qQL 444 D3A35 INVZ

ALCOCK

AN ACCOUNT OF THE DEEP-SEA

BRACHYURA COLLECTED BY THE ROYAL INDIAN MARINE SURVEY SHIP INVESTIGATOR

\

oC 444 D3A35 Invert. Zool.

AN ACCOUNT

OF THE

DEEP-SEA BRACHYURA

COLLECTED BY THE

ROYAL INDIAN MARINE SURVEY SHIP

INVESTIGATOR

BY

oom COCK, M.B., C.M.Z.S.,

INDIAN MEDICAL SERVICE, SUPERINTENDENT OF THE INDIAN MUSEUM AND PROFESSOR OF ZOOLOGY

Fi Gir Se,

IN THE MEDICAL COLLEGE, CALCUTTA; FORMERLY NATURALIST TO THE MARINE SURVEY.

CALCUTTA: PRINTED BY ORDER OF THE TRUSTEES OF .THE INDIAN MUSEU {

1899,

x of 2H oy = Ga

PREFATORY NOTE.

A good many reports, more or less of a preliminary character, have been published in various Journals since 1885, relative to the zoological work of the Marine Survey of India, under the title of Natural History Notes from H. M. Indian Marine Surveying Steamer ‘Investigator, and these unofficial reports have been supplemented since 1892 by the official series—published under the author- ity of the Director of the Indian Marine—of Illustrations of the Zoology of the Royal Indian Marine Survey Ship Investigator.’

The present volume contains an independent Report upon the Brachyurous Crustacea collected by the ‘Investigator,’ and it seems advisable to preface it with a short explanation (which has already been published in the Account of the Investigator Deep Sea Madreporaria) of the way in which the ship hecame connected with deep-sea exploration and with the Indian Museum.

In the year 1871 the Council of the Asiatic Society of Bengal appointed Dr. 'T. Oldham, Dr. F. Stoliezka and Mr. J. Wood-Mason to form a sub-committee to report upon the desirability of moving the Government of India to undertake deep-sea dredging in Indian waters.

The sub-committee drew up an elaborate JZemoztr on the subject, in which definite proposals for deep-sea dredging were embodied : this Memoir was submitted to Government, and a copy of it along with a copy of the letter with which it was forwarded, is published in the Proceedings of the Asiatic Society of Bengal for 1871.

The Government received the proposals of the Council of the Asiatic Society with cordial approval : it gave a small grant in aid of carrying them into immediate effect,» and when, in 1874, the present Marine Survey Department was established, it sanctioned the appointment, upon the staff of the Survey, of a Surgeon-Naturalist—an appointment that had also been strongly advocated by the organizer and first head of the Department, Commander Dundas Taylor, I. N.

But in the early days of the Survey (1874-1881) neither machinery nor vessels capable of deep- sea research were available, so that Surgeon (now Lieutenant-Colonel) J. Armstrong, I.M.S., the first Surgeon-Naturalist of the Department, had to report that it was “quite impossible to carry into execution the scheme of deep-sea dredging originally proposed by the Council of the Asiatic Society of “Bengal,” and had to confine himself to the Zoology of the shallow-water and littoral, although he did

manage to dredge in water as deep as 100 fathoms.

However, in 1876, when it had been decided to construct a special vessel for the accommodation of the Marine Survey, the Council of the Asiatic Society again addressed the Government of India, and asked that provision for deep-sea dredging might not be forgotten in the plans for the new vessel. In reply the Government authorized the Council of the Society to confer with the Dockyard authorities on the subject of such equipment.

The Council thereupon appointed a sub-committee, consisting of Dr. John Anderson, then Super- intendent of the Indian Museum, and Messrs. J. Wood-Mason (then Deputy Superintendent of the Indian Museum), W. T. Blanford, H. F. Blanford, and H. B. Medlicott, for the purpose of advising the Dockyard authorities in this direction.

The result of this and other measures was that when, in 1881, the new vessel Investigator was ready for sea, she was properly provided with the means of undertaking deep-sea research as opportu- nity should occur.

ii Before this, however, Dr. Armstrong had left the Survey, and it was not until the end of the year 1884, when Commander A. Carpenter, R. N., was appointed to the command of the Investigator,’ and Surgeon (now Major) G. M. J. Giles, LMLS., to the post of Surgeon-Naturalist, that deep-sea dredging became a recognized, if subordinate, branch of the ship’s routine. Since 1885 the Zoological collections made by the Investigator’ have been year by year accumu-

lating in the Indian Museum, where, in accordance with the recommendations of the Council of the Asiatic Society of Bengal, they have been deposited.

It must not, however, be supposed that deep-sea dredging occupies a very large part of the attention of the officers of the Survey ; since, as a rule, it is only possible when the ship is proceeding to and returning from her systematic surveys of the shores and shallows. It is rarely indeed that as many as twenty deep-sea hauls are made in one year.

From October 1888, when regular records began to be kept, up to the present time, 113 more or less successful hauls have been made in depths of over a hundred fathoms (100-1997 fms.) : of these

71 have been under the superintendence of Captain A. R. S. Anderson, I.M.S., who has been Surgeon- Naturalist since 1893.

