Sapa h0 =Frcbatheh GemA cheh 2 nit wp Saree SN A er porwr Cece tenet See NH TT eee rete ecnsrer eure ee ret ee ee ere ere ates oho pa r rere yee ta iand ae : ry HARVARD UNIVERSITY Perea Lass LIBRARY OF THE MUSEUM OF COMPARATIVE ZOOLOGY Depos ted by Alexander Adgass 12, 37650 GG. tb phtiws "ye BRITISH SESSILE-EYED CRUSTACEA. ‘ LONDON: ; PRINTED BY WOODFALL AND KINDER, ANGEL COURT, SKINNER STREET. Alerts TOR ¥ OF THE BRITISH SESSILE-EYED CRUSTACEA. BY C. SPENCE. BATE, H.K.S., EES. ETC, J. 0. WHS ITWOOD; M-A., F.L.S., HOPE PROFESSOR OF ZOOLOGY IN THE UNIVERSITY OF OXFORD, ETC, IN TWO VOLUMES.—VOL. I. LONDON : JOHN VAN VOORST, PATERNOSTER ROW. " M.DCCC.LXIII. / a) ‘i Te : - i eck tae an ee eee NEL de rr ay nie Hwee ore ay ' = Se a hE A = a NEG “" S. *. ‘Ii ii w oe aa = ene: wey 7 “ih + 47 i Tijua i Y ‘ . ie Ae 9 ay vd + 1 Piss) i , Was i Papen ye ar in ; a evn RPA ee. aes my : ‘a hs ay gt li mete a a“ ~ oe Ondet Aste aibba » Se Disc ‘igs geranain: Vat: elie ih he present “ yk iis »* Oh Sih eA Nap oe Se es an ze ‘Wrestle eminem Ce ae MR eas nec! at Lyin hg 2a Gece, ta ae i. a Bi Sel i hehe Sedans * ees . m ekwiiino': walebis the Qemne thre df the: great ot wien the viene path, wopatrpically périaps © attr obtiir CO ams na. Py ue higher. orden, the | igh he) Grae Pekin eH), “encendubde tpt theokte te circa ~ (* nis vores 2 a ies i yep ee Pry ity se i es te Mt ‘Soi ie tis ‘eke, “ll BS ce ae = 0 chap Saige, | sys ALE os ne oe thes pie 2 wal Phe, “yt oe fot Uitig amet... they peti in, tise une 2 as dg oe fe, Rina. 28 is ttt he Ga te Sehic, Be. . a Sait ts Nite ti: Sank Ae Buu ios 3 dart gyal, Sy lane jah hed ndnalton Progen. - ee ate hich CR site gl . "le er ~ htt ‘Per, eg Thema: «Sam ae et Nose ie. gg ae? eh ar ag oa BRITISH SESSILE-EYED CRUSTACEA. Order AMPHIPODA.* TuIs name was given by Latreille to the present order + of Crustacea on account of the animals contained in it having both swimming and walking legs, and to distinguish it from the order Isopoda, in which the legs are adapted for walking only. The Amphipods exhibit the characters of the great class of which they are a part, more typically perhaps than any other Crustacea. In the higher orders, the head, from its great development, encroaches upon the body, and in the lower orders, the body encroaches upon the head. The type { of a class, order, or indeed any other group, is to be found in its centre, and not at either extremity of the series. The Amphipoda are formed upon the Macroural type, from the normal condition of which they differ in the three following important particulars: first, there is no * Derived from the Greek euzgw, both ; wodes, feet. + It must be borne in mind that, for the considerations set forth in the Introduction, the order Lemodipoda, proposed by Latreille for Caprella and its allies, has been rejected—that group being regarded as an aberrant division of the Amphipoda. + The following definition of a type is given by Professor Whewell, as the 92nd aphorism concerning ideas, in his ‘‘ Philosophy of the Inductive Sciences :’”’—‘‘ Natural groups are best described, not by any definition which marks their boundaries, but by a type which marks their centre. The type of any natural group is an example which possesses, in a marked degree, all the leading characters of the class.”’ B 2 AMPHIPODA. carapace covering the upper portion of the segments of the body, consequently these segments are themselves made dorsally perfect; second, the gnathopoda, which, in the Macroura, constitute the two outer pairs of mouth- organs, become prehensile instruments, increasing the number of legs to seven pairs; and, third, the tail, or caudal apparatus, consists of four segments instead of two. In the Amphipoda, on the other hand, the various seg- ments are nearly equally developed throughout, whilst, from being generally compressed at the sides, or cylin- drical in form, the animals of this order are easily dis- tinguished from the Isopods, which are, for the most part, broad and flattened in shape.* i) Ss ¥ v f=-) —— Ze * Hence, to a certain degree, the Amphipoda constitute a group parallel in their own division with the Macrowra amongst the Decapoda, whilst the Tsopoda form an analogous group to the broad and flattened Brachywra, the Caprelle offering a kind of parallelism with Squz//a and its allies. GENERAL CHARACTERS. 3 TABLE of the External Organs of the Amphipoda, with the Letters respec- tively attached to each, as employed throughout the engravings in this work. C Cephalon H to O Pereion P to Z Pleon (C) a b Eyes : : 3 : : Superior antenne: 1, first; 2, second; 3, third joint of pe- duncle; 3”, secondary ap- pendage; 4, flagellum. Inferior antenne: 1, first; 2, second; 3, third; 4, fourth; 5, fifth joint of peduncle ; 6, flagellum. Mandible; @’ mandibular ap- Head. Body. Tail. Eye. Superior antennz: 1, first; 2, second; 3, third joint of pe- duncle; 5”, secondary appen- dage; 4, flagellum. Inferior antenne: 1, first; 2, second; 3, third; 4, fourth; 5, fifth joimt of peduncle; 6, flagellum. d Mandible or jaw; d” man- pendage. dibular appendage or palpus. e First maxilla, or first siago- e First maxilla. nopodos* . 5 : Jf Second maxilla, or second f Second maxilla. siagonopodos : C g Maxillipede, or third siago- ; | g Foot-jaw or pedipalp. nopodos hlst) ing the 2nd maxillipede, or fourth siagonopodos. t 2nd g the ded mast, = yen 1st Gnathopodos, mips | ing the 3rd maxillipede, or fifth siagonopodos . | tlegs. k Ist Pereiopodos . C ~*}/s Kaard t 2nd do. ; < . | JU 4th m 3rd do. ; : - | mdth n 4th do. : : ; n 6th o Oth do. : : Si lommtbey} (P to Z) p Ast Pleopodos. : : p Ast q 2nd do. ‘ : 3 ; q 2nd }natatory legs. * ard. do: 2 : C : r 3rd s 4th do. or 1st Uropodos s Ist ¢ 5th, do: 2nd_ do. t 2nd feandal appendages. » 6th do. 3rd_ do. » 3rd z Telson z Terminal joint or middle tail-piece. The corresponding joints of all the limbs are marked with the same number, and bear the same names throughout. We take one of the Gnathopoda as the type. 1 Coxa : : Coxa. Iv Branchia 1” Plate of incubatory pouch 2 Basos . : ‘ Thigh. 3 Ischium : ; Knee, 4 Meros; 4”, inferior angle Metacarpus; 4”, inferior angle. 5 Carpus; 5”, inferior angle . , . Wrist; 5”, inferior angle. 6 Propodos; 6/,palma; 6”, inferior angle; Hand; 6’, palm ; 6”, inferior angle ; 6”, inferior margin ; 6’””, supe- rior margin. Finger ; 7”, Nail. 6”, inferior margin; 6”, superior margin. 7 Dactylos; 7”, Unguis . * This name is here suggested as the Greck equivalent for the Latin name of the five pairs of appendages succeeding the mandibles, which were collectively termed pates-mdchoires by Cuvier, Savigny, &e. The lévres supérieure and inférieure of these authors are omitted for the reasons assigned in the following page.