive temperature limit in the Northern
Hemisphere is at present 12°2° C., but in view of the ‘ Discovery's’ captures it may
possibly prove to extend somewhat further north than its present record of lat.
60° 12'N. At any rate, it seems to be clear that it is not “ bipolar,” although
subantaretic and north-temperate.

The southern captures of hevaptera, serratodentata, and hamata, from all-sourees, |
have been plotted on the appended circumpolar chart, together with the mean annual
surface isotherms of 12° and 6° C., as calculated by Dr. Schott. The former appears
to indicate approximately the northerly limit of hamata as an epiplanktonic form, the
latter similarly to indicate the southerly limit of serratodentata.

The definitive temperature limits given in the ‘Siboga’ Report already cited
require amendment as follows :—hevaptera, lowest temperature, — 2° C. ; serratodentata,
lowest temperature, 4°6° C.; hamata, highest surface temperature, 12°7° C., lowest
temperature, — 2° C.

+ This record is, however, of a single specimen, and the species had failed at the two previous stations

(compare p. 8 above). It is therefore possible that we are dealing merely with an isolated specimen, which had
drifted beyond its natural limits.

NEMATODA.

Von Dr. v. Linstow.

(1 Plate. )

LEPTOSOMATUM AUSTRALE.
Gesammelt bei Hut Point, September 24th, 1902.

Diese Art ist die grisste aller bekannten freilebenden Nematoden; das Weibchen
erreicht eine Linge von fast 50 mm.; die Farbe der Spiritus-Exemplare ist gelblich-
braun. Der Kérper ist lang gestreckt und schlank; die Breite verhialt sich zur
Linge wie 1 : 82-88; das Kopfende ist stark verdiinnt, das Schwanzende nur wenig
und in beiden Geschlechtern abgerundet. Die Cuticula ist sehr dick, 0°0156 mm.
breit, und mehrschichtig, die iiussere Lage fiirbt sich schwach durch Borax-Carmin,
die innere nicht; eine Querringelune fehlt; am Kopfende trigt die Cuticula 14
Lingsreihen kurzer, breiter Dornen oder Borsten, die theils senkrecht von ihr abstehen,
theils gekriimmt und mit der Spitze nach vorn gerichtet sind; nach hinten werden
sie immer sparsamer und verschwinden etwa 1°2 mm. vom Kopfende entfernt ganz,
am Schwanzende treten sie in iihnlicher Weise wieder auf; sie stehen einzeln oder
zu zwelen oder dreien neben einander.

Das Kopfende ist gerade abgestutzt ; 0°023 mm. vom Scheitel entfernt steht ein
Kranz von 10 Borsten oder Stacheln, in den Seitenlinien je eine einfache, in den
Submedianlinien doppelte ; dicht dahinter bemerkt man jederseits in den Seitenlinien
ein Seitenorgan ; 0°25-0°28 mm. vom Scheitel finden sich 2 dunkle Augentlecke.

Von der Subcuticula erheben sich nach innen 4 Lingswiilste, ein dorsaler, ein
ventraler und zwei laterale ; im Kopf- und Schwanzende sind sie miichtig entwickelt,
im langen, mittleren Kérpertheil aber wird ihre Hohe sehr verringert ; ihre Méachtig-
keit ist hier nur 15-2 mal so stark wie die Dicke der Cuticula. Der Dorsalwulst
ist am schmalsten, und wird in der Mitte des Kérpers wie der Ventralwulst zu
einem schmalen, die Muskulatur trennenden Kamm reducirt ; Dr. de Man™ findet in
seiner vortreftlichen Arbeit iiber die auf der Reise der “ Belgica” gefundenen Nematoden
bei den verwandten Arten Thoracostoma setosum vy. Linst. gar keine Dorsal- und
Ventralwiilste. Die Seitenwiilste sind stark entwickelt und nehmen jeder etwa
j;-1 der Kérperperipherie ein; sie bestehen aus einem dorsalen, einem mittleren
und einem ventralen Theil und sind iiberall mit Zellen durchsetzt, welche grosse,
theils blasse, theils schwarz pigmentirte Kerne und vielfach Kernkérperchen

* de Man, Résultats du voyage du S. Y. Belgica en 1897-1899, Zoologie, Nématodes libres, Anvers, 1904,
pag. 26, tab. vii., fig. 8 j.

2 DR. V. LINSTOW.

enthalten. Der dorsale und ventrale Theil werden von gestreckten kolbenférmigen
Stringen gebildet, wie sie im Querschnitt erscheinen, auch die in ihnen legenden
Zellen sind linglich rund, wiihrend die Zellen des mittleren Theils meistens kugelrund
sind. Der Ventralwulst ist stiirker als der dorsale; er wurzelt auf der Subcuticula
mit schmaler Basis und verbreitet sich nach innen, aber nur im Kopfende; im
evossen mittleren Kérpertheil ist er nur eine schmale Leiste ; ganz vorn, in der Niihe
der Augenflecken, sind alle 4 Liingswiilste geschwunden und die Muskulatur bildet
einen zusammenhiingenden Ring auf Querschnitten.

In der Leibeshéhle, zwischen den Muskeln und den Lingswiilsten einerseits
und dem Verdauungstract und den Geschlechtsorganen andererseits legen zahlreiche
freie Zellen, eiformig oder kugelrund, mit grossem, theils blassem, theils schwarz
pigmentirtem Kern, oft mit Kernkérperchen, welche den Zellen der Seitenwiilste
durchaus gleichen ; besonders zahlreich und dicht gedringt finden sie sich vorn und
hinten im Kérper, im Kopf- und Schwanzende, besonders grosse, die 0°048 mm.
lang und 0°044 mm. breit sind, sieht man 0°30-0'48 mm. von einander entfernt,
hinter einander liegen; die durchschnittliche Grésse ist 0°026 mm. und die des
Kerns 0°014 mm.

Die 4 Liingswiilste theilen die Liingsmuskeln in ebenso viele Felder; im Kopf- und
Schwanzende ist die Muskulatur miichtig entwickelt, bis 0°039 mm. dick, wiihrend sie
im iibrigen Korper nur 13-2 mal so dick ist wie die Cuticula; am minnlichen
Schwanzende stehen parallele Muskelziige, die schriig von vorn und der dorsalen nach
hinten und der ventralen Seite ziehen.

Im Kopfende sieht man 2 dunkle Augenflecke, die nicht in der Cuticula liegen,
sondern der Aussenseite des Oesophagus eingepflanzt sind; sie sind rothbraun und
stehen 0°15 mm. vom Scheitelpunkt entfernt; sie finden sich aussen von den dorso-
lateralen Schenkeln des dreischenkligen Oesophagus-Lumen und bestehen aus je einer
Linse, die innen von einem Pigmentbecher umfasst wird. Zur Perception von Bildern
kénnen diese unter der dicken Cuticula und der starken Muskulatur legenden
Sehorgane wohl nicht dienen, wohl aber, wie bei /pibdella, wo 4 Ocellen mitten im
Gehirn liegen, zur Unterscheidung von Hell und Dunkel. Auch de Man * findet bei
Thoracostoma setosum v. Linst. und Thoracostoma antarcticum v. Linst. die Augenflecke
an der Aussenseite des Oesophagus, aber nicht dorsolateral, sondern, wie es scheint,
lateral.

Der Oesophagus nimmt beim Miinnchen ,,, beim Weibchen 5, der ganzen
Thierliinge ein; das Lumen ist dreischenklig und der eine Schenkel ist, wie in der
Regel, ventral gerichtet ; Lingsmuskelziige, die radiir gestellt sind, durchziehen das
ganze Organ und dienen durch Erweiterung des Lumens zum Ansaugen von Nahrung ;
3 lange Driisen, 1 dorsal, 2 ventrolateral, durchziehen den Oesophagus der ganzen
Linge nach; am Kopfende bilden sie erweiterte Ausmiindungsgiinge, die 0°12 mm.
vom Scheitelpunkt in das Oesophaguslumen einmiinden.

* Op. cit. pp. 31 u. 39, tab. x. fig. 9, f.

FREE NEMATODES. 3

Der Darm besitzt eine dicke Tunica propria ; das Epithel wird von breiten Zellen
gebildet, die eine Liingsstreifung zeigen und einen bald blassen, bald schwarz pigmen-
tirten Kern enthalten.

- Ein Nervenring umgiebt den Oesophagus 1°18 mm. yom Kopfende, etwa an der
Grenze von dessen 1. und 2. Viertel: seine Dicke betriigt 0°018 mm. und er enthalt
ovale, 0°0156 mm. lange und 0°0104 mm. breite Ganglienzellen.

Leimdriisen, welche bei anderen freilebenden Nematoden am Schwanzende miinden,
fehlen hier ganz, der Raum hinter dem Anus ist von Zellen der Seitenwiilste erfiillt.

Das Méannchen wird 37°7 mm. lang und 0°46 mm. breit ; der Schwanz macht +4,
der ganzen Liinge aus ; 0°26 mm. vor der Cloakenéffnung in der Mittellinie miindet die
Prianaldriise in einer rundlichen Vorragung des Kérpers, die eine becherartige Offnung
triigt ; in diese miindet die kolbenformige, 0°16 mm. lange und 0°034 mm. breite
Driise ; die beiden Cirren sind sichelformig gekriimmt und in der Mitte verdickt, ihre
Liinge betriigt 0°22 mm.; dorsal von ihnen liegt ein 0°18 mm. langer, stabformiger, an
beiden Enden abgerundeter Stiitzapparat; die Hoden erfiillen die hinteren 4 des
Ko6rpers ; Papillen fehlen ganz.

Das Weibchen erreicht eine Liinge von 49°5 mm. und eine Breite von 0°56 mm. ;
das Schwanzende nimmt 5}, der ganzen Linge ein; auch hier sind die Geschlechts-
organe weit nach hinten geriickt: die vordere Kérperhiilfte beherbergt sie gar nicht ;
theilt man die Liinge des Kérpers in 10 gleiche Theile, so legen Uterus und Ovarien
im 6.-8. Zehntel; die Vulva miindet etwa an der Grenze des 2. und 3. Drittels, sie
theilt den Kérper im Verhiiltniss von 11 : 6; die Kier liegen im Uterus in einer Reihe ;
sie sind gross und wenig zahlreich ; die gréssten, welche der Vulva zuniichst legen, sind
0°79 mm. lang und 0°31 mm. breit.

Es fragt sich, welche Function die Seitenwiilste und die freien Zellen haben
kénnten ; zur Nahrungsaufnahme dienen sie offenbar nicht, da die Cuticula zu dick ist
und Oesophagus und Darm eine normale Ausbildung zeigen; ein Absonderungsorgan
kénnen sie auch nicht sein, da ein Ausmiindungsgang nach aussen fehlt; sie werden
also eine Bedeutung fiir den inneren Stoffwechsel haben und halte ich es fiir wahr-
scheinlich, dass sie die Function von Lymphdriisen besitzen.

Die parasitischen Nematoden habe ich friiher* eingetheilt in Secernentes,
Resorbentes und Pleuromyarii.

Secernentes sind Nematoden mit voll entwickeltem Oesophagus und Darm, welche
schmale und hohe Seitenwiilste besitzen, die ein Liingsgefiiss enthalten ; die Gefiisse der
heiden Seiten vereinigen sich vorn in der Gegend des Oesophagus zu einem, das ventral
im Porus excretorius ausmiindet ; die Seitenwiilste scheinen die Function von Nieren
zu haben; die Arten leben im Verdauunestract ihrer Wirthe.

Resorbentes wurden Nematoden mit breiten und niedrigen Seitenwiilsten genannt,
denen ein Gefiiss und ein Porus fehlt; die Arten leben uie im Verdauungstract der
Wirthe, sondern in oder an anderen inneren Organen, oft fest von Bindegewehe

* Arch. f. mikr. Anat. xlix. (1897), p. 620.

VOL, Ill, Z

4 DR. V. LINSTOW.

umwachsen ; die Ernihrung erfolet hier offenbar durch Aufsaugung seitens der Seiten-
wiilste durch die Cuticula hindurch.

Pleuromyarae haben statt der Seitenwiilste Muskeln in der Seitenlinien.

In dieses System passen die freilebenden Nematoden nicht hinein, fiir die ich
Abtheilung der

Adenophori aufstellen michte. Dieselben besitzen schmale Seitenwiilste mit
gekernten Zellen und ohne Liingsgefiiss, welche als Lymphdriisen zu functioniren
scheinen ; wenn ein Porus excretorius vorhanden ist, so ist er die Ausmiindung einer
Ventraldriise.

ERKLARUNG DER ABBILDUNGEN.

c, Cuticula; a, Augenfleck; , Nerv; 0, Oesophagus; ¢, Darm; m, Muskeln; dr, Dorsal- ;
vt, Ventral-; /, Lateralwulst oder -Feld ; 2, freie Zellen; s, Seitenorgan ; p, Priianaldriise ; dm, Driisen-
miindung ; v, Vagina; uv, Uterus ; 4, Hoden.

Fig. 1.—Miinnchen, m. transversale Muskeln am Schwanzende. Veregr. §.

» 2.—Weibchen. Verer. +.
», 3.—Kopfende. Vergr. 19°.
Fics. 4-8.—Querschnitte.
Fig. 4.—Oesophagus mit der Einmiindung der Driisenausgiinge in das Oesophagus-Lumen. Vergr. 142.
55 5.—Oesophagus mit den Augenflecken. Verer. 172.
», 6.—Oesophagus-Gegend. Vergr. 19°.
5, 7—Mittlerer Korpertheil, Theil der Korperwandung in der Seitenlinie. Vergr. °°.
5, 8.—Querschnitt des Weibchens hinter dem Uterus. Vergr. 29°.
» 9-—Liingsschnitt vom Minnchen durch die Priianaldriise, parallel mit derselben verlaufen
transversale Muskeln. Vergr. 172.
» 10.—Cirrus und Stiitzapparat. Vergr. 142.

Aut.del. West,Newman lith.

Nematodes.

Antarctic (Discovery) Exp.

CHESTODA.

By Arruur E. Surpriey, M.A., F.R.S.,
Fellow and Tutor of Christ’s College, Cambridge, and University Lecturer in the
Advanced Morphology of the Invertebrata.
(1 Plate.)

THE only Cestodes brought back by the naturalists of the ‘Discovery’ were three species,
all of which were found living together in the stomach of Ross’s Seal, Ommatophoca
rossi. The three differed markedly in size, in the shape, number and relative pro-
portions of the proglottides, so that there is no doubt that we are dealing with three
distinct species, and not with different stages in the growth of members of one species.

All the specimens were pickled in Perenyi’s fluid, and arrived in an excellent state
of preservation. ;

The largest of the three species is undoubtedly the same animal which Baird, in
1853, named Bothriocephalus antarcticus.

I give below Baird’s diagnosis, and then add a few remarks upon the anatomy of
the specimens.

DIBOTHRIOCEPHALUS ANTARCTICUS.

Bothriocephalus antarcticus Baird, Proc. Zool. Soc. London, 1853, p. 25, Annulosa, pl. xxxi., fig. 4 and da.

‘* Head conical, elongated, smooth, with two lateral opposite fossettes. At the lower
margin of each fossette there are two small rounded projecting lobes. Body rounded ;
from the neck some way downwards it is quite round or cylindrical, and the articulations
are very numerous and very small, appearing like mere ridges across. Lower down, the
body becomes flatter and the joints larger and more developed; lower margin thin.
An impressed line runs along the centre of the body through its whole length. Length,
about 9 inches; greatest breadth of body, about 3 lines.”

Baird’s specimens measured about 9 inches, say about 23 cms. Most of the
specimens at my disposal were just under 10 cms., but a couple, apparently young,
barely measured 3 cms. The specimens were obviously immature, only in the
most posterior of the longer examples were uteri and ova to be found, and the
latter in very small numbers; I am inclined to think also that these specimens
had contracted when being killed, the anterior end of the body not being so
rounded as Baird describes. The greatest breadth is 7 mm. in the largest specimen.

Z 2

2 ARTHUR E. SHIPLEY.

The body tapers anterioly, and to a sheht extent posteriorly. There is no true
neck, the proglottides beginning immediately behind the head; they are at. first
extremely short from before backward, a feature they retain, though to a lesser degree,
even at the hinder end, where it takes some three to measure a millimetre. The
posterior edge of each proglottis overlaps the succeeding one to a marked extent.

The head is conical, 8 mm. in length and 3 mm. in breadth posteriorly ; anteriorly
it lessens to a bluntly pointed apex. Dorsal and ventral le the two suckers. These
suckers are deep, with cleanly cut edges, for the most part curled in (fig. 7), and in
all cases enwrapping some foreign substance, perhaps a portion of the mucous
membrane of the host.

The impressed line running along the whole body, referred to by Baird, is only on
the ventral surface, and is due to the median opening of the reproductive organs and
of the uterus.

The nervous system consists of two very conspicuous nerve cords, which lie parallel
with the longitudinal excretory canals, and about one quarter the distance of the latter
from the edge of the proglottis outside the canal. The cords fuse together in the head.

The longitudinal canals of the excretory system are also conspicuous, and are
surrounded by thick walls; they break up into an anastomosing tangle of ductules in
the head. There are also small canals which lie close under the surface at the edges of
the proglottides, usually two at each side (fig. 2), but they also break up from time to
time into twisting branchlets. The overhanging edges of the proglottides, especially of
the posterior ones, are very richly supplied with water-vascular tubules. It is possible
that these may have a certain hydrostatic action, and serve to erect these free edges
when fluid is directed into them.

The confused meshwork of muscles in the head straighten themselves out in the
neck and fall into regular rows. Of these there are six or seven dorsally and six or seven
ventrally (fig. 2), but at the sides the rows tend to merge and lose their distinctness.
Each row is separated from the next by very clear and distinct connective tissne
fibrils running parallel with one another. The muscles in these rows consist of bundles
of various sizes containing from six or seven up to fifteen or twenty fibrils. Running
between every two or three of these bundles are some slight and radially arranged
connective tissue fibrils, which, with the concentric fibrils of the same nature, serve to
divide up the tissues into a series of little squares. No muscle fibres penetrate the
parenchyma within the central area, bounded at the sides by the nerve cords and
dorso-ventrally by the innermost layer of muscles.

The penis is conspicuous and very muscular, it opens in the anterior edge of the
proglottis just where it joins the one in front, and is concealed by the overlapping end
of the preceding proglottis. Close behind it opens the vagina, and behind this again the
uterus, all in the middle ventral line. There is a large vesicula seminalis.

The testes are scattered throughout the parenchyma of the central part. The
ovary is rather branching ; it lies towards the posterior end of each proglottis, is deeply

CESTODA. 3

stained and fairly conspicuous. The yolk-glands are widely scattered through the
peripheral parenchyma,

The uterus is not fully developed in our specimens, which must be rather immature.
It consists of few branches somewhat rosette-shaped. The ova are thin-shelled, and

measure 0°032 by 0°028 mm.

DIBOTHRIOCEPHALUS SCOTTI.

The second species of Dibothriocephalus found in the alimentary measured about
8cm. in length (fig. 3). One attained a leneth of 9em., but the other three or four
specimens were shorter. The number of proelottides is some 150. The head is
rounded, not at all conical, but like the amber mouthpiece of a Turkish pipe (fig. 4).
The slit-like grooves are dorsal and ventral. The head measures Imm. across, and
perhaps a little less from before backward. It is succeeded by a neck which, in
some specimens, is a little narrower than the head; in others about as broad. The
proglottides soon begin to be evident, but I do not think one can say there is no neck.
In this respect this worm differs from D. hians of Leptonyx monachus, Wagn., Phoca
barbata, Miill., and P. annellata, Nilss., which, in some respects, it resembles.

The proglottides are at first some five times as broad as they are long, but sooner
or later—and it depends upon the state of contraction of the worm when killed, how
soon or how late—the proglottides become square, with parallel sides, and they remain
square until the end. The posterior border is slightly thickened, and stands out at
right angles from the body. It practically does not, however, overlap the succeeding
proglottis.

The reproductive organs consist of numerous testes lying scattered superficially
through the proglottides ; the ducts of these presumably unite, though they could not
be seen, and open into an exceeding muscular penis, which in most cases is protruded
from the proglottis. The penis is situated in the middle line close to the anterior edge
of the proglottis. It bears no hooks. Close behind it opens the vagina, which makes
a coiling course backwards to where the two short oviducts from the ovary meet
it. The ovaries are two, somewhat pear-shaped; they lie each side, near the hinder
end of the proglottis behind the uterus, and are of fair size. A minute shell
gland is visible at the juncture of the oviducts. No tube entering the uterus
is visible.

The uterus is roomy, it opens on the ventral surface in the middle line, and about
half-way along the proglottis. The opening is circular. Just within this opening the
uterus forms a spherical chamber, which contains a fair number of ova. From this
chamber two or three lateral branches diverge, and these may be cut twice in one plane,
but in no sense is the uterus rosette-shaped.

The ova measure on an average 0°04mm. by 0°03mm., but the shape varies ; some

4 ARTHUR E. SHIPLEY.

are rather more rounded than those of the other two species, and some have more
pointed ends. The egg-shell is thick, with two clearly-defined contours.

The yolk-glands are easily recognised by their brown and glistening appearance.
Like the testes they are scattered, but they lie more superficially than the latter.
Although there is little differentiation between the medullary and the cortical regions, it
is plain that the yolk-glands lie in the cortex and the testes in the medulla.

The epithelium of this Cestode consists of unusually large cells, somewhat
columnar in shape, with their square outer ends pressed against the cuticle, and their
inner ends tapering (fig. 7). Their nuclei lie about, but not quite at, the same level,
near the inner end.

The parenchyma is loose and stains but slightly, it is traversed by but few muscle
fibres. The single pair of longitudinal excretory canals are conspicuous in sections, and
so are the nerve trunks. ‘There are numerous small excretory tubules running just
below the external epithelium.

I have ventured to dedicate this species to Captain Scott, the distinguished
commander of the Antarctic Expedition, though I am well aware that there is a certain
delicacy in doing so. Some people have a horror of Cestodes, and do not care to have
their names associated with them. ;

Dibothriocephalus scottiLeneth of specimens 9cem. and under ; number of pro-
elottides about 140; head rounded, diameter Imm.; average width of middle
proglottides about 2mm.; very short neck. Posterior edges of proglottides stand
out, but do not appreciably overlap the anterior end of succeeding proglottis ; uterus
spacious, with a few diverticula, not a rosette ; ova 0°04 by 0°03mm., with thick shell.

DIBOTHRIOCEPHALUS WILSONI.

This is a very attractive little tapeworm of few proglottides, which I have ventured
to dedicate to my friend Mr. E. A. Wilson, M.B., who was both a doctor and a zoologist
in the ‘Discovery. It somewhat resembles Krabhe’s Dibothriocephalus lanceolatus,
from Phoca barbata, but is much smaller.

The length varies from 4 to 5:5mm. In the larger forms the greatest breadth is
Imm., this occurs in the region of the last segment but one, or perhaps two. The
breadth of the head is a little less than 0°5mm., and its greatest length is about the
same.

The number of the proglottides varies from nine to thirteen or fourteen. There is no
neck, the first proglottis lying close to the head. The proglottides gradually widen until
they reach a breadth of Imm., and in this region are somewhat crumpled (fig. 8).
The last proglottis is shaped like a truncated cone, rather indented at the hinder
narrower end. The hinder edges of the proglottis only slightly overlap the anterior
edge of the following proglottis; they are in all cases but the last wider than the

CESTODA. 4)

anterior border of the same proglottis, and thus each proglottis has, like the last, the
outline of a truncated cone, but it is turned the other way up.

In the centre of each of the middle proglottides is a dark line caused by the
opening of the penis, the oviduct, and the uterus. The penis is most anterior, and is
very muscular, it is in many cases exserted. The base of the penis passes into a
spherical vesicula seminalis. ‘The testes are scattered through the central tissue.

The oviduct crosses the duct of the uterus, which is very short and practically hardly
exists, and ruus backward to the ovary and the shell-gland which lie behind the uterus.

The uterus is but slightly convoluted and contains few ova, they measure
0°042 by 0°035mm.; at any rate, that is about the average, for they vary a good deal
in their dimensions. They have a single and not very thick ege-shell.

Like the cells in D. scotti, the epithelial units of D. wilson’ are remarkably
well defined and show but little differentiation. The parenchyma again is, at any
rate anteriorly, not the vacuolated, spongy-looking tissue which one sees in the
older proglottides, but consists of plump cells, well defined, full of protoplasm, with
nuclei near the edge.

Dibothriocephalus wilsoni—A small form, length 4 to 5°5mm.; greatest breadth
Imm.; nine to thirteen proglottides, like truncated cones; the last is inverted ; no
neck; edges of central proglottides rather crumpled; posterior edges but slightly
overlapping,

It is a remarkable fact that the only Cestoda brought back by the naturalists on
the ‘Discovery’ were obtained from one (and that by no means a common one)
animal, Ommatophoca rossi, or Ross's Seal, an animal, in Captain Barrett-Hamilton’s
words, so little known that it ‘“‘ might, until a year or two ago, have claimed, and
claimed justly,” along with Weddell’s Seal, “ to be considered amongst the rarest and
most obscurely known of all mammals.”* It is also remarkable that the Cestoda
should all belong to the same genus.

If we want to have the history of the Dibothriocephalid species which we find in
this animal, the smallest of the Antarctic seals, we must look to its. food. Ross's Seal
is remarkable for the feebleness and variability of its dentition. “ It seems probable
that the exact number of its teeth is not of importance to this animal.”+ Apparently it
lives on soft food. Wilson mentions, in the work just quoted, that the “food of this
Species consists of octopus and vegetable stuffs or seaweeds,” and again in “ The Voyage
of the ‘ Discovery,” the “jelly-fish and squids, which apparently form their food
Strictly speaking, I do not think that any cestode larva has been found in a jelly-fish,
though Scolex polymorphus is recorded from more than one genus of Ctenophore. On
the whole it seems more likely that the plerocercoid stage will be found—if ever it be
found—in the tissues of one of the Cephalopods.

”

* Report on the Collections of Natural History made in the Antarctic Regions during the voyage of the
‘ Southern Cross,’ London, 1902, p. 2.
t Op. cit., p. 15.

6

ARTHUR E. SHIPLEY.

EXPLANATION OF FIGURES.

Fic. 1.—Transverse section through the head of D. antarcticus, showing the edges of the suckers curling

in round some foreign body, probably mucous tissue of the host.

2.—Transverse section of PD. antarcticus in the region of the neck, showing the regular arrangement
of the longitudinal muscles ; ac., excretory canals ; 7.c., nerve cord.

3.—Dibothriocephalus scotti, X 2.

4.—The head and sucker of D. scoft?, x about 25, two views.

5.—Surface view of D. scotti, x about 25, showing anteriorly the genital opening, g.p. ; the ova, ov.,
scattered in the uterus, and the yolk-glands, y.glds.

6.—Longitudinal section through two proglottides of D. scott’, showing median opening of uterus,
o.ut., penis, /., and opening of vagina, 0.v.

7.—Section through epidermis and external parenchyma of D. scott/.

8.—View of D, wilsoni, X 15.

=e

E. Wilson »Cambridge.

8. D. wilsoni.

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CG na NE RAS

ew n@y ON ARTA
By Sypney J. Hickson, M.A., F.RS.,
Professor of Zoology in the Victoria University of Manchester.
(2 Plates.)

Tue collection of Aleyonaria does not present many very remarkable features. The
most interesting species is Ceratoisis spicata, which forms an important connecting link
between the groups of species formerly separated into the two genera Ceratoisis and
Primnoisis. It is quite unlike any species that has hitherto been discovered.

Primnoella divergens is an important new discovery, as it exhibits many characters
of the genus Caligorgia, and may be regarded as a connecting link between the two
genera.

Clavularia frankliniana and Aleyonium paessleri were found by the ‘Southern
Cross’ expedition off Franklin Island. ~It is a remarkable fact that not a single
specimen of either of these genera was obtained by the Scottish National Antarctic
Expedition.

Thouarella antaretica, which was first obtained off the Falkland Islands, appears
to be a common species in the Southern Seas,

The only species of Pennatulida found was Umbellula carpenteri, a species dis-
covered by the ‘Challenger’ expedition and hitherto found only in the South Polar
seas. Only one specimen was obtained, and this was unfortunately destroyed by fire
in my laboratory.

The ‘Scotia’ expedition obtained twenty specimens of Umbellula durissima, but
not one other specimen of the Pennatulida.

FAMILY CLAVULARIIDA.
CLAVULARIA FRANKLINIANA.
(Plate IL, figs. 20, 21.)
Clavularia frankliniana, Roule, Rep. ‘Southern Cross’ (1902), p. 290.
Localities 1.—W.Q., March 21, 1902, 30 yards from ship on Port Quarter. 8 fms.
a 2.—W.Q., March 21, 1902. 10 fathoms.
Re 3.—W.Q., March 18, 1902. 10 fathoms.
8 4.—W.Q., June 15, 1902. 122 fathoms.
There are many specimens of this species attached to stones, worm tubes and other
foreign objects. I have little doubt they belong to the same species as those described

9
VOL. Ill. A

“a

2 SYDNEY J. HICKSON.

by Professor Roule from 10 fathoms off Franklin Island. At first it seemed
possible that a new specific name should be introduced for these specimens, as
they differ from the description of the type in size, in the character of the stolon,
and in the absence of spicules in the tentacles; but on further examination of
the specimens from locality 4, and some small specimens from other localities
that I had previously overlooked, I came to the conclusion that the species is
very variable and that these specimens cannot be satisfactorily distinguished from
C. frankliniana.

The specimens are found attached to shells, stones, and worm tubes, and the colonies
vary in size according to the nature of their support and the number and character
of the other organisms associated with them. The specimen drawn on Plate IL,
fig. 20, was encrusting a black stone and was not interfered with in any way by
other organisms, but another specimen from the same locality [4], growing on a
worm tube, was associated with Alcyonium paessleri, Polyzoa, Sponges, and other
organisms.

The stolon consists of a number of bands ramifying and anastomosing over the
surface of the support, each about 2-3 mm. in width, but in many places these bands
unite to form a continuous membranous stolon. I have already (2) pointed out that in
C. australiensis both ribboned and membranous stolons occur, and it is quite clear
that this character of the stolon is not one that can as a rule be safely used for specific
distinctions. A study of a number of specimens suggests very forcibly that the
membranous condition is produced by an amalgamation of bands when the circum-
stances of the support permit. The fact that the type specimen is described by
Professor Roule as having ‘stolons membraniformes” is not sufficient evidence to
separate his specimens from these as a distinct species. F

The zooids vary immensely in size. It is true that I have not-found any so large
as the largest of Professor Roule’s specimens, 25 mm. in leneth and 5 mm. in diameter,
but I have measured specimens 20 mm. in length and 3°5 mm. in diameter. They are
scattered at distances of 2-5 mm. on the stolon bands, but are crowded together on the
membranous parts. The body wall of the zooids is opaque, but may have been far
more transparent in the living specimens. It is marked externally by eight well-
defined longitudinal grooves. The tentacles are short and only partially retracted as
in the type specimen. The spicules of the stolon and the basal portion of the zooids
are long spindles with numerous short tubercles. A remarkable feature of many of
these spicules is that one end is often truncated (PI. IL., fig. 21; and see also Professor
Roule’s figures (9), Pl. XLVII., 3a and 3c). They vary in size up to a maximum of
about 0°35 mm. in length. The tentacles of some specimens I examined appeared
to be devoid of spicules, and I cannot determine whether this is due to maceration
in the preservative or to natural conditions. Other specimens, however, exhibit

two rows of short spicules (0°15 mm. in length) on the outer side of the rachis
of the tentacles.

ALCYONARIA. 3)
ALCYONIUM PAESSLERI.
(Plate IL, figs. 22, 28.)
Aleyonium paessleri, May, Hamb. Magel. Samm., Aleyon. (1899), p. 6.

Localities :—1. Off Mt. Erebus, February 8, 1902. 100 fathoms.
2. W.Q., June 5, 1902. D. net hole. 56 fathoms.

3. W.Q., June 15, 1902. D. net hole. 123 fathoms.
4, W.Q., April 1, 1903. No.6 hole. 124 fathoms.
5. W.Q., February 13, 1904. D. net, Hut Point.

In addition to the specimens from the localities mentioned above several small
specimens were found in other bottles. It is evidently a common and widely distributed
species ranging from shallow water to depths of over 100 fathoms.

The largest specimen was from locality 5 (Plate II., fig. 22). The colony is
50 mm. in height and 30 mm. in greatest breadth. It rises from a base of attachment
of irregular form with a maximum width of 15 mm. There are 13 blunt lobes, of
which the largest is 15 mm. X 7 mm. The anthocodiz of this specimen were nearly
all completely retracted.

The spicules of the anthocodiz (of -a specimen from loc. 3) are long spindles
0°35 mm. in length (Plate II., fig. 23b), and the spicules of the ccenenchym of the
same specimen, clubs or short spindles *08-0°1 mm. in length (fig. 23a), as well as a
number of longer spindles of variable size attaining to the same length as those of the
anthocodiz. The two specimens from locality 3 are attached to a black stone, the
specimens from localities 1 and 5 had their bases bent round the very slender stem of
a dead Ceratoisis (Primnoisis). The colour of all the specimens is orange or pale
orange, except the specimen from locality 4, which is white. The smaller specimens
are not branched. The specimen from locality 4 consists of a single lobe 10 mm. in
height by 6 mm. in diameter.

I have compared the specimens with a specimen obtained by the ‘Southern
Cross’ Expedition in 24 fathoms off Franklin Island (3). They cannot, I think,
be separated from the specimens of the species described by Dr. May (8) from
Smyth Sound.

The species of the genus Aleyonium that have been described from Antarctic regions
are A. sollasi, from the Straits of Magellan (‘Challenger’), A. haddon’, Messier Channel
(‘Challenger’) and A. antarcticum, off Heard Island (‘ Challenger’), and’ from Kerguelen
(Studer). It is difficult to give any very precise characters to differentiate these three
species from Alcyonium paessleri, but it is probable that A. antarcticum and A. sollasi
are larger species, the largest specimen of A. paessleri being considerably smaller than
the type specimens of the other two species. Alcyoniwm haddoni may be of the same size
as A. paessleri, but some of the long spindles are ‘7 mm. in length, about twice the
size of any that I found in the specimens at my disposal, and the species is also

WEIN

4 SYDNEY J. HICKSON.

characterised by the presence of a certain number of four-rayed spicules of a type which
does not occur in A. paessleri. On the whole then I am inclined to believe that
A, paessleri is distinct from the other subantarctic species.

FAMILY ISIDA.

In the ‘Challenger’ report on the Aleyonaria, Professors Wright and Studer (14)
proposed a division of this family into three sub-families, Ceratoisidinee, Mopseinee and
Isidinze, based upon the shape of the spicules. The study of many specimens belonging
to the family has convinced me that this sub-division is unnecessary and inconvenient.
The many variations of spicule characters that are found in the species of a single genus
render these structures unsatisfactory for the purpose of wide systematic differentiation.
If we take a single species from each of two of the sub-families and compare them, the
differences observed in the character and arrangement of the spicules may seem to
be of a higher rank than the usual differences between genera; while, on the other
hand, the examination of a large number of species of the same two genera will reveal
so many intermediate conditions as to render the separation of the genera, on spicule
characters alone, impossible. This kind of difficulty is particularly well seen in the
case of the genera Ceratoisis and Primnoisis, which were placed by Professors Wright
and Studer in the sub-families Ceratoisidinee and Mopseine respectively. In both these
genera the branches arise from the calcareous internodes, a character which distinguishes
them from the genera Acanella, Lepidisis and Isis belonging to the same family. The
spicules in both genera are flattened and scale-like, but in the species attributed to
Ceratoisis they are fusiform, whereas in those attributed to Primnoisis they are
irregular flattened scales. In Ceratoisis, moreover, some of the spicules project as thorny
processes from the calyx, whereas in Primnoisis they do not project.