As regards the Investigator’ herself, she is a paddle-steamer of 580 tons, and for a few facts as

to her history and equipment I may refer to a paper in the Secentific Memoirs of the Medical Officers of the Army of India for 1898.

With regard to the contents of the present Report on the Brachyura, I may mention that the

species that are not here described for the first time have already been noticed in the following papers, relating to the Indian Fauna :—

J. Woop-Mason in Ann. Mag. Nat. Hist., May, 1877, p. 422: in Proc. As. Soc. Bengal, August, 1885: in Journ. As. Soc. Bengal, Vol. LVI, pt. 2, 1887, p. 206, pl. i: and in Ann. Mag. Nat. Hist., March, 1891, pp. 258-270.

A. Atcock in Ann. Mag. Nat. Hist., May, 1894, pp. 400-409 : and in Materials for a Carcino- logical Fauna of India in Journ. As. Soc. Bengal, Vols. LXIV, LXV and LXVII, pt. 2, 1895, 1896, 1898.

A. Atcock and A. R. S. AnpERson in Journ. As. Soc. Bengal, Vol. LXIII, pt. 2, 1894, pp. 175-185: and in Ann. Mag. Nat. Hist., Jan., 1899, pp. 5-14.

A. R. S. Anprrson in Journ. As. Soc. Bengal, Vol. LXV, pt. 2, 1896, pp. 102-106,

ILLUSTRATIONS OF THE ZooLoay oF THE R. I. M. 8. “Investigator” by Wood-Mason, Aleock, and Anderson, Crustacea, pl. v. xiv. xv. XVi. XVil. XVili. XIX. XX. XX]. XXI1. XXI1. XXIV. XXV. (XXXVi. XXXvVil. xxxix. xl. in the press).

The illustrations, like those of the Account of the Deep Sea Madreporaria, have been drawn here

by Baboos Abhoya Churn Chowdry and Shib Chunder Mondul, and reproduced in collotype by Messrs. Taylor and Francis of London.

A. ALCOCK, Major, I.M.S., Superintendent of the Indian Museum.

i

Page

67.

68.

CORRIGENDA. Homola andamanica. Add Illustrations of the Zoology of the Investigator, Crustacea, pl, xl. fig. 1. For Dynomene margarita” read Acanthodromia margarita.

After the description of Physacheus tonsor insert Grypachwus hyalinus (see Addenda, p. 83).

After the description of Sphenocarcinus cuneus insert Sphenocarcinus aurore (see Addenda, p. 84).

For ‘‘ Corysromea read Cycnromprora, Family Corystide.

After the description of Orphnoxunthus microps insert Guryon and Geryon ajjinis (see Addenda, pp. 84, 85).

After Family Portunidx add Subfamily Lupine. And for Gontosoma” read CHARYB- pis (GoNIoHELLENUS). And for Goniosoma hoplites” read Charybdis (Goniohel- lenus) hoplites.

For Subfamily Carcinine read Subfamily Portunine.

N.B—1. The species added are from the collections made in the season 1898-99, and were

received after the manuscript had been printed. 2. The corrections rest upon an examination of

all the Cyclometopa and Dromiacea in the Indian Museum and are justified in my Materials for a Carcinological Fauna of India, No. 4, The Brachyura Cyclometopa, and No. 5, The Brachyura Primigenia (Journal Asiatic Society Bengal, Part II. 1899). 3. Owing to unavoidable delay in

issuing this volume the Investigator Illustrations referred to as “in preparation or “in the press,” are now ready and about to be distributed.

An Account of the Deep-sea Brachyura collected by the Royal Indian Marine Survey Ship Investigator.”—By A. Atcocx, M.B., C.M.Z.S., F.G.S., Superinten- dent of the Indian Museum and Professor of Zoology in the Medical College of Calcutta : formerly Surgeon-Naturalist to the Indian Marine Survey.

With two exceptions—namely, a Homola that is very possibly identical with the deep-sea Homola orientalis of Henderson and a singular species of Dynomene —the Brachyura here described came from depths over 100 fathoms.

The species number 53, and belong to 38 genera, and they have been collected by the ‘Investigator’ during the last fourteen years (1885-1898). Specimens of all, including the types of new species, are in the Indian Museum.

Of these 53 species only the following five are known from other seas :— Ethusina gracilipes Miers, Cyrtomaia Suhimi Miers, Platymaia Wyville-Thomsoni Miers, Oxyplewrodon Stimpsonti Miers, Scyramathia pulchra Miers. These five are “Challenger” species from the seas of the Hast Indian Archipelago, but Ethusina gracilipes has also, according to Faxon, been taken off the Pacific coast of the Panama region.

To those who expect a faunal list to furnish forth some theory of geogra- phical distribution, our lst will appear disappointing.

If, however, we regard genera and not species, the list discloses some suggestive affinities between the Brachyuran fauna of these Seas and of certain parts of the Atlantic area. These affinities may, of course, be taken as merely confirmatory of current views as to the unity of the Deep-sea Fauna; but, seeing that the Brachyura are not generally considered to belong to the true deep-sea (abyssal) fauna, I think it equally probable that they may afford evidence of a former open connexion between the seas in question.