—(I. O. W.) 9 BS 4 AMPHIPODA. The animal is naturally divided into three parts: the head (or cephalon, c), formed of a single segment; * the body (or pereion), consisting of seven segments (H to 0) ; and the tail (or pleon), formed of six segments (P to v), exclusive of the terminal scale (or telson, z). These divisions are distinctly visible, and never encroach upon each other; while the appendages assume characteristic forms in each division. Those which belong to the head are more or less connected with the organs of sense. The eyes (a) are sessile and compound. Their normal position is between the bases of the superior and inferior antenne. In the Orchestiide and near allies they are on the top of the head, to which position they are thrust by the great increase of the size of the two basal articula- tions of the antenne and their absorption into the ante- rior portion of the head. The outer integument of the eyes is never divided into facets, except in some genera of the Hyperina. In many of the Phoxides the eyes appear to be wanting; but this is probably caused by the absence of any colouring pigment, or its dispersion after death, rather than from the absence of the organ of vision. In SPIO “aire: == eprom > Seeprmed Ary sc ae * epLmypyp xprirydoroy x puUeururesy — VLLOYLIL NT * * xprIygseqor9, = VILOPVI[VY “ATLUUG OCIA, LNGNGONVEUVY UVTINAVL “MOISTAID -qug = “CULLeVULUL ey “UOISTATC, Ba ae "@I[VULLIO NT ~~ ‘dno ‘VaOdIHdNV J “IOplo AMPHIPODA. Wk Group—NORMALIA. This group comprises the typical Amphipoda, and in- cludes the whole of the order except those forms which have some of the appendages absent, or have the first joint of the legs absorbed into the body of the animal. It is synonymous with the order of Amphipoda of Latreille, Milne-Edwards, &c., and is separated into two divisions—namely, GAMMARINA and HyPErRINa. Division—GAMMARINA. Distinguished from the other division of the group by the smallness of the eyes, the normal form of the antenna, the size of the foot-jaws, and the largeness of the squa- miform plates of the legs. This division corresponds with Milne-Edwards’s family of Crevettines, and also with that of Gammaridea of Dana. It is subdivided into VageanTiaA and Domico.a. Subdivision—VAGANTIA. The Vacantia have always the inferior antenne ter- minating in a flexible multiarticulate flagellum, and the posterior pair of caudal appendages are fringed with fine hairs or short spines, and are never furnished with hooks. They construct no abodes to dwell in, but wander from place to place, swimming or walking in the sea, and hopping or wriggling along upon their sides on land. This subdivision represents Milne-Edwards’s tribe of Sauteurs. It consists of the two tribes SALTATORIA and NaTaToria, each consisting of a single family. Tribe—SALTATORIA. In this tribe the posterior caudal appendages are never longer than the two preceding pairs. , The hairs upon the 12 ORCHESTIIDA, animal are short and stiff. The mode of progression, when out of the water, is by leaps. The animals are generally terrestrial or subaquatic. ‘This tribe contains but a single family. Fam.—ORCHESTIDE. The superior antennz are never longer than the inferior, and never furnished with a secondary appendage. ‘The mandibles are without a palpiform appendage. The squamiform joints of the legs are largely developed. The caudal appendages are very short and stout, and the pos- terior pair only possess a single branch. The following vignette represents the Hoe Gate, Ply- mouth; the house in which Dr. Leach was born. TALITRUS, 13 AMPHIPODA., ORCHESTIID 2. SALTATORIA, Genus—TALITRUS, LatreILue. Generic character. Superior antenne short and rudimentary, Inferior antenne with the basal joints fused into the facial wall of the cephalon. Mandibular palpi obsolete. Maxillipedes not unguiculate. First pair of gnathopoda simple; second pair small and feeble. Coxze of third pair of pereiopoda as deep as the coxee of the second, and divided into two equal lobes. Telson rudimentary.* THE eyes are near the top of the head. The superior antenne are very short, not reaching to the extremity of the second free joint of the inferior. Inferior antennz with the two basal joints absorbed into the frontal wall of the head. Fingers of the foot-jaws not unguiculate. First pair of legs not having a subchelate hand in either sex: second pair of legs smaller than the first pair, and imperfectly subchelate in both sexes. Coxe of the fifth pair of legs subequally bilobed, and nearly as deep as the cox of the preceding pair. Middle scale of the tail rudimentary or single. The genus Tualitrus was first proposed by Latreille in his ** Précis”’ (1796), under the name of Gammarus, for the reception of the Amphipoda with short upper an- tenn ; the remainder, with longer upper antenne, being arranged in his genus Carcinus. The name Talitrus itself * The structural terms employed in the short generic and specific characters of the Amphipoda are those proposed by Mr. Spence Bate in his ‘‘ Report on the British Edriophthalma,’”’ published in the Reports of the British Asso- ciation for 1855. In the text the ordinary English names of the various parts are adopted, as given in the Table of External Organs in page 3. 14 ORCHESTIIDA. first appears in the year 1802, both in the third volume of Latreille’s “‘ Histoire générale des Crustacés et Insectes,” and in the second volume of Bosc’s ‘‘ Hist. nat. des Crustacés,” the latter writer giving Latreille the credit of the invention. This must be borne in mind, because Latreille, in his “ Genera Crust. et Ins.,” vol. i., 1806, refers the genus Talitrus to Bosc as its author. In the last-mentioned work we find the genus, according to the views of its founder, to be as extensive as our family Or- chestiidz (which it would consequently have been more correct to have named, after the present genus, Talitridz), embracing the whele of the saltatorial species. Subse- quently Leach separated the species with the first pair of legs cheliferous under the name of Orchestia. In this he has been followed by all subsequent writers. Milne- Edwards, Dana, Desmarest, and others, however, intro- duced into this genus those species which have the second pair of hands as large as in the males of Orchestia; but Nicolet * has very justly separated them from Talitrus, under the generic name of Orchestoidea. Brandt + has likewise done the same, but, without being aware of what Nicolet had proposed, has given to the same genus the name of Meygalorchestia, which Stimpson has followed. Accepting this latter separation of the species into two genera, Talitrus appears to be peculiar to the European coasts and the southern shores of the Mediterranean. The species 7. brevicornis of Edwards and IT. Novi-Zealandie of Dana, both from New Zealand, have only been described from females, and since the female specimens belonging to the genus Orchestoidea resemble Talitri, it is not improbable that these may likewise be the females of Orchestoidea. * In Gay’s ‘‘ Hist. phys. de Chile,” iii. p. 229. Crust. pl. 2. fig. 4. + Bull. Acad. St. Petersbourg, 1851, ix., pp. 133, 310. TALITRUS. 