In the description of the Aleyonaria from the Cape of Good Hope (4) I described
a new species under the name Ceratoisis ramosa, which has many characters resembling
some of the species of the genus Primnoisis, but the species appeared to me to differ so
markedly from Primnoisis in having the spicules on the tentacles arranged longitudinally
instead of transversely that I concluded it must belong to the genus Ceratoisis. On
re-examination of the specimens I have confirmed this observation, but may add to
it the fact that many of these tentacular spicules project slightly from the surface.
The examination of the Antarctic specimens brings additional evidence to show the
inconvenience of separating the two genera. The specimen of Ceratoisis antarctica
was found in the same locality as that of Ceratoisis spicata; the former undoubtedly
belongs to the group of species hitherto called by the generic name Primnoisis, as
none of the spicules project from the surface of the calyx; the latter, however, has
very long spicules, many of which project as thorny spines. The projecting spicules
of the calyx of Ceratoisis spicata, moreover, resemble those of C. grandiflora in having
the base bifid (Cf. Plate IL, fig. 18a, with Prof. Studer’s (10) figure Taf. v., fig. 34b),
but whereas those of C. grandiflora seem to be nearly smooth on the surface, those

ALCYONARIA. 5

of C. spicata are covered with little wart-like projections. The spicules of the
ceenenchym of C. spicata are irregular branched plates very much like the scales
of my Ceratoisis ramosa and the Primnoisis group as figured by Professors Wright and
Studer (14), and as they appear in the two species from the Antarctic collection.

The spicules of Ceratoisis spicata are indeed characteristic of the old genus
Ceratoisis in so far as they project as spines from the calyx, but also characteristic of
the genus Primnoisis in so far as their minute structure is concerned. It might be
suggested that Ceratoisis spicata ought to be made a type of a new genus intermediate
between the other two, but the general character of the axis is so similar to that of the
two genera that this course is not to be justified. | have examined carefully the axis of
all the species in the collection and of my species from the Cape, and cannot find any
characters to distinguish them. The internodes in all cases are hollow, marked
externally by shallow longitudinal grooves, but not by spimes or tubercles as in
Acanthoisis. The branches arise from the calcareous internodes, and the first node of
each branch is always some distance from the origin of the branch.

There is never any difficulty in distinguishing the axes of Ceratoisis and Primnoisis
from those of any other genus of the family, but I can find no characters to distinguish
the axis of a Ceratoisis from that of a Primnoisis. When dead specimens with no
calices or ccenenchym are examined, it is possible to identify them as belonging either
to the genus Primnoisis or Ceratoisis, but it is quite impossible to determine to which of
these genera they belong. It is quite possible, for example, that the form recently
described as Primnoisis ramosa by Messrs. Thomson and Ritchie (11) may really he
more closely allied to species hitherto included in the genus Ceratoisis. I would
therefore venture to propose that in future the two genera, Ceratoisis and Primnoisis,
be merged into one, and that the genus Ceratoisis thus enlarged be defined simply as :
“Tsidee, with long, calcareous, hollow internodes, scored with shallow longitudinal
grooves, short horny nodes, branches arising from the calcareous internodes.”

The name Primnoisis should, in my opinion, disappear from our system, but for
convenience sake I have retained the name in brackets in those species here described
which, under the older system, would unquestionably have been placed in the genus
Primnoisis.

CERATOISIS (PRIMNOISIS) DELICATULA.
(Plate IL, figs. 11 and 12.)

Locality :—W.Q., September 8th, 1903. No. 12 hole, 100 yds. 8. of Hut Point.
25-30 fathoms.

The specimens on which this species is founded are in the form of a tangled mass
of delicate branches attached to sponges and worm tubes. ‘There appear to be no main
stems, nor can | find any bases of attachment in the substance of the sponges.
Whether a thick stem was left behind by the dredge or not I cannot say, but the
tenuity and delicacy of the branches are sufficient to justify the specific name I have
given to the species. The diameter of the thickest stems I have measured is 0°65 mm.

6 SYDNEY J. HICKSON.

at the nodes and 0°6 mm. at the internodes. The ramification is irregular and in all
directions, but the branches in all cases arise at an acute angle from the calcareous
internodes. The ccenenchym is very thin, and is absent from a great many of the
branches. The terminal branches are about 0°3 mm. in diameter at the base, and
attenuate distally to a very fine point.

The internodes are 6 mm. long. Here and there shorter internodes occur, but
on the whole the length of the internodes is fairly constant. The calices are quite
irregularly scattered. Usually a group of four or five calices situated at intervals of
1 or 2 mm. stands apart from other groups, but as a great many calices have dropped
off, this grouping may be the result of injury.

The ecalices are bent at an acute angle to the axis; the outside measurement is
about 0°65 mm. The diameter of the calyx at the base is 0°3 mm., and at the crown
0°4mm. The spicules of the coenenchym are flat, tuberculated spindles, varying
from 0°2 mm. to 0°1 mm. in length (fig. 12a). On the neck of the calyx similar
spicules, somewhat bent, are arranged in fourteen or fifteen horizontal rows. The
spicules of the crown and of the backs of the tentacles are often expanded at one end
to form a triangle (fig. 12b).

CERATOISIS (PRIMNOISIS) ANTARCTICA.

(Plate II., figs. 13, 14, 15.)
Tsis antarctica, Studer, MB. Ak. Berlin 1878, p. 662.

Locality :-—(1) McMurdo Bay, February 8, 1902, 96-120 fathoms ; (2) McMurdo
Bay, February 28, 1902, 20 fathoms.

The two specimens which may be attributed to this species are broken from their
base, and each measures about 50 mm. in height. It is probable that they were torn
from the same colony. The branching is quite irregular and shrubby. The internodes
are about 6 mm. in length, but vary a good deal more than in C. delicatula. The
thickest internode in the specimen is about 0°9 mm. in diameter. The calices are
numerous, and situated at intervals of about 2 or 3 mm. on the branches, but gathered
close together in clusters near the extremities. I cannot recognise any spiral arrange-
ment of the calices such as that described for the type by Professors Wright and Studer
(14). Hach full-grown calyx is from 1 to 1°5 mm. in height and stands out almost at
right angles to the axis.

The spicules of the ceenenchym are flat spindles about 0°3 mm. in length (fig. 14a),
and those at the base of the calices are bent. The calices are protected by overlapping
scales of very irregular form and size, but usually straight on one side, convex on the
other, and not exceeding 0°3 mm. in length (fig. 14b). The scales on the back of the
tentacles are all horizontally placed (fig. 15).

The type of this species was obtained by the ‘Gazelle’ in 60 fathoms off
Kerguelen (Studer (10), p. 661), and subsequently specimens were obtained by the
‘Challenger’ in 310 fathoms off Prince Edward Island. I have compared the

ALCYONARIA. 7

specimens in the collection with those obtained by the ‘Challenger, and consider
they belong to the same species, although there are some points of difference between
them. As in C. delicatula, there is no main stem in these specimens, the colony
arising from a tangled mass of branches in a sponge. The main stem may have been
lost, or a colony starting in a sponge may not need, and therefore not form, the stout
supporting main stem; but in either case its absence in these specimens does not
necessarily demand the constitution of a new specific group.

In addition to the specimens referred to above, there are specimens from two other
localities, which probably belong to this species. The localities given on the labels are :
(1) off Erebus and Terror, 500 fathoms, January 22, 1902; (2) E. end of Barrier, 100
fathoms, January 29, 1902. In neither case is any statement made as to the nature of
the preservative used, but as in the first case the spicules are absent, and in the latter
small and apparently corroded, I cannot but suspect that they were treated with picric
acid before being transferred to spirit in the same manner as some of the specimens of
Thouarella antarctica (p. 9) were preserved: The specimens resemble C. antarctica
in the arrangement of the branches, in the size of the calices, and in the size of the
internodes ; but they both differ from the other specimens of C. untarctica in the
collection in having a well-defined main stem. The axis of this stem consists of nodes
about 6 mm. in length, with a diameter of from 1 to L-5 mm. In the specimen from
locality 2 the main stem is 160 mm. long, and the basal part, which is nearly devoid
of ccenenchym, supports colonies of Cephalodiscus hodgsoni.

CERATOISIS SPICATA.
(Plate II, figs. 16, 17, 18.)
Locality :—McMurdo Bay, February 8, 1902. 96 to 120 fathoms.

The base is missing from the specimen, which is about 75 mm. in height. A main axis
may be traced through the whole height, from which secondary branches arise quite
irregularly on all sides. Notwithstanding this, however, by the bending of the secondary
branches the colony becomes almost flabellate. The internodes both of the main axis and
the branches are 12 to 20 mm. in length. At the base the diameter of the internodes
is 1mm. The terminal internodes are not very delicate, being about 0°5 mm. in
diameter where they join the last internode, but they come to a sharp point distally.
The ccenenchym is thin. The calices are irregularly scattered, cylindrical in shape,
about 2 mm. in height when full grown, and situated at distances of 1 to 2 mm. apart
on the lower part of the branches, but clustered at their distal extremities.

The calices are covered with an armature of overlapping scales, some of which are
tri-radiate, others irregular in form (figs. 18b, ¢). Surrounding the crown there are two
or three circlets of spicules, of which one ray projects as a very prominent spine
(fig. 18a). The largest of these tri-radiate spicules are over 0'7 mm. in length, the
spine being as much as 0°45 mm., and the other two rays 0°35 mm. in length. The
other irregular spicules of the calices and the spicules that cover the ccenenchym are of

8 SYDNEY J. HICKSON.

such varying forms that it is difficult to describe them in a few words. Some have
four or five spokes united together at a central hub, some are irregular spindles, others
are forked.
in his Taf. xvii., 19 and 20, of Mopsea in his Taf. xix., fig. 41, are not unlike some of
the spicules seen in my preparations.

The forms of irregular spicules given by Kélliker (7 4) of Paramuricea

The position of this remarkable species is difficult to determine at present. In
the character of its axis it is closely related to Primnoisis, but the spicules are
altogether unlike any species of that genus that has hitherto been described. The
irregular spicules of the coenenchym are like the spicules I described in Ceratoisis ramosa
from the Cape; the spicules of the calyx have a remote resemblance to the forked
spicules of the calyx of Ceratoisis grandiflora described hy Professor Studer, but are
spined and warted instead of bemg smooth.

In the species attributed to the genus Ceratoisis described by Professors Wright
and Studer (14), the internodes vary in length from 15-60 mm. ; in those attributed
to the genus Primnoisis they vary from 2°5-15 mm. (in one species only). The
length of the internodes of C. spicata varying from 13-20 mm. in length brings it,
in this respect, nearer to the Ceratoisis group than to the Prumnoisis group, but
in Ceratoisis ramosa of the Cape the internodes are only 3-5 mm. in length. It
is clear, therefore, that notwithstanding the many resemblances to the Primnoisis
group the species is really more closely related to the Ceratoisis group. In any
case it forms a connecting link between the two groups which renders it very
difficult to regard them any longer as distinct genera.

In considering this question of the amalgamation of the two genera a glance
at the distribution of the species will be of interest.

CERATOISIS GROUP. PRIMNOISIS GROUP.

C. grayi (Wright), N. Atlantic,400 fms.

C. ornata aa Nova Scotia, 250 fms.

C. palme (W. & 8.), Canary Islands,
1125 fms.

C. philippinensis (W. & 8.), Philippines,
82 fms.

P. antarctica (Studer), Kerguelen, 60 fms.

P. antarctica (W. & 8.), Prince Edward
Island, 310 fms.

P. antarctica (Hickson), McMurdo Bay,
20-120 fms.

P. sparsa (W. & §.), Prince Edward

C. nuda (W. & §.), Fiji, reefs.

C. paucispinosa (W. & %&.), Japan,
345 fms.

C. grandiflora (Studer), Fiji, 975 fms.

C. siemensii (Studer), Newfoundland,
1780 fms.

C’. ramosa (Hickson), Cape, 230 fms.

C. spicata (Hickson), McMurdo Bay,
120 fms.

Island, 86 fms.
P. rigida (W. & 8.), Rio de la Plata,

600 fms.

P. capensis (Studer), C. of Good Hope,
50 fms.

P. ambiqgua (W. & §&.), Kerguelen,
10-80 fms.

P. ambigua (Hailes), Lifu, 10 fms.

P. ramosa (Thomson & Ritchie), 74° 8.,
22° W., 161 fms.

P. delicatula (Hickson), W.Q., 25-30 fms.

ALCYONARIA. 9

From this table it will be seen that all the species of the Ceratoisis group, except
C. nuda and C. grandiflora from Fiji and C. ramosa from the Cape, are found
north of the Equator, whereas all the species of the Primnoisis group are found in
the Antarctic seas or south of the Equator. Ceratoisis ramosa is in many respects
an intermediate form, and is perhaps more closely related to the Primnoisis than
the Ceratoisis group; and Ceratoisis spicata is also an intermediate form with closer
affinities to the Ceratoisis group.

FAMILY PRIMNOID/.

This family is represented by two genera, Thouarella and Primnoella, both
belonging to the sub-family Primnoidine.

THOUARELLA ANTARCTICA (12).

Primnoa antarctica, Milne-Edwards, Hist. nat. Corall., i, (1857), p. 140 [Valenciennes Atlas, Voy.
Venus (1846), Zooph., pl. 2, fig. 2].
Thouarella antarctica, Wright and Studer, Chall. Rep. Alcyon. (1889), p. 65 zbique citata.

(Plate IL, figs. 19, 24.)

Localities :—1. W.Q., February 28, 1903. No. 6 Hole. 130 fathoms.
2. Off Coulman Island, January 13, 1902. Dredge. 100 fathoms.
3. McMurdo Bay, February 8, 1902. 96-120 fathoms.
4, Station 270, Mareh 4, 1904. (Just within Antarctic Circle.)
254 fathoms.

The specimens all belong apparently to one species. Only one specimen with
the base broken off was obtained in the first locality (February 28, 1903), and this
I have no hesitation in placing in Valenciennes’ species. ‘The specimens from
off Coulman Island, locality 2, were treated with picric acid before preservation
in alcohol, and this has changed the character of the spicules and thereby the
size of the calices to such an extent that the determination of their species is
rendered uncertain. The specimen from McMurdo Bay is only a fragment, but
it is well preserved, and the calices are identical in general characters with those
of the specimen from locality 1.

All the specimens have the characteristic bottle-brush
branching. Several of them have the main axis quite simple, the twigs, as in the
type specimens, being much more slender than the axis, but the specimen from
locality 1 shows two dichotomous branchings at the base of the axis where the

ce

goupillon””) mode of

eolony is dead and bare, and one specimen from Coulman Island has the axis
bifurcated so that two “ goupillons” spring from the same axis.

The heights of the specimens from Coulman Island are 450 mm. (the specimen
with bifurcated main axis), 175 mm. (a small specimen, but the only one with base
of attachment), 200 mm. and 150mm. The height of the specimen from the

VOL, III. 228

10 SYDNEY J. HICKSON.

Winter Quarters locality is 220 mm. The diameter of the colony is in all specimens
about 30 mm.

The calices are about 1°5 mm. in height. They are clustered together at the
ends, but scattered at considerable intervals near the base of the branches. There
are a few calices on the main axis itself. The spicules are overlapping scales, oval
or heart-shaped on the general ccenenchym and on the base of the calices.
Diameters of these scales, taken at right angles, are about 0°43 mm. x 0°4 mm.
The scales forming the operculum of the calyx have a thick, keeled spine, the
sharp, saw-like keel being on the oval side of the scale and extending from the
tip of the spine to the centre of the plate (fig. 19). The length of the spine is
about 0*4 mm., and the distance from the tip of the spine to the opposite border
of the plate 0°64 mm. The breadth of the plate is 0°43 mm.

The type of this species was found by Captain Thouars off the Falkland Islands.
The species was also obtained by the ‘ Challenger’ near the Crozets in 550 fathoms.
A good account of the genus and of the species belonging to it is given by Dr. Versluys
(13). The species was only figured by Valenciennes (12), but was subsequently
described by Professors Wright and Studer (14) from specimens obtained by the
‘ Challenger.’

I have compared the specimens with an example of Thouarella brucii, kindly lent
to me by Prof. J. A. Thomson, and I am able to confirm the distinction of the species.
The scales are larger in 7. antarctica, and the spines of the coronal scales longer and
sharper than in 7. brucei.

PRIMNOELLA DIVERGENS.
KE. end of Barrier, January 29, 1902. 100 fathoms.
(Plate L, figs. 8, 9 & 10.)

The single-specimen of this extremely interesting species is 135 mm. in height,
but the base of attachment is lost, and the thickest part of the horny axis is
2mm. in diameter. In the first notes I made I placed it in the genus Primnoella,
but on reconsideration and further study I transferred it to the genus Caligorgia, and
gave it the name C. sguamata. Taking advantage of a visit to my laboratory by
Dr. Versluys of Amsterdam, whose great work on the Primnoide of’ the Siboga
expedition (18) has just appeared, I asked him to examine the specimen, with the
result that it is returned to the genus Primnoella with the name P. divergens.
This hesitancy in determining the generic position of the specimen was due to the
fact that it occupies a position in the system almost exactly intermediate between
these two genera. It is either a very divergent Primnoella, or else a very divergent
Caligorgia. It is perhaps a matter of opinion whether it is most nearly related to
the former or to the latter genus. Dr. Versluys pointed out certain characters which
I had overlooked, and converted me to the view that it should be placed in the
genus Primnoella ; but it exhibits so many characters of Caligorgia, which I shall relate

ALCYONARIA. ll

in due course, that there was a great deal of excuse for my original mistake. I wish
to express my thanks to Dr. Versluys for his very valuable advice and assistance in
defining the position of this species.

The genus Primnoella is usually defined as simple or unbranched, but as
Versluys (13) has shown that Narella divaricata of Studer must be transferred to

¢

the genus Primnoella, and this species is “ spirlich verzweigt” (Studer 10, p. 643),
the branching habit of our new species is not quite exceptional.

The branching is irregular and approximately in one plane, so that a large
colony would probably be flabelliform. Some of the branches appear to divide
dichotomously, but in general the smaller secondary branches arise alternately from
the large main branches. The colony as a whole has some general resemblance in
its mode of branching to a species of Culigorgia, figured by Gray (1, p. 37) under the
name Callicella elegans, and to Caligorgia tuberculata, as figured by Versluys (13, pl. vi.,
fig. 15). About one-third of the colony is devoid of ccenenchym and calices.

The number of calices in a whorl varies. On the largest branches there are
eight or nine; on the terminal branches from six to four. On the thicker branches
the whorls are in places scattered, and there are some calices isolated. On the terminal
branches the whorls are about 1 mm. apart.

The calices are 1 mm. in height, and. many of them show a swelling on the axial
side, due to the presence of a gonad. They are protected by three or four rows of five
or six scales, which often overlap when the calyx is dried, but in spirit specimens, and
frequently when dried, appear to be separated by considerable intervals of skin, as
shown in fig. 8. The opercular scales are very small, and the next circle of scales,
called by Versluys the “ Randschuppen,” or marginal scales of the calyx, are not much
larger, but do not overlap the opercular scales. The opercular scales are usually
provided with a short spine, fig. 9, but the marginal scales are rarely, and the other
scales of the calyx never pointed in this way. The opercular scales are about
0°3 x 0°1 mm.,, and the other scales about 0°5 x 0°3 mm. in size; but they vary
a great deal in size, according to their position. —

As in other species of Primnoella the ceenenchym is protected by an armature of
overlapping scales, but these are exceptional in being irregular in arrangement, and
they are not provided with a dentate margin (fig. 10). These scales are usually nearly
square in shape, with rounded edges, and may reach a size of 0°5 mm. across
diagonally. The surface of each scale is ornamented by a series of small tubercles as in
Primnoella. Underneath the scales there are rows of small spicules or ‘
about 0°1 mm. in length, very similar to those drawn by Versluys for Primnoella
australasiz (13, fig. 60, p. 53).

The axis is horny, but contains a considerable amount of calcium carbonate.

The species is related to Primnoella in the following characters. The scales are
thin and covered with small tubercles, but not sculptured nor marked by prominent
lines extending from the nucleus to the margin. The scales of the ccenenchym overlap.

2B 2

‘ sclerites ”

12 SYDNEY J. HICKSON.

The presence of sclerites beneath the scales of the coenenchym, but in this respect it
also resembles Caligorgia ventilabrum. On the other hand, it is related to Caligorgia
in being branched. Caligorgia modesta is only slightly branched, as is also Primnoella
divaricata, but the great majority of the species of Caligorgia are profusely ramified,
whereas the species of Primnoella are, with the one exception mentioned above,
unbranched. It resembles Caligorgia also in having isolated ecalices on the thicker
branches, in the character that the marginal scales do not overlap the opereular scales as
they do in Primnoella, and also in the presence of a distinct but small spine on the oper-
cular and marginal scales. In general characters the scales of the eoenenchym resemble
those of the species of Primnoella, but they do not show the row of teeth on the lower
border, which has suggested to some authors a resemblance to ctenoid scales of fishes.

The geographical distribution of the two genera might be regarded as supporting
the view that our new species is more closely related to Primnoella than Caligorgia.
Species of Primnoella have been found only in the southern seas at depths ranging from
comparatively shallow water to 600 fathoms. Primnoella scotize of Messrs. Thomson
and Ritchie was found as far south as 54° 25’. The latitude of Primnoella divergens is
approximately 76° 8. Caligorgia, on the other hand, occurs in the Mediterranean and
North Atlantic, in the Pacific Ocean and Malay Archipelago, and as far south as New
Zealand, but has not been found off Kerguelen, the Magellan Straits, or in the Antarctic
Ocean.

PHNNATU LACHES
FAMILY UMBELLULIDZ.

UMBELLULA CARPENTERI.
(Plate I., figs. 1-7.)
Umbellula carpenteri, Kolliker, Rep. Chall. Pennatul. (1880), p. 23.

One specimen of this species was obtained off the Barrier on January 27th, 1902,
at approximately 174° E. long. and 178°S. jat., at a depth of 300 fathoms. Mud bottom.

The total length of the specimen is about 700 mm. The stalk is for the greater
part of its length exceedingly slender, 1 to 1°5 mm. in diameter. It begins to dilate
to form the bulb about 135 mm. from the peduncular extremity, and at about 40 mm.
from this extremity the bulb reaches its maximum size, 7 mm. in diameter (fig. 1b).

The autozooids are nine in number. Of these, eight are arranged in the form of
a rosette, the ninth (a) being situated on the distal side (7.e., the side turned away from
the peduncle) of the rosette (fig. 3). This ninth autozooid is probably the primary
zooid (hauptzooid) of the colony. Each of the eight autozooids forming the rosette is
30 mm. in length, the diameter of the rosette being a little over 60 mm. as measured
from the extremity of one autozooid to the extremity of another immediately opposite
to it. These measurements do not include the tentacles, which are about 15 mm. in
length. The ninth autozooid is rather shorter than the others.

ALCYONARIA. 13

The tentacles of the autozooids have some twelve or thirteen pinne on each side
(fig. 7). These pinnz are not always situated opposite to one another nor regularly
alternate. The pinne of one side seem to be developed independently of those on the
opposite side. The size of the pinnz varies in a manner that suggests that new pinnie
are interpolated between the old ones ; but they rarely exceed a total length of 4 mm.

There are numerous siphonozooids. The most conspicuous of these are arranged
in petaloid areas on the under, 7.e., proximal side of the rosette (fig. 2). The apex of
seven of these petaloid area ends at the fork between two autozooids, but the apex of
one area (fig. 2, V,) extends between the two autozooids to reach the distal side, where it
terminates at the base of the ninth autozooid. This area is, according to Dr. Jungersen
(p. 82), the ventral area. At the apex of the dorsal petaloid area, 7.e., the one imme-
diately opposite to this, there is a single siphonozooid distinguished by its greater
size (fig. 2, D.).

The siphonozooids of these areas are about 0°3 mm. in diameter and_ project
slightly as small conical warts or papilla above the coenenchym. There can be no
doubt that they are to a certain extent contracted, as the mouth area is very con-
stricted. From the apex of the cone of many there projects a single long (0°6 mm.)
simple digitiform tentacle (fig. 4). I have little doubt that each siphonozooid has such
a tentacle, but it is broken off or completely retracted in many.

In addition to these, there are many other siphonozooids distributed on the stalk
and bulb. They are very inconspicuous when the surface of the spirit specimen is
examined, but they can be recognised as minute slit-like depressions, arranged in
longitudinal rows, when a simple magnifying glass is used. I cut tangential sections
through a small piece of the upper part of the bulb and found that these siphonozooids
have a diameter of about 0'14 mm. (fig. 6.) The stomodaeum is long, penetrating
right through the thick cortex of the bulb, is oval in section, the longer diameter being
about 0°1 mm., and it has a well marked siphonoglyph (57). The specimen is not
sufficiently well preserved to enable me to state definitely that the dorsal mesenteric
filaments are present, but certain groups of darkly stained cells situated below the
stomodaeum probably represent these structures. These siphonozooids do not possess
a tentacle.

It was at this point in my investigation that a fire broke out in my laboratory
and entirely destroyed the specimen. I am, therefore, unable to give any further
description of the distribution of these siphonozooids. There is no doubt that they
occur all along the thin part of the stalk and on the upper end of the bulb. I believe
they occur also on the lower part of the bulb, but I made no sections to confirm the
external features. It is not possible to make any definite statement concerning the
presence or absence of calcareous spicules in the bulb. There are no calcareous bodies
in the upper part of the bulb, nor are there any in the autozooids or siphonozooids of
the rosette. In the one small piece of the dermis of the lower part of the bulb I could
find none, but it is just possible that a further search might have revealed them.

14 SYDNEY J. HICKSON.

There can be no doubt that this specimen belongs to the same species as those
described by Kolliker (7) under the name Umbellula carpenteri. These specimens were
five in number, and found by the ‘Challenger’ at depths of 1975 fathoms and 1950
fathoms in the south polar seas; the stage of growth of the ‘ Discovery’ specimen
being probably an older one than specimen E of the ‘ Challenger’ series.

But although we may be satisfied to give the specimen Kolliker’s name, the careful
description by Dr. Jungersen (6) of a series of specimens of the north polar and deep
Atlantic species, U. encrinus, has impressed me with the belief that in time these two
species (U. encrinus and U. carpenter’) will be merged into one. There is no doubt that
they are closely related, but as accident has prevented me from further testing this
opinion | must leave the problem for others to consider. The striking similarities in
structure between these north and south polar forms of Umbellula is, however, a matter
of theoretical interest.

LIST OF MEMOIRS QUOTED IN THE TEXT.

1. Gray, J. E. Catalogue of the Lithophytes in the British Museum, (1870).

2. Hickson, 8. J. Trans. Zool. Soc. Lond., XIII., (1894), p. 338.

3. Hickson, 8. J. ‘Southern Cross’ Collections, 1902, p. 293.

4. Hickson, 8. J. Marine Investigations in 8. Africa, the Alcyonaria, Pt. II., (1904), p. 224.
5. Hiles, I. Willey’s Zoological Results, Pt. I1., (1899), p. 196.

6. Jungersen, H. F. E. Pennatulida, Danish Ingolf Expedition, Vol. V., (1904).

7. Kolliker, A. Pennatulida, ‘ Challenger’ Reports, Vol. I., (1880).

7A. Kolliker, A. Icones Histologic, 1864-5.

. May, W. Hamburger Magalhaensische Sammelreise, Alcyonarien, (1899), p. 6.

9. Roule, L. ‘Southern Cross’ Collections, 1902, p. 290.

10. Studer, T. Monatsber. K. Akad. Wiss. Berlin, 1878, p. 662.

11. Thomson, J. A., and Ritchie, J. Trans. Roy. Soc. Edin., XLI., (1906), p. 851.

12. Valenciennes. Voyage sur la Vénus, 1846 (fig. only).

13. Versluys, J. Siboga Expeditie, Mon. XTIIA., (1906).

14. Wright, E. P., and Studer, Th. Alcyonaria, ‘ Challenger’ Reports, Vol. XX XI., (1889).

¢

CO

DESCRIPTION OF THE PLATES.
PLATE I.

Fie. 1.—Umbellula carpenteri (reduced to d size). Au, Crown of Autozooids ; 0., Peduncular bulb.
2.—U. carpenteri. Proximal view of crown of autozooids. Natural size. Si., Petaloid area of
siphonozooids ; D., Dorsal petaloid area terminating in a large siphonozooid; V., Ventral
petaloid area ; G., An autozooid that was injured, the tentacles missing.
» 3—U. carpenteri. Distal view of the crown of autozooids. a, the ninth or “ Haupt” zooid.
» 4.—U. carpenteri. Four siphonozooids of the petaloid areas. ent., the single long tentacle of each
siphonozooid, x 40 diams.
» 5.—U. carpenteri. Transverse section of one of the siphonozooids of a petaloid area, x 120. Si.,
Siphonoglyph ; d. m., Dorsal mesenteries.
» 6.—U. carpenteri. Transverse section of a small siphonozooid of the peduncular bulb, x 120.
» 7.—U.carpenteri. One of the tentacles of an autozooid, to show the arrangement of the pinn, x 23.
» &.—Primnoella divergens. Two whorls as seen in a spirit specimen, showing the manner in which
the scales project on the surface, x 10.
5 9.—Primnoella divergens. A spicule of the calyx, x 50.
» 10.—Primnoella divergens. A spicule of the coenenchym, x 50.

a

ALCYONARIA, is)

PLATE II.

Fie. 11.—-Ceratoisis delicatula. A few branches of a colony, x 2.

12 —Ceratoisis delicatula. a, Spindle-shaped spicule ; 4, triangular plate, x 100.

_13.—Ceratoisis antarctica. A terminal branch, x 12.

14.—Ceratoisis antarctica. a, Spindle-shaped spicule ; 0, plate, x 100.

15.—Ceratoisis antarctica. View of corona and folded tentacles, to show the arrangement of the
spicules, x ca. 50.

16.—Ceratoisis spicata. A branch, x 2. At. the horny nodes may be seen.

17.—Ceratoisis spicata. Side view of a calyx, x ca. 30.

18.—Ceratoisis spicata. Spicules. a, Forked spicule of a calyx; 6 and ¢, irregular spicules of the
ccenenchym and calyx base, x 50.

19.—Thouarella antarctica. A spicule of the corona, x 60. (See also Fie. 24.)

20.—Clavularia frankliniana, Nat. size.

21.—Clavularia frankliniana. Spicule of body wall, x 75.

22.—Aleyonium paessleri. Nat. size.

23.—Aleyonium paessleri, a, Short club spicule of the coenenchym, x 150; 0, long spindle-shaped
spicule of the body wall of an anthocodia, x 100.

24.—Thouarella antarctica. A small piece of a branch of a dried specimen, drawn from a photograph,
X ca. 20.

ra

E. Wilson, Cambridge

Alcyonaria pl. lI.

Antarctic (Discovery) Exp.

CAP AA

E. Wilson, Cambridge.

Alcyonaria pl. Il.

Antarctic (Discovery) Exp.

1

fe Ep rol: ZQOOPMYVTES:

By Sypney J. Hickson, M.A., F.R.S., Professor of Zoology in the Victoria
University of Manchester ; and
F. H. Gravety, BSc., Research Scholar in the Victoria University of Manchester.

(4 plates.)

THE collection of Hydroid zoophytes made by the ‘ Discovery’ Expedition proved
to be remarkably rich and interesting. At the first inspection there seemed to be
but few species, and these (with the exception of a few solitary forms of Lampra)
were large, ramified and gorgonia-like in consistency ; but a careful examination of
these large colonies soon revealed other species of epizoic habits which rapidly
increased in numbers as our investigations proceeded. In the end the number of
distinct species was twenty-five, or about twice as many as we expected to find.

The large colonies of Haleciwm arboreum support Perigonimus antarcticus,
Stylactis halecti, Campanularia everta, C. laevis, Campanulina, and Halecium
tenellum.

Perigonimus antareticus supports Campanulina A., Eudendrium insigne, and
Lafoéina longitheca. Eudendrium insigne was also found on a specimen of the
Aleyonarian genus Ceratoisis, Sertularella plectilis and Campanulina B. are
attached to a colony of Campanularia verticillata.

Of the twenty-five species only two—Obelia geniculata from the Auckland
Islands, and Dictyocladium fuscum from Coulman Island—were found outside the
limits of McMurdo Bay and the edge of the great ice barrier. In other words,
twenty-three of the twenty-five species represent the hydroid zoophyte fauna of
the most southerly limit of our knowledge of marine zoology. Two species—
Lampra microrhiza and Plumularia glacialis—were found only at the east end of
the barrier.

It seems probable that the part of McMurdo Bay from which these specimens
came is covered with a continuous sheet of ice for the greater part of each year
and in some years has no open water. There is good reason for believing that
the great ice barrier is afloat, and consequently the few specimens obtained by the
Expedition at the east end of the barrier may represent samples of a fauna that
extends for some distance under the barrier towards the South Pole.

We may regard this collection of Hydroid zoophytes as the representatives of
a sub-glacial fauna, and subject to the condition that larve or free swimming

VOL. III, 2 C

2 SYDNEY J. HICKSON ann F. H. GRAVELY.

gonophores, if they occurred, could never or very rarely reach the surface of the
sea. It is, therefore, noteworthy in this connexion that, although there are eight
families represented, not a single species exhibits free swimming medusiform
gonophores. The only species in the whole collection with free swimming medusze
is Obelia geniculata from the Auckland Islands.

The question whether a particular specimen of zoophyte is or is not the type
of a new species must be, to a certain extent, a matter of opinion, or perhaps of
prejudice, of the systematic zoologist who describes the collection. The actual number
of new species in this collection therefore is not a matter of great statistical
importance. We regard, however, ten of the twenty-three sub-glacial species as
certainly new to science, and five species as probably new. Four species have only
been found elsewhere in Southern seas, one on the coast of California, and three are
European. Of the three European species only one— Halecium tenellum — has
hitherto been found in Southern seas.

The noteworthy features of the collection as a whole are: the large proportion
of new species, the absence of any definite new generic type, and the occurrence of
three species (excluding Obelia geniculata, which is well known to occur in Southern
seas) that are common species on the British coast.

The most remarkable and interesting species is undoubtedly Hydractinia dendritica,
a new species, which we have decided to study in greater detail. The question of the
extent of degeneration of the gonophores of the sub-glacial species as compared with
that of similar species living in open seas, is one that appears to us likely to furnish
some interesting results if carefully pursued.

In conclusion we wish to express our sense of admiration and appreciation of the
services rendered to science by Mr. Hodgson, the biologist of the Expedition, in
collecting these Hydrozoa, The work of boring holes in the ice and of patiently
dredging under the severe conditions of an Antarctic winter must have been of a
nature that demanded extraordinary skill and enthusiasm in the cause of zoology.

The following is a complete list of the species we have described. They all come
from McMurdo Bay, except those with specially named localities.

There is not sufficient material to make any definite statement as to bathymetric
range, but it is noteworthy that several species were found in depths ranging from
shallow water down to 130 fathoms.

GYMNOBLASTEA.
FAM. BOUGAINVILLIIDAE.

Perigonimus antarcticus, sp. n. 10-130 fathoms.
Budendrium insigne, Hincks. 10-20 fathoms.
Stylactis halecti, sp. n. 20 fathoms.
FAM. PODOCORYNIDAE.

Hydractinia dendritica, sp. n. 5-10 fathoms.

HYDROID ZOOPHYTES.

oo

FAM. TUBULARIIDAE.
Tubularia ralphii, Bale. 10-20 fathoms.
Tubularia hodgsoni, sp. n. 130 fathoms.
Tubularia longstaffii, sp. n. 124 fathoms.
FAM. CORYNIDAE.
Two undetermined species. 0-20 and 100 fathoms.

FAM. CORYMORPHIDAE.

Lampra parvula, sp. n. 10-20 fathoms.
Lampra microrhiza, sp.n. HH. end of Barrier. 300 fathoms.

FAM. MYRIOTHELIDAE.
Myriothela (?).

CALYPTOBLASTEA.

FAM. SERTULARIIDAE.

Sertularella spiralis, sp. n. 130 fathoms.
Sertularella plectilis, sp. n. 0-130 fathoms.
Dietyocladium fuscum, sp. n. Coulman Island. 8-15 fathoms.

FAM. PLUMULARIIDAE.
Plumularia glacialis, sp. n. EK. end of Barrier. 100 fathoms.

FAM. CAMPANULARIIDAE.
Sus-Fam. CAMPANULARIINAE.
Campanularia verticillata, Linneus. New variety. 10-20 fathoms.
Campanularia everta, Clark. 0-20 fathoms.
Campanularia laevis, Hartlaub. 0-20 fathoms.
Susp-Fam. HALEcIINAE.
Halecium arboreum, Allman. E. end of Barrier and McMurdo Bay. 0-130 fathoms.
Halecium tenellum, Hincks. 10-20 fathoms.
Sus-Fam. LAFOEINAR.
Lafoéina longitheca, Jiderholm. 0-20 fathoms.

FAM. EUCOPIDAE.
Obelia geniculata, Linneeus. Auckland Islands.
Campanulina (A). 0-20 fathoms.
Campanulina (B). 0-20 fathoms.