In an Account of the Investigator Deep-sea Madreporaria (pp. 2-10) I have discussed this matter at some length, so that here I need speak only of the supplementary evidence that the deep-sea Brachyura appear to furnish of this connexion.

Of the 38 genera that are at present known to compose the Brachyuran fauna of the Indian depths the following 21 are also known to occur in other seas :—Homola, Dynomene, Calappa, Mursia, Randallia, Ethusa, Hthusina, Lyrei- dus, Echinoplax, Cyrtomaia, Platymaia, Sphenocarcinus, Oxypleurodon, Scyramathia, Maia, Trichopeltariwm, Trachycarcinus, Goniosoma, Pilumnoplax, Careinoplax,

Pinnoteres.

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Homora. This genus, which is represented in India by three good species, was long regarded as characteristic of the Mediterranean. The Mediterranean species (H. barbata) is now known to occur in the West Indies and neighbouring coasts of N. America, and a form that is probably only a variety of it—described in the sequel as H. andamanica—has lately been taken in the Martaban end of the Andaman Sea at 79—90 fms. This H. andamanica may possibly be the same as Henderson’s H. orientalis from the Banda and Sulu Seas.

Furthermore, of the 3 Indian species of Homola, one—described in the sequel as H. profundorum—is closely related to the Mediterranean H. Cuvieri in Wood-Mason’s genus (preferably subgenus) Pavomola.

DyNnoMENE ranges across the whole Indo-Pacific from Mauritius to California.

Caxappa is a shallow-water genus: the species are distributed all over the Indo-Pacific, from Africa to California, and are also represented in the West Indies, the Mediterranean, and on the west coast of Africa as far as the Cape.

Mursta. The geographical distribution is not remarkably different from that of Calappa, except that it does not occur in the Mediterranean.

RaNDALLIA seems to be confined to the Indo-Pacific.

Erxusa, of which Eruusiya is a subgenus, extends from the West Indies and neighbouring coasts of N. America to the Azores and the Mediterranean. In the Indo-Pacific it extends from the Arabian Sea to Japan and the Philip- pines, to Fiji, and to California and the Pacific coast of Panama.

Lyreipus. One species is common in Indian waters at 200-400 fathoms : another belongs to the North American Atlantic slopes at 100 fathoms: a third species belongs to the Japanese fauna, and also extends into Australasian waters.

Ecutnopiax, Cyrromaia and PiatyMatA appear to be confined to the Indo- Pacific. But I do not think that Cyrtomaia is really different from Hchinoplaa, or that either should be separated from the Atlantic and Mediterranean Hrgasticus of A. Milne-Edwards.

SPHENOCARCINUS, one species of which occurs in the Andaman Sea at 161-250 fathoms, is a genus originally discovered in the Caribbean Sea at 100 fathoms. A third species, however, has been described by Miss Rathbun from shallower water in the Gulf of California. Ozyplewrodon hardly differs from Sphenocarcinus.

ScyramatHia is a North-Atlantic genus (European, N. American and Carib- bean) that is well represented in Indian Seas. Other species are known from the Philippines and from the Galapagos.

Mara. In the time of H. Milne Edwards this was supposed to be a genus peculiar to the seas of Europe (Mediterranean, British Seas, North Sea). One

species is common to Japan and the Kast Indies, one has been described from Australasia, and recently two more have been added from the Oriental region.

Of the 2 Corystoid genera that occur in Indian deep waters :

TRICHOPELTARIUM is only known elsewhere from the Caribbean Sea, while the closely allied Tracnycarcints is from the Pacific slopes of Central America.

Gontosoma, PinumnopLax and CarcrnopLax may be regarded as shallow-water Indo-Pacific genera, Pilumnoplax occurring also in the South Atlantic.

Of the genera here referred to as peculiar (so far as is known) to Indian Seas, two require special notice in connexion with this question of geographical distribution.

The first of these is the Dromioid genus AracunopromiA. This is so extremely like Prof. A. Milne Edwards’ Homolodromia from the Caribbean Sea, that I should have taken it almost for the same species had not M. Milne Edwards stated that the form described by him has neither antennulary nor special orbital fossee. Our species has common antennulo-orbital fosse not essentially different from those of Dromia.

The second is BenrHocuascon, which is very intimately related to the Gulf of Mexican Bathynectes. The last named genus, however, is also known from the Eastern Pacific.

The Composition of the Brachyuran Fauna of the Indian Oligo-benthos.

This, so far as is known, is as follows :—

Catometopa 7 species, or 152 per cent. Cyclometopa (including Corystoidea) 8 ho Tam ae are Dromidea (Dromidx and Homolide) 9 te TROY Ge Oxystoma (including Raninide) 14 He ce yaks Oxyrhyncha 15 pepe SB ep ye

The large proportion of Oxyrhynchs and the small proportion of Cyclomet- opes and of Catometopes (due regard being paid to the relative proportions of these groups in their entirety) is interesting to those who do not accept the view that the Oxyrhynchs as a whole are the highest Crustacean developments.

The very large proportion, relative to the size of the group, of Dromidea is also of much interest.