15 There can be little doubt that, under the name Cancer locusta, the great Swede grouped more than one species. Hence the difficulty of determining the specific name entitled to priority of publication—(if this difficulty exists with Linnzus, how much greater it must be with earlier writers!)—a circumstance which accounts for the discrepancies of opinion among later authors, some attributing the name to a species of Gam- marus, and others to one of Talitrus. For our part we think that Linneeus included species of both genera, but certainly Taltrus was one; he says that it is entirely of a blue colour, that the hands of the two fore pairs of legs are adactyle, and hence that there are seven pairs of slender feet, and that he had seen it *‘ad montem Thors- burg, in mari juxta Gotlandiam.” On the other hand, he refers to Roesel’s figure of the fresh-water Gammarus, and adds that the tail is trifoliated, *‘ intermedio subulato.”’ His disciple Fabricius has added to the confusion by giving the Linnean character of the legs, but adding that the tail was furnished with bifid spines, with the locality ‘‘in Europz maritimis frequentissimus dorso innatans, ’ etiam szpe in fontibus et fossis stagnantibus:’ thus comprising at least three species with different habits. Under these circumstances, and in order to avoid the confusion arising from the same specific name having been also applied to the common shore species of Gam- marus, it might have been correct to have retained for the species of Talitrus the name of Saltatrix, given to it by Klein, and adopted by Montagu and Milne-Edwards ; but since Turton, in his translation of the “ Systema Nature,” as early as 1806, used the specific name which most English authors have employed, we consider that we are justified in continuing it, 16 ORCHESTIID ®. AMPHIPODA., ORCHESTIID A. SALTATORLA. TALITRUS LOCUSTA, Linnzeus ? (The Sand-Hopper.) Specific character. Superior antenne only reaching to half the length of the penultimate joint of the peduncle of the lower. Last joint of the peduncle of the inferior antennze nearly twice as long as the penultimate. First pair of gnathopoda robust and powerful. Second pair of gnathopoda feeble, membranaceous, terminating in an imperfectly-formed sub-chelate hand ; dactylos small and remote from the extremity of the propodos. Pos- terior pair of pleopoda very short. Telson rudimentary. Length, half to three quarters of an inch. Cancer Locusta, Linnzus, Fauna Suec. No. 20422* Syst. Nat. ii. 1055, and Edit. Turron, vol. ui. p. 760 (1806). * The descriptions of the species of Amphipoda given by the earlier carci- nologists are by no means sufficiently precise to allow satisfactory identifica- TALITRUS LOCUSTA. 17 Squilla saltatrix, Kern, Crust. p. 68, f. D.E.F. Cancer (Gammarus) saltator, Montagu, Linn. Trans. ix. p. 94. t. 4, f. 3 (male). Talitrus Locusta, LATREILLE, Hist. Nat. Crust. et Ins. vi. 229. Leacu, Linn. Trans. xi. 356, PENNANT, Brit. Zool. iv. p. 21. Pattas, Spic. Zool. fasc. 9, t. 4, f. 7. Luacu, Edin. Encyel. Crustaceology, vol. vii. p. 432. Dusma- REST, Cons. p. 260, t. 45, f. 2. Russo, Hist. Nat. de ’Kurope Meridion. vol. v. p. 98. Gurrin, Exped. Scien. de Moree, iii. p. 5) sect. 2; p. 44:\< Zool) pl: 27, f. 4, e: Brepisson, Cat. des Crust. du Calvados, 1825, p. 250. BovucHarp CHANTEREAUX, Crust. Boulonnais, p. 128. Wuurrr, Cat. Crust. Brit. Mus. 1847, Popular Hist. Brit. Crustacea, p. 160; Cat. Brit. Crust. Brit. Mus. p. 48. GossE, Mar. Zool. vol. i. p. 142. Spence Batt, Ann. Nat. Hist. 2nd ser. vol. xix. p. 185; 1857, Cat. Amph. Brit. Miusspy OF plac, tes Talitrus Saltator, Minnr-Epwarps, Ann. Sc. Nat. xx. 364, Hist. des Crust. iii. p. 18. Cuvimr, Régne An. (Ed. Crocuarp), t. 59, f. 2. Lucas, Exped. dans lV Algérie. Zappacu, Syn. Crust. Pruss. p. 4. TrEmpieton, Loudon Mag. Nat. Hist. vol. ix. p. 12. (Female) Talitrus littoralis, | Leacu, Edin. Encyclop. vol. vii. p. 402, Art. Crustaceology. Tue general appearance of the animal is strong and powerful, and but slightly compressed laterally. The tail is very short, and generally lies folded beneath the body ; from which position, when forcibly struck out, it enables the animal to spring to a considerable distance. Hence it derives its English name of “ hopper,” and its French cognomen of “ Puce de mer.” Its generic name, Talitrus, signifies a ‘ fillip.” The male is larger and more robustly formed than the female. tion, and unfortunately, in respect to the Linnean species, the Linnean cabinet affords us no help, as it does not contain any of his typical spe- cimens, C 18 ORCHESTIIDA. The eyes are large, irregularly round, and placed near the top of the head. The upper antennez are so small that they seem almost rudimentary. The lower antennz in the male are long, sometimes two-thirds the length of the animal; in the females and young males they are much shorter. The peduncle is longer than the fla- gellum, and appears to consist of but three articulations, the two basal ones being fused into the frontal wall of the head, a circumstance which forces the superior antennz and organs of vision nearly to the top of the head, a position not common in the Amphipoda. The olfactory denticle is wanting. The ergan of smell probably undergoes some change to meet the altered condition of the existence of the animal from that of marine crustacea generally. The mandibles are powerful organs, armed at the biting edge with teeth, formed more for tearing than for cutting ; below which a second row of denticles is fixed upon a plate, which is movable. A few strong hairs or spines, curved inwardly, are situated between the incisive margin and the molar or grinding tubercle. This last is a prominence at the inner base of each mandible, and is crowned by very minute denticles, and corresponds with a similar grinder in the opposite jaw. By the joint action of these two molar tubercles an imperfect mastication is effected . The foot-jaws are not unguiculate—that is, the last ar- ticulation does not terminate in a sharp, nail-like extre- mity, but ends obtusely, the tip being fringed with short hairs. A squamiform plate is developed from three of the articulations, of which the first, the most internal, is the largest, and is furnished at the extremity with three small stout spines or teeth. The apparatus which com- poses the mouth projects anteriorly beyond the head, by which means the animal can the more easily gather its TALITRUS LOCUSTA. 