THE CLASSIFICATION ADOPTED.

One of the greatest difficulties that the systematic zoologist has to meet in writing
an account of a collection of Hydrozoa is the determination of the system of classifica-
tion that he will adopt. There are so many different opinions as to the relative
systematic value of the characters presented by the hydrosome and gonosome
respectively, and our knowledge of the extent of the modification of these characters
by environmental conditions is so imperfect that every system of classification that

PATOL YZ

4 SYDNEY J. HICKSON anp F. H. GRAVELY.

has been proposed must present to those who are working upon new materials or on
new lines of research many inconsistencies and inconveniences.

The best classification is, after all, the one that is most convenient for the
particular class of investigation that the author is engaged upon, and consequently
those who approach the Hydrozoa from one side will be inclined to adopt a classifica-
tion which to authors who approach it from another seems erroneous or unsatisfactory.

It is clearly not to the advantage of Science that the classification of a group of
animals should constantly change, and it is better to adopt one which may in some
respects seem unsatisfactory than to propose alterations upon any grounds other than
those of wide and far-reaching new investigation.

Allman and Hincks, the two great pioneers of the zoology of Hydrozoa, distributed
the genera amongst a large number of families; in fact, according to their system a
great many genera stand alone, or almost alone, in a family.

The tendency of recent systematists has been to rearrange the genera in such a
manner as to reduce the number of families, and this tendency appears to us to be not
only more convenient but to be founded on a sound scientific basis.

The system we have used is that adopted by one of us in his essay on the
Coelenterata in the Cambridge Natural History, Vol. I.; a system which, like any other,
is open to many criticisms in detail, but has been found on the whole to suit our
purpose as well as any other.

FAMILY BOUGAINVILLIUDAE.

This family includes, according to our system, the sub-families Bougainvilliinae
(Bougainvilliidae, Gegenbaur), Margelinae (Margelidae, Heeckel), Dicorynae (Dicory-
nidae, Allman), Eudendriinae (Eudendriidae, Hincks), and the Bimeriinae (Bimeriidae,
Allman).

The hydranths in this family have a single circle of filiform tentacles, and the base
of the hydranths is protected by a tube of perisare.

The inclusion of Stylactis in the sub-family Bimeriinae is perhaps the most
unsatisfactory feature in this arrangement, but as we have found im some cases a short
collar-hke tube of perisare at the base of the hydranths (fig. 33, ¢. p.), which has not
been observed, so far, in any species of the family—the Podocorynidae—to which in
other respects Sty/actis has many aftinities, we have retained it in this family.

SUB-FAMILY BOUGAINVILLIINAE.
PERIGONIMUS ANTARCTICUS.
(Plate I., figs. 1, 2, 3; and Plate IV., fig. 32.)
Perigonimus sp., Hartlaub, Voy. du Belgica, Hydroiden, (1904).
Locality.—Common in McMurdo Bay at depths of 0-130 fms.
The species was found in no less than eleven of the bottles sent to us, and is usually

HYDROID ZOOPHY'TES. 5

attached to the stems of //alecium arboreum. The character of the bottom on which
its support grows is described as stony, gravelly, or very rough ground (Flagon Pt.).

The species differs from most of the species of Perigonimus in having lfixed
gonophores.

On this account it might be placed by some authorities in Allman’s genus
Wrightia, but for reasons that have recently been urged by Motz-Kossowska
(17: pp- 68-71) we are of opinion that Wrightia should be merged with Perigonimus.
In this particular case the reasons for disregarding the genus Wrightia seem to be
particularly strong. The size of the colonies and of the individual zooids being much
greater than in the only known species of Wrightia, the specimens would, in the
absence of the gonophores, be undoubtedly referred to the genus Perigonimus. If
Perigonimus shares the power or possibility that some other genera of gymnoblastic
hydroids undoubtedly possess of variation in the character of the liberation of the
gonophores, being in some cases phanerocodonic and in others adelocodonic, we should
at least expect that the adelocodonic variation or condition would occur in specimens
living in an arm of the sea such as McMurdo Bay, that is for so many months in the
year covered with ice.

Hydrosome.—¥rom the ramifying hydrorhiza attached to the Halecium several
unbranched or occasionally slightly branched hydrocauli arise (fig. 1). They attain to
a height of about 8 mm. Many of the hydrocauli appear to be simply unattached
branches of the hydrorhiza, and even the pedicels of the gonophores occasionally give
off branches of indefinite function and power of growth.

The transition from hydrocaulus to hydranth is gradual, the length of each
hydranth being about 1 mm. The hypostome is conical and is surrounded at its base
by a circlet of about 10 filiform tentacles*each about 0°6 mm. in length. The
perisare is continued as an exceedingly thin film over the hydranth as far as the base
of the tentacles. The hydranths vary considerably in shape (fig. 3) and are probably
very contractile.

Gonosome.—The gonophores are situated on short pedicels which, in the case of
the female, are thickened distally. The colonies appear to be invariably dioecious.
In both sexes the gonophore is a degenerate medusa. In both sexes the gonophore
is protected by a thin layer of perisarc. It is larger in the female than in the male
(1:1 mm. x 0°9 mm. in the female, and 0°9 mm. x 0°7 mm. in the male).

In the female gonophore there is a large sub-umbrella cavity (fig. 3, sw.c.), the
manubrium is well developed and has a well-marked endoderm cavity.

In the young gonophore there is a distinct endodermal layer of cells and
mesogloea in the umbrella, but in the adult gonophore (fig. 32) these are reduced
to a non-cellular mesogloea except at the margin, where a cord of cells represents
the ring canal. There are no radial canals in the adult gonophore.

In the male gonophore the sub-umbrella cavity is completely filled with sperm
cells (figs. 2 and 32, sp.).

SYDNEY J. HICKSON anp F. H. GRAVELY.

lor)

It is possible that this species of Perigonimus is identical with the one obtained
by the ‘Belgica’ in 71° 15' S. and 87° 39’ W. (8: pp. 8-9; Pl. L, fig. 2); but
Dr. Hartlaub had not the good fortune to be able to examine and report upon the
gonophores.

The hydrosome has also some resemblance to that of the British species
P. coccineus (Wright, see Hincks, 11: pp. 97-98) of which the gonophores are not
known.

Of the better known British species it has some affinities with P. serpens
(Allman, 2: pp. 327-328; Pl. XI, figs. 7-9), but differs from it in the more slender
hydrocauli and the more distinct difference between hydrocaulus and hydranth and
in the adelocodonic gonophores.

Sars (21: pp. 28-32; Pl. IL, figs. 37-43) has described a species from
20-30 fathoms off Manger, Norway, which he named Rhizoragium roseum. This
species appears to us to be so closely related to Perigonimus antareticus that it
might with some propriety be placed in the same species. The reason for separating
Rhizoragium roseum from the genus Perigonimus was undoubtedly the adelocodonic
medusoid character of the gonophores, but in the character of the hydrosome it is
undoubtedly a Perigonimus.

Sars describes the ‘“ medusa-buds” as uncommonly large (up to 1 mm. in diam.)
in proportion to the hydranths, the claviform naked part of which is only 0°3 —
0°5 mm. in diameter. They are not attached to the naked part, but are situated
on the creeping hydrorhiza as in P. muscoides. The degeneration of the gonophores
consists in a reduction of the umbrella-wall and the loss of the radial canals and
umbrella-mouth. In the oldest gonophores, however, the margin of the umbrella
was thickened, and judging from the figure, it bore rudimentary tentacular processes.

P. antarcticus resembles Rhizoragium roseum in many of these characters and
also in the shapes and general characters of the hydranths and the number of their
tentacles, but differs from it in the slightly branching habit of the hydrocauli and
in having some of the gonophores arising near the proximal ends of the hydrocauli
instead of only from the hydrorhiza. The gonophores of P. antarcticus are protected
by a chitinous perisarc, but this is very thin, and may have been overlooked by Sars
in his species. We have not found in our species any processes on the gonophores
corresponding with the tentacular processes figured by Sars. However, in Rhizoragium
the tentacular processes only occur in gonophores old enough to contain planulae
larvae. In our species, on the other hand, the more mature gonophores exhibit a
less well developed marginal thickening and in other respects the umbrella-wall is
more degenerate than in the younger stages, and it therefore seems to us improbable
that the tentacular processes would be present in stages old enough to contain larvae.

Our conclusion is, therefore, that it is more convenient to regard Rhizoragium
rosewum—which should in our opinion be called Perigonimus roseus—and Perigonimus
antarcticus as distinct species,

“N

HYDROID ZOOPHYTES.

SUB-FAMILY EUDENDRIINAE.
EUDENDRIUM INSIGNE.
(Plate L., fig. 4.)
Eudendrium insigne, Hincks, British Hydroid Zoophytes (1868), pp. 86-87.

Localities —McMurdo Bay, February 20th and 28th, 1902; March 21st, 1903;
10-20 fathoms.

This delicate little hydroid, consisting of small irregularly branched colonies, was
found attached to other Coelenterata, such as Ceratoisis and Campanularia. t did not
occur in great abundance, but a few colonies were found in several bottles of specimens
obtained in McMurdo Bay.

IHydrosome——The hydrorhiza consists of a plexus of branching roots loosely
attached to its support. At frequent intervals it gives off hydrocauli, which

are themselves branched. These stems are very slender, strictly monosiphonie,
seldom upright, but ‘growing in a straggling tangle like the stems of a climbing
plant searching for a new support. The hydrorhiza and the free hydrocauli are
invested by a thin straw-coloured perisare, which is slightly annulated at the base of
and at intervals on the hydrocauli.

There is considerable difficulty in distinguishing between hydrorhiza and the
stem, and many of the stems that are now free may possibly have been at one time
attached to the support. This difficulty renders the estimation of the height of the
colony a matter of conjecture, but it is about 25 mm.

The perisare frequently ends very abruptly at the base of the hydranths,
but m some cases it seems to attenuate gradually.

The hydranths are 0°5 mm. in height and have the usual characters of the
genus. There are about twenty filiform tentacles 0°5 mm. in length, arranged in
a single verticel at the base of a trumpet-shaped hypostome (fig. 4).

At the base of the hydranth there is a circular groove bounded proximally
by a collar of very conspicuous deeply-staining cells (fig. 4, ¢.). Occasionally
both collar and groove are apparently absent.

Hincks does not give a clear figure of this groove or collar in the British
specimens, but states (p. 87) that ‘there is a circular groove near the base of the
body, from which the gonophores spring—a portion of the structure which I
misinterpreted at first, and which led me to suppose that there was a shallow
cup round the base of the polypite.” From this quotation it would appear that in
Hincks’ specimens, as in the Antarctic forms, the lower margin of the groove was
sometimes slightly swollen out to form a collar. In general form and size the
Antarctic specimens resemble the European specimens, but they differ from them
in the respect that the perisare is less “closely ringed throughout.”

8 SYDNEY J. HICKSON ann F. H. GRAVELY.

Although Eudendrium insigne appears to he widely distributed in the seas of the
Northern hemisphere, it is not included in Hartlaub’s list (10: pp. 505-509) of

Southern species.

SUB-FAMILY BIMERIINAE.
FENUS STYLACTIS.

The generic name Stylactis was introduced by Allman for two species referred
to the genus Podocoryne by Sars (P. fucicolu, and a variety of P. carnea). The
principal characters that distinguish the genus from Podocoryne are—(1) The
absence of any superficial coenosare covering the hydrorhizal plexus; and (2) the
gonophores in the form of sporosacs instead of free swimming medusa. From
Hydractinia the genus is distinguished by the first of these characters, but it agrees
with it in the second character.

Allman placed the genus in his family Bimeriidae, and thus removed it from the
neighbourhood of the other two genera.

The opinion of later writers appears to favour the view that Stylactis is more
closely related to /Hydractinia and Podocoryne than Allman’s classification suggests.

Bonnevie (5: p. 485) unites Hydractinia and Podocoryne imto one genus,
Hydractinia, and Motz-Kossowska (17: pp. 81-85) imeludes in the same genus the
two species that formed the genus Stylactis of Allman, and has added a new species
HT. pruvoti from the Balearic Islands, which is intermediate in characters between the
species attributed by older authors to the genera Stylactis and Podocoryne
respectively.

We are quite convinced of the general affinities of the three genera, which
are indeed emphasised by this collection from the Antarctic Sea in so far as we
have a species of Stylactis with dactylozooids of a simple kind, and a species of
Hydractinia without dactylozooids, the usual condition beg that Stylactis has
dactylozooids and //ydractinia has not. At the same time, the hydrorhiza of our
two forms is so distinct and the minute characters of the gonophores so different
that we have thought it better to retain the generic name Stylactis and keep it in
the family Bougainvilliidae for the present.

STYLACTIS HALECTII.
(Plate I., figs. 5, 6 ; and Plate IV., fig. 33).

Locality :—McMurdo Bay; February 28th, 1902. Found at depths of less
than 20 fathoms.

A considerable quantity of this interesting species was found encrusting the
thicker stems of Haleciwm arboreum. It arrived in a fairly good state of preservation
notwithstanding that the bottle containing it was broken in transit.

Hydrosome.—The hydranths arise directly from an encrusting hydrorhiza

HYDROID ZOOPHYTES. 9

consisting of a dense mass of branching and anastomosing tubes (fig. 6). Each
tube is covered with its own very thin sheath of perisarc (fig. 33) and there is no
common sheath of coenosarc covermg the hydrorhiza as a whole, such as we find
in the Podocorynidae. In the central parts of the hydrorhiza the tubes are closely
packed, anastomose freely, and are disposed in several layers. At the periphery
however the tubes are reduced to a single layer, become more dispersed, and
anastomose slightly (fig. 3). There are three kinds of zooids.

In the central part of the colony there are gastrozooids and blastostyles (gonozovids)
(fig. 6); at the periphery, gastrozooids and dactylozooids (fig. 5). The gastrozooids
(figs, 5 and 6, gz.) are 1-2 mm. in height. They exhibit a conical hypostome
surrounded by a circlet of six to ten simple tentacles each about 0°5 mm. in leneth.

The dactylozooids (fig. 5, d.) are short finger-like structures 0°25 mm. long by
0°06 in diameter, terminating in a pad distally which bears a battery of nematocysts.
The dactylozooids appear to be covered with a chitinous perisarc, but in sections
it is seen to be extremely thin or absent at the distal extremity. We have some
specimens with the nematocysts discharged, and there can be little doubt therefore
that the battery is functional. These dactylozooids have no tentacles. The
blastostyles are shorter than the gastrozooids, and usually exhibit neither mouth
nor tentacles (fig. 6, b/.). There is always a short conical hypostome armed with
nematocysts, and occasionally this is surrounded by a circle of four rudimentary
tentacles (fig. 6, b/. t.).

The body of the blastostyle is usually considerably dilated and has a
superficial resemblance to a simple ovoid sporosac.

Gonosome.—The medusoid structure of the gonosome is completely reduced
in the male, but as no female blastostyles were found we can make no statement
to the effect that the same is true of both sexes. The sperm cells (fig. 33, sp.) are
found in a dense cluster between the ectoderm and endoderm even in the youngest
blastostyles we have examined (0°1 mm. in length), and neither in these nor in the
older blastostyles can we find any true medusoid structures.

FAMILY PODOCORYNIDAE.

In this family we include Podocoryne (Sars), Hydractinia (Allman), and other
less well-known allied genera. The very interesting new genus //ydrodendrium
(Nutting) may, we consider, be now included in this family, as the species //ydractinia
dendritica connects it with the other species of //ydractinia.

HypRACTINIA DENDRITICA.
(Plate Il., figs: 7, 8, 9, 9a, 10.)
Localities.—Specimen A: W.Q., March 21st, 1902; —10 fms. Specimen B:
Locality unrecorded. Label lost.

you. It. 2D

10 SYDNEY J. HICKSON anp F. H. GRAVELY.

It- is necessary in the description of this very remarkable hydroid to refer
constantly to the special characters of the two specimens we received. We shall
therefore call them specimen A and specimen B respectively.

Specimen A consists of a single continuous colony encrusting the stems of a
specimen of falecium arboreum. From this encrusting mass, which possesses all the
general features of an ordinary //ydractinia, a single upright branching stem arises,
which has some resemblance to the stems of Hydrodendrium gorgonoides (Nutting 20:
pp. 936-938; Pl. I, figs. 1-6; Pl. VII. figs. 1-2).

Specimen B consists of a large number of brittle and broken stems bearing
Hydractinian hydranths, but without any encrusting base or hydrorhiza. It seems
probable that all these broken stems belong to one colony, and we are convinced
that specimen B belongs to the same species as specimen A.

Specimen A—There are. two regions in this specimen, the encrusting or basal
region, and the upright branching stem, the rhizocaulus. The basal part (fig. 9,
enc. ”., fig. 9a) entirely surrounds the polysiphonie stems of Halecium arboreum, only
a few pinnules of the supporting hydroid penetrating it and being exposed. It is
about 0°4 mm. thick, the outer part to a depth of about 0°2 mm. from the surface
containing coenosare, the lower part consisting of a lacunar skeleton with strands of
tissue in some of the lacunze, whilst others may be empty. The “spines” of other
species of Hydractinia and of Podocoryne are represented in this species by a series
of low ridges (fig. 7, 7. sp.), often continuous with each other, but projecting
irregularly on the surface of the colony. They have some resemblance to the
hydrophores of Ceratella (Spencer 21), but seem to have no definite relation to the
zooids. There are only two kinds of zooids, the gastrozooids and the blastostyles
(gonozooids).

The gastrozooids (fig. 7, gz.) vary a good deal in length. The usual length is
about 2 mm., but they are in some cases as_much as 4 mm. in length. There is a
conical hypostome surrounded by a single circlet of from 9 to 13 tentacles, each
about 0°6 mm. in length. It is evident that the gastrozooids are extremely
contractile, and it is noteworthy that in some cases they have been killed introverted,
the circlet of tentacles having assumed a position at the base.

The blastostyles (fig. 7, b/.) are from 0°3-0°7 mm. in height. They are small
and degenerate. They usually exhibit a few small tentacles 0°05 mm. in length, but
in some cases no tentacles at all could be seen. They may have a minute mouth,
but usually have not. The gonophores (fig. 7, gph.) are all probably female and
in the form of sporosacs. They occur in a single circlet round the base of the
blastostyle.

The upright branching stem of this specimen rises to a height of about 40 mm.,
and is about 0°8 mm. in diameter at the base (fig. 9, fr. rhc.). The ramification is
irregular, the eight or nine terminal branches ending in some cases in a long
filamentous process. The surface of these branches is remarkably smooth. The

HYDROID ZOOPHYTES. 1]

gastrozooids and blastostyles at the base of the stem are very similar to those of the
basal encrusting part of the colony, but distally the gastrozooids are smaller and
apparently less contractile, and blastostyles are absent.

Specimen B.—Assuming that the pieces in the bottle containing this specimen
all belong to one colony, we have estimated that the height of the colony must have
been at least 150 mm. There is no encrusting basal support as in specimen A, and
the axes of the branches do not show any foreign hydroid or other kind of core. The
branches arise irregularly and anastomose freely (fig. 10). They are circular in section,
remarkably smooth on the surface, and their maximum diameter is about 3 mm.
They are therefore much longer and thicker than the upright branching stem of
specimen A, and we may add presumably older. Although there is no true basal part
similar to that of specimen A, the encrusting habit is seen in places where sponge
spicules and other foreign bodies have been overgrown by the colony.

The skeleton is composed of a series of parallel intercommunicating chitinous
tubes, the superficial tubes being externally incomplete, but there are no definite
ridges or spines on the surface as in the basal part of specimen A.

On the larger branches there appear to be no zooids at all. At the distal ends
there are numerous small immature zooids which may become either gastrozooids or
blastostyles, as well as a considerable nymber of gastrozooids. These gastrozooids
(fig. 8, gz.) are about 1°5 mm. in height, and therefore slightly smaller than the
majority of the gastrozooids of the basal part of specimen A. The mouth is on a
conical hypostome which is surrounded by a series of filiform tentacles, 6-10 in number,
and each one about 0°6 mm. in length. Proximally to the region where the immature
zooids and gastrozooids occur there is a region with numerous ripe blastostyles
(fig. 8, bl.), and only a few gastrozooids. These blastostyles vary from 0°3 to 0°7 mm.
in height, but the majority are larger than those of A. They have 4-8 tentacles 0° 1-
0°2 mm. in length, and have in some cases a minute mouth. The blastostyles each
bear from 1—5 sporosacs (fig. 7, gph.) which in our specimens were all male, and when
ripe about 0°3 mm. in diameter. The sporosacs are borne just above the base of the
blastostyle. The branch shown in fig. 7 is somewhat intermediate in character between
the region of gastrozooids alone and the typical region of blastostyles.

In comparing the two specimens we notice certain differences between the basal
part of specimen A and specimen B which might be regarded by some authors to be
of sufficient importance to necessitate their separation into distinct species. Thus, the
surface of B is smooth, of the basal part of A ridged ; the gastrozooids are smaller in
B than in A; the blastostyles of, B are on an average larger than in A, and have a
larger number of longer tentacles; the sporosacs of B are larger and less numerous
than those of A, and are situated above the base, and not at the base, as in A. More-
over in B the skeleton has the form of a series of parallel but communicating tubes,
whereas in A it has the same irregular lacunar arrangement that is found in //. echinata

and other species.
2D 2

12 SYDNEY J. HICKSON ann F. H. GRAVELY.

The fortunate preservation of a small and probably young branching stem of
specimen A, with gastrozooids at its proximal end similar to those of the basal parts
and at its distal end similar to those of specimen B ; with a smooth surface similar to
that of specimen B, and ramifying and growing without any axial support as
specimen B does, may be regarded as conclusive evidence that the specimens belong to
the same species.

The species resembles //ydractinia in having sessile hydranths, a thick membranous
hydrorhiza covered with a continuous sheath of ectoderm and provided with a lacunar
chitinous skeleton, and in having adelocodonic gonophores.

On the other hand, it differs from many of the species of //ydractinia in
forming large unsupported rhizocauline branching stems, and in the absence of
dactylozooids.

A species that has close aftinities with H. dendritica is H. angusta, from 71° 8. and
87° W. 400 metres (Hartlaub 9: pp. 7-8; Pl. IV., figs. 1-6). It forms branching (?)
cylindrical rhizocauline stems. It has also tentaculate blastostyles and no dactylo-
zooids. But it has thorny processes on the surface, which in our species are confined
to the basal part; the gastrozooids of our species are quite twice as large and the
tentacles are more numerous than in //ydractinia angusta.

It differs from /Zydrodendrium gorgonoides (Nutting 20: pp. 936-938; Pl. I.,
figs. 1-6; Pl. VIL, figs. 1-2) from Hawaii, in having definite blastostyles, in the
presence of a large hypostome on the gastrozooid, in the colonies being unisexual,
and in other characters. It resembles Hydrodendrium in the occurrence of branching
brittle rhizocauline stems, in the absence of spines on the surface, and in the
absence of dactylozooids.

Hydractinia angusta and Hydractinia dendritica form two interesting links in a
chain connecting the ordinary species of Hydractinia with Hydrodendrium. It may be
noted here that im addition to the species of //ydractinia mentioned above that have no
dactylozooids, Hydvaetinia parvispina {Hartlaub), 7. earnea, var. inermis, I, humilis,
and //. provuti (Koss.) are said to have no dactylozooids ; and in other species described
by Bonnevie (6), Hincks (11), and Allman (2) no mention is made of these peculiar
zooids. The presence of dactylozooids cannot therefore be regarded as a character of
the genus.

FAMILY TUBULARIIDAE.
GENUS TUBULARIA (Linn. emend. Allman).

We have found in the collection what appear to be three distinct species
of Tubularia, but of these, one is represented by a single hydranth, and one
by two hydranths. The third species agrees fairly well with the description given
in Bale’s Australian Zoophytes of a species described’ in MS. by Halley from
Hobson’s Bay.

HYDROID ZOOPHYTES. 13

TUBULARIA RALPHI.

(Plate II., fig. 12.)
Tubularia ralphii, W. M. Bale, Cat. Austr. Hydroid Zoophytes Austr. Mus. (1884), p. 42.

Localities.—W.Q., February 28th, 1902; —20 fms. Hut Point, October 18th
and November 13th, 1902. Flagon Point, January 17th, 1902; 10-20 fms.

This species is represented in the collection by a group of dead perisarcal tubes
and a single hydranth which is not well preserved, as well as by a few immature
specimens.

Fydrosome.—The height of the colony is from 60-120 mm. In the W.Q.
specimen, five long and slender hydrocauli arise from a contorted hydrorhizal plexus.
Each hydrocaulus is unbranched, and considerably narrower at the base than at the
distal extremity, where its diameter is about 0°8 mm. The perisare covering the
hydrocaulus is smooth and conspicuous, but becomes very thin and transparent at the
base of the hydranth. The hydranth is flask-shaped, and has a dense tuft of distal
tentacles and a circlet of about twenty or more proximal tentacles each about
5 mm. in length.

Gonosome.

The blastostyles arise immediately above the proximal row of
tentacles. Owing to the condition of ‘the specimen, their number could not be
accurately determined.

The ripe gonophores (females only were observed) are somewhat pear-shaped, and
provided distally with four rudimentary tentacles. The walls of the umbrella are very
thin, but the sub-umbrella cavity is large, and usually contains more than one, but not
more than three actinule. No trace of tentacles could be observed on these larvee.

The blastostyles are very short, and the gonophores are borne upon them in dense
clusters, so that it is probable that in life they were not pendulous. The blastostyles
are about 2 mm. in length, and each ripe female gonophore about 1 mm. in length.
The male gonophores of another specimen were not mature.

The only printed description (4: p. 42) of the type of this species which was
found in shallow water in Hobson’s Bay, Victoria, is so short that it is impossible to
be certain that our identification of these Antarctic Tubularias is correct, but, except
in the fact that our specimens are rather larger than the type in several measurements,
there is no good reason for separating them from it.

TUBULARIA HODGSONI.
(Plate II., fig. 13, and Plate IV., fig. 34.)

Locality.—W.Q., January 1st, 1902; No. 6 hole; 130 fms. No. 11 hole,
April 25th, 1903.
Unfortunately, only two zooids of this remarkably interesting species were found.

14 SYDNEY J. HICKSON a AND F. H. GRAVELY.

Fydrosome.

branches ramifying in a sponge. The hydrocaulus is unbranched, and rises to a

The hydrocaulus springs from a hydrorhiza composed of thin

height of about 40 mm. It is of almost uniform diameter throughout.

The perisare is thin, membranous, and ends rather abruptly a little below the
hydranth, which is marked off from the hydrocaulus by a slight constriction. The
height of the cylindrical hydranth is about 5 mm. There is a dense tuft of about
60 tentacles round the mouth. The proximal circlet is composed of about 25 tentacles,
7 mm. in length.

Gonosome.—There are about nine bunches of closely packed spherical gonophores ~
attached in the usual manner to the inner or distal side of the-proximal circlet of
tentacles. From the position they occupy in the spirit specimen lying close alongside
the wall of the hydranth, it seems probable that in life the hydranth was pendulous.
The blastostyles are about 5 mm. in length and the gonophores are 0°9 mm. in
diameter. The structure of the gonophores is extremely interesting. The umbrella
wall consists (fig. 34) of an outer layer of simple ectoderm, a thin layer of mesogloea,
and an inner layer of ectoderm cells, which appear to be tri-radiate in section, one of
the radii projecting into the mass of sperm cells, and the other two radii forming a
continuous thin membrane lining the sub-umbrella cavity. At the distal extremity
of the gonophore the inner and outer ectoderm layers are continuous, and between
them the umbrella wall is thickened and contains a ring of endoderm cells. In some
cases there are four short tentacular thickenings of the ectoderm at the mouth of the
gonophore (fig. 34). In the centre of the gonophore there is a well-marked manubrium
or spadix, with a lumen and without any clearly-defined ectoderm covering. The
sperm cells entirely fill the space between this endodermal spadix and the umbrella.
wall. The sperm cells lying in contact with the manubrium are evidently in the
earlier stages of spermagenesis, those lying at the periphery of the sub-umbrella
cavity in the later stages of spermagenesis (fig. 34, sp.), so that it may be said that
the sperm cells ripen from within outwards.

The absence of any well-defined canals in the gonophore, and the presence of
four conical rudimentary tentacles, suggests aftinities with Agassiz’s sub-genus
Thamnocnidia (1: see 2, pp. 399-400, 406, and 416), but apart from this it is not
possible to find any close affinities with other species of the genus.

TUBULARIA LONGSTAFFI.
(Plate I; fig. 11.)

Locality.—No. 6 hole, April 8th, 1903; 124 fms.

Only a single specimen of this magnificent Tubularian zoophyte was found, and
it bears unfortunately only a single hydranth. As it appears to be quite distinct
from Tubularia hodgsoni and does not agree with any other species of the genus
that has hitherto been described, we propose to call it Tubularia longstaffi.

HYDROID ZOOPHYTES. 15

FHydrosome.—The hydrocaulus is unbranched and about 2 mm. in diameter
at the distal end. It rises to a height of 70 mm. At its base, where it is
extraordinarily slender, there are three or four hydrorhizal branches. It is invested
by a continuous smooth tube of perisarc. At the base of the flask-shaped hydranth
the hydrocaulus is slightly constricted.

Just above this constriction the hydranth expands to form the support of the
proximal circlet of tentacles. The tentacles of this proximal circlet are 25 in
number and about 12 mm. in length. Just above this circlet of tentacles arise the
eight long slender blastostyles.

From the base of the blastostyles the hydranth narrows rapidly to form the
conical hypostome surrounded by a dense tuft of distal tentacles, each about 2 mm.
in length.

Gonosome.—The eight blastostyles are in the contracted condition of spirit
specimens about 14 mm. in length and bear a great number of flattened gonophores.
The gonophores are all female, and about 2 mm. x 2°5 mm. in size. They have
no radial or ring canals, but, like Tubularia hodgsoni, they have four rudimentary
tentacles.

Actinulze with proximal tentacles.

This form appears to be most closely allied to 7. spectabilis (Agassiz) from the
coast of Massachusetts, described by Allman (2: pp. 414-5, see also pp. 416-7), in
size and general form; but as the description is not very full, it is not possible to
determine the identity of the two species with certainty.

It differs, however, from the description of 7. spectabilis in having the
blastostyles disposed in a single row, and not in two or three rows one over the
other.

Moreover, the hydrorhiza of our specimens shows no sign of being “ very
much contorted, irregularly branched, and densely intertwined.”

CoRYNIDAE.
Species A,

Locality.—W.Q., McMurdo Bay, February 20th, 1902; —20 fms.

A single hydranth was found at the bottom of the bottle containing various
hydroids from this locality, which appears to belong to some genus of the family
Corynidae. Without further evidence than we possess at present we cannot even
venture to suggest the name of the genus to which it belongs.

The hydranth is about 0°7 mm. in height, and almost spherical in shape. It
has a conical hypostome and six scattered capitate tentacles. The presence of a
short stolon or stem at the base of the hydranth suggests that the species is
colonial in habit.

No gonophores are present.

16 SYDNEY J. HICKSON anp F. H. GRAVELY.

Species B.
(Plate IIL, fig. 17.)

Localities. —W.Q., Hut Point, November 13th, 1902. W.Q., Hut Point,
September 27th, 1902. East end of the Barrier, January 29th, 1902; 100 fms.

Three specimens of a solitary (?) coryniform hydranth were found in the
bottles containing hydroids from these localities attached to the sponge spicule
débris. The hydrocaulus is 3°5 mm. in length. The hydranth is 2 mm. in height
and 0°6 mm. in diameter, cylindrical in shape, with short scattered capitate
tentacles 0°3 mm. in length. The proximal end of the hydrocaulus is covered by a
chitinous perisare and gives off 3 or 4 hydrorhizal filaments (fig. 17, hrh. f.), for
attachment to the sponge spicule débris. No gonophores are present.

Bonnevie describes a solitary form, Coryne gigantea, from Hammerfest (7: p. 15),
but this species differs from our specimens in having a hydranth longer than the
hydrocaulus and in having the tentacles arranged in groups of three or four
instead of singly.

There is some reason for believing, from the evidence afforded by these
specimens, that at least two species of Corynidae occur in the Antarctic Sea.

This is an interesting conclusion, as no specimens of the family were obtained
by the ‘ Belgica’ or ‘Challenger’ expeditions, nor has the family been discovered
yet in the Falkland Islands. Hartlaub (10: pp. 505-509), however, describes two
species of Coryne, one species of Syncoryne and one species of Gemmaria from the
coasts of Chili, ete.

It is also noteworthy that these few specimens are the only Hydrozoa in the
collection with capitate tentacles ; it is therefore quite certain that they are not detached
zooids from other large colonies that we have found in the collection, and improbable
that they represent initial stages in the life history of these large colonial forms.

FAMILY CORYMORPHIDAE.

The genera belonging to this family that are sufficiently well known to be
generally recognised are Branchiocerianthus, Monocaulus, Corymorpha, Lampra,
Gymnogonos, EHeterostephanus.

The genus Branchiocerianthus (Mark 15 and 16) appears to be perfectly distinct,
and does not offer any difficulties to the systematist. Corymorpha (M. Sars, 1835)
and /leterostephanus (Allman) differ from the other genera in producing in both sexes
free medusiform gonophores. Allman (2: pp. 395-6) introduced the genus Monocaulus
for the species with adelocodonic gonophores described by Sars as Corymorpha glacialis,
and he included in the same genus Corymorpha pendula (Agassiz) and the giant
deep-sea species Monocaulus imperator.

HYDROID ZOOPHYTES. 17

Bonnevie (5: pp. 469-471) in 1898 instituted the genera Lampra and Gymnogonos,
This authoress includes all the species belonging to this group of genera with
“medusoid” gonophores in the genus Corymorpha. All species with ‘“ pseudo-
medusoid” gonophores are placed in the genus Lampra, and those with “styloid ”
gonophores in the genus Gymnogonos.

This classification appears to us to be reasonable and will probably serve a useful
purpose for some years. Ditticulties are sure to arise later when species are found with
intermediate characters, but at present we can recognise three distinct steps in the
degeneration of the medusiform gonophore which may he used for purposes of
classification. There is the “medusoid” gonophore showing some evidence of
degeneration, but retaining the endocodon or sub-umbrella cavity, the ‘“ pseudo-
medusoid ” gonophore retaining the umbrella wall, but with no sub-umbrella cavity ;
and, lastly, the “styloid” gonophore with little or no definite trace of medusoid
structure.

LAMPRA PARVULA.

(Plate IIIL., figs. 15, 16; and Plate IV., fis, 35.)

Localities. —Off Hut Point and Flagon Point in McMurdo Bay. Sexually mature
and full-grown specimens obtained from September to December, 1902, and September,
1903. Young specimens obtained January, February, March and October, 1902, and
January, 1903. Depth, 10-20 fms.

A great many specimens of this interesting little species were found in several
tubes and bottles from the localities named above. They are attached by root-like
processes from the basal end to polyzoa (fig. 15) and to a curious felt-work mass of
substance that is mainly composed of sponge spicules (fig. 16). Although Lampra
parvula presents us with the largest hydroid zooid, except those of LZ. microrhiza and
of Tubularia in the collection, yet they are considerably smaller than the zooids of any
known species of Lampra or Corymorpha. The zooids of the only known species of
Gymnogonos, however, are only 10-20 mm. in height. Like many other species of
Corymorphidae, the colour of the spirit specimens is dark reddish-brown.

In habit the species closely resembles Lampra socia (Swenander, 238: pp. 6-8,
figs. 1-2) from the Trondhjem fjord, several specimens being usually found in groups
more or less imbedded in the sponge débris mass. A few very young specimens were
found attached singly to the stems of calcareous polyzoa (fig. 15), or more rarely to
other hydroids. L. socia was found attached to the branches of Lophohelia prolifera.

Hydrosome.— The height of the full-grown polyps from the base to the mouth is
about 30 mm.

In a great many specimens (fig. 16) there is a sudden diminution in the diameter
of the polyp about half the distance from the base to the tentacles. The position of
the constriction varies a good deal in different specimens, and in some it is hardly
noticeable, the stems gradually tapering from the base to the neck. The thicker basal

VOL, Ill. ZE

18 SYDNEY J. HICKSON anv F. H. GRAVELY.

portion of the polyp is invested by a fairly thick pellicle of very different appearance
from the typical perisare of the Tubulariidee. In many specimens, which have perhaps
shrunk in the preservation, the pellicle is only loosely attached to the body wall.