The Bathymetric Range of the Indian Deep-sea Brachyura. Only one species—Hthusa investigatoris—has been dredged in 1200-1300 fathoms. The following three species occur between 800 and 1,000 fathoms :—

Hypsophrys superciliosa 740-931 fms. Ethusa desciscens 931 35 Ethusa gracilipes 836 7

The three following species occur between 500 and 800 fathoms :—

Paromolopsis Boast 597 fms. Ethusa indica 79); Scyramathia pulchra 561 ,,

The following 18 species occur between 400 and 500 fathoms.

ee (ee profundorum 430 fms. & a Hypsophrys lengipes 430 35 Arachnodromia Bafini 430 FA is ¢ Randallia pustulosa 406 x e Cymonomops glaucomma 405 7 © X Lyreidus Channeri 406 .; ( Physachaeus ctenurus 406 5 si | Cyrtomaia Suhmi 430, cs 4 Platymaia Wyville-Thomsoni 405 0 ) | Bnceephaloides Rivers-Andersoni 406 a UScyramathia Rivers-Andersoni 406-430 _,, E ee ee glaucus 430 £ 3 Benthochascon Hemingt 405 x ( Carcinoplax longipes 430 3 E | Pilumnoplax Sinclairi 430 5s aS) 4 Psopheticus stridulans 419 A 'S) | Hephthopelta lugubris 490 9 Pinnoteres abyssicola 430 *

Thus rather more than half the species of Indian deep-sea crabs have been taken only in depths between 400 and 100 fathoms. Moreover, a good many of the species that range into the greater depths mentioned above also occur

in shallower water.

On the other hand, with the single doubtful exception of Doclea ovis, we have no instance of a true shallow-water crab being taken so far out as the hundred-fathom line.

The majority of the species here described have already been noticed either in the Annals and Magazine of Natural History or in the Journal of the Astatic Society of Bengal, and a good many of them have been figured in the [lustrations of the Zoology of the Investigator.

My predecessor, Professor J. Wood-Mason, was the author of the first published notices and figures,—in the Journal of the Asiatic Socrety of Bengal, for 1887, pt. 2, pp. 206-209, pl. i, in the Annals and Magazine of Natural History for March, 1891, pp. 258-270, fig. 5, and in the Illustrations of the Zoology of the Investigator, 1892, Crustacea, pl. v, im which contributions fourteen valid new species and seven new genera are included.

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List of THE InvesTIGATOR Drrp-szA BracHyURA.

idee

Homol

Dromidz

Oxystoma.

hyncha

Oxyt

he

¢Homola andamanica,

Homola megalops, Homola profundorum, Paromolopsis boasi, Hypsophrys superciliosa,

1 ypsophrys longipes,

Arachnodromia baffini, Spherodromia kendalli, Dynomene margarita,

(Calappa exanthematosa,

Mursia bicristimana, Mursia aspera, Randallia lamellidentata, Randallia pustulosa, Parilia alcocki, Pariphiculus coronatus,

= 4 Ethusa indica,

Ethusa pygmea,

Hthusa andamanica, Ethusina gracilipes, Ethusina investigatoris, Hthusina desciscens, Cymonomops glaucomma,

Lyreidus channeri

(Physacheus ctenurus,

Physachzus tonsor, Hehinoplax pungens, Echinoplax rubida,

Cyrtomaia suhmi,

Platymaia Wyville-thomsoni, Encephaloides armstrong,

4 Encephaloides rivers-andersoni,

Sphenocarcinus cuneus, Oxypleurodon stimpsani, Scyramathia pulchra, Scyramathia rivers-andersoni, Scyramathia beauchampi, Scyramathia globulifera,

Maia gibba,

z g \ Trichopeltariwm ovale, SF ( Trachycarcinus glaucus, ( Orphnoxanthus microps,

= | Platypilumnus gracilipes, < ) Nectopanope rhodobaphes, g7 Be 5 | Sphenomerides trapezioides, = Benthochascon hemingi,

Goniosoma hoplites,

79—90 fathoms. 142-400 fathoms. 430 fathoms. 360-597 fathoms. 740-931 fathoms. 430 fathoms. 238-430 fathoms. 112 fathoms,

75 fathoms.

91-112 fathoms. 142-400 fathoms. 210 fathoms.

350 fathoms. 220-406 fathoms. 70-250 fathoms. 112 fathoms. 240-719 fathoms. 188-240 fathoms. 188-290 fathoms. 836 fathoms.

1,200-1,300 fathoms.

265-931 fathoms. 265-405 fathoms. 200-406 fathoms. 185-406 fathoms. 271 fathoms. 112-250 fathoms. 90-177 fathoms. 430 fathoms. 130-405 fathoms. 60-100 fathoms. 406 fathoms. 161-250 fathoms. 180-217 fathoms. 130-561 fathoms. 406-430 fathoms. 193-210 fathoms. 130-240 fathoms. 250 fathoms. 180-217 fathoms. 430 fathoms. 105-350 fathoms. 188-220 fathoms. 98-102 fathoms. 130-290 fathoms. 185-405 fathoms. 80-110 fathoms,

6

( Pilumnoplax sinclairi, 450 fathoms. = | Carcinoplax longipes, 220-430 fathoms. s | Psopheticus stridulans, 175-419 fathoms. = 4 Camatopsis rubida, 194 fathoms. = | Hephthopelta lugubris, 490 fathoms. v | Ptenoplax notopus, 100-250 fathoms.

| Pinnoteres abyssicola, 430 fathoms.