19 food from fixed positions—a circumstance, according to Leach, from which it has earned the specific name of Locusta. The first pair of legs are simple, the terminal joint being slightly curved, but not having the power to impinge against the preceding. They are strong and efficient for the purpose of burrowing or hooking to any substance, but have no prehensile capability. The second pair of legs are feeble, of a membranous appearance, and generally lie folded up close beneath the body. The terminal joint is short, almost obsolete, and placed at a considerable distance from the extremity of the preceding, appearing to be an inefficient organ.* The two next succeeding pairs of legs are strong and efficient members for perambulation, but they are not so powerful as the last three pairs. The first or scale-like joint affixed to the sides of the body, is largely developed in each leg. That of the fifth pair of legs is bilobed, and is anteriorly nearly as deep as the one that precedes it. The swimming fins are short, being never required, since the animal never voluntarily seeks the sea. The lateral appendages of the tail are short and stout. These, with all the other limbs except the second pair of hands, are furnished with fasciculi of short, spine-like hairs. These hairs are generally blunt at the tip, and furnished laterally with a slight secondary appendage, about one- * In Milne-Edwards’ figure of the male of 7. saltator, stated to have been copied from the living specimen (R. An. Ed. Crochard, Crust., pl. 59, fig. 2a), the second pair of legs is represented as evidently larger than the first pair, but destitute of spines. This figure, therefore, appears to us rather to repre- sent Talitrus Beaucoudrait of M.-Edwards. It must be borne in mind that, throughout the Amphipodous portion of this work, the limbs on one side of the body are alone represented, in order to prevent confusion ; the opposite limbs being identical in structure. ce 2 20 ORCHESTIIDZ, third from the apex. The structure of the hair towards the point is obscurely spiral. Those upon the tail are often considerably worn down by the friction induced by leaping. The central tail-piece is represented in this species by two small calcareous nodules.* The [2% Se surface of the body is highly ponenelt An examina- tion of the structure of the integument by the aid of the microscope shows traces of the original cell-character of the tissue and the granular arrangement of the salts within the cells. There are, moreover, certain larger markings that assume somewhat the form of the letter T. But we are not able to recognize them as associated with any peculiar function. The female exhibits the character of the species less strikingly than the male, being considerably smaller, and having the antenne shorter. So great indeed is the difference, that Leach, in the ‘f Edinburgh Ency- clopzedia,” inserted it ay a distinct species, under the name of Talitrus littoralis, an opinion which he afterwards corrected in the *‘ Linnean Transactions,” vol. xi. The Sand-hoppers dwell near the margin of the sea, where the highest spring-tides rise. They are never found in the water, but dwell beneath the decaying sea- weed, or other stray substances which preclude the eva- poration of moisture from the scorched sandy beach. Mr. Gosse tells us that he has found them at the depth of several inches in half-rotten beds of algze, where the fer- * Our figures in page 16 were taken from very large males, captured at Weymouth, by Professor Bell. In these individuals the central tail-piece is heart-shaped and spined (fig. z), and the upper antenne extend to the tip of the penultimate joint of the peduncle of the lower, of which latter the rela- tive proportions of the joints were carefully measured for delineation.—(W.) TALITRUS LOCUSTA. ra | mentation has induced a heat so great that he could scarcely bear his hand. When the summer is hot, and no moisture exists be- neath the decomposing seaweed, they burrow into the sand two or three inches deep, until they find moisture enough to suit their comfort; whence they come out to feed upon any carrion left by the retiring tide. Offal, which would otherwise decompose and infect the air, is thus by their assistance oftenrapidly removed. They are not very dainty feeders. We have seen them enjoying their repast upon a common earth-worm; drowned pup- pies and other mammals, afford a luxury to thousands ; and, when they can get nothing else, they are content to feed upon each other, Mr. Adam White, in his excellent little manual, tells us that millions of these creatures were seen by Paley springing in the air so lightly that, at a little distance off, they marked the circuit of the shore as a line of mist. The religious mind of the observer saw in this shadowy wall the action of expressed gratitude for existence. Upon the sands of Whitsand Bay, our friend Mr, Swain informs us that one day, at a picnic party, he saw ‘‘ not millions, but cartloads,’’ of this species lying piled to- gether along the margin of the sea. They hopped and leaped about, devouring each other as if for very wan- tonness. A handkerchief, which a lady let fall amongst them, was soon reduced to a piece of open work by the minute jaws of these small creatures. The numerical abundance of this species is kept within bounds by enemies more powerful than they can be to one another. The ring plover and other shore birds rapidly pick them up, and little beetles prey upon them, among which the Cillenum laterale and Broscus cephalotes have been observed. 22 ORCHESTIID A. It is in the summer months that they occur in such vast numbers. In the winter there is scarcely one to be seen ; and when the frost is sharp, and the snow les upon the ground, the Sand-hoppers appear to have retired into winter-quarters. This was first observed by Colonel Montagu. At this season we have noticed their general absence at Whitsand Bay, as has also our friend Mr. Barlee, at Exmouth. But Mr. Gosse informs us that they have been found at Weymouth, under the ‘ half- rotten beds of algze (chiefly laminaria) ” all the winter. When captured they feign death, and often keep up the deception for a.considerable time. In this position, by the close packing of their scaly appendages, they are more secure from the attacks of beetles and other smaller enemies. Their colour when alive is a light fawn, marked down the centre of the back with black. This species is one of the most perfect dwellers upon the land that we have among the European Amphipoda. They die if kept in water for any time, yet a certain amount of saline moisture appears necessary to lubricate the branchiz. Though residing on land, they possess a purely aquatic character. In the southern hemisphere allied species have been taken many miles inland upon the stems of succulent plants. This species is probably to be met with upon all the sandy shores of the temperate zone in southern and western Europe. In this country we have received it from the Moray Frith, in Scotland, where, the Rev. George Gordon says, it occurs in great abundance. Mr. W. Thompson and Professor Kinahan record it as common in Ireland. Specimens from Cultra, Belfast Bay, collected in May by Mrs. Patterson, and others from Newcastle, county Down, collected in the autumn, are preserved in the late W. Thompson’s collection in TALITRUS LOCUSTA. 