The distal tentacles are very numerous (60-70) and about 1°5 mm. in length.

In the proximal ring there are about 30 tentacles, each about 10 mm. in length.

Gonosome.—The gonophores are situated in compact bunches in close proximity
to the inner aspect of the proximal circle of tentacles (fig. 16). They are almost
spherical in shape, the female gonophores being about 1 mm. and the male
gonophores 0*8 mm. in diameter.

As in other species of the genus, they are “ pseudo-medusoid” in character (fig. 35).

In many specimens ova (fig. 35, ov. rup.) may be seen somewhat constricted in
the middle and obviously rupturing the wall of the gonophore. Bonnevie (6: p. 21)
states that in Lampra sarsii the ova “leave the gonophores at a very early stage
of their development and remain for a time attached to the mouth of the gonophores.”

LAMPRA MICRORHIZA.
(Plate II, fig. 14.)

Locality :—Off the Barrier, January 27th, 1902; 300 fms.

Though small as compared with other Corymorphidae, this is by far the largest
hydranth of the collection.

Unfortunately, the two specimens obtained are in a very bad state of preservation,
and although sections of the mass of tissues in the position of the blastostyles have
gonophore

fo)
structures. It is mainly on account of the dark brown colour that these specimens

been made, it has been impossible to demonstrate with certainty any

are referred to the genus Lampra.

Hydrosome.—TVhe hydrocaulus rises to a height of 50-60 mm. ; it is about 3 mm.
in diameter throughout, and proximally is loosely covered by a thin chitinous pellicle
(fig. 14, c. p.); at the proximal end it gives off a very large number of extremely
delicate processes for attachment (fig. 14, Arh. f.). The hydranth is not separated
from the hydrocaulus by a constriction. The proximal tentacles are 40-50 in number
and about 40 mm. in length; the distal tentacles appear to be about 7 mm. in length,
but are matted together and cannot be clearly seen in the preserved specimens.

Gonosome. —Blastostyles branched ; 5 (?) mm. in length.

FAMILY MYRIOTHELIDAE.
(MyrioTHELa ?)
(Plate III, fig. 18.)
Locality :—W.Q., Hut Point, November 13th, 1902.
A single specimen of a hydroid belonging probably to this family was preserved
in a separate tube from this locality.

HYDROID ZOOPHYTES. 19

Hydrosome.—A solitary zooid. The hydrocaulus is about 8 mm. in height and
about 2 mm. in diameter for the greater part of its length. At the base it is much
thinner and gives off numerous hydrorhizal filaments (fig. 18, Arh. 7.) for attachment
to the sponge spicule débris. It is covered throughout its length by a thin chitinous
perisare with transverse striations.

The hydranth is naked, about 6 mm. in length, and spindle-shaped, thickening
gradually from the hydrocaulus, and then gradually tapering to form the conical
hypostome. The distal half of the hydranth bears numerous short, thick, scattered
conical or hemispherical tentacles (fig. 18, ¢.) the largest of which are situated just
above the thickest part of the hydranth.

Gonosome.—-No gonophores are present.

Although we are unable to give a generic or specific name to this specimen, we
are anxious to record the existence of a member of this family in the Antarctic Sea.
Hartlaub, in his summary of the Southern Hydroids, does not mention the family at
all, but Jiiderholm (13: p. 2.) records the occurrence of Jf austro-georgiae from
South Georgia.

FAMILY SERTULARIIDAE.
SERTULARELLA SPIRALIS.
(Plate III., figs. 19, 20.)

Locality. W.Q., No. 10 hole, July 3rd, 1903; 130 fms.

Several fine colonies of this species were obtained from this hole at the date
given above. It is perhaps noteworthy that no other specimens were obtained from
any other localities, although at this particular spot the species seems to have
been so abundant. Unfortunately, all the colonies were torn away from their
attachments, so that in some particulars our description must be imperfect.

Hydrosome.—The slender monosiphonic hydrocaulus is 250 mm. or more in
height. It is bent alternately right and left at intervals of 5 mm., and at each
geniculation two branches are given off from the major angle. Each of these
branches is about 40 mm. in length, slightly geniculated and pinnately branched,
the pinnules arising as before from the neighbourhood of the angles. Their internodes
are about 2°5 mm. in-leneth. In some cases one or both of the branches themselves
are elongated to form an axis similar to the main axis and give rise to secondary
branches similar to the primary branches.

The general effect of this method of ramification is to give the appearance of
a spiral form similar to that so characteristic of the genus //ydra/limania.

The pinnules vary in length up to 30 mm. and are divided into a series of
internodes by geniculations, but these internodes are not all of the same length
(0°6-1°0 mm.), increasing somewhat in length in the distal parts. Proximally the
nodes are not very clearly marked.

bo
ic]
bo

20 SYDNEY J. HICKSON anp F. H. GRAVELY.

Each internode of a pinnule bears one hydrotheca at its distal extremity, but
each internode of a branch bears three hydrothecze, one at the distal extremity, and
the other two at intervals of one-third and two-thirds from the proximal end.

The hydrothecee of the pinnules (fig. 19) are about 0°5 mm. in depth, 0°22 mm.
in their greatest diameter, and 0°17 mm, in diameter at the mouth, and have three
opercular flaps (fig. 19, op.) 0°09 mm. in length. They are somewhat shorter than
this in the proximal regions of the pinnules. The two proximal hydrothece of
the internodes of the branches are decidedly shortened as regards that part of
their length which is not adnate. The distal hydrotheca of each internode of the
branches is nearly straight and barrel-shaped. A single straight hydrotheca, which is
not adnate to any part of a hydrocaulus, is situated between the bases of each pair of
branches (fig. 20, /th.). Apart from these, the main axis bears no hydrothece.

A remarkable feature of the hydranths is the presence of a loose sheath of
ectoderm (fig. 19, ect.) enveloping the base. The hypostome is conical and
surrounded by about fifteen tentacles.

Gonosome.—Only female gonothece (fig. 19, gth.) have been observed. They
are 1:0 X 0°5 mm. in size, ovate, smooth, sessile, and attached below the bases
of the hydrothecee of the pinnules. The gonothecze are all empty, none of the
gonophores being preserved. The planulz are developed in spherical or somewhat
pear-shaped acrocysts (fig. 19, ae.), 0°4 mm. in diameter.

This species seems to be quite distinct from any that has yet been described.

SERTULARELLA PLECTILIS.
(Plate IIL, fig. 21.)

Localities.—W.Q., No. 6 hole, February 15th, 1902; 130 fms. W.Q., McMurdo
Bay, February 20th, 1902; 20 fms.

Several large, detached, tangled masses of this hydroid were found in the first-
named locality; but in the second locality only a single small colony 12 mm. in
height attached to the stem of Campanularia verticillata was obtained.

LHydrosome. —The hydrocauli are all extremely slender, not exceeding 0°12 mm.
in diameter, irregularly branched, and—as they reached us—in an inextricable tangle.
The internodes are about 0°6 mm. in length. The branches arise immediately below
the hydrothece (fig. 21). A single hydrotheca is situated at the distal end of
each internode. As many of them are reduplicated (fig. 21, 7. /th.), they vary
considerably in length. The original length of each hydrotheca appears to be
0°4 mm., but one showing four reduplications is 0°6 mm. The greatest diameter
is 0°15 mm., and at the mouth 0°13 mm. The wall is adnate to the hydrocaulus
for about one-third of its original length. It is extremely thin. The margin has
three opercular flaps, 0°06 mm. in length. About fifteen tentacles surround the
bluntly conical hypostome of the hydranths.

HYDROID ZOOPHYTES. wAAl

Gonosome.—The gonothecee (fig. 21, gth.) are immature and about 0°5 x 0°4 mm.
in size. They are all female. They arise from the hydrocauli immediately below
the hydrothece and are sessile. They are smooth, pear-shaped, and have a straight
margin. No gonophores can be seen, the ova being embedded in the blastostyles.

This species is also quite distinct.

DicryocLADIUM FUSCUM.
(Plate TIl., fig, 22.

Locality—Cape Wadworth, Coulman Island, January 15th, 1902; 8-15 fms.
Bottom stones.

Hydrosome.—The single specimen of this species forms a thick, shrubby, fan-
shaped colony, 90 mm. in height, 80 mm. in width in the widest part, and about
25 mm. thick, i.¢., in a direction at right angles to the line of greatest width and the
line of height. The principal branches arise irregularly from the main stem, but
the smaller and ultimate branches are flabellate in their mode of ramification.
The colony as a whole is rendered more compact than it otherwise would be by
the ends of several branches developing stolons (fig. 22, sf.) which attach themselves
to other branches around the bases of their whorls of hydrothece. At the base
the colony is polysiphonic, but distally the branches are all monosiphonic. The
base and hydrorhiza are missing.

The hydrothece (fig. 22, Ath.) are arranged in six rows and almost always in
regular verticels of three, but sometimes the three hydrothece of a verticel are not
quite on the same plane. They are about 0°8 mm. in length and 0°3 mm. in
diameter, and adnate for about one-half to two-thirds of their length. They are
very slightly constricted towards the opening, the margin is quite plain and often
suddenly everted quite close to the edge. Reduplication of the hydrothecie frequently
occurs, but the secondary thece project very little beyond the margin of the
primary ones.

The soft parts are quite macerated.

The general colour of the colony is pale brown.

Gonosome.—Unknown.

The species. differs from Professor Nutting’s diagnosis of the genus (19: p. 105)
in the absence of any operculum. In the type species of the genus (D. dichotomum,
Allman ; 3: pp. 76-77; Pl. 36, figs. 2, 2a) the anastomosing stolons coalesce with
the mouths of the hydrothece, the cavities of the hydrothecw and stolons being
continuous ; but in our species these stolons always grasp the hydrocauli at the base
of the verticels of hydrothece. The species differs from both D. dichotomum of
Allman and PD. flabellum of Nutting in the shape of the hydrothecee and in other
characters. Unfortunately Allman does not mention whether an operculum is
present in his species or not.

bo
bo

SYDNEY J. HICKSON anp F. H. GRAVELY.

FAMILY PLUMULARIIDAE.
PLUMULARIA GLACIALIS.
(Plate III, figs. 23, 24.)

Locality.—* Kast end of Barrier,” January 29th, 1902; 100 fms.

From the nature of the hydrorhiza, which was curved, it seems probable that
the specimens of this species were attached to a weed or zoophyte.

Llydrosome.—A_ stout fascicled hydrocaulus (fig. 23) 300 mm. in height and
2*5 mm. in diameter near the base arises from the densely matted but imperfectly
preserved hydrorhiza.

In the constitution of the hydrocaulus there is a single tube (fig. 23, 4. hel.)
giving off, alternately right and left, hydrocladia which may be 30 mm. in length
and are usually divided into two equal branches. Supporting this single tube that
bears hydrocladia are several other tubes (¢. sp.) which bear nematophores only. The
supporting tubes do not surround the hydrocladia-bearing tube, but leave it exposed
on one side. The hydrocladia-bearmg tube is divided into a series of internodes
1 mm. in length, and it becomes free from its supporting tubes at the distal end, so
that the hydrocaulus then becomes monosiphonic. In Plumularia profunda (Nutting,
18: pp. 66-67; Pl. VIIL, figs. 2-3), to which our species has some affinities, the
supporting tubes entirely surround the hydrocladia-bearing tubes, and the internodes
are of two kinds, longer ones supporting two hydrocladia and shorter ones bearing’
only one hydrocladium. Moreover, in Plumularia profunda the hydrocladia are
supported on processes arising from the proximal end and not from the middle of
the internodes as they are in our species.

A short hydrotheca (0*2-0°3 mm. in height), adnate to the hydrocaulus but
not adnate to the hydrocladium, is found at the base of each hydrocladium (fig. 23).
The other hydrothecee are cup-shaped, 0°3 mm. in length and 0*2 mm. in diameter
at the mouth. One, or sometimes two, arise from each internode of the hydrocladia,
and each one is guarded by two nematophores above (ic. distally) and a single one
below. The margins of the hydrothece are entire.

Although the label of the bottle contaiming these specimens bears the inscription
has been dry,” some of the hydranths are sufticiently well preserved to enable us
to make out some features of the structure of the soft parts. The rounded hypostome
is surrounded by a single circlet of about fifteen tentacles, each about 0°15 mm.

ce

in length.

Gonosome.—The female gonothecee are 1°0 x 0°5 mm. in size, and have a
remarkable shape (fig. 23, @ gth.). The aperture is found on the distal flattened
end of the pear-shaped structure, but instead of being at right angles to the stem,
is turned inwards through an angle of 45° so as to face inwards and upwards. This

HYDROID ZOOPHYTES. 23

inversion of the distal end of the gonotheca is also seen, but to a less degree, in
Nutting’s figures of P. profunda. y

The male gonothece (fig. 24, d gth.) are narrow and bluntly ovate. They are
not found on the same colonies as the female gonothecse. They are 1:0 x 0°4 mm.
in size.

Hach of the female gonothece contains one ovum. In /. profunda, however

b]

ied

the gonothece contain “‘a number of developing ova” (Nutting, 18: ps. 645

Pl. VIIL., fig. 3). .

FAMILY CAMPANULARIIDAE.

The character which distinguishes the hydrosome stage of the Campanulariidac
from the Sertulariidae and Plumulariidae is the presence of a stalk supporting
the hydrothecee and gonothece. It is true that in sub-family Lafovinae no clear
distinction can be drawn between the base of the theca and the stalk of the theca,
theca and stalk forming a continuous tube, but there are other reasons for associating
this sub-family with the Campanulariidae.

The separation of Obelia and its allies from the Campanulariidae is, perhaps,
an unsatisfactory feature of our classification, as there is no important difference in the
hydrosome stage of many of the Hucopidae and that of many of the Campanulariidae.
The Lucopidae have, it is true, free swimming medusiform gonophores and the
Campanulariidae have not, but, as has been shown by several authors, this distinction
is not one which, in the Gymnoblastea, can be used even for generic diagnoses. It
is certainly doubtful whether it ought to be used as a family character in the
Calyptoblastea.

SUB-FAMILY CAMPANULARIINAE.
CAMPANULARIA VERTICILLATA (Linn.), var. grandis.

(Plate IV., fig. 25.)

5

€
(2

Sertularia verticillata, Linneeus, Syst. Nat., X. (1758), p. 811.
Canpanularia verticillata, Hincks, British Hydroid Zoophytes (1868), p. 167, pl. xxxii., fig. 1.

Loealities.—McMurdo Bay, W.Q., February 20th, 1902; 20 fms. Flagon Point,
January, 1903; 20 fms.

This magnificent new variety of Campanularia verticillata was obtained in great
quantities on a large brittle worm tube, 400 mm. lone by 5 mm. in diameter, from
McMurdo Bay, and a small specimen from Flagon Point.

Hydrosome.—The worm tube is thickly covered with a hydrorhizal plexus giving
off at frequent intervals polysiphonic hydrocauli, which attain to a height of 170 mm.
and a thickness of 2 mm. at the base. The hydrorhizal plexus also bears scattered

polyps of the same type as those borne by the hydrocauli. In addition to the
specimens still attached to the worm tube an enormous number of loose broken

24 SYDNEY J. HICKSON anp F. H. GRAVELY.

hydrocauli were found in the bottle. These may have formed part of the colonies
attached to the worm tube, and therefore our estimate of 170 mm. for the height of
the colony may be considerably less than it should he.

The colonies branch irregularly and rather sparingly, and the hydrocauli are
polysiphonie to their distal extremities. At these extremities there appear to be four
to six parallel but anastomosing tubes, each of which bears a single hydranth at
regular intervals, and as the hydranths of the tubes arise at the same level, they
form a series of verticels round the hydrocaulus.

In tracing these tubes down towards the hydrorhiza other tubes appear, which
creep over the primary tubes in an irregular manner and bear hydranths at less
regular intervals. In the lower parts of the stem (fig. 25) the secondary tubes are
more numerous, and play an important part im building up the substance of the
thick base.

In some eases stolons in place of hydranths occur in the verticels of the primary
stems. These may perhaps give rise to the secondary branches. Single tubes bearing
hydranths and gonophores also occur climbing over polyzoa epizoic on the main
hydrocaulus.

The bell-shaped hydrothece are 0°6 mm. in length and 0°4 mm. in diameter
at the mouth. The pedicel of the hydranth is about 1°5 mm. in length, marked
throughout its whole length by a spiral groove. The hydranths have 28-34 tentacles,
arranged in a double row, and each about 0°3 mm. in length. The gonothece are
at first 0°8 x 2°5 mm. in size and pear-shaped, but later, when fertilisation has
been effected, become flask-shaped and 0°6 x 3°0 mm. in size. They are supported
by short spirally marked pedicels.

The specimens differ from the type specimens of the species in the greater size
of the hydrocauli, hydranths and gonophores, in the greater regularity of and greater
intervals between the verticels of the hydranths, i the well-defined spiral marking
of the pedicels, and in the extreme tenuity of the edges of the hydrothece, which
renders it impossible to determine with certainty whether the margin is or is not
dentate, as it is in the type.

Although Campanularia verticillata is a common species in European waters, it
is not included in Hartlaub’s list of Southern species (10: pp. 505-509).

CAMPANULARIA EVERTA.

Campanularia everta, Clark, Trans. Conn, Acad., III. (1876), p. 253.
Campanularia everta, H. B. Torrey, Univ. California Public., Vol. I. (1902), pp. 51, 52, pl. iv., figs. 35-37.

Localities. —W.Q., McMurdo Bay, February 20th and 28th, 1902; 20 fms. W.Q.,
Duct, July 15th, 1902.

This species has been previously described from the Pacific coast of N. America.
According to Mr. Torrey it is extremely variable (24: pp. 51-52).

HYDROID ZOOPHYTES. 25

It was found in our collection growing on other hydroids, such as Halecium
arboreum, and also on algee and polyzoa. It is in some cases continued beyond its
support as a tangle of contorted tubes.

Hydrosome.—Unbranched hydrocauli arise from the branching filiform hydrorhiza
at intervals to a height of 2°5-10°0 mm. They are usually irregularly annulated
above and below, and there is always one well-marked convex annulus immediately
below the neck of the hydrotheca. According to Torrey this subthecal annulation
constitutes the only constant character of the species (24: p. 51).

The hydrotheca is bell-shaped and very constantly 1 mm. in length, but varies
considerably in diameter at the distal end (0°4—0°7 mm.) as well as in outline. The
margin is usually entire, but may be dentate.

The material was not in a good state of preservation, but apparently the
hydranths have about 15 tentacles about 0°6 mm. in length.

Gonosome.—The gonothecee are pear-shaped (1°0 x 0°8 mm.) and supported by a
spirally marked pedicel rising from the hydrorhiza. The gonophores are apparently
female, but being badly preserved, details of their structure could not be made out.

We have some hesitation in assigning these specimens to the species C. everta of
Clark, as they differ in many respects from the original description of the type. But
assuming that Mr. Torrey is correct in his statement that the species is very variable,
and comparing our specimens with his figures and description, the course we have
adopted appears to be a better one than that of founding for them a new specific name.
The specimens are clearly more closely related to C. everta than to C. integra, or any
other species of the genus.

CAMPANULARIA LAEVIS.
(Plate IV., fig. 26.)
Campanularia laevis, Hartlaub, C., Zool. Jahrb., Supplement VI. (1905), p. 565.

Localities.—W.Q., February 28th, 1902. McMurdo Bay;— 20 fms. W.Q.,
February 23rd, 1902, Flagon Point.

Several colonies of this very beautiful hydroid were found creeping on the stems
of Halecium arboreum. The zooids are, with the exception of those of its supporting
species, the largest among the Calyptoblasts of the Expedition, and the large bell-shaped
hydrothecee with toothed margins—mounted on their straight but graceful pedicels—
are very striking.

Hydrosome.—The creeping hydrorhiza gives rise at intervals to a number of
straight, upright, unbranched hydrocauli from 5 to 10 mm. in height. Each
hydrocaulus has two or three very obscure annulations at the base, and one clearly
marked convex annulation immediately below the hydrotheca.

The hydrotheex are bell-shaped, slightly curved at the base, and then straight,
expanding gradually throughout their whole length. They are from 2°5-3°0 mm. in

VOL, III, 2p

26 SYDNEY J. HICKSON anp F. H. GRAVELY.

length, and from 1°5-2°0 mm. in diameter at the mouth. The margin is armed with
15-20 blunt denticulations. The hydranths are large, but of the usual form in the
genus, and provided with about 30 tentacles 1°5 mm. in length.

Gonosome.—The mature gonotheca is 2°5 x 1°2 mm. in size, tall and cylindrical.
The proximal part of the gonotheca is slightly swollen, and the distal end almost
straight. It is supported by a short annulated pedicel arising directly from the
hydrorhiza.

The specimens attributed to Hartlaub’s species differ from the type in one or two
particulars. The hydrothece are not so fully expanded distally, the reduplications (?)
of the stem are not so well-marked, and the gonothece are very different in shape
from those of the specimens from Calbuco.* But without further evidence as to the
sex and structure of the gonophores of this type we do not feel justified in creating a
special specific name for them.

SUB-FAMILY HALECIINAE.

The genera that are usually included in the sub-family /Halectinae (Haleciidae,
Hincks) are characterised by the rudimentary condition of the hydrothece. The
tubular structures arising from the hydrocladia surround, like a collar, the base of the
hydranths, but are quite insufticient to enclose and thereby afford protection to them
when retracted. ,

It is, in our opinion, unfortunate that the term ‘“ hydrophore” has come into
general use for this rudimentary form of hydrotheca. There are many examples to be
found in the Calyptoblastea of hydrothecee that are not cup-shaped, such as the
cylindrical hydrothecee of Sertularella formosa and Synthecium cylindricum , (see
Nutting, 19: p. 14), and it would be practically impossible to limit the use of the term
to hydrothecz, that are tubular or cylindrical in shape. The use of the term hydro- -
phore for those hydrothecee only which are not capable of receiving the retracted
hydranth would also be inconvenient. It is, therefore, the best course to adopt to
abandon the use of the term hydrophore altogether.

The genus //alecium is usually regarded as distinguished from its allies Dip-
locyathus (Allman), Hydrodendron (Sars), and Ophiodes (Hincks) by the absence of
nematophores ; but one of us has observed the presence of nematophores on the
specimens of J/alecium arboreum obtained by the ‘ Challenger’ (8: p. 10, Pl. IV.,
figs. 1-3) and now in the British Museum, which were overlooked by Allman, and the
specimens which we attribute to the same species have also nematophores. It does not
seem to us convenient to again split up the genus //aleciwm into groups containing
those which do and those which do not possess nematophores, but rather to add to the
characters of the genus, that ‘‘ nematophores may or may not be present.” As regards
the use of the term “ nematophore,” it is necessary to explain that we have adopted the

* On the coast of Chili, approximately 41° S. by 71° W.

HYDROID ZOOPHYTES. 27

-plan of regarding it as synonymous with “sarcotheca” and applicable only to
perisarcal skeleton. The zooid which the nematophore envelopes (in the case of
. Halecitum only very partially) appears to us to be a true dactylozooid, and we have
not adopted the use of any of the terms

‘

‘sarcostyle,” ‘‘ machopolyp,” “ sarcodal
q 7? Re > warl x rq wa
process,” etc., suggested by various writers.

ce

The occurrence of the gonothecee in “ coppinia” masses in our specimens of
Talecium arboreum is a feature of some interest. The number of genera in which this
grouping of the sexual zooids occurs is extending as our knowledge advances.

The gonothece of the specimens of [alecium arboreum and IL. telescopicuin
obtained by the ‘Challenger’ were not observed, but the gonothece of //. jlevile,
II. dichotomum, IT. fastigeatum, H. beanii and HH. cymiforme obtained by the same

ee

expedition were not in “coppinia” masses. This peculiar grouping of the gonothecze
is not, therefore, a character of the genus, but may indicate a method for the future

rearrangement of the species into subgeneric groups.

HALECIUM ARBOREUM.
(Plate IV., figs. Dien 29")
Halecium arboreum, Allman, ‘ Challenger’ Reports, Vol. XXIII. (1888), pl. iy., figs. 1-3.

Localities.—The species is evidently abundant in McMurdo Bay, extending from
shallow water to depths of 130 fms.

W.Q., McMurdo Bay, February 20th and 28th, 1902;—20 fms. W.Q., Flagon
Point, January 17th and February 23rd, 1903; 10-20 fms. W.Q., No. 6 hole,
January 31st, 1903; 130 fms. W.Q., February 21st, 1902; 10 fms. W.Q., off
cable, February 17th, 1904. Kast End of Barrier, January 29th, 1902; 100 fms.

The specimens of this species consist of a number of robust colonies rising to a
height of 300 mm. from a thick hydrorhizal plexus. A few small colonies from the
east end of the Ice Barrier were found attached to the stems of Plwinularia,

Hydrosome.—The hydrorhiza is a dense plexus of tubes exhibiting a tendency to
be grouped together in polysiphonic bundles.

The main stem is a thick polysiphonic hydrocaulus 10 mm. in diameter.

The proximal branches are polysiphonic, like the main stem, and anastomose freely
whenever they come in contact with one another. The distal branches are much more
‘numerous and usually monosiphonic. The monosiphonie branches (fig. 27) alone bear
the hydrothecee, but in some cases these branches still bear hydrothece after the
addition of the first few strengthening tubes.

The ramification of the distal branches is pinnate, and in other parts of the colony
it is roughly, but not rigidly, flahbellate.

The thickness and roughness of the stem and of the principal branches afford
admirable support for the hydrorhize of other hydroids, a list of which will be found
on page 1.

~
~

Z8 SYDNEY J. HICKSON ann F. H. GRAVELY.

Up to a height of about 150 mm. the colony consists of only four or five thick
(7 mm. in diameter) and occasionally anastomosing stems, bearing a few thinner
(3 mm. in diameter) branches which are themselves pinnately branched. Above this
recion the thick stems branch much more profusely and somewhat pinnately, bearing
numerous thinner branches whose method of further ramification is always pinnate.

The ultimate branches (hydrocladia) are jointed, the internodes being 0°6-1*1 mm.
in length and about 0°4 mm. in diameter. Each internode hears on one side a single
hydrotheca (hydrophore) adnate throughout its whole length, and supporting the
base of a hydranth 2 mm. in length (fig. 24, /yd.), and on the opposite side a long
serpentine dactylozooid (sarcostyle) 1°5 mm. in length and about 0°15 mm. in
diameter (fig. 24, d.), supported at the base by a nematophore (sarcotheca) 0°15 mm.
in length and about 0°15 mm. in diameter.

At the extremity of the dactylozooid there is a battery of nematocysts. In the
specimens many of the dactylozooids and nematophores are broken off, but there is
little doubt that they are usually, if not regularly, present in the living colony in the
position assigned to them. The dactylozooids are very similar to those figured by
Hincks for Ophiodes mirabilis, although not so clearly “ knobbed” at the extremity.

The hydranths are of the typical //alecium form. The hypostome is surrounded
by a circle of about twenty tentacles each about 0°5 mm. in length.

Gonosome.—The gonothecee together with some nematophores occur in
“ coppinia” masses (fig. 28) on the stem and branches. These ‘“coppinia” masses
are oval or spherical, densely branched and tangled clumps, 25 x 25 mm. to
60 x 30 mm. in size, having a rough resemblance to the “ bedeguar” galls on the
stem of the wild rose. The delicate dichotomously ramified branches of these
masses bear dactylozooids and nematophores (fig. 29, d. and nph.) similar to those of
the other parts of the colony, and numerous paired gonothece (fig. 29, gth.),
1:0 x 0°7 mm. in size, which curve sharply backwards, terminating in a hook-like
process at the extremity of which is the gonothecal mouth.

The type of this species was found at Kerguelen in 1874.

H{ALECIUM TENELLUM.
Halecium tenellum, T. Hincks, Brit. Hyd. Zoophytes (1868), p. 226, pl. xlv., fig. 1.

Localities. —W.Q., McMurdo Bay, February 20th, 1902;—20 fms. W.Q., Flagon
Point, January 17th, 1903; 10-20 fms. W.Q., Flagon Point, February 23rd, 1903.
W.Q., off cable, February 17th, 1904. W.Q., D net, June 15th, 1902.

This widely distributed little //alecitum appears to be fairly common in
McMurdo Bay. It is found on sea-weed, Alcyonium paessleri, on Halecium arboreum,
and on other hydroids. ;

Hydrosome.—The delicate little colonies are about 10 mm. in height and
spring from a creeping hydrorhiza. The hydrocauli are monosiphonic, irregularly

HYDROID ZOOPHYTES. 29

annulated and very irregularly branched. They are not more than 0°1 mm. in
diameter.

The hydrothecse are elongated and everted at the margins. They are
frequently reduplicated.

The hydranths are 0°5 mm. in length and have about 20 tentacles 0°25 mm.
in length. There are no nematophores in this species.

Gonosome.—The gonothecse are oval (0°8 x 0°5 mm.) or spherical in both
sexes. They are situated on short pedicels which may be irregularly annulated as
in the British type. They are situated on the hydrocauli in no definite position.
There is no evidence of any “coppinia’-lke grouping of the gonothece.

The species Halecium tenellum was obtained by the ‘ Belgica’ expedition in
70° S. by 91° W., and Bale mentions that he has one specimen in his collection
from the Australian waters. It has also been found on the south Fuegian coasts
and in Smyth Sound (10: pp. 505-509). It is common on the British and
American coasts and extends into the Arctic seas (Jan Mayen). In fact, it appears
to be cosmopolitan in Arctic and Temperate seas.

SUB-FAMILY LAFOEINAE.
LAFOEINA LONGITHECA.
(Plate IV., fig. 31.)
Lafoéina longitheca, Jéiderholm, Arch. Zool. Expér. (4), II. (1904), p. iv.

Locality—McMurdo Bay, February 20th, 1902; 5-20 fms.

Two small colonies of this hydroid were found creeping on the free hydrorhiza
of Perigonimus antarcticus.

Hydrosome.—A. well-developed hydrorhizal filament is attached to the support.
From this there arise at intervals tall, cylindrical hydrothece (fig. 31) 0*7-1°0 mm.
in height, slightly annulated at the base, and gracefully everted at the margin.
The margin bears about twelve opercular flaps (fig. 31, op.), 0°11 mm. in length.
Occasionally secondary hydrothece arise from the primary ones and attain an
additional length of 0°25 mm. There is no distinct pedicel, the diameter of
the hydrotheca at the base being almost as great as it is at the distal extremity.

The hydranths are very small, being in the contracted condition not more than
0:4 mm. in length, or about half that of the hydrotheca. A circlet of about eight
tentacles surrounds the blunt conical hypostome. Each tentacle is about 0°15 mm.
in length.

Numerous upright nematophores, 0°12 mm. (but occasionally 0°2 mm.) in height
by 0°02 mm. in diameter, arise independently from the hydrorhiza. They contain a
delicate thread of tissue (fig. 31, d.), terminating in a pad at the extremity which
is armed with a battery of nematocysts.

Gonosome.—Not observed.

30 SYDNEY J. HICKSON anp F. H. GRAVELY.

The type of this species was found in South Georgia, in depths of 64-250

metres, and although the author gives no figures, we have no doubt of the identity

oO

of our specimens with the type.

FAMILY EUCOPIDAE.
GENUS OBELIA.
Obelia geniculata.
(Plate IV., fig. 30.)

Sertularia geniculata, Linneeus, Syst. Nat. X. (1758), p. 812.
Obelia geniculata, Hincks, Brit. Hyd. Zooph. (1868), p. 149, pl. xxv., fig. 1.

Locality.—Auckland Islands, off Port Ross, March 28th, 1904.

This very widely distributed species was found in the material obtaimed from
the Auckland Islands. Jt has previously been described from numerous localities
north and south of, but not within, the tropics (10: pp. 505-509; 3: p. 23;
Apo):

It is the only species of Hydrozoa in the collection that we have proved to
be phanerocodonic, and it is on that account noteworthy that, notwithstanding the
rich and varied hydroid fauna that was brought to hght by the Expedition, not a
single specimen of this species was found under the ice in McMurdo Bay.

A considerable number of luxuriant colonies were found growing on the frond
of a Laminaria.

Dimensions.

The height of the largest colony. : . 30 mm.

Height of hydranths . : ; » O° 4mm:

Length of pedicels of hydranths . : . 0:25am:

Size of gonothece . : ‘ ‘ - O°9 * 0°25 mm:
Length of tentacles . : : ; . O°4 mm.

The specimens differ from the common British’ type of the species in having
two (instead of one) annular constrictions in the perisare of the hydrocaulus above
each flexure. They also grow more luxuriantly and branch much more freely than
the British type.

Hydrosome.—Stem zigzag, sometimes pinnately branched, two deep constrictions
of the perisare above each flexure. The perisare below each flexure very thick,
forming a series of projections from which the short annulated pedicels arise.
Hydrothecz conical, somewhat longer than they are broad, margin entire, perisare
thick. Tentacles of the hydranth about 30 in number. Gonothece axillary,
urn-shaped, attached by a short annulated pedicel.

Gonosoine.-—HKach blastostyle bears numerous young scattered medusze.

HYDROID ZOOPHYTES. 31

GENUS CAMPANULINA.

The genus Campanulina was instituted by Professor E. van Beneden for a species
that is known to produce one of the meduse of the genus Phididium. The
hydrosome stage is characterised by the conical hydrotheca closed by an operculum
formed of convergent segments of its margin and by the conical hypostome.

The specimens obtained by the ‘ Discovery’ have all the important characters
of the hydrosome thus described, and so have the specimens described by Dr. Hartlaub
(9: pp. 10-11; Pl. I, figs. 8-9) under the name Campanulina belyice, from within
the Antarctic Circle.

The absence of the gonophores in both specimens. rendered it impossible for us
to determine whether they are or are not phanerocodonic. Even if they had proved
to be adelocodonic, however, they should in our opinion be still retained in the
genus Campanulina, as the case of Perigonimus antarcticus may serve as a warning
that the setting free of the meduse is not a character that can be used as
absolutely diagnostic of a genus when applied to these sub-glacial species. It is
interesting to note in this connexion that Mr. Hodeson (12: p. 397) states that
Phialidium meduse were abundant in McMurdo Bay.

CAMPANULINA A.

Locality —MecMurdo Bay, February 20th, 1902; 5-20 fathoms.

A single colony of this delicate little hydroid was found growing over a stem
of Halecium arboreum and over the Perigonimus antarcticus which encrusts it.

LHydrosome.—The hydrocauli are slender (0°05 mm. in diameter and 0°5-1 mm.
in length), more or less clearly marked throughout with spiral lines, and very
occasionally branched. They arise from a creeping

The perisare at the distal ends of the hydrocauli gradually dilates to form the
“ovato-conic” hydrothece, 0°4 mm. in length by 0°1 mm. in diameter. The
hydrotheca itself is very thin and evidently very flexible. Its margin is deeply cleft
to form about eight triangular flaps (0°1 mm. in length), which can close together

filamentous hydrorhiza.

to form an operculum. It is difficult to determine with any certainty the exact
number of these flaps, as they are extremely thin and transparent.

The hydranths, when contracted, completely fill the hydrothecee. The hypostome
is conical and surrounded by a single circlet of about twenty tentacles, 0°2 mm.
in length. -

Gonosoime.—-Unknown.

CAMPANULINA B.

Locality.—McMurdo Bay, February 20th, 1902 ; 5-20 fathoms.
A single small colony of this form was found on Campanularia verticillata

(var. grandis).

wy)
bo

SYDNEY J. HICKSON anp F. H. GRAVELY.

ITydrosome.—Only a few hydrocauli of this very small form were found.
They are about 0°1 mm. in length by 0°06 mm. in breadth, and arise from a
filamentous hydrorhiza. The hydrocauli are much shorter than in Campanulina A.
and strongly ringed throughout their length. The hydrothece are 0°25 mm. in
length by 0°15 mm. in diameter and apparently not so flexible as in A.

Their margins are cleft to form about the same number of opercular flaps.

There are about fifteen tentacles, 0°08 mm. in length.

Gonosome.—Unknown.