BRACHYURA ANOMALA. Family Homolide.

Homonta, Leach.

Homola, Leach, Trans. Linn. Soc., Vol. XI. 1815, p. 324, and Zool. Miscell. Vol. II. p. 82, pl. Ixxxviii: Latreille, [Nouv. Dict. d’Hist. Nat.], and in Cuvier’s Regne Animal, ed. 1829, p. 67: Desmarest, Consid. Gen. Crust. p. 133: Risso, Hist. Nat. Europ. Merid. Vol. V. pp. 34-85: Roux, Crust. de la Mediterranée text of pl. vii. Milne Edwards, Hist. Nat. Crust. II. 181: DeHaan, Faun. Japon. Crust. p. 105: Dana U. S. Expl. Exp. Crust. pt. I. p. 403: Heller, Crust. Sudl. Europ. p. 148: Henderson, Challenger” Anomura, p. 18: Ortmann, Zool. Jabrb. Syst. etc. VI. 1892, pp. 540 and 542: A. Milue Edwards and Bonvier, ‘‘ Hirondelle” Brachyures et Anomures (Monaco 1894) p. 60.

Carapace deep, longer than broad, quadrilateral or urn-shaped, with deep vertical sides, the gastric region well demarcated and occupying the anterior half

of the carapace, the linea anomurica distinct and dorsal.

Front narrow, forming a rostrum, which is either entire or bifid at tip and has a spine, often of large size, on either side of its base.

The orbits are quite incomplete and do not even conceal the eye-stalks, and the eyes, which project far outside them, are retractile against the sides of the carapace. ‘The eye-stalks are long and are composed of two joints, a slender basal joint, and a swollen terminal joint that carries the eye.

There are no antennulary fosse: the antennules are large and their basal joint is subglobular.

The antenna-peduncle is long slender and freely movable from its base, and is inserted in almost the same plane as the antennules: it is composed of 4 joints, the basal one of which has a strong auditory tubercle.” The flagellum is extremely long.

The epistome is fairly or very distinctly marked off from the palate. The buccal cavern is subquadrilateral, but broader in front than behind; the expira- tory canals are very well defined. The external maxillipeds are subpediform.

The chelipeds are rather slender and generally somewhat spiny. The legs are long and more or less compressed and spiny, the last pair are dorsal in position, and are subcheliform, but have the propodite dilated near the basal end and never twice the length of the dactylus.

The abdomen of the male consists of seven separate segments and is rather broad.

JI

Wood-Mason (Ann. Mag. Nat. Hist. March 1891, p. 267) separated Homola euviert from Homola barbata, basing his opinion on the form of the carapace, the position of the linea anomurica, and the form of the terminal joints of the last pair of legs.

He appears to have regarded the hollowed out portion of the carapace against which the eye can rest in retraction as a commencing orbit,—a view that seems to me to be more than doubtful.

I agree with him, however, that the differences between the two forms are of more than specific importance, and I am inclined to maintain Paromola as a subgenus. The form described by me in Ann. Mag. Nat. Hist. May 1894, p. 408, as Homola megalops now seems to me to be also worthy of subgeneric rank.

These three sections of the genus Homola may be thus characterized :—

1. Homora. Carapace square-cut, its broadest part being in front, across the middle of the gastric region: the linea anomurica rather imconspicuous, keeping close to the lateral border. Rostrum a non-cylindrical bifid tooth, with a smaller spine on either side of its base. 2nd joimt of antenna-peduncle having its antero-external angle produced to form a spine. Palate distinctly delimited from the epistome everywhere except in the middle line. The last pair of legs reach to the end of the carpus of the preceding pair.

Tyre Homola barbata (Herbst.)

Homorax. Carapace urn-shaped, its greatest breadth bemg behind, across the middle of the branchial regions: the linea anomurica conspicuous, running well inside the lateral border. Rostrum as in Homola. 2nd joint of antenna peduncle having its antero-external angle acute, but not spiniform. Palate as well demarcated from the epistome in the middle line as it is elsewhere. The last pair of legs reach beyond the end of the carpus of the preceding pair.

Tyrp Homola megalops, Alcock.

Paromota Wood-Mason. ‘“ Carapace decidedly macrurous in form,” its greatest breadth being behind: the linea anomurica very conspicuous and well inside the lateral border. Rostrum a simple cylindrical spine of large size flanked on either side by a single spine of equal or greater size. 2nd joint of antenna-peduncle not produced or specially acute at the antero-external angle. Palate everywhere well demarcated from the epistome. The last pair of legs not reaching beyond the end of the merus of the preceding pair.

Tyee Homola cuvieri, Roux.

Subgenus Homola.

Homola andamanica, n. sp.?

This may, very possibly, prove the same as Homola orientalis Henderson, though it cannot be quite reconciled with the description, still less with the figure, of that species.