23 the Belfast Museum. We have noticed it on the south- ern shores of England and Wales. Milne-Edwards states that it is very common upon the north and west coasts of France. M. Guérin Méneville has received it from the shores of Greece ; Risso took it at Nice, and Lucas in Algeria. So that it will be important to record upon what sandy shores it is not to be found. It does not occur in Greenland, being omitted by Kroyer, nor does it appear in the work of Bruzelius on the Scandinavian species published at Lund in 1859. The accompanying vignette of Whitsand Bay, near Plymouth, is from the talented pencil of our friend Mr. Philip Mitchell, of the New Water Colour Society. Q4 ORCHESTIIDA, AMPHIPODA. ORCHESTIID&. SALTATORIA. Genus—ORCHESTIA, Lracu. TaiTrus (part), LATREILLE, Generic character.—General appearance of Talitrus, but having both pairs of gnathopoda subchelate. The second pair in the male large and powerful; in the female small and feeble. Telson single and well developed. THE superior antenne are as short as in Talitrus, and are often recurved. ‘The inferior antenna, as in that genus, have the two basal articulations incorporated into the anterior or frontal wall of the head, and destitute of the olfactory denticle. The mandibles are without an appendage,* and the whole of the organs of the mouth are largely developed. The two anterior pair of legs are furnished with prehensile hands, the first pair small, the second large and powerful in the male, but small and feeble in the female. The squamiform basal joint of the fifth pair of legs is subequally bilobed, the anterior lobe being as deep as the scale of the preceding legs. The posterior pair of caudal stylets consist only of a single branch. The tail-piece is single and well developed, entire, triangular, with the margin spinous. This genus was founded by Leach to receive the Cancer (Gammarus) hitoreus of Montagu. That Dr. Leach was * A rudimentary palpiform appendage in an Egyptian species of Orchestia is represented by Savigny near the base of the jaw (copied in our figure, p. 27, fig. d), but we have never seen it in any species. ORCHESTIA, 25 well aware of the variation of the form of the legs in the opposite sexes of the type of the genus is fully evidenced by an original drawing now in the Hopeian collection at Oxford, containing highly-magnified figures of the fully-developed male, of a variety of the male with smaller second legs and undilated hind legs, and of the female with simple legs, the sexes being indicated, and the species named “ Orchestia littorea,” in Dr. Leach’s peculiar handwriting. Liljeborg had also, in his account of the Crustacea collected by Dueben in Norway in 1844, noticed the sexual distinctions of Orchestia littorea, de- scribing the female as exhibiting the typical form of Talitrus, and the male that of Orchestia, the female, in fact, closely resembling the Taltrus tripudians of Kroyer except in the length of the fourth and fifth pairs of legs, as compared with those of the second pair. The genus was previously confounded with Talitrus, and the female continued so until Fr. Miiller pointed out the relative distinction of the sééond pair of hands, and their near resemblance to those of Talitrus.* Dana has more recently divided the genus, distinguishing those in which the female has the first pair of legs not developed into a subchelate or prehensile hand (in fact, a true Talitrus) ; while the male is a true Orchestia; that is, having the first pair of legs subchelate. This division, under the name of Talorchestia, together with those of Talitrus and Orchestia, he considers to be but subgenera of the genus Orchestia. The genus Orchestia is perhaps the most cosmopolitan amongst the Crustacea, and may likewise be classed amongst the most terrestrial species of Amphipods. It has been taken from the north of Europe to Cape Horn, and * Archiv. fir Naturgeschichte, 1848, p. 53. 26 ORCHESTIIDA. from New Zealand to the northern coasts of America. Yet with this vast geographical range we are not aware that a single species has been recorded within the tropics or arctic regions: although northern Egypt and the coast of Algiers are mentioned by Savigny and Lucas. Dana and Stimpson in America have not taken them in tro- pical latitudes. : Their common habitat is upon the sea-shore, out of the reach of the waves, but Dana has found them, and exotic species exist in the British Museum, which have been taken in shady woods some miles from the sea-coast, and Mr, Stimpson, the naturalist of the American Japanese expedition, informs us that he also has captured them in inland places. The Orchestiz must be reckoned among our smaller shore-cleaners, feeding upon the offal left by the receding tide. Say has noticed of an American species, that when alarmed, the individuals will seize a portion of their food, and skip with it towards their holes in the sand, where they can devour it at leisure. The accompanying vignette of figures, in the costume of the South of Wales, is by the promising pencil of our friend Mr. Sydney Whiteford. ORCHESTIA LITTOREA. 27 AMPHIPODA. ORCHESTITD A. SALTATORIA. ORCHESTIA LITTOREA. (Shore-Hopper.) Specific character.