1. Agassiz, L.—Contr. Nat. Hist. U.S., iv., Boston (1862).
2. Auman, G. J—Monograph of Gymnoblastic Hydroids, pt. ii. (1872).
3. Amman, G. J.—Hydroida ‘ Challenger’ Reports, xxiii. (1888).
4. Bane, W. M.—Catalogue of Australian Hydroid Zoophytes (1884).
5. Bonnevin, K.—Zeitschr. wiss. Zool., Ixiii. (1898).
6. Bonnevre, K.—Hydroida, Norske Nordhavs-Expedition, xxvi. (1899).
7. Bonnevie, K.—Bergens Mus. Aarbog, No. 5, 1898, Bergen (1899).
8. Crark.—Trans. Conn. Acad. iii. (1876).
9. Hartiaus, C.—Hydroiden, Voyage du ‘ Belgica’ (1904).
10. Harriaus, C.—Zool. Jahrb. Supplement-Bd., vi. (1905).
44. Hurvcoxs, T.—British Hydroid Zoophytes (1868).
12. Hopasoy, T. V.—Preliminary Report of the Biological Collections of the ‘Discovery,’ Geographical
Journal, April, 1905.
13. JApERHOLM, E.—Arch. Zool. Exper. (4) III. (1904), pp. ixiv.
14. Liynarus, C.—Syst. Nat. x. (1758).
15. Marx, EH. L.—Bull. Mus. Comp. Zool., xxxii., No. 8 (1898).
16. Marx, E. L.—Zool. Anz. Bd. xxii., No. 590 (1899).
17. Morz-Kossowska, 8.—Avrch. Zool. Exper. Ser. 4, iii. (1905).
18. Nurrine, C. C.—American Hydroids, pt. 1 (1900).
19, Nurrine, C. C.—American Hydroids, pt. 2 (1904).
20. Nurrine, C. C.—U.S. Fish Commission Bull., xxiii., pt. 3, Washington (1905).
21. Sars, M.—Fauna Littoralis Norvegice, pt. 3 (1877).
22. Spencer, W. B.—Trans. Roy. Soc. Victoria (1890).
23. SweNANDER, (.—Kongl. Norske. Vid. Selsk. Skr., 1903, No. 6, Trondhjem (1904).
24. Torrey, H. B.—University of California Pub., i. (1902).

HYDROID ZOOPHYTES. 33

DESCRIPTION OF THE PLATES.

KEY TO THE LETTERING OF THE PLATES.

ac., acrocyst ; b/., blastostyle ; ¢.p., chitinous pellicle ; d., dactylozooid ; yph., gonophore ; y/h., gonotheca ;
gz., gastrozooid; fw., hydrocaulus; Arh., hydrorhiza; hth., lydrotheca; hyd., hydranth ;
m., manubrium; ”., node; nph., nematophore; op., operculum; ov., ovum; /p., perisarc ;
rhe., rhizocaulus ; sp., Sperm ; sv.c., sub-umbrella cavity ; ¢., tentacle ; v., umbrella; 2., zooid.

PLATE I.

Fig. 1.—Perigonimus antarcticus growing on Halecium arboreum (x 2). he. H., hydrocaulus of
Halecium arboreum; hyd., hydranth of Perigonimus ; gph., gonophore of Perigonimus.

Fie. 2.—Perigonimus antarcticus 6 (X 20). hrh., hydrorhiza; m., manubrium of gonophore ;
p., perisare ; sp., sperm filling the sub-umbrella cavity ; v., umbrella wall.

Fic. 3.—Perigonimus antarcticus 9 showing variability (due to contraction) of form of the hydranths
(x 20). he., hydrocaulus; hrh., hydrorhiza; hyd. hydranth; m., manubrium of gonophore ;
ov., ova embedded in the ectoderm of the manubrium ; sv.c., sub-umbrella cavity ; v., umbrella wall.

Fig. 4.—Eudendrium insigne. Hydranth (x 30). ¢., collar of deeply staining cells ; y., perisare.

Fig. 5.—Stylactis haleciti (x 30). Outer region of colony growing on Halecium arboreum; d., dacty-
lozooid ; he. H., hydrocaulus of Halectum; hrh., hydrovhiza ; gz., gastrozooid.

Fic. 6.—Stylactis halecii (x 20). Central region of colony growing on Halecium arboreum ; b1., blasto-
style ; d1.f., tentaculate blastostyle ; yz., gastrozooid ; ie. H., hydrocaulus of Halecium ; hrh. P. & C.
hydrorhize of Perigonimus and Campanularia.

PLATE II.

Fie. 7.—Hydractinia dendritica encrusting Halecium arboreum (x 10). 1., blastostyle ; gph., gonophore ;
g2., gastrozooid ; 7.sp., ridge-like spine.

Fic. 8.—Hydractinia dendritica. Fragment of rhizocaulus (x 20). 0/., blastostyles ; gph., gonophore ;
gz., gastrozooid ; rhe., rhizocaulus.

Fig. 9.—Hydractinia dendritica (x 2). Young rhizocauline colony developing from the encrusting
basal region ; enc. 7., encrusting region ; fr. riv., free rhizocauli.

Fig. 94.—Hydractinia dendritica, encrusting Halecium arboreum (x 1).

Fig. 10.—Hydractinia dendritica. Part of adult rhizocauline colony (x 1). r/ec., rhizocaulus ; 2., zooids.

Fia. 11.—Tubularia longstaffi (<x 1). gph., gonophores ; frh., hydrorhiza.

Fie. 12.—Tubularia ralphi (x 2).

Fie. 13.—Tubularia hodgsoni (x 1).

Fig. 14.—Lampra microrhiza (x 1). c¢.p., chitinous pellicle ; gph., gonophores ; hrh. f., hydrorhizal
filaments.

PLATE III.

Fre. 15.—Lampra parvula. Young zooid (x 10). d.t., distal tentacles; /e., hydrocaulus; hrh. f,
hyrdrorhizal filament ; iyd., hydranth ; p.t., proximal tentacles ; /.2., polyzoan colony to which the
zooid is attached.

VOL. Ul. DG

Fig.

Fic.

Fia.

Fig.

Fic.

Dice

Fie.
Fig.

Fig.

Fia.

Fia.

Fia.

SYDNEY J. HICKSON anp F. H. GRAVELY.

. 16.—Lampra parvula. Adult and smaller zooids (xX 1). ¢.p., chitinous pellicle ; f.sp., feltwork

of sponge-spicules and diatoms in which the basal ends of the zooids are embedded ; yph., gonophores.

. 17.—Corynidae, sp. B. (X 10). he., hydrocaulus ; Arh. f., hydrorhizal filaments ; iyd., hydranth.

18.—Myriothela ? (x 2). hrh. f., hydrorhizal filaments ; ¢., tentacles.

. 19.—Sertularella spiralis. Part of a pinnule (x 25). ac., acrocyst ; ect., ectodermal sheath around

base of hydranth ; gt/., gonotheca ; op., opercular flaps.

. 20.—Sertularella spiralis (x 25). Part of main axis, showing method of branching ; br., branch ;

hth., hydrotheca ; m.d., main axis.

. 21.—Sertularella plectilis (x 15). gth., young gonotheca; hyd., hydranth ; 7. hth., reduplicated

hydrotheca ; s. /th., simple hydrotheca.

. 22.—Dictyocladium fuscum (x 10). hth., hydrotheca ; s¢., stolon helping to bind the colony together

by anastomosing with another branch.

. 23.—Plumularia glacialis 9. Central axis and proximal part of hydrocladia (x 20). 9 gth.,

female gonotheca; /’h., hydrothecae ; nph., nematophores ; f. /cl., hydrocladia-bearing tube of
central axis ; ¢. sp., supporting tubes.

24.—-Plumularia glacialis 6. Part of a hydrocladium (x 40). 4 gih., male gonotheca; /yd.,
hydranth ; 7. Ael., node of hydrocladium ; nph., nematophore ; sp., sperm.

PLATE IY.

25.—Campanularia verticillata, var. grandis (x 2). he., hydrocaulus; hrh., hydrorhiza ; Ayd.,
hydranth ; s., sponge growing upon the hydrocaulus.

26.—Campanularia laevis (x 7). gth., gonotheca; de., hydrocaulus; frh., hydrorhiza; hyd.,
hydranth.

27.— Halecium arboreum; part of a hydrocladium (x 20). d., dactylozooid; hyd., hydranth ;
n., node; mph., nematophore; p., perisarc. (The measurements given in the text are of some
particularly well-expanded nematophores that we discovered after this figure was drawn.)

28.—Halecium arboreum. ‘Coppinia” mass (x 1). cp.m., “ coppinia” mass ; /.c., hydrocaulus.

29.—Halecium arboreum. Part of “coppinia” mass (x 15). d., dactylozooid ; gih., gonotheca ;
nph., nematophore.

30.—Obelia geniculata (x 3). To show mode of branching.

31.—Lafoéina longitheca (x 50). d., dactylozooid; Ayd., hydranth; op., opercular flaps ;
p., pevisare of hydrorhiza.

32.—Diagrammatie longitudinal section of a male gonophore of Perigonimus antarcticus (xX 50),
ecl., outer and inner ectoderm of umbrella in contact; ecf. wv. 7, inner ectoderm of umbrella ;
ect. U. 0., outer ectoderm of umbrella ; end. m., endoderm of manubrium ; end. 7. ¢., endoderm rod
representing the ring-canal; ms. m., mesogloea of manubrium; ms. /., mesogloeal lamella of
umbrella ; sp., sperm maturing from within outwards, and completely filling the subumbrella cavity ;
jt is omitted in the figure at sw. c., to give greater clearness to the different parts of the gonophore.

33.—Diagrammatic longitudinal section of male blastostyle of Stylactis halecii (X 50). c.y., collar
of perisarc around base of zooid ; ms., mesoglea ; n¢., nematocyst in the ectoderm; ¢., tentacle
(entirely ectodermal) ; other letters as in fig. 32.

34.—Diagrammatic longitudinal section of male gonophore of Tubularia hodysoni (xX 50).
Letters as in figs. 82 and 383.

35.—Diagrammatic longitudinal section of female gonophore of Lampra parvula (x 30). end. u.,
endoderm of umbrella ; ov., ovum lying amongst the other rounded and deeply staining cells of the
endocodon ; ov. rup., ovum rupturing the “umbrella” and protruding part of its substance through
to the exterior ; other letters as in figs. 32 and 33.

Antarctic (Discovery) Exp Plate I

. PERIGONIMUS ANTARCTICUS (1-3), EUDENDRIUM INSIGNE (4)

STYLACTIS HALECII (5,6)
| *

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Antarctic (Discovery) Exp. Dy

HYDRACTINIA DENDRITICA (7-10), TUBULARIA LONGSTAFFI (11),
T. RALPHII (12), T. HODGSONI (18), LAMPRA MICRORHIZA (14).

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PE—THNTACLES OF A SIPHONOPHORE.

Amone the specimens to which Mr. Hodgson, on his return from the Antarctic,
directed our attention, was an attenuated object which was the subject of a good
deal of speculation. Almost simultaneously with the discovery of its hydrozoic
nature, I received a copy of an interesting article by Dr. John Rennie, of Aberdeen,*
which settled the question. I print Mr. Hodgson’s account of his experiences, as it
displays most graphically the difficulties of collecting in glacial temperatures.
Dr. Rennie has been so kind as to examine the specimens, and has favoured me with
the following note and sketches.—F, J. B.

THE “ BOOTLACE.”

On July Ist, 1902, Lieut. M. Barne, R.N., returning from an excursion sounding
through holes in the ice of McMurdo Bay, brought me a specimen of what he
termed a “ Nemertine,’ from its superficial resemblance to some more bulky and
undoubted nemertines that were constantly being captured. This particular specimen
was taken on the sounding-wire some 80 fathoms from the bottom, the total
depth of water being 163 fathoms. It was only liberated with considerable difticulty,
and arrived on board in an imperfect condition, and, of course, frozen hard. It was
about as stout as an ordinary bootlace, somewhat ragged, and of a light brown colour.
I judged it to be very nearly twenty feet in leneth. It so happened that there was
no preservative material available at the time, and as sea-water could not be
‘obtained under half an hour, the heat of the ward-room caused the specimen to
disintegrate rapidly, and it was lost.

On August Ist, 1902, a stationary trap was hauled at No. 5 hole in 178 fathoms,
at a distance of a mile and a half from the ship. On the swabs attached thereto
the fibres

were two specimens of this organism. They lay as tangled masses among
of the swabs, and appeared to be about the same size, or larger, than the original

specimen, but stouter and evenly cylindrical throughout. Owing to the hole being
choked with ice crystals, no water could be obtained ; all specimens had to be brought
to the ship “dry.” The temperature at this time was — 50° Fahr., and under these
conditions the specimens were lost.
On December Ist, 1902, at No. 4 hole, the total depth of water being 41 fathoms,
a tow-net had been let down to a depth of 8 fathoms. On the line immediately above
the tow-net one of these organisms was entangled. As the weather was warm, little
* Scotia Collections.—On the Tentacles of an Antarctic Siphonophore. By John Rennie, D.Sc., University

of Aberdeen.

2D,

2 JOHN RENNIE, D.Sc.

a

below freezing point, and the water clear, it could be roughly examined before removal.
The organism appeared to be an inert and delicate structure, about a quarter of an
inch in diameter, which appeared to be uniform throughout its entire length, rounded
at both ends, translucent and light brown in colour for the most part, though im
places almost colourless. This specimen was secured, but in fragments, preserved in
picrie acid, and transferred to alcohol. Unfortunately the bottle in which it was
kept was one of the only two which failed, and some months later was found to be

7. 5a) J 5b)

JRitchie del. ButterWorTife
EXPLANATION OF FIGURES.

1, Piece of Tentacle, (Natural size.)
2: 5 , enlarged, showing Stinging Areas. x 18.
3. Transverse section: (a) Ectodermal Canal; (b) Endodermal Canal. x 40.
4, Stinging Areas, showing Cnidoblasts. x 280.
5. (a) Cnidoblast, with coiled lasso.
(bd) y , With lasso shot out. x 500.

practically dry ; the specimen was then replaced in alcohol and kept under observation.
No other specimen was taken, but from the date of its first capture on Lieut. Barne’s
sounding-line to the close of our stay in McMurdo Bay it occurred on the
lines of the nets and traps frequently, probably not less than fifty times. It was
usually much attenuated by being drawn somewhat rapidly through the water, and
shredded on the iron bar over which the line ran. This last piece of apparatus was an
essential, as the line has to be laid straight out on the ice. A wet line at those
temperatures can neither be coiled nor wound on a winch. The organism usually

TENTACLES OF A SIPHONOPHORE. 3

occupied from ten to twenty fathoms of line as it was drawn up. No time of the year
can be definitely stated as to when it was most abundant.

Note by Joun Rennig, D.Se., University of Aberdeen.

The specimens described as “ bootlaces” consist of a number of tentacles of a
Siphonophore, taken by Mr. Hodgson under the difficulties just described. The state
of preservation is not very good, the parts are extremely friable, and break readily
on manipulation. It is not possible to tell whether they originally formed one piece*
or not. Besides smaller portions, there are nine parts, ranging in length from
about 30 cm. to 6 cm., with an almost uniform diameter of 3°6 mm. The surface
is in colour a dirty greyish white, and under a low power is seen to be divided up
into definitely marked areas (see figs. 1-5), such as distinguish the tentacles found by
the Scottish Antarctic Expedition, and described by me.t Cnidoblasts of large size are
present in great abundance upon these areas. They possess a lasso, which is at least
nine times the length of the cell, and which is barbed throughout its entire leneth.
Ketodermal and endodermal canals of the ordinary type are present, and no further
noteworthy features are observable. These tentacles differ from those of the Scottish
Expedition, both in colour and consistency, the latter beg brownish and of a markedly
gelatinous nature even in their badly preserved parts. They appear to belong to a
distinct and otherwise unknown form.

* Before being taken from the water the organism was unquestionably in a single piece, and was so whenever

it occurred.—T.V.H.
t Proc. Royal Physical Society, Edin. XVI. (1904), p. 25-7.

PORIFERA.

By R. Kirkpatrick.

THE Sponges brought home by the ‘Discovery’ from the Antarctic Region were
obtained mostly from two localities, viz., from 183 métres (100 fathoms) off Coulman
Island, about 200 miles north of the Winter Quarters, and from the neighbourhood
of the Winter Quarters (Lat. 77° 49'S., Long. 167° 7’ 4” E.), from depths ranging
from 9m. to 366 m. (5-200 fms.); one specimen, a new species of Hexactinellida,
came from 914 m. (500 fms.) off Mount Erebus, and another, also a new species
of the same group, was dredged from 464 m. (254 fms.) when the ship was
crossing the Antarctic Circle, on the voyage home; and, lastly, a few Sponges were
dredged near the edge of the great Ice Barrier, some degrees eastward of Winter
Quarters.

The specimens were procured by means of dredges of various kinds, such as trawls
and D-nets, sometimes with tangles attached. Wherever possible, the apparatus was
lowered in open water, but after the ship was frozen in, holes were made in the ice ;
and it was necessary to adopt elaboraté precautions to prevent the dredges being lost
and to enable them to be dragged along the bottom. By these means there were
obtained a large number of specimens, which afford testimony to the indefatigable
industry and resourcefulness of Mr. T. V. Hodgson, who was in charge of the dredging
operations. .

Mr. Hodgson, in his Preliminary Report on the biological collections (3, p. 397),
observes, ‘‘ A predominant feature in the fauna was the enormous quantity of sponges
and sponge débris, anywhere near the 20-fathom line spon
forming the bulk of the haul as a rule.”

ges and sponge débris

The bulk of the collection so far as concerns the size and number of specimens is
made up mainly of Tetractinellida and Hexactinellida. There are fifty-nine specimens
of Tetractinellid Sponges, some of them of large size, belonging to four species; the

5

‘Belgica’ Antarctic Expedition dredging in the neighbourhood of the meridian of
90° W. found none belonging to this group. The Monaxonellida are represented by
forty-three species, and the Calearea by twenty-four species. There are no Keratosa or
Horny Sponges.

With the exception of two dried specimens and of a few in formalin, the
collection is preserved in strong spirit.

bo

R. KIRKPATRICK.

I.—-HEXACTINELUIDA.
(7 Plates.)

Tue Hexactinellid Sponges, comprising thirty-four specimens and sixteen macerated
fracments, all belong to one Family, the J?ossellide. The specimens represent five
genera, of which three are new, and ten species, of which eight have not been described
before. The following is a list of species with depths and localities :—

FAMILY ROSSELLID, F. E. Scuvuze.
(Sus-Famity RosseLiin#, F. E. Schulze.)
Hyalascus hodgsoni. Off Mount Terror, 914 metres (500 fathoms).
Rossella antarctica Carter. W.Q., 238 m. (130 fms.).
Rossella podagrosa, W.Q., 18-55 m. (10-30 fms.).
Rossella racovitze Topsent. W.Q., 18-86 m. (10-20 fms.).
Rossella heaactinophila. Antarctic Circle, Long. 155° 21' H., 464 m. (254 fms.).
6. Aulorossella pilosa. Off Coulman Island, 183 m. (100 fms.).
7. Aulorossella levis. W.Q., 18-325 m. (10-178 fms.).
8. Aulorossella longstafi. W.Q., 238 m. (130 fms.).
9. Anaulosoma schulzii. W.Q., 36-75 m., (20-41 fms.).

om oF to Fe

Sup-Famity LANUGINELLINe, F. E. Schulze.
10. Anorycalyx timai. W.Q., 329 m. (180 fms.).

Two species in the above list have been described before: one of these, Rossella
antarctica Carter (2, p. 114), was dredged by Sir James Clark Ross in Lat. 74° 30'S.
Long. 75° E., 549 m. (300 fms.), during the voyage of discovery to the Antarctic
Regions in 1839-43; the other, Rossella racovitze Topsent (11, p. 33), was obtained in
1897-99 by the ‘ Belgica’ from Lat. 70°-71° 8. Long. 80°-87° W., 450-569 m.
(267-310 fms.).

To the one species previously known from the Antarctic, the ‘ Belgica,’ dredging
in Lat. 70°-71° 8., Long. 80°-89° W., added the following nine :—

? Caulophacus sp. 450 m. (246 fms.).
Rossella nuda Topsent. 430 m. (235 fms.).
. Rossella racovitze Topsent. 450-569 m. (246-811 fms.).

Bathydorus spinosus F, EB. Schulze. 569 m. (311 fms.); also from Penguin Island, 2926 m.
(1600 fms.) [‘ Challenger ’).

H= oo bo et

5. Rhabdocalyptus australis Topsent. 450 m.

6. Farrea occa (Bowerbank) Carter. 450 m.

7. Eurete gerlachei Topsent. 450-550 m. (246-301 fms.).
8. Chonelasma sp. 450-500 m. (246-273 fms.).

9. Uncinatera plicata Topsent. 430-500 m. (235-273 fms.).

All of the eighteen Antarctic species belong to the Hexasterophora, not one
representative of the Amphidiscophora having been found hitherto.

In connection with bathymetrical distribution it is interesting to note that
specimens of four of the species obtained by the ‘ Discovery ’ come from comparatively
shallow water, from depths ranging from 18-75 m. (10-41 fms.).

HEXACTINELLIDA. 3

A curious phenomenon remains to be noticed. On October 24th, 1903, Lieutenant
Armitage’s sledge party found a dried macerated Hexactinellid Sponge and also tufts of
spicules being ‘“‘blown about by the wind amongst the erratics on the ice.” The
existence of recent Hexactinellid Sponges on the surface of the earth and brought there
by natural agencies is a very unusual occurrence ; for, generally, these Sponges live in
too deep water to be cast up by storms. In the present instance, probably the sea
bottom was scooped up by ice, and the material afterwards floated up on detached
masses of ice. Both the specimen and tufts of spicules belong to a new species, viz.,
Aulorossella levis, common in shallow water up to 20 fathoms.

ABBREVIATIONS AND EXPLANATIONS.

(1) W.Q. means “ Winter Quarters.”

(2) A Roman and an Arabic numeral in brackets mean number of plate and
figure ; thus (I. 6) means Plate L, fig. 6.

ORDER HEXACTINELLIDA, F. E. Scuvutze.

Sup-orpER HexastreropHora, F. E. Schulze.
Famity Rossevitipa, F. E. Schulze.
Sup-FAMILY RossELtin.z, F. E. Schulze.
Hyaxascus, Tjima.

HYALAscus HODGSONI,
(Plate III. fig. 1, and Plate IV. figs. 1 a-g.)

Sponge an elongated, slightly flattened oval sac, broadest a little above the base,
with an oval orifice with thin, soft, felt-like, unarmed edge.

Surface with a few small, pointed, tuft-like conuli; with oxydiactin, and rarely
oxypentactin pleuralia. With rounded base provided with short scattered bundles of
basalia (probably forming a root-tuft in complete specimens). Gastral membrane
continuous (to the naked eye). Autodermalia hexactins, rarely pentactins ; hypodermalia
oxypentactins with smooth surface. Gastralia slender hexactins. Intermedia
holoxyhexasters,* hemioxyhexasters, rarely monoxyhexasters * ; discohexasters, and
microdiscohexasters. Colour (in spirit), pale buff; consistence rather soft and flexible,
but firm enough for the walls to be self-supporting when out of spirit.

Description of the specimen. The single specimen representing the new species
appears to be in an incomplete state, and has probably been denuded of many pleuralia,

* The term monoxyhexaster is used for oxyhexasters in which all the secondary or terminal rays are single,
hemioxyhexasters (Ijima) being oxyhexasters in which only one, or some, but not all, of the terminal rays
are single, and holoxyhexasters oxyhexasters with all the primary rays ending in more than one terminal ray ;
similarly, the terms holodiscohexaster, hemidiscohexaster (Schulze), and monodiscohexaster explain themselves.
Prof. Tjima’s view (4, p. 118, footnote) that the first kind of spicules, viz., monoxyhexasters, should be designated
“‘hexasters” and not “hexactins” (Schulze, 9, pp. 8-11) seems to me justifiable. irstly, the axial canals are
confined to the basal portion of each ray (primary ray) and do not extend to the terminal portion (secondary Tay).
I have examined numerous monoxyhexasters and some monodiscohexasters, and by using a 12-inch oil immersion

and by adjusting the light, I have invariably found that the axial canal comes to an abrupt end not far from the

»)
VOL, III. 2H

4 R. KIRKPATRICK.

and possibly also of a root-tuft. A few external (? velar) hypodermal oxypentactins are
present on the surface, and little tufts of broken-off basalia project from the rounded
base of the specimen. There may be a well developed root-tuft in complete specimens ;
further doubts on this point were suggested by the condition of four specimens of a
species of Craniella from the Antarctic, three being almost smooth at the lower end, owing
to the root-tuft having been detached in dredging, whereas the fourth has a large root-tuft.

The dimensions of the specimen are as follows :—Height, 14cm. ; greatest breadth,
Gem. ; diameter of orifice, which is slightly torn, about 4em.; greatest thickness of
wall, 1°1cem.

The lumen of the deep gastral cavity is occupied by numerous scattered internally
projecting pleuralia, which have been driven in from the outside. The circular
openings of the ostia, about 1*5mm. in diameter, are clearly visible beneath the dermal
layer ; also the slightly larger postica are perceptible beneath the gastral layer, which
roofs them over with a fine lace-like reticulum.

Skeleton. The skeletal framework is formed of bundles of diactins ; there are
no large hexactins.

Spicules. ‘The principalia are oxydiactins, about 7000 x 80p in size, with fine
tapering ends smooth or only very slightly spimed. A much smaller kind, 1400 x 18p,
separate, and not in bundles, with roughened ends and four central knobs, is common
beneath the dermal and gastral membranes.

The autodermalia (IV. 1a) are spined hexactins, each ray being 131 in length
and 15°54 broad at the base, slightly tapering to a blunt extremity; pentactins
(LY. 1b), with the odd ray proximal, occur, but very rarely.

The hypodermalia (IV. 1d, d’) are oxypentactins with slender ameoth tapering
paratangentials, each about 2700 x 40m, the rays being either orthotropal or
anorthotropal.

The autogastralia (IV.1d°) are spined hexactins with slightly longer and more
slender and sharply pointed rays than the autodermalia, each ray being 1836 x 7° 5p.

The intermedia, Holoxyhexasters* (IV. le) and hemioxyhexasters (IV. le’),
varying in diameter from 100 to 120m, are common. Monoxyhexasters* (IV. le’), 108u
in diameter, occur only rarely. Medium-sized holodiscohexasters (IV. 1f, f*), from
80-100 in diameter, are also rare ; the short slender primary rays, about 7p in length,

base of the ray, and that the remaining portion of the ray is devoid of any trace of an axial canal, that it is,
in fact, more of the nature of a spine. Secondly, in many instances, all the transitions can be traced from
holohexasters, through several grades of hemihexasters to monohexasters. In a preparation of Rossella racovitze
Topsent, for example, these transitions can be traced in a crowd of discohexasters, the monodiscohexasters having
short thick primary rays with the axial canal extending only to the point where the thick portion (primary ray)
joins the more slender solid terminal portion. To call such spicules as these last disecohexactins would be to
lose sight of the fact that they clearly have six primary and six single secondary rays, for the latter do not lose
the character of being secondary simply because they are single. A genuine hexactin would, by its definition,
have no secondary rays. The designation ‘ hexactinose,’ used by Ijima, would, perhaps, be better written
‘“‘hexactinoid,” or hexactin-like, but even this term is not without objection, since such a spicule with its primary
and secondary rays is seen, under a high power, not to resemble a true hexactin. Accordingly the prefixes
“holo-,”’ “ hemi-,” and “mono-,” added to ‘“oxy-” or ‘“disco-’’ hexaster, are suggested as indicating and
defining the form and relationship of these spicules. The following figures show the limitation of the axial

HEXACTINELLIDA. 5

divide into two or three terminals tipped with toothed discs. Microdiscohexasters
(IV. 1g), 43 in diameter, have slender primary rays, each 6° 5y in length, ending in a
plano-convex capitulum,f from the distal convex surface of which are given off disc-
tipped terminal rays of two lengths.

This species is placed under Hyalascus on account of the absence of calycocomes,
this negative character being the chief one which separates the genus from /tossella.

The three other known species of //yalascus (5, p. 87), viz., [/. sagamiensis 1j., HT
similis 1j., and H. giganteus Ij., are Japanese. They are all vase- or sack-shaped; the
first-named species is vase-shaped, has an orifice with everted lips, and is much
contracted below ; the second, which Ijima regards as possibly identical with the first,
has a basal stalk ; the third is in the form of a large flattened sac with a plain orifice.
In all the Japanese species the autodermalia are mainly pentactins, but in the
Antarctic species these spicules are mainly hexactins, pentactins being very rare.

Near the lower end of the sponge is a small conical elevation about 1°3 em. in
height, with a central axis of diactins. The autodermalia have here undergone a
remarkable change (IV. 1c-c’); they have become more or less fused together, and
have lost one or more of their rays, while the spines resemble the flat articular surfaces
and tubercles on the desmas of Lithistid Sponges. All the stages of transition can be
traced from a slightly modified pentactin to a long desma-like form, such as that figured
in Plate IV., fig. 1c. Probably these changes have resulted from irritation set up by
contact with some foreign body, just as basidictyonalia form at the point of attachment
of many of the Hexactinellida. On another part of the dermal surface is a small round
patch, 1°5 cm. in diameter, lighter in colour than the rest of the surface, occupied by
small densely crowded autodermalia. Ijima (5, p. 90) refers to similar patches on the
gastral surface of HH. sagamiensis, “‘ due to excessive local accumulations of gastralia.”

Dredged from 914 métres (500 fathoms) off Mount Erebus.

RossELLA ANTARCTICA.
(Plate I., figs. 1 to 4, and Plate IV., figs. 2a to g, and 3a to k.)

1872 Rossella antarctica, Carter (1, p. 409, pl. xxi.).
1875 > en Cas Demy ple xe, tig 4) 5
1887 3 F. E. Schulze (6, p. 139, pl. lv.).

Three specimens of this species were obtained. They were brought up in the
same haul from Winter Quarters, No. 10 hole, 130 fms. The specimens show a

canals to the primary rays, and the spine-like nature of the secondary rays:—Pl. IV., fig. 2d*° shows an
hexactin-like monoxyhexaster with the axial canals extending but a very short distance from the centre, the rest
of each ray being solid. Pl. VIL., fig. Lh, shows a monodiscohexaster with the axial canals extending only to the
end of the basal thick portion of each ray. PI. IV., fig. 8d° shows three spheroidal reduced hexasters in which
the primary rays have disappeared as rays, while the secondary rays remain as one or more spines, or even
spheres, attached to the central sphere, the axial canals being confined to the central node or sphere. Pl. IV.,
fig. 3d‘ (on the left edge of the plate) shows a monoxyhexaster in which one of the six secondary rays is becoming
reduced, this being a stage on the way to becoming a spheroidal reduced hexaster.

+ The descriptive term “ capitulum” is suggested for the enlargement or swelling at the distal end of the
primary rays of calycocomes, aspidoplumicomes, strobilocomes, microdiscohexasters, etc. The shape of the
“ capitulum ” in these spicules calls to mind the receptaculum and capitulum of the Compositie.

2H 2

6 R. KIRKPATRICK.

considerable amount of variation, and will be described separately as A, B, and C.
Had they not come from the same spot, I would probably have regarded B and C as
representing a variety of the typical form. All the specimens possess a well-developed
root-tuft, therein differing from those obtained from Kerguelen and other localities in
the Southern Indian Ocean, and from near the mouth of the Rio de la Plata in the
South Atlantic. Prof. Schulze mentions in the ‘ Challenger’ Report (p. 139) that he
had never found the loose root-tuft, which Carter represents in his diagrammatic figure
(2, pl. x., fig. 4), and he considers this modification in the original specimen to
be conditioned by the looser nature of the substratum.

Prof. Ijima observes (5, p. 5) that “a case of one and the same Hexactinellid
species being firmly fixed when growing on a hard substratum, but producing a root-tuft
when living on a soft bottom, has never as yet been shown to exist.” The ‘ Discovery ’
and ‘Challenger’ specimens of /ossella antarctica seem to me to furnish instances of
specimens of the same species being fixed solidly or by a root-tuft in accordance with
the nature of the bottom. In spite of the considerable range of variation in bodily
form, mode of fixation and spiculation, the Antarctic and the more northerly forms
appear to me to come within the limits of one and the same species, but I regard the
latter as belonging to a variety—var. solida. The microdiscohexasters, too, are
considerably larger in the typical Antarctic specimens than in the northern variety.
If the anchor spicule figured by Schulze (6, pl. lv., fig. 12) really belongs to the
specimen from which it was obtained, its presence suggests that the sponge, now solidly
fixed without a root-tuft, was derived from a form with such an appendage.

Specimen A.—(Plate I, fig. 1, and Plate IV., fig. 2 a—g.)

This, which is the smallest of the three specimens, closely resembles the original
one obtained by Sir James Ross and diagrammatically figured by Carter (2, pl. x.,
fic. 4). The tatal length is 7 em., the body being 4 em., the root-tuft 2 cm., and
the oral fringe nearly 1 cm. in length. The greatest breadth is 3em. The velum
is about 7 mm. from the surface of the body. Numerous oval or pyriform buds, each
about 2 mm. in length, are present amidst the dense tangle of the velum. The orifice
is narrow, oval, about 1 em. in length, and acute-angled at each end. ‘The diactin
marginalia surrounding it form a sloping palisade which meets in the middle line
above, the inclination increasing from without inwards. The root-tuft, which encloses
débris of worm-tubes, fragments of Polyzoa, etc., is formed of pentactins in the shape
of four-pronged anchors with thick curved prongs. The surface of the body is level,
though here and there small, barely perceptible conuli occur. The skeleton is mainly
formed of long wavy bundles of slender diactins.

Spicules.—The principalia are long slender diactins, often with roughened,
rounded or bulbous ends. There are also parenchymal regular hexactins (IV., 2a)
scattered about. The marginalia are sharp-pointed oxydiactins 1°5 em. long and
160» thick. The basalia are long, slender, four-pronged anchors 4 em. in length, with

HEXACTINELLIDA. 7

curved prongs 459 » in length. The autodermalia (IV., 2 b-b’) are hexactins (2b’),
pentactins (2b), and rarely stauractins (2b’), each ray being 75 x 11 p, wholly spined,
nearly cylindrical, and with blunt end. The pentactins have a well-developed distal
spiny knob. The hypodermalia are slender oxypentactins with paratangential rays
with roughened surface and with large prickles. These well-known spicules are not
figured owing to want of space. The autogastralia (IV., 2c) are large slender
hexactins, each ray being 173 x 6p. Some of the hexactins, a little below the
surface, are very large, with the radial rays (each 252 x 21 yu) longer than the
other four. The intermedia.—The holoxyhexasters (IV., 2d, d'), hemioxyhexasters
(IV., 2d°), and monoxyhexasters (IV., 2d®, 2d‘), about 164 in diameter, have very
slender roughened rays, the primary rays being very short or almost absent. The
calycocomes (IV., 2f) are 80 » in diameter, with long tuberculated primary rays, each
22 mw in length, ending in a solid hemispherical capitulum from which the only slightly
divergent secondary rays proceed, presenting, as Carter put it, a dinner-fork-like aspect
in optical section. Another kind of calycocome (IV., 22) has shorter, thicker, and
smoother primary rays, a knob-like capitulum, and more divergent secondary rays.
Medium-sized holodiscohexasters, like those figured by Schulze (6, pl. lv., fig. 15) do
oceur, but rarely. Plate IV., Fig. 2e, shows a modified hemidiscohexaster 45°5 mw in
diameter, having bulbous primary rays, and terminal discs little more than a circle of
spines. The microdiscohexasters (IV., 2h), 50 » in diameter, have long primary rays
10 » in length, ending in a conical point, the secondary rays being given off in two
circles a little separated from each other.

Scattered over the outer surface of the upper part of the specimen are numerous
small flattened pyriform buds about 52 mm. in length, each bud being supported on
one or two pleuralia which penetrate it. None of the buds are sufficiently developed
to show oscule or central cavity. The hypodermal oxypentactins have their paratan-
gential rays much more curved than in the adult state, and the prickles are hardly at
all developed. The soft tissues appear much contracted by the strong spirit. A
section shows an outer trabecular layer surrounding a central mass of choanosome,
there being only a slight development of an inner trabecular layer, and that so
contracted as to appear solid rather than reticular.

Specimen B.—(Plate [., fig. 2, and pl. IV., fig. 53h.)

This is a large spheroidal sponge, 15°5 cm. in height, with a dense velum
resembling a tangled thicket, extending about 1*1 cm. away from the surface, and
with a thick root-tuft. The orifice, which is oval and with sharp angles at each end,
is 3°7 cm. in length by 1°4 em. in its greatest breadth.

The marginalia, projecting about 2 cm., lean towards each other across the orifice,
the innermost layer extending almost horizontally across from one side; on a level
with the oscule is a depression, looking like a second oscule, but the appearance is due

8 R. KIRKPATRICK.

to the presence of a worm-tube in the wall of the sponge, thereby leading to a dis-
arrangement of the pleuralia and velum.