In any case it is probably only a variety of Homola barbata with 3 good specimens of which—representing both sexes—it has been compared. The only differences between it and H. barbata are the following :—

The eyes are more reniform. The second spine of the lateral border is just behind the hepatic region. There are spines on the posterior border of the meropodites of all four pairs of walking legs.

Carapace elongate-subquadrilateral, its greatest breadth is across the middle of the gastric region, behind which point its sides are quite straight and vertical : it is well calcified, and, like all other parts except the antennary flagella, is covered with short soft but stiff hairs that are not thick set enough to form a coat of concealment.

Rostrum a depressed grooved tooth, bifid at tip. Four spies on the anterior border of the carapace, namely, one on either side of the rostrum, one at either supra-orbital angle.

Lateral borders of dorsum of carapace straight, very shghtly convergent, spinate; the first spine, which stands alone on the hepatic region, is of pre- eminent size, the second though much smaller than the first is much larger than any of the others.

Gastric region very well demarcated, armed with nine large spines—three in a triangle on either median area, one on either lateral area, and one on the hinder part of the central area.

Some spines on the subocular, subhepatic, and pterygostomian regions— largest on the subocular region, where they are definitely arranged in two cres- centic rows. Two spines, one beside the other, on the carapace outside the antenna-peduncle, in addition to the spmuliform suborbital angle.

Eyes somewhat reniform.

Chelipeds slender, but distinctly stouter than the legs, more hairy than the carapace, especially along the edges of the joimts. Upper and lower borders of arm spiny; wrist with rows of spines on the outer surface and a spine or two at the inner angle; lower border of hand spmy, upper border of hand denti- culate, cutting edges of fingers sharp, entire.

Legs compressed, their edges plumed with short bristles, with long bristles interspersed. The second and third pair, which are a dactyl-length longer than the first, are not quite 23 times the length of the carapace: in all three pairs both edges of the merus are armed with stout spines—at least in the distal half, and the posterior border of the propus and dactylus with compressed articulated spmes which are distant and acicular on the propus but stout very regular and close-set on the dactylus.

9

The subcheliform fourth pair of legs reach very slightly beyond the end of the carpus of the preceding pair: the merus has 3 or 4 spines on the lower border and a terminal spine on the upper border, the claw-like dactylus closes against a bunch of spines on the near end of the propus.

From the Andaman Sea, 79-90 fms.

Subgenus Homolaz.

Homola megalops, Alcock.

Homola megalops, Alcock, Ann. Mag. Nat. Hist., May 1894, p. 408: Illustrations of the Zoology of the R.1.M.S. Investigator,’ Crustacea pl. xiv. figs. 1, la.

Carapace urn-shaped, its greatest breadth is across the middle of the branchial region ; its sides, and. still more the spimulate lateral borders of its dorsum, are elegantly curved; the hairs that cover it are so inconspicuous as to be recognizable only with a lens.

Rostrum a depressed grooved tooth, entire, or emarginate at tip. Four spines on the anterior border of the carapace arranged as in H. barbata.

The only enlarged spine of the lateral border stands alone on the hepatic region.

Nine spines on the gastric region—two immediately behind the spines at the base of the rostrum, the other seven in an open S-shaped curve across the middle of the region.

A single row of spines on the subocular region, which region is remarkably hollowed for the reception of the retracted eye. ‘Two spines, one above the other, on the carapace beside the antenna-peduncle, in addition to the bluntly- dentiform suborbital angle.

Eyes reniform, very large, their major diameter being one-sixth the breadth of the carapace.

Chelipeds slender, their arms and wrists distinctly slenderer than the meropodites of the legs: in the adult male they do not reach half-way along the merus of the first pair of legs: they are covered with a short inconspicuous velvet, with hardly any long bristles on the edges of the joimts: they are armed much as in H. barbata, but the wpper border of the hand is spiny and the lower border faintly denticulate. The fingers, which have a sharp entire cutting-edge, are as long as the rest of the hand.

The legs have the surface—especially the dorsal surface—of most of the joints covered with a close short velvet, but have few or no bristles along their edges. The 2nd and 3rd pair, which are nearly a dactylus longer than the first, are nearly three times as long as the carapace: the subcheliform 4th pair reach beyond the end of the carpus of the preceding pair. The first three pair have

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the anterior edge of their greatly compressed meropodite closely spinate, and the posterior edges of that jomt and the ischium closely spinulate ; their last three joints have the edges smooth, except for a few small jomted spinules at the base of the posterior border of the dactylus. The last pair of legs have the posterior edge of their subcylindrical meropodite closely spinate and have only a single terminal spine on the upper edge, the carpus has a strong terminal spine on its posterior border, and the propus has a salient group of spines behind the middle of its posterior border forming a subcheliform stump for the serrated posterior edge of the claw-like dactylus.

Colour in life salmon-pink.

Andaman Sea, 188-220 fms., a male and a female; 370-419 fms., 3 males and 3 females. Bay of Bengal, off Coromandel Coast, 145-250 fms., a male and afemale. Gulf of Mandar, off Colombo, 142-400 fms., 2 young males.

Dimensions of carapace of a full-grown specimen 41 millim. long, 36 millim. broad.

The gills are fourteen in number on either side, exclusive of a quite rudi- mentary posterior arthrobranch to the penultimate pair of legs.