—Propodos of the second pair of gnathopoda having the palm convex, slightly oblique, with a small tooth at the inferior angle. Posterior pair of pereiopoda, having the carpus and meros in the older males largely developed. Length !3 of an inch. Cancer (Gammarus) littoreus, Montaacu, Linn. Trans. ix. p. 96, t. 4, f. 4. Orchestia littorea, Leacu, Edinb. Encycl. vii. p. 402, pl. 21, f, 6; Linn. Trans. xi) p. 3565 Encyel. Brit. Suppl. i. 424. Drsmarerst, Cons. p. 261, t. 45, f. 3. Samovrziz, Ent. Comp. p. 102. Larrertin, Encyel. Méth. pl. 336, f. 1. Wurrr, Cat. Brit. Crust. p. 48; Pop. Hist. Brit. Crust. p. 162, pl. x. f. 1. Spence Barn, in Ann. Nat. Hist. 2nd ser. vol. xix. p. 136; Cat. Brit. Mas. p. 27. Gossu, Marine Zool. p. 142. Bee 5: ORCHESTIID&. Pulex marinus, Baster, Opuse. Subs. t. 3, f. 7, 8. Cancer gammarellus, Hersst. ii. 129, t. 36, f. 2, 3. Tue eyes are black, irregularly round, moderately large, and situated near the top of the head. The superior antenne are as short as in Talitrus locusta, reaching scarcely to the extremity of the penultimate articulation of the peduncle of the inferior pair. The inferior pair of antennz in full-grown males are scarcely half as long as the animal, they have the first two joints fused into the frontal wall of the head; the last joint of the peduncle is longer than the preceding, and the articulated extremity is as long as the peduncle. The first pair of legs are small, with the penultimate joint shorter than the antepenultimate, and the inferior angle of each is developed into a scaly protuberance; the palm is short, convex, and edged with a row of single hairs: the terminal joint or finger is sharp, scarcely reaching to the extremity of the protuberance. The second pair of legs have the coxee more largely developed, and almost covering those of the first pair: the penultimate joint is large and quadrate, being almost as broad as long: the palm is convex, and not furnished with any important spines or hairs, and armed at the inferior angle with a triangular tooth, which corresponds with the extremity of the finger. The third pair of legs are shorter than the two succeeding, which are subequal. The fourth and fifth joints of the last pair are broadly developed in the mature males, but in the females and young males they are not different from those of the preceding genus. The three posterior pairs of appendages are short and spinous, the posterior being very short. The middle tail-piece is single and pyriform. The Shore-hopper is more compressed laterally than the ORCHESTIA LITTOREA. 29 Sand-hopper. It is of a green colour, and hides beneath stones and vegetable refuse on the shore. The head is smaller than in Talitrus, and the inferior antenne have the flagellum rather longer. The female bears a closer resemblance to Talitrus than the male. The second pair of legs are feeble, and very much like that of Talitrus, from which it can only be distinguished by the form of the hand of the first pair. Orchestia littorea has generally been recorded as asso- ciated with Talitrus locusta, but our experience induces us to attribute the former to rocky, and the latter to sandy, shores. Probably, when there is an approxima- tion in the character of the two kinds of coasts, the species composing the genera may be found to mingle. Montagu on the Devonshire coast, the Rev. George Gordon in the Moray Frith, and Professor Kinahan, at Kilkenny, report the two genera as being found together. But in the long sandy beach in Swansea Bay we never took an Orchestia, though they are to be found round the Mumble Head. Nor have they been taken in Whit- sand Bay, near Plymouth, nor along the sandy beach round Exmouth, in all which places Talitri abound.* It has also been taken by the late W. Thompson in the * We are indebted to Professor Bell, President of the Linnean Society, for the following note on*the present species :—‘‘ Walking along the shore at Bognor, on a stormy day and at high tide, I saw them crawling in great numbers up the sides of the wooden ‘groins’ (a sort of breakwater so called) to which situation they appeared to be driven to avoid the violence of the waves beneath. I found them to consist of what I believe to be the two sizes of one species, many possessing the strong, prehensile hand on the second pair of limbs, and the broad, dilated articulations on the seventh pair belonging to this species, and others without these peculiarities. On the latter alone, and very commonly on these, I found eggs ; they were, in fact, all females, and the others, doubtless, all males ; and as they were found promiscuously together, and none of any other form, I could not but come to the conclusion above mentioned, especially as they agree in all other cha- racters.”” 30 ORCHESTIID A. County of Dublin, and is numerous on the shores of Plymouth Sound, under Mount Batten, where Taltri may also be taken; but the latter appear to occupy a higher coast-line, where the soil is sandy. The eggs of this species are of the same colour as the female, and, after exclusion, the young are carried about by the mother beneath the body. Professor Kinahan informs us that Mr. Williams, of Drogheda, has observed them in Mornington Bay to be phosphorescent. Several specimens have been sent to us as Orchestia Botta, M.-Edw. (a native of the Red Sea), but, taking into consideration the fact announced by Rathke, that the dilated and tubercular character of the posterior pair of legs is only the result of age, we have considered that O. Botte, as a species, is at least doubtful, and, at all events, the supposed British form is only that of a youthful Orchestia of the present species. ORCHESTIA MEDITERRANEA. ol AMPHIPODA. ORCHESTIIDA. SALTATORLIA. ORCHESTIA MEDITERRANEA. Specific Character.—Male.—Second pair of gnathopoda having the pro- podos broad posteriorly, and gradually tapering to a point anteriorly ; palm very oblique, smooth, occupying nearly the whole of the inferior margin ; pos- terior pair of pereiopoda having the meros and carpus broad in mature adults. Female.—First pair of gnathopoda having the propodos long and cylin- drical : the palm short ; the inferior angle but slightly tuberculated. Length of full-grown males about 32 of an inch. O. mediterranea, Costa, Rend. dell, Accad. Sci. Napoli, p. 171, 1853. Spence Barr, Cat. Amph. Brit. Museum, p. 24, pl. iv. fig. 5. O. littorea, Mrunz-Epwarps, Ann. Se. Nat. t. 20, Hist. des Crust. iii. p. 16, Régne An., Edit. Crocarp, Crust. pl. 59, f. 3 (males), fig. 2 b-2 j (details). Raruxe, Fauna der Krym, t. 5, fig. 1-6. Lucas, Exped. dans P Algérie. O. littorea, var., Waite, Hist. Brit. Crust. p. 163. O. levis, Spence Bare, Ann. Nat. Hist. 2nd ser. 1857, xix. p. 1386. Wuurx, Cat. Brit. Mus. Crust. p. 48. oe ORCHESTIID. THe eyes in the male are black, irregularly round, and situated near the top of the head. The superior antennee reach to the extremity of the penultimate joint of the peduncle of the inferior. The inferior antenna are about one-third the length of the entire animal; the last joint of the peduncle is not longer than the pre- ceding; the terminal articulated portion is about the same length as the peduncle. The first pair of legs have the hand not longer than the wrist, and the palm about half as broad again as the diameter of the hand near the centre. The second pair of legs have the hands very large, long, and tapering anteriorly. The inferior margin is slightly