The gastral cavity is capacious, and is lined by a continuous gastral membrane.
The wall of the sponge is about 2 cm. thick. The spicules, with certain exceptions,
resemble those of specimen € described below.

Specimen C.—(Plate I, figs. 3, 4 and pl. IV., figs. 3a-31, excepting 3h).

This is a remarkable twin specimen, ovate spheroidal in shape, and with two oscules.
The height is 14 em. and width 19 em. The massive, dense root-tuft is 5°5 em. in
length. The edges of the oscules are slightly inverted, so that the innermost margi-
nalia, projecting 2°5 cm., slope downwards and inwards. <A vertical section through
the line joining the oscules shows the sponge body, apart from the massive root-tuft,
to be somewhat hour-glass-shaped with the long axis horizontal.

The common gastral cavity is nearly divided into ‘two by a thick, central,
pyramidal boss reaching from floor to roof, but not forming a complete partition.

The wall of the sponge attains in one part the great thickness of 3°8 cm. The
gastral surface shows numerous circular orifices, from 1 to 3 mm. in diameter, in this
respect differing from other known specimens of this species, in all of which the
gastral surface is covered with a continuous layer.

The twin condition of the specimen cannot be regarded as one of any specific
importance. Among the specimens of 2. antarctica obtained by the ‘Challenger’
from 274 m. off Kerguelen Island is a twin specimen with a short common hase
whence spring two thick cylindrical tubes ; the shape somewhat resembles that of a
gigantic tuning-fork. The gastral cavities communicate through an oval foramen
below, and the gastral membrane is continuous throughout.

Spicules of Specimen C.—The principalia are diactins with rounded or
bulbous, roughened ends, and large regular hexactins with smooth tapering rays each
640u in length.

The marginalia are smooth, thick, fusiform diactins, about 4 cm. in length,
and 270 in thickness in the middle.

The basalia (IV. 3a, a') are anchor pentactins with four prongs, usually curved,
but sometimes straight. Both in B and € these anchor spicules are present among the
hypodermalia some distance above the root-tuft, and some have the prongs anortho-
tropal, thus supporting Schulze’s supposition that pentactin basalia are often modified
hypodermal pentactins.

The autodermalia (IV. 3b.) are chiefly pentactins with or without a distal knob ;
hexactins being fairly common in B, but rare in C.

The oxypentactin hypodermalia, as might be expected, are larger than in
specimen A, and have thicker rays with longer prickles.

The autogastralia (LV. 3c) are mainly hexactins with spined, blunt-ended rays,

HEXACTINELLIDA. 9

each 83 x I1p; in C autogastral pentactins (IV. 3c’) are, in addition to the hexactins,
quite common.

On re-examining the autogastral hexactins of A, B, C,I find the differences are not
so great as is depicted in IV. 2c and IV. 3c. The spicule shown in IV. 2¢ has excep-
tionally long and slender rays, and that shown in IV. 3c has exceptionally short and blunt
rays. Inspecimen B the rays (266 x 15,) are slender, sharp-pointed and slightly spined.

Intermedia. The holoxyhexasters, hemioxyhexasters and monoxyhexasters show
a considerable amount of variation and abnormality, especially in the twin specimen C.
The holoxyhexasters and hemioxyhexasters are on an average from 100 to 110p in
diameter; fig. 3d shows a small holoxyhexaster (in optical section) only 62m in
diameter. Usually the primary rays are small but distinct. The monoxyhexasters
(IV. 3d**), 126 in diameter, have sharp-pointed secondary rays with rough surface,
are broad at the base and tapering to a sharp point. The abnormal spicules figured in
fig. 3d° have the primary rays reduced to a central node or sphere, and the secondary

“rays to a few spines. In some hexasters (IV. 3e) the secondary rays terminate in two
or three sharp prickles.

3d° shows a stauractin-like monoxyhexaster, 145 in diameter, the rays having a
roughened surface. That these spicules are not young autodermal stauractins is shown
by the fact that the axial canals extend only a short distance from the centre.

The calycocomes (IV. 3f-h), 80 to 90 in diameter, show considerable variation,
not only in specimens B and C, but also in the same specimen, viz., variation in size, in
length and thickness of the primary rays, in the length and degree of divergence of the
secondary rays, and in the presence or absence of terminal disks. Fig. 3h, from
specimen B, is evidently abnormal ; here some of the secondary rays have fine bifid or
trifid terminations.

Hemidiscohexasters of medium size (IV. 3e, e'), average about 85y in diameter ;
the rays are sometimes thicker and straighter than is usual in this species.

Monodiscohexasters, 90” in diameter, occur rarely. Prof. Schulze figures
(6, pl. LV., fig. 8) a spicule of this kind—the only one found by him—from a
specimen from Kerguelen Island.

The microdiscohexasters (IV. 3k), 50 in diameter, are mostly similar to those in
specimen A, with a narrow conical capitulum, whence two circles of secondary rays
originate ; some, however, have a more disk-like capitulum (IV. 31); the secondary
rays in both kinds are extremely slender, being almost invisible under any object-glass
lower than 5 inch. Curiously enough, these rays are much more easily discernible in
the younger and less developed specimen A.

All from W.Q., June 3rd, 1903. No. 10 hole; 238 m. (130 fms).
Other specimens have been found at :—
Lat. 774° S., long. 175° W. ; 548 m. (300 fms.) ; Sir J. C. Ross’s Expedition.
Prince Edward Island, 256 m. (140 fms.) ; Voy. ‘ Challenger.’

x

R. KIRKPATRICHI

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‘MOTH GHLVTNAV [, WAV VOljIIDJUD VijaSsOEY AO SNUWIONdG SOOIUVA AHL dO SYALOVUVHY) AHL dO AWOS

Ra

HEXACTINELLIDA. 11

Possession Island, 384 m. (210 fms.) ; Voy. ‘ Challenger.’
Kerguelen Island, 274 m. (150 fms.) ; Voy. ‘ Challenger.’
East of Buenos Ayres, 1097 m. (600 fms.) ; Voy. ‘ Challenger.’

ROssELLA PODAGROSA.

(Plate III, figs. 2, 3, and Plate V., figs. la—m.)

Sponge cylindro-conic, broadest about the middle, with wide, oval, thin-edged
orifice, armed with upright marginalia ; the walls thick and firm, with a well-developed
root-tuft, composed of diactins and of oxypentactins of the same character as those of
the velum. With a velum about 5 em. from the surface ; with buds of considerable
size, solidly attached to the parent by a broad base. The hypodermalia oxypentactins
with rough or smooth rays, without prickles.

The calycocomes with relatively short primary rays; discohexasters with long
secondary rays.

There are ten specimens of this species, one of large size, four of medium size,
and five small ones, some of which are probably detached buds. All the larger and
three of the smallest specimens possess relatively large buds, with oscule and gastral
cavity, and fixed by a broad base; compared with these, the buds on one of the
specimens of f. antarctica (see page 7) are very small, being only 2 mm. in
diameter, and detached from the main body, though still adherent to the pleuralia.
The largest specimen (PI. III., fig. 2) is 20 cm. in length, and 8°5 cm. in greatest
breadth ; the orifice is 2°5 x 2 cm. in diameter; the walls attain a thickness of
2°5em. ‘Two buds and the scar of a third are present on the outer wall.

Beneath the fine, gauze-like dermal layer are seen the round openings of the
ostia from *5 to 2 mm. in diameter.

The diactin marginalia project about 1°8 cm. The root-tuft is about 3°5 cm.
in length. A few slender diactin pleuralia project a little above the general velar
surface. The gastral membrane, which forms a continuous, finely pilose layer, with a
sharply-defined circular rim a little below the edge of the orifice, roofs over the
openings of the postica with a fine, sieve-like network, the meshes of which are formed of
bundles of diactins covered with autogastral hexactins. In one specimen the lower part
of the gastral membrane is cavernous. In all but the smallest specimens the central
cavity is deep, but in the latter it only extends to half the length of the sponge body.

The skeleton is mainly formed of bundles of diactins with a few large hexactins.

The spieules. Principalia. The long diactins mostly smooth, or only very
faintly roughened near the ends, usually straight, tapering very gradually to slender,
sharp points, a large spicule being 8°25x°054 mm. Hexactins of two kinds, either
regular with thickly spined rays, each 380 x 10p (V. 1b), or with the rays nearly
smooth, and with the odd pair of rays (each 1500 x 45m) equal or unequal, and longer
than the other four (V. 1a).

VOL, III,

bo
=

12 R. KIRKPATRICK.

The autodermailia (V. 1c) are pentactins with or without a distal knob, with all the
rays (each 180 x 13 in length) tapering and wholly spined. Hexactins occur, but rarely.

The hypodermalia (V. 1d-d’) (pleuralia and basalia) are oxypentactins with
rough or smooth rays, orthotropal or anorthotropal, the average length of a
paratangential being 1660 x 50m.

The autogastralia (V. le) are hexactins 266 x 12, and closely spined.

The intermedia are holoxyhexasters (rare), hemioxyhexasters (V. lf, f*), and
abundant monoxyhexasters (V. 1f°, f°), about 1694 in diameter. The calycocomes
(V. 1g, g') are 226 in diameter. The primary rays are only 8 in length; the
capitulum is 14°5y in length and 22 in breadth; the secondary rays, 3 to 5 in
number, are thick, and either without any terminal knob, or with a very small one.

Fig. th, a calycocome, with long primary rays, and without terminal disks, is only
87p in diameter, and is probably immature.

The discohexasters (V. 1k) are of large size, averaging 110m in diameter; the
primary rays (each 4°5u in length) terminate in two to four long, disk-tipped
secondary rays.

Fig. 11 shows a monodiscohexaster 120 in diameter.

The microdiscohexasters (V. 1m) are 51 in diameter; the primary rays, each
7 in length, terminate in a convex disk-shaped capitulum, from the distal surface of
which rays two lengths are given off, the longer rays having larger disks.

Rossella podagrosa differs from R. antarctica in that the hypodermal oxypentactins
are without prickles; secondly, the basalia resemble the pleuralia, whereas in L.
antarctica the basalia are anchor-like ; further, the calyeocomes of the new species have
very short primary rays; and lastly, the buds are entirely different in the two species.

Rossella nuda Topsent, has no velum.

Rossella racovitze Topsent, is likewise without a velum, and its surface is covered
with conules.

Rossella henactinophila, a new species about to be described, closely resembles
ft. podagrosa, but is distinguished by its hexactin autodermalia, and by the different
shape and larger'size of the calycocomes ; also its oxyhexasters have more slender rays.

All specimens were obtained from Winter Quarters by means of the D-net. (1) No.
104, Hut Point, September 24, 1902, 26 m. (14 fathoms) ; (2) Nos. 118, 120, Hut Point,
November 13, 1902, 46m. (25 fathoms); (3) No. 137, Flagon Point, January 17, 1903,
18-36 m. (10-20 fathoms) ; (4) No. 139, January 23, 1908, 18-36 m.; (5) No. 239, 12
hole, 46-55 m. (25-80 fathoms).

AOSSELLA HEXACTINOPHILA.
(Plate HL, fig. 4, and Plate VI, figs. la—g.)
Sponge forming an elongated oval flattened sack with a sharp-edged oval orifice
provided with marginalia. With a velum; and with a root-tuft about 2 cm. in length
mainly composed of oxypentactins resembling those of the velum.

HEXACTINELLIDA. 13

Autodermalia hexactins; oxypentactine hypodermalia with rough or smooth
surface and without prickles ; oxyhexasters with extremely slender rays.

The single specimen representing the above species is in a bad state of preserva-
tion, the five half-macerated fragments of grayish colour being saturated with mud.
Mr. Hodgson gives the information that on the return voyage the trawl was put
overboard and dragged for some distance over a dead level bottom of mud, but that
at one spot the trawl passed over a patch of stones dropped by an iceberg. This
would account for the condition of the specimen. With some difficulty the fragments
were pieced together in the manner shown on PI. III., fig. 4; there was no doubt
about the base with its small but indubitable root-tuft, nor about the oscular end, but
possibly a fragment may be missing from the intervening part; enough remains,
however, to show that the sponge was narrow at the orifice and broader at the lower
end than above. The specimen, as made up, is 16 em. in length, and 5 cm. in breadth
below the middle. The orifice, which is 1°5 em. in diameter, is partly surrounded by
diactin marginalia projecting about 1°5 em. The root-tuft is formed of dense tufts of
basalia caked with mud at the ends. The velum has been mostly rubbed away ; but
patches of it exist, especially in the fragment bearing the oscule. The gastral
membrane is continuous.

Skeleton.—The framework is formed of bundles of thin slender diactins.

Spicules.—The principalia are diactins very long and slender, averaging
3500 x 1°*5u, mostly entirely smooth, and with sharp-pointed ends, though some are
slightly roughened at the ends.

The autodermalia (VI. 1a) are hexactins, with rather sharp-pointed rays each
154 x 12y, and spined throughout; the hexactins give a pilose appearance to the
surface, especially when viewed under a lens.

The hypodermalia are oxypentactins, orthotropal, and mostly with straight
smooth rays, each about 900 x 20u; others are larger, 1000 x 25p (VI. 1b, b’),
with slightly curved wavy rays. a

The autogastralia (VI, 1c) are hexactins, considerably larger than the auto-
dermalia, each ray being 319p in length, and 11°25 in breadth at the base, tapering
to a sharp point, and only sparsely spined.

The intermedia include holoxyhexasters (VI. 1d), hemioxyhexasters (VI. 1d’),
and only rarely monoxyhexasters (VI. 1d’), about 110-1254 in diameter; the
primary rays are 8—10p in length; and the secondary rays are extremely slender.

The caleycocomes (VI. le), 426 in diameter, have short primary rays, 13 in
length, continuing each into a long solid capitulum 40y in length and 16, in breadth,
whence originates a circle of eight to ten finely spined knob-tipped secondary rays.

The holodiscohexasters (VI. 1f, f') of medium size, 125 in diameter, with
short primary rays dividing into four or five disk-tipped secondary rays, oceur
only rarely.

The microdiscohexasters (VI. 1g), 48 in diameter, have their primary rays,

Oat
a “

14 R. KIRKPATRICK.

7m in length, each ending in a convex disk-shaped capitulum, from which arises a
circle of disk-tipped secondary rays in two lengths.

The new species comes very near to &. podagrosa, which it closely resembles
in general shape, in the characters of the orifice and of the marginalia and basalia,
and might perhaps be regarded as a strongly marked variety of that species ; but
R. hexactinophila differs from R. podagrosa in having hexactin autodermalia ; in having
very much larger calycocomes with elongated cylindrical capitula, the capitula in
R. podagrosa being more or less hemispherical; and in having oxyhexasters with
extremely slender secondary rays.

Antarctic Circle, Long. 155° 21’ E., 464 m. (254 fms.).

ROSSELLA RACOVITZ&.
(Plate I., fig. 5, and Plate IV., figs. 1-7.)
Rossella racovitze, Topsent (11, p. x., and 12, p. 33).

The collection contains only one example of this species, which appears, however,
to have been common in the region explored by the ‘ Belgica,’ since no less than ten
specimens and fragments were obtained in four hauls.

The present specimen is 16 mm. in length and 13 mm. in breadth, not including
the pleuralia, which extend 8 mm. from the surface.

The ‘ Discovery’ specimen differs in several respects from those described by Topsent.

The principalia are diactins with roughened rounded ends, sometimes swollen.

The autodermalia are pentactins and stauractins, hexactins being absent; the
rays are thick, slightly spined and a little swollen at the ends.

Just below the surface, along with the oxypentactins, are many thick curved
diactins 1080 x 12

The oxyhexasters are not remarkable except in the smallness of their numbers ;
they appear to be replaced by the discohexasters.

The calycocomes are 225 in-diameter, whereas those of the ‘ Belgica’ are 400p.

The discohexasters, 168 in diameter, are very abundant; the large disks at the
ends of the secondary rays attain a diameter of 16-20, and have long sharp denticles;
these spicules present all the transitions from holodiscohexasters, through hemi- to
mono-discohexasters.

The microdiscohexasters (rare), 56 in diameter, have the secondary rays of only
one length.

‘Discovery, Winter Quarters, Flagon Point, January 17, 1903; Dredge 18-36 m.
(10-20 fathoms).

The ‘ Belgica’ Expedition dredged it in Lat. 70° 15'-71° 15'S. Long. 80° 48'-
87° 39' W. 450-569 m. (247-310 fathoms).

AULOROSSELLA.

Sack- or barrel-shaped Losselline with three kinds of discohexasters, viz.,

calycocomes, medium discohexasters and microdiscohexasters, With surface conules.

HEXACTINELLIDA. 15

With hypodermal pentactins with short, thick, smooth paratangentials, associated with
conules or bundles of pleuralia ; hypodermal pentactins entirely absent from the areas
between the conules.

The new genus resembles ossella in possessing three kinds of discohexasters
including calycocomes, but differs from it in the character and distribution of the
hypodermal pentactins.

In the absence of the hypodermal pentactins from the interconular areas Au/o-
rossella approaches Aulosaccus, in which these spicules are entirely lacking. In
Seyphidium longispina Ij. the same spicules are restricted to the upper part of the
body, and, in that situation, mostly to the conules; but Scyphidium is devoid of
the calycocomes, and so also is Vitrollula Tj. Possibly when pleuralial bundles
are strongly developed, the autodermal surface is less in need of support by means
of a layer of hypodermal pentactins, and these latter become restricted to the conules,
and their paratangential rays become shortened till they disappear altogether.

In Aulorossella levis sp.n. only a very few anchor-like pentactins are present in
the bundles of pleuralia prostalia; but these spicules are very abundant in the
pleuralial bundles of A. crassa, the pentactins being here wholly covered by the
dermal membrane. Apropos of the origin of the anchor-like pleuralia and_basalia,
Schulze observes (8, p. 83): “This leads me to suppose that the anchors are to
be considered as protruded and enlarged hypodermalia.” At first the three species
of Awlorossella described below were placed under Aulosaccus. Prof. Ijima, in his
description of Aulosaccus schulzei \j., the type of the genus Aulosaceus, expressly
states, however (5, 112), that no pentactins enter into the composition of the hypo-
dermal skeleton ; and, further, only two kinds of discohexasters occur.

Apropos of the presence or absence of hypodermal pentactins, it will not, I
think, be out of place to make here a slight correction concerning the species
of Aulosaccus Tjima (5, p. 252 and p. 107), in which genus Prof. ljima_ places
three species, viz., A. schulzei Tjima, A. yimai Schulze, and A. mitsukurii Tima.
If Schulze (7, pp. 30, 100, and 10, p. 176) is right in retaining Calycosaccus for
C. yimai Schulze on account of its markedly pinula-like autodermal and autogastral
hexactins with their long obliquely directed spines, then Aulosaccus contains only
one species, viz., A. schulzei Tjima; the species mitsukurii belongs, as will be
shown below, to Seyphidium.

With regard to Seyphidium mitsukurii Tjima, the British Museum possesses the
specimen referred to by Prof. Ijima (5, p. 121) as O.C. No. 4399, and stated by
him to be specifically identical with the type of Seyphidiwm (Aulosaccus) mitsukurii.
The specimen is badly preserved, and patches of dermal membrane remain only here
and there; but in these patches, and beneath the autodermalia, there are hypodermal
pentactins with orthotropal smooth paratangential rays. Prof. [ima himself says
(5, p. 109): “If A. mitsukurii were only provided with pentactinic hypodermalia
I should have no hesitation in referring it to Seyphidium.” Among the autodermal

16 R. KIRKPATRICK.

stauractins and pentactins are peculiar pentactins with very short, closely-spined
paratangential rays and a long, smooth proximal ray; the proximal ray of the
ordinary autodermal pentactins is thick and closely spined in its whole length. It
is possible that the specimen O.C. 4399 in the British Museum is not specifically
identical with the type specimen of S. mitsukurii Ij. in Tokyo.

Aulorossella includes three species, all new, collected by the ‘ Discovery’ in the
Antarctic Region, viz., Aulorossella pilosa, Aulorossella levis, Aulorossella longstaffi.

AULOROSSELLA PILOSA.
(Plate IL, fig. 1, and Plate VI. figs. 2-2k.)

Sponge in form of an oval slightly compressed sack, having an oval orifice with
thin unarmed margin, the wall provided with large sharp-pointed conuli mostly
with long tufts of diactin and, rarely, anchor-lhke pentactin pleuralia. Gastral cavity
deep, and with a continuous finely pilose surface. With a dense, massive root-tuft
composed of diactins and anchor-like pentactins.

The intermedia include holoxyhexasters

a form in which each primary ray
ends in four or five secondary rays being especially abundant—hemioxyhexasters
and, rarely, monoxyhexasters. There are three specimens of this species, all about
the same size. The largest is 14 cm. in total height, and 9 x 6 em. in diameters
of the body about the middle; the pleuralia extend 3°5 cm. from the surface.
The body-wall attains a thickness of 2 em., and the conuli a height of 7 mm.

The dermal surface shows a fine lace-like network beneath which are seen the
openings of the ostia.

The gastral surface (VI. 2) has a finely pilose appearance when viewed laterally,
and feels rough, these characters distinguishing the species from the nearly related
Aulorossella levis, which has a smooth gastral surface. The surface is finely reticulate,
the meshes being *2 to ‘3 mm. in diameter and ‘2 mm. in depth; the meshes are
formed of strands of hypogastral diactins, bristling with hexactins ; about six meshes
stretch over each of the postica.

Skeleton. The framework is made up of bundles of diactins ; beneath the dermal
and gastral surfaces are numerous thick curved isolated diactins roughened at the
ends ; medium-sized parenchymal hexactins occur only rarely.

Spicules. The principalia are diactins varying greatly in length and diameter ;
they attenuate very gradually to roughened, blunt-pointed ends.

The autodermalia (VI. 2b) are pentactins with the rays straight, thickly spined,
and diminishing gradually to a thick, blunt end; the paratangential rays are each 131
x 18 in diameter, and slightly bent downwards towards the odd proximal ray.

The hypodermalia are pentactins (VI. 2c) with smooth, slightly curved
paratangential rays, each 320 x 40u, making an angle of 70° to 80° with the shaft; a
distal knob or swelling may or may not be present ; the odd proximal ray is 2400u in

HEXACTINELLIDA. 17

length. Sometimes these spicules are found among the diactin plenralia projecting far
beyond the surface, but usually they are situated beneath the autodermal pentactins,
either near the surface or concealed amidst bundles of pleuralia.

The anchor-like basalia (VI. 2a) have four thick, straight prongs, 560 x 80y,
sharply bent, so as to form an angle of about 35° with the shaft.

The autogastralia are completely spined hexactins, each ray being 140 « 12p.

The intermedia. The oxyhexasters vary from 56 to 80pm in diameter; the
commonest form is a holoxyhexaster, with principal rays 8-10p, each ending in four
straight, sharp-pointed secondary rays (VI. 2d); VI. 2d‘ shows a variety’ with curved
secondary rays. Hemioxyhexasters in various grades occur, but are not so abundant
as the first kind; monoxyhexasters are very rare. Fig. VI. 2d° shows a micro-
oxyhexaster 22°8y in diameter, with thick club-like primary rays, each ending in three
prickles.

The calycocomes (VI. 2e, e') average about 130 in diameter, the primary rays
being trumpet-shaped, slender at their origin, and expanding gradually up to a disk-
shaped capitulum; the secondary rays vary in number from three to six. Fig. 2¢
shows a calycocome with the terminal rays curving in at their extremities. Fig. 2f
shows a portion of a larger calycocome, 210 in diameter, with a cylindrical capitulum
partly embraced by the bases of the secondary rays; an axial canal extends about
half-way into each capitulum.

Holodiscohexasters (VI. 2h), 94 in diameter, with short, slender, bifurcated
primary rays, occur only rarely.

The microdiscohexasters (VI. 2k) are 34 in diameter ; each primary ray ends in
a sharp-pointed, conical capitulum.

Dredged from 183 m. (100 fms.) off Coulman Island.

AULOROSSELLA LEVIS.
(Plate IL., figs. 2, 3, and Plate VI., figs. 3-3h.)

Sponge sack-shaped, with an oval orifice with thin unarmed edge. With conules
mostly tufted with pleuralia. Root-tuft formed of a compact mass of tufts of basalia.
Central cavity deep and spacious. Gastral wall smooth, showing sieve-like groups of
openings. Autodermalia pentactins and (rarely) stauractins, autogastralia pentactins,
and toa less extent hexactins. Intermedia including, among other kinds, numerous
hemioxyhexasters and monoxyhexasters.

There are four specimens of this species, one large one of pale yellow colour (A) in
spirit, selected as the type, another (B) much larger, dried, and of dark brown colour,
and two small ones (C, D), in spirit.

The dimensions, in centimétres, of specimen A are as follows :—height, 20; root-
tuft, 5 ; diameters in median horizontal plane, 12 x 10; orifice, 3°5 x 2; depth of
central cavity, 11; thickness of wall, 3; height of cones, 1; length of pleuralia from
surface of sponge, 3.

18 R. KIRKPATRICK.

Specimen B is 27 cm. in height and 32°5 em. in diameter ; the colour is now dark
brown, but Mr. Hodgson states that it was pale yellow when captured; many of the
conules form large, thick, thumb-like projections.

The larger of the two smallest specimens (II. 3) is 3 cm. in height and 2°2 em. in
width, the total height and length, including the pleuralia, being 7 em. Mr. Hodgson
informs me that, on one occasion, he hauled up from 228 m. (125 fms.), No. 6 hole,
a huge specimen, apparently of this species, 2 feet in height and 18 inches in diameter,
but in spite of desperate efforts to secure it, resulting in his arms becoming like a
pincushion, the specimen fell back into the water and was lost.

The dermal surface shows a fine network in which larger and deeper meshes
formed by strands of hypodermal diactins are filled in by much finer square meshes
formed by the autodermal pentactins.

The gastral membrane (VI. 8) is smooth and shows sieve-like groups of small
orifices, which are much larger than those of A. pilosa. The membrane is supported by
bundles of hypogastral diactins which form a network with large meshes ; usually in
each mesh there is one large oval orifice, *5 to 1 mm. in long diameter, with a sharply-
defined thin membranous edge. The sieve-like groups of orifices are separated from
each other by unperforated areas or zones, which are sometimes of considerable extent
in the upper part of the central cavity.

Skeleton. The skeletal framework is constructed of bundles of diactins, and of
large regular hexactins, which latter are especially abundant in specimen B.

Spicules. The diactin principalia are very long and have their ends either
rough or smooth, and sharply pointed (more so than those of A. pilosa). The regular
hexactins (VI. 3a) have thick rays each 960 x 90u, smooth or rough at the ends;
many of these spicules are abnormal in having their “ paratangential” rays curved and
bent away from the normal plane like the ribs of an umbrella.

The pleuralia are usually diactins; a few anchor pentactins occur in the larger,
but many in the smaller specimens.

The basalia are pentactins, which attain a length of 10 em. (VL 3b), and have
very stout prongs, 125 in thickness at the base.

The autodermalia (VI. 3d) are pentactins, with wholly spined rays; each
tangential ray, 113 x 17p, tapers slightly.

The hypodermal oxypentactins (VI. ¢3) are grapnel-like ; they are usually found
entirely below the surface of the conules, but there are only a few in each conule.
Sometimes they project outside among the pleuralia.

The autogastralia are chiefly pentactins (VI. 3d‘), each ray being 150 x 18
and wholly spined ; many hexactins, slightly smaller than the pentactins, also occur ;
at the nodes of the hypogastral network there is usually a hexactin about twice the
size of the autogastral hexactin and with the rays smooth at their bases.

The intermedia. Oxyhexasters. Holoxyhexasters are very rare. Hemioxy-
hexasters (VI. 3e, e') are 120m in diameter, and with almost aborted primary rays.

HEXACTINELLIDA. L9

The monoxyhexasters (VI. 3e”) are fairly common; they are about 100p in diameter.
The calycocomes (VI. 3f, f') are 2204 in diameter, the primary rays being 14y in
length ; the solid hemispherical cup-shaped capitulum is 9 in length and breadth ;
the secondary rays form a plume-like circle of six to eight slender, slightly divergent
rays, tipped with very small disks.

Holodiscohexasters (VI. 3g), 96m in diameter, are very rare; the short primary
rays, 9 in length, divide into two to four secondary rays ending in disks with four
to five sharp recurved teeth. The microdiscohexasters (VI. 3h) are 40p in diameter.

This new species closely resembles A. pilosa in its outward appearance, but differs
from that species chiefly in the structure of the gastral membrane (VI. 3), and in the
absence of the holoxyhexasters, so abundant in A. pilosa.

Numerous macerated fragments, consisting solely of a skeletal framework of
bundles of diactins with large hexactins, and occasionally autodermal pentactins, were
obtained from 10-20 fathoms in McMurdo Bay. These, together with a sack-shaped
skeleton and a tuft, 20 cm. in length, of diactin and anchor-like pentactin basalia, found
by a sledge party on the ice, all belong to Awlorossella levis,

Winter Quarters : (1) two large specimens taken in the trawl 150 yards south of
the ship, in 18-36 m. (10-20 fms.) ; (2) two small young specimens from No. 5 hole
(Seal Hole), August 7, 1902, 325 m. (178 fms.); (3) Macerated fragments from
MeMurdo Bay, 18-36 m. (10-20 fms.).

AULOROSSELLA LONGSTAFFI.*
(Plate II., fig. 4, and Plate VIL., figs. la—k.)

Sponge barrel-shaped, almost solid, with only a very shallow gastral cavity with
wide circular orifice having a thin unarmed edge. Surface irregularly tuberculated and
ridged, pleuralia almost entirely absent (there being only two or three scattered about).
Inferior end without a definite root-tuft, but with a few large conules with a few
basalia. Autodermalia thick pentactins, autogastralia thick hexactins. Amongst the
parenchymalia curious tetractins.

The sole specimen of this interesting species is 6°8 cm. in height, 3°9 em. in
breadth about the middle; the orifice is nearly 2 cm. in diameter, and the gastral
cavity only 1°4 cm. in depth. In its stumpy fleshy appearance, the specimen some-
what resembles a kind of cactus plant. Both the dermal and gastral surfaces are
smooth and glistening, and almost opaque, scarcely showing any trace of a hypogastral
network. The shallow gastral cavity has in its floor two depressions separated by a
ridge.

The skeleton is mainly constructed of bundles of diactins; and in addition to
these, large reeular hexactins are distributed in the sponge body.

* The species name is given in honour of Mr. Longstaff, whose munificent donation of £25,000 made

possible the fitting-out of the expedition,
»)

VOL. III, 4 K

20 R. KIRKPATRICK.,

. Spicules. The prineipalia are diactins varying in length and thickness, but
sometimes very thick and strongly tuberculated at the ends (VII. la). Large regular
hexactins, with rays spined at the ends, also occur. Among the principalia must be
reckoned the remarkable pyramidal tetractins (VII. 1b, b') with usually equal rays
varying in length in different spicules from 320-1000, spined only at the ends.
Sometimes below the point of junction of the rays there is an enlargement, apparently
an aborted fifth ray. Some of the hypodermal pentactins resemble the tetractins in
having their four paratangential rays pyramidal.

A few anchor-like pentactin pleuralia with straight prongs making an acute angle
with the shaft are present.

Only diactins are visible in the few short broken tufts of basalia, but possibly
some of the spicules with broken ends may be pentactins.

The autodermalia (VII. c¢.) are thick, closely-spined pentactins with rays each
169 x 24° 5p.

The pentactin hypodermalia are found beneath the tubercles and conules ; they
vary considerably in shape; in some (VII. 1d’) the paratangential rays make an angle
of 70° to 90°, others (VIL 1d, d’, d*) an angle of 30° to 45° with the shaft; they may
be wholly smooth, but are usually spined at the ends of the prongs.

No less than eighteen of these spicules were found beneath the surface of one conule.

The autogastralia (VII. le) are hexactins with closely spined rays, each ray
bens Ie s¢ 15° 5p.

The intermedia. Oxyhexasters (VII. 1f, f', f?) of the three kinds (holo-, hemi-
and monoxyhexasters) occur, the first and last kind being rare. The diameter is about
11l5p. The calycocomes (VII. 1g, g!), 230u in diameter, have slender primary rays
8°34 in length, and the solid capitulam 12m in length and 8°5u in breadth. The
terminal rays, four to seven in number, are roughened and tipped each with a small disk.
Each ray has an oval swelling (VII. 1g') near its origin and on the inner aspect, at
alternately higher and lower levels. Discohexasters are rare. Fic. 1h shows a
monodiscohexaster 55m in diameter. The axial canals extend only to the end of the
basal thickened part (primary portion) of each ray. The microdiscohexasters (VIL. 1k)
are 40m in diameter, the primary rays being 7*5y in length.

W.Q., June 3, 1903. No. 10 Hole. 238 m. (130 fms.).

ANAULOSOMA.*

Rosselline without a central cavity, but with the gastral surface flat and exposed
at the superior end of the sponge. Without hypodermal pentactins. With oxy-
hexasters, calyeocomes, discohexasters, and microdiscohexasters. The new genus
resembles Bolosoma, Caulophacus, and Aulochone in having an exposed gastral surface.
Among the Rossellinee, Anaulosoma agrees with Aulochone and Aulosoccus in being

* a, privative ; avAn, hall; c@pa, body.

HEXACTINELLIDA. 21

without hypodermal pentactins. Awulochone, which has an everted gastral surface,
differs from the new genus in being stalked, and in possessing only one kind of
discohexaster.*

ANAULOSOMA SCHULZII.
(Plate IIL, figs. 5, 6, and Plate V., fig. 2 a—m).

Sponge shaped somewhat like a molar tooth, with rounded or carinated mamuillee
at the lower end, and with a free gastral surface at the upper end. Surface smooth,
without pleuralia, with a few diactin marginalia at the junction of the dermal and
gastral surfaces. With a few very small tufts of diactin basalia extending downwards
from the mammille. Principalia, bundles of diactins, also hexactins, pentactins,
stauractins, and tauactins. Autodermalia, pentactins ; hypodermalia diactins in bundles
forming a network. Autogastralia, pentactins, with a few hexactins.

There are two specimens (A, C) and two fragments (B, D) of this sponge.
Specimen A (III, 5), the type, from McMurdo Bay, is 6°5 cm. in height, 4°5 em. in
width, and 3°3 cm. in thickness. The texture of the sponge is loose. The thin felt-like
gastral surface, with several thin-edged exhalant orifices, is easily distinguishable from
the lace-like dermal surface, the two being separated by a sharp edge. The oval gastral
surface, 5 x 3 .cm., which occupies the whole upper end of the sponge, slopes down-

ce

wards a little; the largest of the “oscules” is oval, and 1 x *5 cm. in diameter ;
the walls of the large canal into which it leads are lined simply with scattered
canalaria in the form of oxyhexasters. The autogastralia are pentactins, and rarely
hexactins. Two or three deeply curved diactins are present on or near the gastral
margin, but it is doubtful whether they are really marginalia, or, indeed, whether they
belong to the specimen at all. The lower end of the sponge is prolonged into two
rounded extensions, each with a small tuft of basalia.

The small specimen C (III. 6) is somewhat wedge-shaped, the inferior end
narrowing to a ridge, with a small tuft of basalia projecting obliquely downwards and
outwards from only one of the ends of the ridge. The upper end, or gastral surface,
1:1 em. in diameter, is in the form of a small circular area, with one small circular
orifice (1°5 mm. in diameter) of an exhalant canal. Round the margin is a cirele of
small diactin marginalia projecting about 6 mm. The two fragments (B, D) are the
lower halves of broken specimens ; in them the broken surface shows the openings of
numerous canals passing vertically upwards from the base.

In Anaulosoma schulzii there is a marked difference in the appearance of the
dermal and gastral surfaces, the former showing a fine lace-like reticulum perceptible to
the naked eye, while the latter has an opaque, felt-like appearance. This difference is
chiefly due to the arrangement of the hypodermal skeleton. In the dermal region

* T have recently found microdiscohexasters in Aulochone (Crateromorpha) lankestert Kirkp. from South

Africa. These spicules escaped my notice when I first described the sponge (Ann. Mag. N.H. (7) VII., 1901,
p. 457).