Subgenus Paromola. Homola profundorum, Alcock and Anderson, Plate I, fig. 2.

Carapace very decidedly macruriform, deep, ovoid-triangular, broadest abaft the middle of the branchial region, tapering to an acutely-spiniform rostrum of which the length is about a third that of the rest of the carapace. Diverging from either side of the base of the rostrum is a spine of similar form and size. The only other elevations on the carapace are a hepatic spine just behind the hollow for the retracted eye, an antennal spine just outside the antennal base, and a blunt denticle near the middle of the ill-defined lateral border.

The gastric region is well delimited, and the linea anomurica is broad con- spicuous and dorsal.

The stout cylindrical terminal jomt of the eye-stalks is longer than the slender basal joint, the eyes are of good size, well pigmented, and hemispherical.

The chelipeds are slender but are stouter than the legs; the arm has the outer lower border spinate and, on the upper border, a few spinules and a strong terminal spine ; both the inner and the outer angles of the wrist are armed with a strong spine, the fingers are much shorter than the hand and have the cutting- edge entire.

The legs are slender and subcylindrical, the 2nd and 3rd pair, which are slightly longer than the first, are at least three times the length of the carapace. In the first 3 pair there are a few distant spines and a strong terminal spine on the anterior border of the merus, a few articulatmg spinules at the far end of

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the posterior border of the propodite, and a comb of articulating spines along the posterior border of the dactylus—the last joint being but half the length of the last but one. The dorsal fourth pair of legs are far slenderer than the others and do not reach the end of the merus of the preceding pair: their propodite is triangular, owing to the expansion of its posterior border, and opposes a sharply-serrated edge to the less strongly toothed posterior border of the short dactylus—the parts being cheliform rather than subcheliform.

The body and appendages are coated with very short distant bristles which do not conceal the surface: there are some longer and thicker bristles along the edges of the chelipeds, and a very few scattered hairs along the edges of the legs.

Three young females from off the Travancore coast, 430 fms.

The carapace of these is about 13 millim. long, and about 9 millim. in greatest breadth.

Paromoopsis, Wood-Mason. Resembles Homola but differs in the following important particulars :—

The carapace is “more brachyurous:” it is urn-shaped and depressed, its sides being far from vertical and being overhung by the sharply defined lateral borders. The hepatic region is elongate and advanced, so that the hepatic spine is on a level with the spines of the anterior border, and helps to form a very decided “orbit.” The buccal cavern is scarcely broader in front than behind.

In other respects it agrees with Homola and more particularly with the subgenus Homolaz.

The branchial formula is the same as that of Homola.

Paromolopsis boasi, Wood-Mason.

Paromolopsis boasi, Wood-Mason, Ann. Mag. Nat. Hist. March 1891, p. 268 and fig. 5.

Every exposed surface of the body and appendages, excepting only the flagella of the antenne, is covered with an even, velvet-like, tomentum.

Carapace ending in a short triangular rostrum with an upturned tip, its greatest breadth, which is across the middle of the branchial regions, is equal to its length without the rostrum. Unlike the species of Homola, the lateral border is well-defined throughout, is carinated, is co-extensive with the length of the carapace, and ends in a large triangular hepatic spine the tip of which is ona level with the tips of the spines of the anterior border: these are four in number, one on either side of the rostrum and one at either outer orbital angle.

There is an antennal spine and spinule, there are some definitely-placed nodular swellings on the well defined gastric region, and the surface of the denuded carapace is granular, but there are no spines other than those mentioned.

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The swollen terminal joint of the eyestalk is rather longer than the slender basal joint: eyes of good size, well pigmented, hemispherical, retractile into a very decided hollow in the front wall of the hepatic region.

The 2nd jot of the antenna-peduncle is not produced or acute at the antero-external angle ; the antennary flagellum is much longer than the carapace.

Chelipeds (in the adult female and young male) short, just reaching beyond the end of the carpus of the first pair of legs: the arm is slenderer than the corresponding joint of the first three pair of legs: the fingers are longer than the hands: none of the joints are spinate.

The second and third legs, which are longer than the first by their dactylus, and longer than the fourth by their merus and dactylus, are 3 times the length of the carapace. In the first three pair of legs the anterior border of the meropodite is armed with large spines, but the other jomts are unarmed: the dactylus is slender, curved, and of great length, being hardly shorter than the preceding joint.

In the subcheliform, dorsal, fourth pair the anterior border of the merus ends in a spine and the posterior border of the merus is spiny throughout, the propus is much dilated and toothed at its basal angle posteriorly, so as to be l-shaped and has one or two spines on the undilated portion of its posterior border, and the dactylus is short and is toothed along the posterior border.

The abdomen of the male consists of seven segments. The carapace of an adult female is 45 millim. long and 43°5 millim. broad. The colours in life vary from red to bluish-pink.

In the Indian Museum are a large female and three young females from off the Andamans, 480-500 fms., 498 fms. and 561 fms.; a young male a large adult female and four young females from off the Travancore coast, 406 and 430 fms.; a large female with eggs from off the Laccadives, 360 fms. ; and a young female from off Colombo, 597 fms.