concave anteriorly, and no spine, tooth, or angle marks the termination of the palm, which appears to occupy the whole length of the inferior margin. The finger, when closed, reaches to the posterior extremity of the hand, but only impinges against it for about one- third of its length, the rest standing off so as to leave a hollow between the hand and compressed finger. The fifth pair of legs are shorter than the two posterior pairs, the last being somewhat the longest. They are all stout and strong limbs fringed with bunches of stout, blunt, spine-like hairs. The posterior pair have, in mature males, the wrist and the joint preceding it, developed very broadly. The appendages of the tail are short, stout, and spinous. The female is not quite so large as the male, and differs from it but slightly. The first pair of legs are longer, and have the palm shorter, so that the inferior margin of the hand runs parallel with the superior mar- gin. The second pair of legs are small, membranous, and feeble. The finger is reduced to a rudimentary ORCHESTIA MEDITERRANEA. ou state, and articulates remotely from the apex; it is so short that it cannot reach to the extremity of the hand, They are useless as organs of prehension, and appear too feeble to hold, even if they could grasp, any object. The three posterior pairs of legs are nearly equal in their length, being strong and efficient organs for peram- bulation, and fringed with stout hairs. The posterior pair never have the fourth and fifth joints broader than those upon the two preceding pairs of legs. This is a very active and vivacious creature. It hops, when disturbed, to a considerable distance, taking a direction always towards the sea. The female, from its compressed form, and the fact that it can move the legs only in a vertical plane, falls upon its sides and wriggles along, until it intends to give a spring, when, having managed to support itself upon its feet, with the pos- terior portion of its body doubled up close beneath, it boldly strikes out its tail with a force which sends it several feet. By this means the caudal stylets and spines are often broken or worn away. The male, by means of the warty excrescence upon the last pair of legs, is en- abled to walk without falling upon its side. This en- largement of the middle joints of the last pair of legs is not common to all the species of this genus, and in those to which it belongs, it is developed only in the adult state, and, according to Rathke, increases with age. It is not a complete enlargement of the whole limb, but one of breadth of a part only; the leg existing in its normal size as a ridge upon the inner surface. The female of O. mediterranea, according to Risso, car- ries egos many times during the year. The eggs of this species are in an early stage of a deep purple colour, but the young, when they first quit the pouch of the parent, are of a bright*orange. This species, particularly the D 34 ORCHESTIIDA., female, bears a close resemblance to that of O. littorea, agreeing with it both in colour and habits ; but we are not sure that it is so common, or that they are found associated together, although frequently confounded with each other. Edwards, Rathke, and Lucas have so mistaken it, sup- posing it to be Montagu’s species, as we have ascertained from an examination of the typical specimens in the British Museum and the Museum of the Jardin des Plantes.* We first took the species under a stone far above high- water mark in Langland Bay, near Swansea. It was so far from the shore that the grass grew all round the stone, beneath which it was associated with terrestrial Isopoda (Oniscide). We have also taken it on the shore near the Bailey Lighthouse on the Hill of Howth, in Dublin Bay, in the month of October sparingly, but it was found in numbers, and of various sizes, in the month of January, among gravel on the beach of Rough Island, Shangford Lough, by Mr. W. Derragh, by whom it was communicated to the late Mr. W. Thompson, These specimens are now (together with his whole collec- tion) in the Museum of Belfast, and we have much pleasure in returning our thanks to the trustees of that excellent institution for the use of the whole of the Edriophthalma collected by that late eminent Irish na- turalist. Professor Kinahan has taken it seven feet above tide-mark, mixed with Oniscus murarius, O. fossor, Arma- dillo vulgaris, and Porcellio scaber. These are the only recorded British habitats, a circumstance that arises most probably from the species being mistaken for O. littorea, * We take this opportunity of expressing our obligation to the officers of both these institutions for the courteous reception we have invariably met with from them, the willingness with which every specimen has been placed at our disposal, and the forestalment of our wants in facilitating their exami- nation. ORCHESTIA MEDITERRANEA. 35 since we are enabled to trace it along the coasts of the Mediterranean (according to Edwards, Costa, and Lucas) to the shores of the Crimea (Rathke). The following vignette of Caswell Bay is from the pencil of our friend Mr. Lewis Dillwyn, M.P. for Swan- sea. Caswell Bay is of a similar character to, and only separated by a ridge of mountain limestone from, Lang- land Bay, where the species was first taken, 36 ORCHESTITD/. AMPHIPODA. ORCHESTIID A. SALTATORIA, ORCHESTIA DESHAYESII. Specific character.—Second pair of gnathopoda, having the propodos tapering, the palm occupying nearly the entire length of the inferior margin, defined by a large tooth at the inferior angle. Length $3 of an inch, Orchestia Deshayesii. Aupourn, Explic. Savigny, Crust. Egypte, -pl. xi. fig. 8. Minne-Epwarps, Crust. iii. p. 18, Ann. Se. Nat. xx. p. 361. Wurrts, Catal. Brit. Crust. p. 48. Popul. Hist. Brit. Crust. p. 163, Spence Bare, Ann, Nat. Hist. February, 1857, Eyes black, large, irregularly round. Superior an- tenne reaching to half the length of the penulti- mate joint of the peduncle of the inferior. Inferior antenne about half as long as the body of the animal. The last joint of the peduncle as long again as the penultimate, and nearly three times as long as the arti- culated termination. First pair of legs small, the palm but little broader than the hand, the inferior angle ob- tusely rounded: the hand not so long as the wrist: wrist with a small tubercle near the centre of the inferior margin. Second pair of legs with the hand large and long, broad near the wrist, and tapering towards the or ( ORCHESTIA DESHAYESII. 