»

i Ree

22 R. KIRKPATRICK.

there is the extremely fine square-meshed reticulum formed by the tangential rays
of the autodermal pentactins. Beneath this are subdermal spaces separated by the
proximal rays of the pentactins from the hypodermal network with its much larger
triangular or trapezoidal meshes. The strands of the hypodermal network are formed
of straight tangentially arranged bundles of rather thick diactins. The gastral region,
on the other hand, is without subgastral network and spaces, and the bundles of diactin
principalia are not distinguishable from those of the rest of the parenchyma.

Canal-System and Soft Tissues.—The main exhalant canals run vertically
upwards from base to summit, receiving lateral branches in their course. A section
shows circles of the flagellated chambers opening into the finer canals. The subdermal
trabecular network, and the lining of many of the exhalant canals, are crowded with
masses of knollen-thesocytes, each thesocyte being about 8-10u in diameter. In
unstained balsam preparations these masses of thesocytes are clearly distinguished
by their dark yellow colour ; further, they take a deeper stain with borax carmine
than do the rest of the sponge tissues.

The skeleton is formed mainly of bundles of diactins and of separate large
hexactins, pentactins, stauractins, and tauactins.

Spicules.—The principalia are diactins which vary considerably in length and
thickness, the average kind being about 7560 x 22y, tapering to fine points and
spined at the extremities. The spicules, which, in specimen A, are regarded as possible
marginalia, are in the form of two or three long curved diactins about 5 em. in length.
They have become misplaced, and possibly may not belong to the sponge. The delicate
marginalia in specimen C project about 6 mm., and are about 13 mm. in length.

The little tufts of diactin basalia are about 2°5 cm. in length.

The large regular hexactins (V. 2a) have rays 800 x 60y, slightly spined at the
ends ; large pentactins, stauractins, and tauactins (V. 2b, c, d) also are present.

The autodermalia (V. 2e) are pentactins with rays 172 x 24°5y, closely spined.
Young pentactins with fine, smooth, sharp rays occur both in the dermal and gastral
layers.

The autogastralia are mostly pentactins similar to the autodermalia ; a few small
regular hexactins also occur, especially in specimen C. Plate V., figs. 2f-2f', shows
several modified hexactins and a pentactin from the region round the single exhalant
orifice in specimen C.

The intermedia. Oxyhexasters. Holoxyhexasters (V. 2g), 197, with bifurcate
primary rays, short or almost absent, are pot uncommon; a kind (V. 2g"), 86, in
which each primary ray ends in a disk, whence five to six sharp-pointed secondary rays
diverge, occurs less frequently.

Hemioxyhexasters (V. 29°), about 180m, are abundant; and monoxyhexasters
(Y. 2g°*), also about 180 in diameter, occur, but rarely; fig. 29? shows a hemi-
oxyhexaster in which one of the secondary rays has a trifid termination. (The small
“2” of 29° has been omitted in the plate.)

HEXACTINELLIDA. 23

The calycocomes (V. 2h, h’) are, on an average, about 225 in diameter, the
primary rays being 9 in length; each capitulum, 6°75y in length and 14°5y in
breadth, ends in two to four roughened secondary rays tipped with button-like disks.

Hemidiscohexasters (V. 2k, k'), 100u in diameter, occur but rately ; the primary
rays end in one to three secondary rays tipped with disks having four to six long
recurved teeth. Fig. 21 shows an exceptional form, 91u in diameter, with thick
primary and secondary rays, the latter again dividing into two or three short
branches.

The microdiscohexasters (V. 2m) are 43y in diameter, with primary rays 5°5y in
length, and with a convex capitulum, whence about six disk-tipped secondary rays arise.

Winter Quarters: (1) one specimen (A), the type, and a fragment (B), February 28,
1902, McMurdo Bay, 36 m. (20 fms.) ; (2) a small specimen (C), No. 4 hole, January
30, 1902, 75 m. (41 fms.); (3) a fragment (D), No. 12 hole, September 8, 1903,
45-55 m. (25-30 fms.).

Sup-Famity LANUGINELLIN2.
ANOXYCALYX.
Lanuginellinee without Oxyhexasters, with Graphiocomes.
ANOXYCALYX IJIMAI.
(Plate III., fig. 7, and Plate VII., figs. 2-29".)

Sponge in form of a small compressed pyriform sack, with the surface studded
with small conules and small flattened pyriform buds. With slender tufts of long fine
diactin pleuralia and basalia. The orifice narrow and oval, with a plain rim, and
without marginalia. Autodermalia stauractins (mainly) and pentactins, with the odd
ray proximal, more rarely tauactins and angular diactins; hypodermal pentactins
confined to the conules; autogastralia hexactins, with large microdiscohexasters, with
eraphiocomes, and very large strobilocomes.

The largest of the three small specimens is 2°2 cm. in the length of the body, and
7°5 cm. in total length, ze. including the pleuralia; the greatest width is 1°7 cm.
and the thickness 7 mm.; the slit-like orifice is 4 mm. in width. ‘The largest buds
attain a length of 2 mm.

The skeleton is mainly formed of bundles of diactins.

Spicules. The diactin principalia of the bundles are very slender, wavy,
tapering to fine points, and roughened at the ends; a much thicker kind are isolated, or
with slender comitalia. Pl. VII., fig. 2a, shows a parenchymal triactin x 150. The
slender wavy pleuralia attain a length of 5 cm.

The autodermalia are chiefly stauractins (VII. 2b), with each ray 234 x 12p,
slightly spined, curved inwards, rounded at the end ; occasionally these spicules have

thick club-like rays (VII. 2b*).

24 R. KIRKPATRICK.

The autodermal pentactins (VII. 2b') are fairly numerous ; the odd proximal ray
is spined. Fig. 2b’ shows a tauactin. The rays of the curious angular diactins
(VIL., 2b*) form an angle of 60°.

The hypodérmalia are pentactins (VII. 2c) with long, deeply-curved paratan-
gential rays 1240 x 55p, tapering to a sharp point. In one or two instances these
spicules project out a small distance, and might be regarded as basalia.

The autogastralia (VII. 2d) are hexactins with slender, sparsely-spined
cylindrical rays, each 188 xX 5°6p.

Intermedia. The strobilocomes (VII. 2f, f') are 175 in diameter ; each primary
vay (13°5p in length) ends in a cone or strobilus rounded at the distal end, and giving
off a series of four verticils of long slender S-shaped rays, each tipped with a toothed
disk ; the verticils increase in length from below upwards, the lowest and outermost
being the shortest, and the highest and innermost the longest. The plumes of the
secondary rays are more loosely tufted than is the case in most other species, where
the rays of the verticils and the verticils themselves are more closely packed.

The graphiocomes (VII. 2e, et) are 150” im diameter; each primary ray is
7°25 in length and ends in a broad disk, from the whole distal convex surface of which
a diverging tuft of fine raphide-like rays is given off.

The microdiscohexasters (VII. 2¢, g') are of large size, being 60m im diameter ; the
primary rays end in a circle of disk-tipped secondary rays surrounding a central cone
continued into a ray ending in a disk.

The new genus is near to Lophocalyz, but differs from it and from other genera of
Lanuginelline in having no oxyhexasters.

Pl. VIL, fig. 2, shows a thin section of one of the largest buds, which has an
oscule and central cavity.

The section has been made in a direction slightly oblique to the long axis, and
shows the convex outer ends of the flagellated chambers; although several of these
outer ends have been cut through, the artist has put them in, the figure being a
combination one, and, I fear, slightly diagrammatic.

W.Q., January 2, 1904. No. 14 Hole. 329m. (180 fms.).

INDEX OF MEMOIRS REFERRED TO IN THE REPORT ON THE
HEXACTINELLIDA.

1, Carrer, H. J.—* On two new Sponges from the Antarctic Sea... .” Ann. and Mag. Nat. Hist.,
1872 (4) ix., p. 409.

Carter, H. J.—* On the Genus Rossella ... .’ Ann. and Mag. Nat. Hist., 1875 (4) xv., p. 113.

Hopason, T. V.—The Geographical Journal, April, 1905.

Tsma, I.—Studies on the Hexactinellida.” Contribution iii. Journ. Coll. Sci., Tokyo, 1903,
vol. xvili., art. 1.

5. Ista, I.—*Studies on the Hexactinellida.” Contribution iv. Journ. Coll. Sci., Tokyo, 1904,

vol. xviil., art. 7 (Rossellide),.
6. Scuuuze, F. E.—‘ Challenger’ Report on Hexactinellida, 1887.

Em fis

HEXACTINELLIDA. 25

7. Scnutze, F. E.—Amerikanische Hexactinelliden . . . der Albatross-Expedition. 4°. Jena, 1899.
8. Scnutze, F. E.—‘An account of the Indian Triaxonia collected by the . . . ‘ Investigator.’
Translated by R. von Lendenfeld. Calcutta, 1902.
9. Scuutzz, F. E.— Caulophacus arcticus und Calycosoma gracile.” Abhand. Konigl. preuss. Akad.
Wiss. 1903.
10. Scuunzn, F. E.—‘‘ Wiss. Ergebnisse der Deutschen Tiefsee Expn. . . . ‘ Valdivia.” Hexactinellida,
1904.
11. Torsenr, E.—“ Notice préliminaire sur les Eponges de l’expédition antarctique Belge.” Arch. Zool.
exp. eb gén., 1901 (sér. 3), vol. ix.
12. Torsent, E.—* Résultats du Voyage du 8.Y. ‘ Belgica’ in 1897-99.” Spongiaires. 1902.

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MARINE ALGA.
at aOPAYCH A, AND FLORIDEA,.
By Antony Gepp, M.A., F.L.S., and Eruet 8. Grpp.

(Four Plates.)

TuHoucH the number of species, apart from the Corallinacee, collected within the
Antarctic Circle by the British Antarctic Expedition is but small, and the specimens
themselves are mostly fragmentary and badly preserved, yet among them are included
some interesting novelties. Some of these were briefly described in the Journal of
Botany, April, 1905, pp. 105-109, with the ale of the Scottish National Antarctic
Expedition. One of them, which is common to both collections, Gracilaria simplex
(Leptosarca simplex), is unfortunately only represented in the present collection by
dried and crushed material; and though it is markedly distinguished by its
vegetative structure, the details of this could not be worked out until the clue was
given us by some pickled material in the ‘Scotia’ collection. A second species of
Gracilaria, G. dumontioides, comes from Cape Adare, and is extremely interesting
from the point of view of distribution, for it appears to be the same as an Arctic
species which was collected in 1853 by Dr. David Lyall in the very northerly latitude
of Northumberland Sound, and was named Halosaccion dumontioides by Harvey, but
never described ; for he had dried sterile material only, in which, through the collapse
of the inner cells, the structure is obscured.

Magnificent specimens of Lessonia grandifolia were brought back by the
‘Discovery, the largest lamina attaining a length of 24 feet before it was dried.
Infant plants of the same species (about one inch long) were found attached to
Desmarestia harveyana. We erroneously recorded (Journal of Botany, loc. cit.)
L. grandifolia as having been collected in the South Orkneys by the Scottish
Expedition. Though we found the two plants so much alike in external habit, we
have been compelled, after a further examination of their minute structure, to separate
them specifically. The ‘ Scotia’ plant will be found below, described under the name
L. simulans. The oceurrence of two such large new species of alge is a rather
startling indication of how much may yet remain to be investigated in the South Polar

marine flora.

~

VOL. III. ZL

bo

ANTONY GEPP AND ETHEL S. GEPP.

A small plant of Zonaria was found, which is too young to identify ; but it is
interesting as the first record of this genus from the South Polar regions.

Desmarestia harveyana (D. media of the Flora Antarctica) appears to have been
abundant, and a specimen of over six feet in length has been brought home in the
collection.

Phyllophora antarctica is the Antarctic congener of the northern species
P. interrupta.

Spongoclonium orthocladum is a new species, allied to S. hirtum (Callithamnion
hirtum of the Flora Antarctica).

The conditions of life that control the algal flora at both poles are peculiar,
and are not easily realised by those who have never visited the polar regions. The
two totally distinct seasons—on the one hand, the prolonged winter night, together
with the impenetrable crust of ice that effectually cuts off the sea from contact with
the gases of the atmosphere sometimes for years, the increasing salinity of the water,
due to the rejection of salt during the formation of the deep layers of ice, the
equable, low temperature of the denser, deeper waters below the ice; on the other hand,
the long summer day, accompanied by the breaking of the ice and melting of the
ice and snow, the layer of fresher water on the surface, which slowly mingles with
the sea-water below, the renewed absorption of atmospheric gases, the assimilation of
carbonic acid excreted by the animals living there—these and other factors must
profoundly influence and modify algal life and development; and data concerning
the effect of these conditions upon alg have yet to be accumulated.

A critical comparison of the marine floras of the two Polar regions should bring
out points of great interest ; and a fair field in this respect lies open to that expedition
which is the last to publish the report of its collection of marme alge. Any attempt
to draw up such a comparison now would necessarily be premature and incomplete.
We await with interest the publication of the results of the other expeditions, in
the hope that they may yield a more complete representation of the algal flora
peculiar to the Antaretic region, and that incidentally they may throw light upon
those points which we are compelled to leave in obscurity.

PHAOPHYCE/E.
1. ZONARIA sp.

Off Cape Wadsworth, Coulman Island.

A small, immature plant, 2 em. high, the thallus of which is still monostromatic
throughout. Though unable to name the species, we think it worth while to include
the plant in our list, as the genus has not yet been recorded from the far South.

Zonaria is here used in its old and wide sense, as the specimen is too fragmentary to
admit of further classification.

MARINE ALGAAS. 3

2. LESSONIA GRANDIFOLIA.
(Plates I. and I, figs. 5-9.)
Lessonia grandifolia, Gepp, Journal of Botany, 1905, p. 105.

Callus radicalis dense et irregulariter ramosus, coriaceus. Stipes valde com-
pressus, marginibus obtusis, bis vel ter vel quater dichotomus, subter quamque
dichotomiam complanate expansus ; rami sectione transversali plano-convexi ancipites
marginibus acutis, laxe torti. Stipes totus e callo usque ad laminas 30-120 em.
Laminz lanceolato-lineares longissimae (1-8 met.), latee (8-45 cm.), marginibus grosse
undulatis integerrimis, apice deleto, fissiles, in statu sicco coriacesw sed fragiles.
Stipitis substantia lacunis annulisque carens. Lamine substantia coriacea e stratis
tribus composita; cellulis corticalibus minutis fuscis congestis in series verticales
breves dispositis; subcorticalibus rotundatis 1—-2—seriatis quam corticalibus
magnitudine duplo majoribus ; hyphis medullaribus hyalinis extrorsum dense introrsum
laxe invicem juxtapositis flexuosis tubulos multos subinfundibuliformes vagina e cellulis
parvulis composita vestitos circumstantibus. Zoosporangia ignota. Figs. 1—9.

Cape Adare (Jan. 9, 1902), hauled up with anchor from 18 fathoms; Coulman
Island, off Cape Wadsworth, 18 fathoms.

In our previous account of this species (Journal of Botany, /.c.) we quoted
specimens gathered both by the Scottish and the British Expeditions, and from the
order in which they were cited it would naturally be inferred that the type described
was the ‘Scotia’ plant. We wish to state that the type was and is the ‘ Discovery ’
plant, and that the diagnosis was founded upon it alone, the ‘Scotia’ material being
too fragmentary to furnish data for a complete description. Though at the time we
regarded the ‘ Scotia’ fragments as belonging to L. grandifolia, we are now convinced,
after having examined more carefully their microscopic structure, that the ‘Scotia’
and ‘ Discovery’ plants must be distinguished specifically. We therefore describe
them both in detail.

LL. grandifolia is one of the larger species of Lessonia, but is not one of the
dendroid members of the genus, that is, it has not the sturdy, round, tough, persistent,
well-developed stem, apically branched, and showing rings of secondary thickening,
which is so marked a feature of LZ. fuscescens and L. nigrescens. In L. grandifolia the
stem is subsidiary to the laminz, and the species is distinguished from all the rest of
the genus by the great size of its unsplit lamine; the largest lamine previously
recorded for any of the species were 60-90 cm. in length, and occurred in L, fuscescens,
Bory (Hooker, Flora Antarctica, I. 1847, p. 458).

In our specimens of JZ. grandifolia the largest lamina is 5°7 m. when dry,
and, when first taken out of the formalin solution in which it was preserved, measured
7°3m. in length hy 45 em. in width. Another lamina measured 4°5 m. by 35 cm.
wide when moist before desiccation. None of the mature fronds are complete at the
apex, but we are unable to say whether or not this means that the previous year's

> )
2La

4 ANTONY GEPP AND ETHEL S§8. GEPP.

growth has died off above. These lamin are simple, with undulate margins, and in
this respect resemble somewhat those of Laminaria saccharina; but are of course far
larger, and arise from a branched stem (figs. la and 1b).

The main stem is attached to the substratum by a dense ramified mass of leathery
holdfasts, and is very short (15-22 em. long), much compressed (5 em. wide by about
1°5 em. thick), in transverse section concavo-convex with rounded margins (fig. 3a,
diagrammatic). It is divided above dichotomously into two branches which are much
compressed, two-edged, laxly twisted, simple or 2-3 times dichotomously branched,
and much flattened and expanded below each dichotomy. These branches vary in
length from 15-105 em., the younger branches being the longest; they gradually
taper upwards, and before expanding gradually or quickly into the great flat fronds,
are reduced to a width of 1°5-2°5 em. when moist, and 0°3-0°7 cm. when dried. At
this thinnest point they tend to decay most readily when being dried.

The branching of LZ. grandifolia is dichotomous, and we can find no indication in
either the mature or very young specimens that the dichotomies are the result of a
splitting of the developed frond such as is characteristic of some of the other species
of Lessonia, Further, in some very young plants (fig. 2) of LZ. grandifolia, which we
found growing on Desmarestia harveyana, it is interesting to note that though but
1-2 inches long, they are already as much branched as the huge mature plants; and
this shows that the dichotomous branching occurs very early in the life-history of the
plant, and is not a feature of subsequent development.

The structure of the mature lamina, as seen in transverse section (fig. 5a), consists,
like that of the stem and branches, of three strata. Externally is a cortex of small
brown cells, placed in short vertical rows, and crowded ; beneath it is a subcortical
stratum of about 2 rows of rotundate cells twice as large as the cortical cells, and
containing a coloured globose mass of contracted protoplasm. This subcortical stratum
passes almost at once into the closely packed, short-celled, irregularly flexuose, longi-
tudinal hyphe which form the external limit of the medulla and which in transverse
section form a band of tissue apparently composed of 8-10 rows of subrotundate cells
of varying size; the interior of the medulla is composed of hyaline hyphze mostly
running longitudinally, laxly juxtaposed in the gelatinoid matrix and separated from
one another by 1-2 times their diameter. Embedded in this medulla and dotted
along an irregular median line, which stretches across the lamina from edge to edge,
are a number of trumpet-hyphe, rather resembling those described by Grabendérfer
(Bot. Zeit., vol. XLII, 1885, p. 645, tab. VI, fig. 11) for ZL. ovata, but unlike the
latter, they are enclosed each in a sheath of very small cells (fig. 5b). These trumpet-
hyph run in a sinuous course both longitudinally and transversely, and are found
even in the youngest plants. They serve, perhaps, as mucilage tubes. When seen in
longitudinal section (fig. 7), they exhibit on their walls very fine and faint transverse
striations (confer fig. 9). We have failed to find any such trumpet-hyphe at all in
any other species of Lessonia (except L. simulans; see p. 6), e.g. L. fuscescens, L.

MARINE ALG. 5)

nigrescens, and L, littoralis; and even in L. ovata the “ Trichter” (as Grabendérfer
calls them) differ in being more inflated at their funnel-shaped ends and quite
destitute of a special sheath.

In the very young lamina (J in. long), the structure is much simplified (fig. 6).
The cortical cells are crowded, and obscured by coloured granules and form a mono-
stromatic layer, beneath which is the subcortical stratum of about 2 rows of large cells,
round in transverse section, or sometimes twice as long as broad in longitudinal section
of lamina (fig. 8). In the middle les the medulla, consisting of some three or more
rows of longitudinal or transverse hyaline hyphe ; among them are very few trumpet-
hyphee, each in its sheath.

As to the structure of the stipes, it is im the main similar to that of the mature
lamina, but the cortex is a little thicker and more deeply coloured, the medulla is
far thicker and the sub-cortical layer much less distinct. In a transverse section
there is a narrow, more opaque, median band stretching right across, along the widest
diameter, distinctly visible to the naked eye (fig. 3b). This, under a low power of the
microscope, is seen to contain dots and streaks (fig. 3c, and 4), which, under a higher
power, are seen to be trumpet-hyphe in transverse and longitudinal section (fig. 9).

The structure of the basal holdfasts is simple, the main tissue being composed of
thin hyaline hyphe mainly longitudinal, most of them exhibiting a contracted globose
mass of coloured protoplasm ; this tissue contains no ensheathed trumpet-hyphze and
passes gradually through a cell-like subcortex to a submonostromatic cortex of small
cells obscured by coloured granules.

Neither stem nor lamina possess any lacune like those that characterise L.
nigrescens and other species.

L. grandifolia resembles our L. simulans in external habit, but differs in structure,
as we show under that species. It also approaches LZ. laminarioides in habit, but
differs from it in being 10-20 times as large, in having the stems flat and twisted, and
the medullary hyphe interspersed with the ensheathed trumpet-hyphe mentioned
above. J. ovata, though, as we have said, possessing trumpet-hyphe somewhat like
those of our plant, is otherwise very different, having small oval lamin less than
20 em. long, and a stem which, according to Grabendorfer (op. cit., p. 643), may attain
a leneth of several metres and a thickness of about 10 cm.

3. LESSONIA SIMULANS.
(Plate II., fig. 16.)

L. simulans Gepp, Journal of Botany, 1906, p. 425.
L. grandifolia, pro parte Gepp, op. cit., 1905, p. 105, tab. 470, fig. 6.

Planta incompleta. Frons laminarioidea ut in L. grandifolia, stipite complanato
ancipite suffulta simplex, lanceolato-linearis, longa, lata (12°5 em. plusve) marginibus
integerrimis. Laminae substantia pergamentacea vel coriacea e stratis tribus com-

posita ; cellulis corticalibus monostromaticis quadratis eranuloso-obscuris ; subcorti-

to)

6 ANTONY GEPP AND ETHEL S. GEPP.

calibus oblongis parenchymaticis in circa 6-7 series dispositis; medullaribus elongatis
angustis strictis 9-10 seriatis tubulos perpaucos subinfundibuliformes vagina e cellulis
parvulis composita vestitos foventibus. Caetera desunt (fig. 10).

South Orkneys, Scotia Bay, near surface ; April, 1904, leg. R. N. Rudmose Brown.

A section of the lamina of this plant was figured in the Journal of Botany (Joe.
cit.) as representing that of LZ. grandifolia. We had at the time no doubt that the
‘Scotia’ specimens which, though fragmentary, presented so striking an external
likeness to the type, were identical with it; for such differences of structure as were
apparent seemed to be due to a different method of preservation. The ‘ Scotia’
specimens were preserved in spirit, and exhibited a simpler and clearer cell-structure
than the ‘ Discovery ’ material, which was preserved in formalin or merely dried. But,
after having made a more careful comparison of their microscopic structure, we are
convinced that the ‘Scotia’ plant must be separated off as a proper species, though the
material is insufficient to enable us to describe its complete habit.

As regards the structure of the lamina, the cortex is monostromatic and composed
of quadratic thin-walled cells with granular contents (not rotundate and densely
obseured, as erroneously figured in the Journal of Botany, loc. cit.). The subcortical
tissue consists of about six layers of larger cells, rounded or oblong, lengthened parallel
to the axis of the frond; and the medulla is composed of some nine to ten rows of
narrow elongated cells, thick-walled, with a few ensheathed trumpet-hyphe scattered
among them. The medullary cells are sometimes filled with a pale brown mucilage,
and their limits are then barely distinguishable.

In the stipes the medulla is the main tissue, and consists of a dense pale-brown
mass of hyphe, chiefly longitudinal (fig. 10) and straight, but here and there mingled
with interwoven hyphze. Scattered in the medulla are a very few trumpet-hyphe,
some with and some without a sheath of very small cells. The medulla externally
changes into a pluristromatic subcortex of large round and oblong cells which, passing
outwards in radial rows and subdividing, gradually changes to a cortex of three to four
rows of small quadrate cells, bounded by distinct cuticle.

The structure of the holdfasts rather resembles that of the stipes, but the strata
are less definitely marked ; there is a dense medullary mass of hyphze which towards
the periphery change into lax, larger, thm-walled subcortical cells, and these in their
turn becoming smaller and smaller, pass into a cortex of small dense-coloured quadrate
cells. There are no trumpet-hyphe in the medulla of the holdfasts.

The most obvious difference between LZ. stimulans and L. grandifolia is found in the
medulla of the lamina. This in the former plant isa very pale-brown tissue of elongated
cells with very few ensheathed trumpet-hyphe. In L. grandifolia the medulla is
colourless and composed of hyph mostly longitudinal, and laxly juxtaposed and
separated from one another by one to two times their diameter. The ensheathed
trumpet-hyphze are numerous and obvious, and scattered along an irregular median line.
L, simulans differs also in having a monostromatic cortex of quadrate cells,

MARINE ALG. 7

It might be urged that LZ. grandifolia and L. simulans are sufficiently distinct
from Lessonia to constitute a separate genus on account of the following characters :—
The laminz are huge and undergo no multiplication by longitudinal splitting, the stem
is poorly developed and exhibits no rings of secondary thickening, and no lacunz are
present in lamine and stem; moreover, LZ. grandifolia is markedly characterised by
the presence of numerous trumpet-hyphe in the medulla, as also is L. simulans to a
lesser extent. But though, at one time, we were tempted to separate these species from
Lessonia, we feel that such intermediate links as L. /aminarioides and L. ovata are too
strong to admit of a generic separation, however great the contrast may be between our
plants and the typical dendroid species, L. fuscescens and L. nigrescens, upon which
the genus was founded. Further, we would suggest that whereas L. fuscescens and
L. nigrescens are evidently sturdy perennials, L. grandifolia and L, simulans, with their
weak stems, may possibly be mere annual or biennial plants. Moreover, as mentioned
in the introduction, the local conditions of life in the Antarctic Ocean are peculiar, and
though during the long winter night the growth of our two species may be inhibited, or
even replaced by decay, yet during the perpetual daylight of summer they may
possibly have a special capacity for rapid growth, and thus perhaps attain in one season
the huge dimensions of our specimens. If such be the case, we would suggest that the
trumpet-hyphee, the actual function of which is unknown to us, may perhaps facilitate
rapid growth by providing channels for the ready transference of food-material and
waste products. That these trumpet-hyphe are connected in some way with the local
conditions of life seems evident from the abundant occurrence of similar ensheathed
hyphe in Desmarestia harveyana (figs. 14a, 13b), an Antarctic species which grows to a
considerable length.

4. DESMARESTIA HARVEYANA.
(Plate IIL, figs. 11-15.)
Desmarestia harveyana, Gepp, Journal of Botany, 1905, p. 106 (figs. 11-15).

D. media Hook. f. et Harv. Flor. Antarct. IT. (1847), p. 466 ; Kiitzing, Tab. Phyc. IX. (1859), tab. 95,
fig. II.; haud Grey. Synops. (1830), p. XL.

D. aculeata var. compressa Reinsch in Flora, 71 (1888), p. 190; et in Internat. Polarforsch. 1882-1883,
Deutsch. Exped. Band IT. (1890), p. 408, tab. XVIT., fig. 3.

Off Cape Wadsworth, Coalman Island, 18 fathoms ; Cape Adare, February 24, 1904.

Geogr. Distrib.—Cockburn Island. South Georgia.

Specimens of this plant were preserved both dry and in formalin. One of the
latter is as much as 6 feet long, but being incomplete, must have been longer still when
growing. They agree absolutely with those from Cockburn Island, collected by D. Lyall
on Ross’s Antarctic Expedition (1839-1842). Lyall’s specimens in the British Museum

-are named D. media in Harvey’s MS. Harvey, indeed, was strongly of opinion that
they are identical with D. media Grev., ie., Sporochnus medius C.Ag., collected at
Unalaschka by Chamisso, and figured by C. Agardh in his con. Alg. ined., tab. 16
(1822). Although we have not seen Agardh’s type, we are so convinced that it is

8 ANTONY GEPP AND ETHEL S. GEPP.

distinct from our Antarctic plants that we are compelled to separate these latter off
under a new specific name. Agardh’s plant appears to have stem and branches terete,
and the branches become gradually thicker towards their base as they are traced down-
wards into the stem. In D. harveyana the stem and branches are flat when dry,
elliptical when moist, and the branches gradually become attenuated towards the base
before joining the stem. Setchell and Gardner (Algew of N.W. America, 1903, p. 247)
also keep these plants separate, maintaining that the Antarctic D. media Kiitz. (Tab.
Phye. IX., p. 40, t. 95, IT.), which equals D. harveyana, is not the same as the North
Pacific D. media (Ag.), Grev., which they call D. aculeata, var. media J.Ag. Under
the latter name they cite No. 353 of Tilden’s American Algz, a specimen of which we
have examined. It bears a descriptive label saying “stem and branches traversed
(axially) by an articulated filament surrounded by a layer made up of larger (air
cavities) and smaller cells.” This we take to be the structure of typical D. media Ag. ;
and we do not find it to be identical with the structure of D. harveyana. For in D.
harveyana a transverse section of the elliptical stem (fig. 13a) shows, in addition to the
primary axial articulated filament, two or more parallel articulated tubes cut across and
situated at irregular intervals more or less on the longest diameter of the ellipse,
running longitudinally up and down the stem, each of the tubes being ringed round by a
sheath of small cells (pl. iii., figs. 13b and 14b). The actual position and inter-relations
of these tubes are at once seen upon examination of a fairly thick median longitudinal
section (fig. 14a), cut parallel to the flattened surfaces of the complanate thallus.
Sufficiently good sections are quickly obtained by the rough-and-ready method of
shaving off the opaque cortex and then slicing down the flat medulla with a sharp
scalpel, the material being held gently between finger and thumb. The primary
filament with its septa and sheath of minute cells is then visible in the axis of the
thallus. At intervals it puts out on one or other side a lateral tube which bends
upwards, and after running subparallel to the axis for about 4 mm. turns outwards into
the next lateral branch above (fig. 14a). There are also two or more thinner secondary
tubes parallel to the axial filament, sheathed, and dividing usually at long intervals ;
these divisions anastomose with one another here and there, and occasionally with
the main filament. We think it possible that these tubes are the “ einzelne nicht
regelmiissig vertheilte gréssere Zellen, umringt von um die Hiilfte klemeren”
described by Reinsch (Flora 71, 1888, p. 190) as characteristic of his South
Georgian D. aculeata, var. compressa, which plant would then bea synonym of
D. harveyana.

One of the forms recorded from the southern oceans is D. viridis var. distans
Hook. et Harv., specimens of which are preserved in the British Museum. Though
they somewhat resemble D. harveyana in habit, they differ from it in structure. The
structure is comparable with that of typical D. viridis. A figure (fig. 16) is given here
of a transverse section of the thallus of D. viridis var. distans, for comparison with
that of D. harveyana.

MARINE ALGA, 9

While referring to the southern species of Desmarestia, it may be worth while to
point out a slight error in the key to the species which Reinsch publishes in Flora, 1888,
pp. 189, 190. He classes J. chordalis with D. viridis as having its ultimate pinnules
uncorticated. He had apparently never seen D. chordalis, and he misinterpreted
Harvey's “apice longe nudis” (Flor. Antarct. Part IL, p. 467) as meaning uncorticated,
whereas it simply means unarmed with spinules. We would point out that in D.
harveyana the axial hyphe are corticated to the very tips of the ultimate ramuli
(fig. 12).

5. EcrocaRPUS GEMINATUS.
Ectocarpus geminatus Hook. et Harv., London Journal of Botany IV. (1845) p. 251.

Cape Adare, with plurilocular sporangia, epiphytic on Desmarestia harveyana.

Geogr. Distr.—Cape Horn, Falkland Islands, Kerguelen.

This species is well figured by Hariot in Mission Scientifique du Cap Horn
(1882-3), tom. v. 1889, Algz, pl. 3, figs. 1, 2. Our attention has been called by Dr.
Carl Skottsberg to Reinke’s note in the Atlas Deutscher Meeresalgen II. 1892, p. 46,
where he proposes to transfer this species to the genus /sthmoplea.

FLORIDEZ.

6. [RIDAA MICANS,
Tridea micans Bory, Voyage Coquille, 1828, p. 110, tt. 13, 138,

MeMurdo Strait, upon the ice of Bay between Black and White Islands, among a
heap of sandy matter, a mile north of rock-débris heaps, five miles north of tide-crack
at head of bay, September 14, 1902.

Geoer. Distr.—Falkland Islands, Cape Horn, Valparaiso, Auckland Islands.

A fruiting specimen, weathered, faded and fragmentary.

7. GRACILARIA sp.

Off Cape Wadsworth, Coulman Island.

A fragment without fruit. The habit is that of G. multipartita, and a transverse
section of the thallus shows the large thick-walled inner cells, surrounded by smaller
ones.

8. GRACILARIA SIMPLEX.

G. simplex, Gepp, Journal of Botany, 1905, p. 195.
Leptosarca simplex nob. op. cit. 1905, pp. 108, 162.

Frondes plures (8-10) e callo minuto orte simplices oblong vel lato-cuneatz
plane membranace, 10-15 cm. long (apice destructo), 3-8 cm. late, ¢c. 230.

VOL. II. 2M

10 ANTONY GEPP AND ETHEL §8. GEPP.

crassee, inferne in stipitem plus minusve sensim augustatum, 1-3 cm. longum
attenuate, stratis duobus contexte cellulis interioribus rotundato-angulatis magnis
2-3 seriatis pachydermis (frondis sterilis majoribus maxime leptodermis collabentibus
submonostromaticis) ; cellulis corticalibus filamenta ramosa verticalia efficientibus,
tetrasporangia magna cruciatim divisa foventibus (frondis sterilis majoribus mono-
stromaticis).

Off Cape Wadsworth, Coulman Island.

Geogr. Distr.—South Orkneys.

This species is represented in the ‘ Discovery ’ collections by one specimen only, a
single thin dried frond 22°5 em. long by about 1°5 em. broad at its widest part.
Blunt and incomplete at apex, it tapers very gradually down to its attenuated stalk-
like base. This frond is quite sterile, and owing to the collapsed condition of its cells
as the result of drying, was not in itself sufticient for determination, for we altogether
failed to make the ceils swell out again. Fortunately we found in the ‘Scotia’
collection from the South Orkney Islands two specimens, which clearly belong to the
same species, and being preserved in spirit, and uncrushed, revealed to us the interior
tissue in its natural condition. These ‘Scotia’ specimens were also sterile, and we
described them under the name Leptosarea simplex (loc. cit.). Subsequently we
received a more complete plant, also from the 8. Orkneys, which with a few other alge
had been overlooked in the ‘Scotia, until she was cleared out previous to being sold.
This plant bore ten fronds, some sterile, others tetrasporiferous. ‘The two kinds of
frond exhibited differences of structure, the sterile being characterised by an internal
layer of large, extremely thin-walled cells, bounded by a monostromatic cortex, as
described for Leptosarea (loc. cit.), while the sporiferous fronds with their large cruciate
tetraspores, thicker-walled internal cells and pluristromatic cortex compelled us to
transfer this species to Gracilaria, of which genus it should perhaps form a new section.

9, GRACILARIA DUMONTIOIDES.
(Plates III. and IV., figs. 17-20.)

Halosaccion dumontioides Hary. ex Dickie, Journ. Linn. Soc. LX. (1867), p. 239 (nomen tantum).
Leptosarca dumontioides nob. in Journal of Botany, April, 1905, p. 108 (nomen tantum).

Frons (vetusta incompleta) linearis, 6°5 longa, 4 mm. lata, complanata, membra-
nacea, prolificationes plurimas, intervallis irregularibus cire. 4 mm. latis invicem
separatas, Maxime e marginibus ambobus emittens ; prolificationes 4-15 em. longe
infra medium valde attenuate tunc sensim sursum expansze vel anguste lineares 4mm.
latze simplices vel cuneato-lineares latiores apicem versus dichotome, ramis valde
divergentibus. Color rosaceo-ruber. Cystocarpia et tetrasporangia ignota.

Northumberland Sound, 76° N. lat., July 1853, leg. D. Lyall (fig. 20); Cape
Adare, 72° §. lat., February 24, 1904 (fig. 17).