Hypsopurys, Wood-Mason.

Carapace deep, longer than broad, quadrilateral or ovate-oblong, with deep vertical parallel sides, the gastric region well delimited and occupying its ante- rior half, the linea anomurica dorsal, distinct or indistinct.

Front narrow, forming a simple or bifid rostrum which has a spine on either side of its base.

The orbits do not afford any concealment to the eyes, but form, on either side of the rostrum, a broad concave facet sharply marked off from the rest of the carapace by a ridge that arches round dorsally from the rostrum to the antennal spine: at the upper and inner angle of this facet is a well defined

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hollow that catches the knee of the 2nd and 8rd joints of the antennulary peduncle when flexed. The eyes are well formed: the terminal joint of the eyestalk is barrel-shaped much as in Homola, but the slender basal joint is short or obsolescent, so that the eyes do not appreciably project beyond the edge of the orbital facet.

The antennules and antennz are identical with those of Homola.

The mouth-parts also are very like those of Homola, but as the outer border of the merus of the external maxillipeds is hardly at all expanded these append- ages are even more pediform than in Homola.

Chelipeds slender, spiny, equal. Legs of the first three pair long, with broad compressed meropodites. Fourth pair of legs, dorsal in position, short, very slender, cheliform, their dactylus, which is many times shorter than their propodus, shutting down against and co-terminous with the slightly expanded distal end of the propodus.

The abdomen of the male consists of seven separate segments.

In general form Hypsophrys resembles Homola barbata, but it differs from Homola in the following particulars :—

1. The eyestalks are like those of Dromia, the long slender basal joint of Homola being reduced to next to nothing.

2. Though there are no true orbits there are distinct orbital facets, and the homologies of these with the orbits of Dromia—in respect both of conform- ation and of common use for eyes and antennules—are unmistakeable.

3. The external maxillipeds are unequivocally pediform, the merus being hardly broader than the ischium.

4, The fourth (last) pair of legs have the subchele or chele quite different im form: the propodite is long and is slightly expanded at its distal end, and the dactylus is a minute jot, ever so much smaller than the propodite, that shuts down against the distal border of the latter like the blade of a knife.

Wood-Mason, who regarded the plane or hollow surface on the antero- lateral wall of the carapace of Homola, against which the eye can be retracted, as a commencing orbit, said that Hypsophrys has no orbits; and this is quite correct if the surface referred to be really an orbit.

But if we compare the carapace of Hypsophrys with that of Dromia, and regard the orbit as the hollow included between the rostrum and the antennal spine, then Hysophrys has far better orbits than Homola, for the space in question is a distinct depression sharply marked off from the rest of the carapace by a ridge.

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14.

Hypsophrys superciliosa, Wood-Mason.

Hypsophrys swperciliosa, Wood-Mason, Ann. Mag. Nat. Hist. March 1891, p. 269: Illustrations of the Zoology of the Investigator,” Crust. pl. xiv. figs. 4, 4a, 1895.

Rostrum simply pointed. Linea anomurica rather indistinct.

Four small spines or teeth on the anterior (orbital) border of the carapace, two being far apart at the base of the rostrum and one at either outer orbital angle. Two, or all four, of these teeth may be obsolescent or obsolete.

Lateral borders of dorsum of carapace not defined, except by a single isolated spine on the hepatic region. Gastric region sharply subdivided into three subregions, of which the lateral are somewhat nodular. Two or three spines on the subhepatic and suborbital region, the innermost of which is “antennal,” also sometimes a few spinules.

Eyes well formed and facetted, but pale. Antennal flagella about half again as long as the carapace.

The pediform external maxillpeds have their surfaces and edges devoid of spines.

Chelipeds slender, but much more massive than the legs, about half a hand- length shorter than the first pair of legs in the adult male: spines and spinules in rows on edges and on both inner and outer surfaces of arms, wrists and hands : fingers about three-fourths the length of the palm.

The second pair of legs, which are slightly longer than the first and third and considerably more than twice the length of the fourth, are slightly more than three times the length of the carapace.

In the first three pair the meropodites are compressed with the anterior border spiny and the posterior border much less strongly and profusely spiny, the other jomts are slender and unarmed except for a few articulating spinelets at the far end of the posterior border of the propodite and in the basal half of the posterior border of the dactylus, the dactylus is slightly shorter than the propodite.

The fourth (dorsal) pair are very slender and are unarmed except at their cheliform ending: their propodite is many times longer than the dactylus.

The terminal joint of the male abdomen is bluntly triangular.

There are some soft bristles on the chelipeds, and a few on the legs, and some very short and inconspicuous hairs on the carapace.

Colours in life, pink.

The carapace of a large egg-laden female is 19 millim. long and 15 milhm. broad.

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This species has frequently been taken in the Laccadive Sea and in the sea to the north of the Laccadives at depths ranging from 740 to 931 fms., on soft bottoms.

In the Indian Museum are more than 30 specimens representing both sexes adult and in young stages.

Hypsophrys longipes, Alcock and Anderson. Plate I, fig. 1.

Rostrum deeply bifid. Linea anomurica distinct.

Four large spines on the anterior border of the carapace—two close together at the base of the rostrum, one at either orbital angle.