The only Antarctic specimen (fig. 17) which we have seen consists of a scrap of
an old frond, destitute of base and apex, encrusted by a zoophyte, and bearing laterally

MARINE ALGAAS. 1]

from its edges about fifty proliferations. The whole plant is quite sterile, of very
thin texture, and consists of an internal tissue enclosed in a cortex which is mono-
stromatie except at the margin. The structure, however, owing to the crushed
condition of its interior cells, affords hut little clue to the systematic position of the
plant, and all our efforts to make the internal tissue swell out to its original dimensions
were in vain. We were therefore unable to figure the structure except near the much-
thickened margin of the proliferating scrap of old frond mentioned above (fig. 18).
The cells of the monostromatic cortex are large (fig. 19).

In habit it resembles Dumontia, but has not the hollow thallus and filamentous
cell-structure of that genus. Our plant has a solid thallus, and for that reason we
should not have searched for it under Halosaceion, but strangely enough we find
the Cape Adare plant to be apparently identical with L. dwmontioides Harv., an
undescribed species from the far North. The habit, the thin texture, the mono-
stromatic layer of rather large coloured cortical cells, and the permanently collapsed
internal tissue are the same in both. The proliferations in Harvey’s plant are linear
and very long (fig. 20); in the Cape Adare plant they are half as long, and are
cuneato-linear and tending to be forked at the apex. Dickie (Journ. Linn. Soe. IX,
[1867], p. 239) stated that H. dumontioides was first described by Prof. Harvey
from specimens found by Dr. Lyall in Lat. 76° N. We failed, however, to find any
published description, and applied to Dr. E. Perceval Wright, Keeper of Harvey’s
herbarium, Trinity College, Dublin, for information. He kindly replied :—“<T think
that a description of Halosaccion dumontioides has never appeared. Dr. Lyall’s
specimens were collected in July, 1853. Harvey was on his Australian tour, 1853-56,
and in 1857 was busy with his Phycologia Australica (1858-1863). All our sheets
with Lyall’s specimens are marked in pencil with the name and ‘Harv. MS. Now
when Harvey published a name, he mostly wrote the name in ink on the sheet. On
one of our sheets he has written, still in pencil, ‘Can this be a var. of //. ramen-
taceum?’ It is strange that J. G. Agardh did not write to’me for a specimen in
1876.”—that is, before publishing his pierisis.

Harvey, having only dried material to work upon, aml being therefore unable to
determine the character of the internal tissue, was in doubt as to the aflinity of the
plant, and placed it in /Talosaccion near H. ramentaceum. There we should have been
compelled to leave it, had we not found a similar crushed tissue and monostromatic
cortex in another species, Gracilaria simplea, of which we had received not only dried
specimens, but also spirit material, and to which we regard our plant as closely allied.
However, none of the specimens of either species have cystogarps, and their systematic
position may have to be reconsidered later.*

Dickie (Joc. cit.) records plants collected in Cumberland Sound (66° N, lat.) by

* Since these lines were sent to press we have seen some very fine Antarctic specimens, collected by Dr. C.
Skottsberg during the Swedish South Polar Expedition, which lead us to believe that our Antarctic plant is not
fully grown, and is not conspecific with Harvey’s plant of G. dwmontioides. Dr. Skottsberg will deal with the
question in his own report.

12 ANTONY GEPP AND ETHEL 8. GEPP.

James Taylor. These are in the British Museum, and are small (about 10 cm. long).
They appear to be the same species, but are stouter in texture. Lyall’s specimens, of
which there are fine examples in the British Museum and in the Kew herbarium,
measure 30-40 cm. and bear the MS. note—“ a small specimen.” They were collected
in Northumberland Sound, Queen’s Channel (76° 5’ N. lat., 97° W. long.) on July 14,
1853, during Belcher’s Expedition.

The distribution of the species is notable. It occurs only in the extreme north
(76° N. lat.) and in the extreme south (72° 8. lat.).

10. PLocAMIUM COcCINEUM.
Plocamium coccineum Lyngb., Tent. Hydroph. Danic. 1819, p. 39, t. 9
Off Cape Wadsworth, Coulman Island, with cystocarps.
Geogr. Distr.—Mediterranean, N. and 8. Atlantic, N. Pacific, Cape of Good Hope,
Australia, Tasmania.
11. DELESSERIA QUERCIFOLIA.
Delesseria quercifolia Bory, Voyage Coquille, 1828, p. 186, t. 18, fig. 1.
Off Cape Wadsworth, Coulman Island.
Geogr. Distr.—North Pacific, Falklands, Cape Horn, Kerguelen.
Sterile and somewhat battered specimens.

12. PHYLLOPHORA ANTARCTICA.
(Plate IV., figs. 21 and 22.)
Phyllophora antarctica Gepp, Journal of Botany, 1905, p. 109.

Off Cape Wadsworth, Coulman Island.

Frons e stipite brevi mox in laminam membranaceam ligulatam seepius opposito-
sinuatam simplicem vel dichotomam expansa, ramis approximatis sinu angustissimo et
ad apicem et secundum margines prolificantibus ; cystocarpiis marginalibus pedicellatis ;
tetrasporangia ignota (figs. 21, 22).

This species is represented in the collection by several specimens, both fertile and
sterile, mostly fragmentary, and exhibiting considerable variability of external form
(fig. 21b). The longest specimen (fig. 21a), though incomplete, is about 17 cm. high
and about 1 em. broad, with a single dichotomy. The smallest complete specimen is
5 em. long and unbranched. The lamina is membranaceous and ligulate, slightly
undulate at the margin, with shallow constrictions at intervals of about 2 em. ; where
a dichotomy occurs the branches are very close together, almost touching. The pro-
liferations along the margin are often numerous, and are usually quite small, whilst
those at the apex are sometimes as large as the primary frond; and where three or
four occur together, they give the plant a digitate appearance. In transverse section
the thallus is seen to be composed of two strata. Within are two to three rows of lax,
empty, polygonal, very thick-walled medullary cells, surrounded by a cortex of two to

three rows of minute flattened coloured cells (fig. 22). The eystocarps are marginal,

MARINE ALG. 13

either sessile or very shortly pedicellate, ovoid and bluntly rostrate. The pericarp is
composed of six or more rows of cells in vertical series.

Its nearest ally is P. interrupta, which it somewhat resembles in external form ;
but it differs from that species in having simpler and more lonely dichotomous
branching (being very rarely or never palmate), and the apices of the branches ligulate
and not reniform or rotundate. The thallus is not moniliform or torulose, but merely
opposito-sinuate. P. interrupta is more shortly dichotomous, and often has a triangular
expansion below its dichotomy, and palmate branching. The constrictions, too, are
often reduced to almost stalk-like thinness, which is not the case in P. antaretica.
P. interrupta is an Arctic species, and P. antarctica appears to be its Antarctic
congener. Possibly they are antipodal polar descendants from a common ancestor.

P. Brodiei J. Ag. differs in its long stipes cuneately expanded into a more or less
palmate frond, and is apparently the Arctic congener of the Antarctic P. cuneifolia,
which has shorter stipes, broader less-lobed frond, and broader shorter lobes with
shallower sinus.

13. SPONGOCLONIUM ORTHOCLADUM.
(Plate IV., figs. 23-25.)

Frons 8 cm. alta dense fruticulosa, axi centrali erecto tereti rhizoidibus haud
corticato ramulis ascendentibus velato, quoquoversum ramoso, ramis cauli similibus
ramulis ultimis longis erecto-patentibus simplicibus strictis subulatis, articulis diametro
sesquilongioribus, articulo basali nune nudo nune procarpium intra ramellorum
minutorum fasciculum emittente. Tetrasporangia ignota.

Cape Adare, January 9, 1902.

This is a densely bushy plant (fig. 23) of moderate size, about 8 cm. high without the
basal attachment and without tetraspores, but bearing young procarpia with tricho-
gynes (figs. 25a, 25b), and so thickly infested with diatoms that it is difficult to obtain
a clear view of its ramification. S. orthocladum is remarkable for its long straight
subulate ultimate branchlets (fig. 24), and differs in this respect from all the fruticulose
Callithamnioid species which we have seen. Its nearest ally is found in certain
states of S. hirtum [ Callithamnion hirtum Hook. f. and Harv. in Flora Antarctica, IT.
(1847), pl. Ixxviil., figs. 3 and 4], a plant recorded from the Auckland Islands and New
Zealand. The typical plant, it is true, differs inter alia in having ultimate pinne
consisting of a flexuose rachis bearing sub-distichous incurved obtuse ramelli. There is,
however, in the British Museum a specimen from Cook’s Straits, New Zealand, collected
by David Lyall and named by Harvey, which, though normal in most respects, yet has
a few branches which break up into long, straight, subulate ramelf like those of
our plant.

14 ANTONY GEPP AND ETHEL S. GEPP.

EXPLANATION OF PLATES I—IV.

PLATE I.

Lessonia grandifolia nob. Figs. 1a, 16. Mature fronds, showing flattened stipes dichotomously
branched and usually twisted, bearing long, simple, flat fronds with undulate margins and broken apex ;
jis natural size. Fig. 2. Three very young plants attached to a branch of Desmarestia harveyana, and
exhibiting even at this early stage almost as much branching as is found in a mature plant; natural size.
Fig. 3a. Transverse section (diagrammatic, and showing no cell-structure) of stipes at base of fig. la,
showing concavo-convex form and rounded-obtuse margins; natural size. Fig. 3b. Transverse section
of stipes, being the top of the cut branch on the left of fig. 1b, and showing two acute margins and
a long, light-coloured intra-medullary band; natural size. Fig. 3c. Portion of same (about two-thirds
of its width), showing that the intra-medullary band is composed of the cross-sections of scattered
trumpet-hyphex ; the bulk of the section consists of medulla, limited on the outside by the indistinct
subcortex and the pigmented cortical stratum. (x 10.) Fig. 4. The same in longitudinal section ; the
medulla here is also indicated by the trumpet-hyphi, which appear as longitudinal streaks. (x 10.)

PLATE II.

Lessonia grandifolia (continued). Fig. 5a. Transverse section of mature lamina, representing one-
half only of its thickness, and showing on the left the short, vertical rows of pigmented cortical cells ;
beneath this is the subcortical stratum of about 2 rows of rotundate cells, which are twice as large as the
cortical cells and pass into the closely packed hyphe which form the outermost portion of the medulla
and appear here as round cells, but are shown to be hyphe in longitudinal section (compare fig. 7) ;
these hyaline hyphe become more and more separated towards the middle of the medulla, and run in
various directions through the gelatinoid matrix, and among them are shown a few ensheathed trumpet-
hyphe. (x 110.) Fig. 5b. Small portion of similar section, showing four trumpet-hyphe with their
sheaths of small cells and a few of the ordinary hyaline hyphe of the medulla. (Xx 450.) Fig. 6.
Transverse section through a very young lamina (as in fig. 2), showing a monostromatic cortex of
eranular coloured cells, a subcortical layer of 1-2 rows of large clear cells, and a medulla composed of a
few lax hyphx and one ensheathed trumpet-hypha. (x 450.) Fig. 7. Longitudinal section of mature
lamina representing half the thickness of the frond, and showing (as in fig. 5) the short vertical rows of
pigmented cortical cells ; the subcortex of 1-2 rows of rotundate cells twice as large as the cortical cells ;
and the medullary hyphe densely packed on the outer side and becoming gradually more laxly arranged
towards the interior, where, interspersed among them, are portions of three trumpet-hyphe in longitudinal
and one in transverse section. (x 110.) Fig. 8. Longitudinal section of very young frond, showing the
three strata already described for fig. 6. (x 340.) Fig. 9. Portion of medulla of stipes in longitudinal
section, showing a trumpet-hypha with its sheath of small cells and its wall densely marked with transverse
striz ; the cell-contents have contracted into a narrow strand along the axis of the cell. (x 450.)

Lessonia simulans sp.nov. Fig. 10. Outer part of a longitudinal section of stipes, representing the
external part of the medulla, which is composed of densely packed straight hyphe ; these latter externally
pass gradually into a pluristromatic subcortex of large round and transversely oblong cells which, running
radially outwards towards the periphery, subdivide more and more, forming a cortex composed of short

vertical rows of small quadrate cells. (x 110.)

PLATE IIl.

Desmarestia harveyana nob. Fig. 11. Small portion of a large plant, showing that the ramification
is always opposite ; natural size. Fig. 12. Apex of an ultimate branchlet in surface view, showing that
the cortex is continued to the very apex of the axial filament. (x 110.) Fig. 13a. Transverse section
of a mature stem, showing its compressed form ; in the centre is the ensheathed primary axial filament and,

ee

MARINE ALGAl. UD

to the right and left, some fifteen secondary similar filaments each in 1ts sheath of small cells. (x 25.)
Fig. 13). Part of the same, showing an ensheathed secondary filament apparently containing tyloses ; the
large cavity on the left is merely an ordinary cell of the thallus. (x 450.) Fig. 14a. Longitudinal
section of mature stem, showing the primary axiai filament with its branches (secondary filaments) and
their anastomoses; all these filaments are distantly articulated. (x 4.) Fig. 144. Small portion of
longitudinal section of stem, showing a secondary filament faintly indicated within its sheath of small
cells. (x 340.) Fig. 15. Transverse section of an ultimate ramulus showing the primary axial filament
in the centre. (x 110.)

Desmarestia viridis Lam. var. distans, Hook. and Hary. Fig. 16. Transverse section of stem, showing
a denser medullary tissue in which the primary axial filament has become obliterated. (x 25.)

Gracilaria dumontioides nob. Fig. 17. Antarctic specimen consisting of numerous cuneato-linear
proliferations arising from a fragment of an old frond ; natural size.

PLATE IV.

Gracilaria dumontioides—(continued). Fig. 18. Transverse section of the above-mentioned fragment
of old frond near its margin, where the cortex becomes thicker and polystromatic ; the internal tissue
consists of large cells permanently flattened in drying the plant. (x 400.) Fig. 19. Monostromatic
cortex in surface view. (x 650.) Fig. 20. Arctic plant named by Harvey Halosaccion dumontioides,
collected by Dr. Lyall in lat. 76° N., and preserved in the British Museum ; its proliferations are very
long and simply linear ; natural size.

Phyllophora antarctica nob. Fig. 21a. Plant bearing marginal cystocarps; natural size. Fig. 210.
Sterile plant bearing large and small proliferations; natural size. Fig. 22. Longitudinal section of
cystocarpic branch, containing a compound cystocarpic nucleus. (x 80.)

Spongoclonium orthocladum sp. nov. Fig. 23. Part of plant; natural size. Fig. 24. Rather
diagrammatic representation of apical part of a branch, showing the long, straight, subulate ramelli.
(x 35.) Figs. 25a, 25b. Young procarpia with trichogyne.

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MARINE ALGA.
II.-CORALLINACEA.

sy M. Foss.
LITHOTHAMNION COULMANICUM.

Amone the Natural History collections made in the Antarctic regions by the
‘Discovery ’ Expedition are some specimens of a calcareous alga, which has been
kindly sent me for determination. They proved to represent a species new to science
belonging to the genus Lithothamnion, which I shall now describe. The species has
been shortly mentioned in “ Det Kgl. norske Videnskabers Selskabs Aarsberetning ”
for 1904, p. 16 (Trondhjem, 1905), under the name of

LITHOTHAMNION COULMANICUM Fost.
The plant forms incrustations on pebbles. The crust is closely adherent to the
substratum when young, but when older it is here and there rather easily detached,

LITHOTHAMNION COULMANICUM Fost. Nar. SIZE.

particularly when attacked by animals or when covering extraneous objects. It is
thin, in the specimens brought home the thickness not exceeding 800, frequently
being less, or about 300n. The shape of young crusts is frequently more or less
irregular, but now and then almost circular, and so also when older, but then the plant
sometimes fully surrounds the substratum. It is sometimes indistinct concentric
zonate, and the edge is crenulate or irregular. Several crusts are often found on the
same substratum. They may run into each other, in some cases not showing any
visible mark where the joining takes place, in others here and there forming slightly
elevated ridges. The nature of the surface is determined by that of the substratum.
If this is smooth the crust is also smooth, and shines slightly when young. Older

9
VOL. III, aN

2 M. FOSLIE.

crusts often become a little uneven and finely rugged on the surface by growing over
small extraneous objects. Besides, in most of the specimens collected the surface of
the crust is somewhat rubbed, probably owing to the friction of the water by a rather
strong current. A similar appearance is often to be seen in northern Lithothamnaa,
particularly in sounds where the tides run strongly.

In a vertical section of the crust the basal hypothallic layer is distinctly, but not
strongly, developed, and the convergence of the lower anticlines of this layer towards
the substratum is very feeble or wanting. The cells are 12-18 long and 4—7p
broad. In the perithallic layer there is no stratification to be seen. The cells are here
partly squarish, often with rounded corners, 5-8 in diameter, partly and more
frequently vertically elongated, and 8-12 long, with a breadth of 6-8. Here and
there are to be seen cells with the longest diameter in the vertical direction, always,
however, in very small numbers in proportion to the squarish or vertically elongated
ones. The cell-walls are frequently rather thick.

As regards the organs of reproduction, the cystocarpic conceptacles are somewhat
crowded, subhemispheric-conical, but not quite superficial, as is frequently the case in
this genus, 300-350 or up to 400m in diameter, when seen from the surface. They
have been found only in one specimen, and most of them are in a state of decomposition.
In a few other specimens conceptacles of sporangia occur, They are in some cases
rather scattered here and there in the crust, in others somewhat crowded, convex, and
but little prominent, often when older almost disc-shaped, 300-400, in diameter seen
from above. The roof is intersected with about thirty to forty muciferous canals, which
are crowded in the central portions. The sporangia are two-parted, 90-120 long
and 40-50. broad. These organs were ripe in the latter half of January. However,
the greatest number of conceptacles observed were dissolved, leaving a shallow hole
or a cup-shaped scar, which later on becomes effaced by new-formed tissue. Once I
met with overgrown conceptacles in the thickest part of a crust, showing that these
organs may become fully dissolved only in the thinner and rather young specimens.

The present species stands nearest to Lithothamnion magellanicum, the latter,
however, being a coarser plant with, as a rule, larger and more prominent conceptacles
of sporangia and frequently larger cells. Besides, the sporangia are always four-
parted (tetrasporic) in L. magellanicum. On the other hand, the species in question in
some respects reminds one of the Arctic species Lithothamnion leave. Sterile specimens
can on a superficial examination easily be confounded with Lithophyllum decipiens.

This is the first species known from the Antaretic regions bearing two-parted
(bisporic) sporangia. Such were hitherto only known in some species of the genus in
question from the Arctic regions.

The plant was collected off Cape Wadsworth on Coulman Island, near South
Victoria Land, about 73° 30'S., 170° W. Here it was picked up from a depth of
ig fms. It seems to have been pretty plentiful, as some sixteen pebbles with
incrustations of the species were collected.

Ves CL.

Par J. CARDOT.

(2 Planches.)

PRESQUE toutes les mousses antarctiques connues jusqu ici provenaient de l’archipel de
Graham et des iles voisines, c’est-a-dire de cette partie de | Antarctide située au sud de
YAmérique, et comprise entre le 60° et le 65°™° paralléles. Les especes rapportées
de la Terre Victoria par l’expédition de la ‘ Discovery,’ bien que peu nombreuses,
présentent done beaucoup d'intérét, non seulement parce quelles nous yiennent d'une
région dont nous ne connaissions absolument rien jusqu’alors au point de vue botanique,
mais aussi parce qu’elles sont actuellement les espéces les plus australes connues, ayant
été récoltées entre 77° et 78° de latitude: Sud.

Il est fort probable qu’elles constituent, avec quelques Lichens, les derniers et
chétifs représentants de toute végétation terrestre dans la direction du Pole austral.
Si lon réfléchit que, d’apres les observations thermométriques faites au port d’hivernage
de la ‘ Discovery,’ par 77° 50’ lat. 8., de février 1902 a février 1904, la température
moyenne des deux mois les plus chauds, décembre et janvier, est de 3*80° C. au dessous
de zéro (= 24°95° F.); que le maximum observé, en décembre 1903, a été de 5°55° C.
au dessus de zéro (= 42 F.), mais que, méme pendant ces deux mois d’été, le thermo-
métre est plusieurs fois descendu en dessous de—10° C., et qu’en janvier 1904, il a
marqué—15°55°C. (= 4 F.), on peut étre surpris qu'il soit encore possible a des végétaux
dune organisation aussi délicate et relativement aussi compliquée que les mousses de
se développer et de vivre dans de semblables conditions climatériques.

La plupart portent d’ailleurs les traces de l’Apre lutte qu’elles soutiennent pour
Yexistence. Toutes forment des gazons extrémement compacts, afin de pouvoir résister
4 la pression des épaisses couches de neige qui les recouvrent pendant les longs mois
@hiver. Le Bryum argenteum, espece cosmopolite, se présente ici sous un aspect
tellement rabougri que les plus longues tiges que j’ai mesurées ne dépassaient pas une
hauteur de 3 millimétres, et que les plus grandes feuilles atteignaient seulement 0°35
millim. Le Brywm algens, dont les touffes, souvent & demi noyées dans la boue
glaciaire, peuvent atteindre une profondeur de 6 centimétres, présente fréquemment des
tiges d’un aspect malade, offrant des parties presque complétement dénudées ; sa nervure
s’écarte du type caractéristique du genre par l’absence des stéréides, et ses fleurs ren-
ferment parfois des organes imparfaits, qui semblent étre des archégones mal conformés.

2N 2

2 J. CARDOT.

Les tiges du Ceratodon purpureus émettent souvent des innovations gréles, garnies
de feuilles déformées. Dans le Sarconeurum glaciale, il est presque impossible de
trouver une feuille adulte entiére : toutes sont brisées vers leur tiers supérieur, la pointe
ainsi détachée servant fort probablement 4 la reproduction de Tespece. Aucune des
sept mousses rapportées par la ‘Discovery’ ne présente diailleurs de sporogone
développé ou en voie de développement; ce n’est vraisemblablement que dans des
circonstances tres exceptionnelles que l'une ou l'autre peut arriver & murir une capsule.

Un autre intérét de la petite collection de mousses qui fait objet de cette étude
est de nous montrer que, comme on devait d’ailleurs s’y attendre, la flore polaire
antarctique est probablement tres uniforme, puisque sur sept especes récoltées a la Terre
Victoria, cing (dont trois spéciales & la région antarctique) sont déja connues de
l’archipel de Graham et du détroit de Gerlache.

Voici la liste et la position géographique des localités, avec Vindication des espéeces
fournies par chacune delles :

I. Granite Harbour, lat. 8. 77°, long. E. 160°. Jan. 20, 1902.

Ceratodon purpureus Brid. forma.
Didymodon gelidus Card. sp. nova.
Bryum amblyolepis Card.

3 alyens Card. sp. nova.

II. Mount Terror, lat. 8. 78°, long. E. 169°. Jan. 22, 1902.

Sarconeurum glaciale (Hook. fil. et Wils.) Card. et Bryhn.
Bryum argenteum Lu.

III. ‘ Discovery’ W.Q., lat. 8. 78°, long. E. 176°. Dec. 1903.
Sarconeurum glaciale (Hook. fil. et Wils.) Card. et Bryhn.
IV. McMurdo Sound (lat. 8. 77°-78°, long. E. 166°), islet in old ice. Dee. 1903.

Bryum argenteum U.
alyens Card. sp. nova.
a antarcticum Hook. fil. et Wils.

V. Cape Royds, at the foot of Mount Erebus, lat. S. 77°, long. E. 166°. Jan. 11,
1904.

”

Bryum argentewm L.
Les récoltes de la ‘Discovery’ portent & 51 le chiffre des especes de mousses
actuellement constatées dans la région antaretique proprement dite.

DITRICHACEAE.
CERATODON PURPUREUS.

C. purpureus Brid., Bryol. univ. I, p. 480 (1826).

Granite Harbour, Jan. 20, 1902; ster.

Forme en gazons denses, ordinairement assez profonds (4-5 centimétres), plus ou
moins encombrés de terre. Feuilles courtes, petites, trés variables, tant6t aigués, &

MUSCI. 3

nervure percurrente ou subexcurrente, tantdt obtuses, 4 nervure disparaissant sous le
sommet ; en outre, sur certains échantillons, les tiges se terminent par des innovations
geréles, garnies de feuilles écartées, tres molles, les supérieures largement ovales, concaves,
brigvement acuminées, ou obtuses-arrondies et souvent cuculiées au sommet, et a
nervure disparaissant alors avant l’extrémité. Ces variations dans la forme des feuilles,
variations qui peuvent se rencontrer sur la méme tige, sont probablement dues i des
causes climatériques. I] existe dans la flore arctique une forme analogue: cest le
C. heterophyllus Kindb., de Vile St. Paul, dans la mer de Bering, dont les tiges émettent
des innovations gréles et allongées, garnies de feuilles obtuses; et Limpricht a décrit
aussi, sous le nom de var. obtusifolius, une forme des Alpes de Styrie qui a également
les feuilles obtuses et la nervure disparaissant avant le sommet (Laubmoose, I, p. 487).
—Pl. I, fig. 12 4 17.

POTTIACEA.

SARCONEURUM GLACTALE.

S. glaciale (Hook. fil. et Wils.) Card. et Bryhn, comb. nova.
Didymodon (?) glacialis Hook. fil. et Wils., Fl. antarct. IT, p. 408, tab. clii. fig. vi. (1847).
Sarconeurum antarcticum Bryhn, in Nyt Mag. f. Naturvidenskab, B. 40, H. III, pp. 204-207, tab. i.
et ii (1902). Z

Mount Terror, Jan. 22, 1902. ‘ Discovery’ W.Q., Dec. 1903; ster.

Cette curieuse mousse fut récoltée pour la premiére fois en 1843 par Sir Joseph
Hooker sur l’ile Cockburn (archipel de Graham), et décrite en 1847 dans le Vora anturetica,
par Hooker fils et Wilson, sous le nom de Didymodon (?) glacialis. Beaucoup plus tard,
en 1899, M. Borchgrevink la rapporta de la Terre de Geikie et de la Terre de Newnes ;
les échantillons furent communiqués & M. Bryhn, qui, en 1902, eréa pour eux le genre
Sarconeurum, et décrivit lespece sous le nom de S. antarcticum. Ayant pu comparer
entre eux des échantillons originaux de la plante récoltée par Hooker et de celle
recueillie par M. Borchgrevink, j’ai reconnu leur complete identité, et daccord avec
M. Bryhn, je substitue au nom de Sarconeurum antareticum celui de S. glaciale.

La densité des touffes de cette mousse est ordinairement remarquable ; mais l'un des
spécimens provenant de la station d’hivernage de la ‘ Discovery’ est particuliérement
curieux sous ce rapport: cest un petit gazon excessivement compact, profond de 15 a
20 millimétres, formé par les tiges tres serrées les unes contre les autres, et envahies
jusqu’au sommet par un feutre radiculaire brun trés abondant ; cette masse dense se
moule étroitement sur les débris de lave au milieu desquels elle vit, et dont elle
recouvre et entoure complétement quelques-uns des plus petits. Toutes les feuilles
adultes ont la pointe brisée; seules, les jeunes feuilles en voie de développement au
sommet des tiges sont entieres.

Lorganisation de cette plante semble adaptée d’une fagon remarquable aux dures
conditions climatériques au milieu desquelles elle est appelée & vivre: la densité
extraordinaire de ses touffes lui permet de supporter sans inconvénient la pression des

4 J. CARDOT.

masses de neige qui la recouvrent en hiver, et de résister victorieusement aux alterna-
tives de gel et de dégel auxquelles elle est exposée pendant le court été polaire, tandis
que la fragilité et le sectionnement spontané de l’extrémité de ses feuilles lui assurent
un mode de reproduction asexuée suppléant efficacement a la propagation par spores.

M. Bryhn a donné de cette espece une excellente description et de bonnes figures,
faisant bien ressortir les caracteres si particuliers de la nervure, qui se termine par une
pointe charnue, dilatée, formée de cellules trés riches en chlorophylle.

DIDYMODON GELIDUS.

Caulis gracilis, erectus, simplex vel parcissime ramosus, 3-6 millim. altus. Folia
remota, minuta, erecto-patentia, breviuscula, ovato-lanceolata, late acuminata, acuta
obtusulave, 0°7-0°8 millim. longa, 0°4—0°45 millim. lata, marginibus integris, tantum
in parte superiore papillis prominulis minute crenulatis, ubique planis vel superne parce
et anguste revolutis, costa dorso rotundata, basi 50-60 p crassa, pro more lutescente,
sub summo apice evanida vel subpercurrente, cellulis inferioribus rectangulis vel sub-
quadratis, levibus, pellucidis, mediis et superioribus minutis, obscurulis, subquadratis,
papillosis. Czetera desiderantur.

Granite Harbour, Jan. 20, 1902; ster.

Je nai trouvé que quelques brins de cette espece, mélangés parmi les autres
mousses. La tige est pourvue d’un faisceau axile bien distinct, ordinairement brun ;
les cellules corticales sont plus petites que les cellules sous-jacentes, mais peu différentes
dailleurs. Sur une coupe transversale, la nervure présente une couche épidermique
ventrale, formée de cellules analogues 4 celles du limbe, en dessous de laquelle on trouve
des cellules un peu plus grandes, en une ou deux couches, recouvertes sur la face
dorsale par deux ou trois assises de cellules plus petites, 4 parois épaissies et jaundtres
(substéréides). I] n’y a ni vraies stéréides, ni sténocystes. Par ces caractéres
anatomiques, de méme que par la forme et le tissu des feuilles, cette mousse me parait
devoir prendre place dans le genre Didymodon. On peut la comparer au D. luridus
Hornsch., dont elle différe par ses faibles dimensions, ses tiges plus gréles, et ses feuilles
i bords plans ou tres peu révolutés, et & tissu basilaire plus lache, formé de cellules
rectangulaires, lisses, pellucides, subhyalines.—PI. I. figs. 1 & 11.

BRYACEZ.

BRYUM ARGENTEUM.
B. argenteum L., Sp. plant. p. 1120 (1753).
Mount Terror, Jan. 22, 1902; islet in old ice, MacMurdo Sound, Dec. 10, 1903 ;
‘Discovery’ W.Q., Dec. 15, 1903 ; Cape Royds, Jan. 11, 1904; ster.
L’aspect de ces échantillons prouve que cette espece, qui jouit d’une dispersion

MUSCTI. 5

cosmopolite, se trouve ici dans des conditions tres défavorables : les tiges n’atteignent que
2 43 millimétres de haut, et les plus grandes feuilles mesurent seulement 0°35 millim.

BRYUM AMBLYOLEPIS.

B. amblyolepis Card. in Rev. bryol. xxvii, p. 45 (1900), et Result. Voyage ‘ Belgica,’ Mousses, p. 37, pl.
xi, fig, 1 4 11 (4901).

Granite Harbour, Jan. 20, 1902; ster.

Beaux et nombreux échantillons, formant des gazons étendus, veloutés. On
trouve ca et la des feuilles qui se rapprochent beaucoup de celles du B. argenteum,
mais l’aspect général de la plante reste différent, et la plupart des feuilles sont obtuses
ou subapiculées.

Cette espece n’était encore connue que du détroit de Gerlache.

BrRYUM ANTARCTICUM.

B. antarcticum Hook. fil. et Wils., Fl. antarct. If, p. 414 (1847).

Islet in old ice, MacMurdo Sound, Dec. 1903 ; ster.

Découverte par Hooker, & Vile Cockburn, cette espece a été retrouvée aux iles
Paulet et Seymour par M. C. Skoftsberg, botaniste de lexpédition antarctique
suédoise.

BRYUM ALGENS.

Cespites densissimi, valde cohzerentes, intus fusco-rubelli, superne viridi-lutescentes,
terra lutosa saepe obruti. Caulis erectus, ruber, parce radiculosus, nunc brevissimus,
simplex, 3-10 millim. altus, nune elongatus, usque 6 centim. longus, dichotome divisus,
ramis erectis, plus minus clavatis. Folia nune apice caulis et ramorum glomerata,
nune subequaliter conferta, erecta vel patenti-erecta, inferiora minora, saepe valde
remota, 1°6—2 millim. longa, 0°6-0°9 millim. lata, lanceolata, marginibus planis,
superiora vel comalia majora, concava, polymorpha, late breviterque ovata, oblonga vel
elongato-lanceolata, 1°7—3 millim. longa, 0°7—1 millim. lata, sat breviter vel longius-
cule acuminata, marginibus integris, plus minus longe revolutis, interdum planis, costa
basi pro more rubella, 100-150 crassa, in cuspidem levem, viridem breviuscule vel
longiuseule excurrente, cellulis inferioribus teneris, subrectangulis, hyalinis rubellisve,
mediis et superioribus subrhomboidalibus, oblongis, chlorophyllosis, marginalibus
angustioribus longioribusque, sed limbum distinctum non efformantibus. Inflorescentia
monoica, forsan polyoica. Fructus desideratur.

Granite Harbour, Jan. 20, 1902, ¢. flor. ; islet in old ice, MacMurdo Sound, Dee.
L903"; ster.

Cette espece nouvelle ressemble beaucoup au 2. inconnewum Card., du deétroit de
Gerlache, mais elle s’en distingue par ses gazons tres cohérents et compacts, ses tiges
plus gréles, ses feuilles de forme variable, ordinairement agglomérées en touffes au

6 J. CARDOT.

sommet des tiges et des rameaux, a bords moins longuement et moins réguliérement
révolutés, souvent presque plans.

Sur une section transversale, la nervure présente ordinairement un groupe de
stenocystes en dessous de Tassise d’eurycystes ; mais les stéréides font défaut; elles
sont remplacées par des cellules plus petites que les éléments épidermiques, mais a
lumen cependant assez large et & parois peu €paissies. Dans deux espéces du détroit de
Gerlache, B. inconnexum Card. et B. Gerlachei Card., la nervure est également dépour-
vue de vraies stéréides, et ne présente que des substéréides, et il est tres remarquable
qu'une espece arctique récemment décrite, le B. languidum Nag., de Vile Disco, sur la
céte occidentale du Groenland, posstde une nervure organisée exactement comme celle
du B. algens.* Tl est probable que cette altération de la structure typique de la
nervure dans le genre Bryum est due 4 Vinfluence du climat polaire.

Les échantillons de B. algens de Granite Harbour m’ont présenté trois sortes de
flears: les unes males, contenant un grand nombre d’anthéridies, entremélées de
paraphyses trés nombreuses, plus longues, hyalines, légerement atténuées au sommet ;
les autres femelles, renfermant des archégones plus ou moins parfaits, entourés de
paraphyses plus courtes qu’eux ; enfin, des fleurs renfermant a la fois des anthéridies et
dautres organes mal développés, mais qui paraissent étre des archégones imparfaits,
plus ou moins atrophiés ; lespece serait done polyoique. Ce caractere la rapprocherait
du B. languidum Hag., dont il vient d’étre question, et auquel elle ressemble aussi par
la forme et le tissu des feuilles, mais qui s’en distingue dailleurs par ses gazons laches,
peu cohérents, par ses feuilles distinctement marginées, et par sa nervure moins large
(diam. 60-70 y).—PI. IT.

EXPLICATION DES PLANCHES.
PLANCHE I.

Fig. 1 & 11. Didymodon gelidus Card.—1, plante, grandeur naturelle. 2, une tige x 3. 3, partie
dune section transversale de la tige x 360. 4, 5, 6, 7, feuilles x 35. 8, tissu de la partie basilaire d’une
feuille x 360. 9, tissu de la partie moyenne d’une feuille x 360. 10, tissu du sommet d’une feuille
x 360. 11, section transversale de la nervure X 360.

Fig. 12417. Ceratodon purpureus Brid. forma.—t2, 13, 14, 15, 16, 17, feuilles de formes diverses
x35.

PLANCHE II.

Bryum alyens Card.—1, 2, plantes, grandeur naturelle. 8, sommet d'une tige x 3. 4, 5, 6, 7, feuilles
inférieures des innovations x 17. 8, 9, 10, 11, 12, 13, 14, 15, feuilles moyennes et supérieures des innova-
tions X17. 16, 17, sommet de deux feuilles x 43. 18, tissu de la partie basilaire dune feuille x 184.
19, tissu de la partie moyenne d’une feuille x 184. 20, tissu de la pointe d’une feuille x 184. 21, section
transversale de la nervure x 360.

* Cfr. Hagen et Porsild, Meddel. om Groenl., XXVI. p. 463, pl. XV.

LONDON ; PRINTED BY- WILLIAM CLOWES AND SONS, LIMITED, DUKE STREET, STAMFORD STREKT, 8,E., AND GREAT WINDMILL STREET, W.

Plate I.

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