9) finger: palm occupying nearly the whole of the inferior margin, with a large tooth at the inferior angle, against which the extremity of the curved finger impinges when closed. The coxa of the fifth pair of legs is bilobed, but isnot quite so deepas the coxa of the preceding pair. Fifth pair of legs shorter than the sixth and seventh. This species was first taken by Savigny in Egypt, when he visited that country with the first Napoleon. A spe- cimen in the British Museum was taken on the British coast. One in the Museum at the Athenzeum, Plymouth, was taken by the late Dr. Edward Moore, under Mount Batten, in Plymouth Harbour. An English specimen of an unknown locality has been for many years in Mr. West- wood’s collection, and Professor Kinahan, who states that it is local and rare, has sent us specimens from Carrick- fergus. In its general form it is less compressed than O. littorea. The widely separated recorded habitats in- duces us to believe that, like O. mediterranea, it has hitherto been overlooked, a fact that has been too common in this order of Crustacea. The accompanying vignette of Mount Batten is from the pencil of our friend Mr. Philip Mitchell, of the New Water Colour Society. 38 ORCHES'TIID. AMPHIPODA. ORCHESTIIDA. SALTATORIA. Genus—ALLORCHESTES, Dana. Dana, United States’ Expl. Exped. p. 883. Proc. Amer. Acad. Arts and Sci. ii. p. 206. Amer. J]. Sci. 2nd ser. vill. p. 136. Generic character.—Like Orchestia, but the superior antenne are longer than the peduncle of the inferior. Maxillipedes un- guiculate. Carpus of the second pair of gnathopoda inferiorly and anteriorly produced. Telson single. THE superior antenne are at least as long as the peduncle of the inferior. The inferior antenne have the two basal articulations not so closely incorporated with the head as in Orchestia; they are, moreover, fur- nished with a small olfactory denticle. The mandibles are without any palpiform appendage. The foot-jaws terminate in a sharp point. The two anterior pairs of legs have subchelate hands. Coxe of the fifth pair of legs shorter than those of the fourth. Caudal appen- dages short and robust. Dana established this genus for the reception of cer- tain species of Amphipods which had been attributed by authors to various genera. It more nearly resembles Orchestia than any other genus, but is very easily dis- tinguished from it by the length of the superior antenne. Upon first consideration, it would seem that this slight difference could scarcely be of sufficient importance to warrant a generic separation. Closer inspection, how- ever, shows that it is associated with some important changes both in the structure and habits of the animals. ALLORCHESTES. 39 The inferior antennz have the basal articulation not so closely fused with the head as in Orchestia, and a small olfactory denticle is visible. The foot-jaws ter- minate in a sharp curved nail. The hands of the first two pairs of legs are subchelate in both sexes. The an- terior pair are small, the second are generally large and powerful in the male. In the female, though occasion- ally smaller than those of the male, they are never rudi- mentary, and are generally developed upon the type of the male, except that the wrist is produced along the inferior margin of the hand. The first joint (or coxa) of the first four pairs of limbs is large and squamiform, being nearly as deep as the body of the animal. The first joint of the fifth pair of legs is much shorter than that of the preceding pairs. The caudal appendages are short and stout, the posterior being unibranched. In habits as well as in organization, Allorchestes occu- pies a position between Orchestia and Gammarus. Itisa littoral genus, dwelling generally under weed upon the shore, and in pools left by the sea, One species only, A. medius, is recorded by Dana as having been taken by the dredge in two separate localities, in several fathoms of water. The geographical range of this genus is very wide. It is found throughout the temperate and subarctic zones of both hemispheres. Under the name of Enone Risso has described (Eu- rope meridionale, p. 96) a genus which we believe to be identical with the present; but the description is so des- titute of distinctive characters, that it is not sufficient to warrant its acceptance even as a synonym. 40 ORCHESTIIDA, AMPHIPODA. ORCHESTIID 4. SALTATORIA. ALLORCHESTES NILSSONII, Rathke. Specific character.—Matx. Superior antennz as long as the peduncle of the inferior. Inferior antenne one-third the length of the animal. Second pair of gnathopoda larger than the first. Propodos ovate, large, with convex palm and an obtuse point at the inferior angle. Length 5, of an inch. Amphithie Nilssontti Ravuxe, Beit. zur Faun. Nory. in Nov. act. xx. p. 264 co. +3 Prevostit 3 5 l. c. p. 81, pl. 4, fig. 5 (not of Minne Epwarps). lLinsesporc, in Ofyers, af Kongl. Vetensk. akad. Forhandl. 1851, p, 22. Allorchestes Nilssonti, Bruzevius, Bidrag. till Kim. om Skand. Amph, Gam. p. 35. Spence Bare, Cat. Amp. Brit. Mus. p. 38, pl. vi. fig. 4. A Danai, Svence Bate, Rep. Brit. Assoc. 1855, p. 57. Ann. Nat. Hist. Feb. 1857. Wuutsr, Hist. Brit. Crust. 1858, p. 163, ALLORCHESTES NILSSONII. AA THE eyes are not large, but round and black. The superior antenne reach to the extremity of the peduncle of the inferior. The inferior antenne are about one- fourth the length of the whole animal, with the peduncle about half the length of the antenne. The two basal joints are closely incorporated, but not fused, with the head. The mandibles are short, denticulated at the margin, furnished with a secondary plate, but destitute of any palpiform appendage. The foot-jaws are fur- nished at the apex with a sharp nail. The squamiform plates are three, two important, the third less so, fringed with short hairs. The first pair of legs have the hand oval, or nearly so, when the finger is shut: the palm is convex, and an obtuse tooth is placed just beyond the apex of the shut finger: the wrist is moderately pro- duced inferiorly. The second pair of legs have the hand much more developed, but formed upon the same type as the first. All the other pairs of legs terminate in curved pointed fingers. The squamiform basal joint of the four anterior pairs of limbs is as broad as deep, and nearly as deep as the respective segment of the body to which it is at- tached. Those belonging to the three posterior pairs are much shorter. The caudal appendages are short, stiff, and furnished with short, spine-like hairs. The middle tail-piece is single and small. This animal has, no doubt, been mistaken for the young of Orchestia littorea, to which it bears a general resemblance; but it can readily be distinguished by the length of the superior antenne, which are rather stiff in their general appearance. The microscopic structure of the skin shows a distine- tion (although not a very great one) from that of Tualitrus and Orchestia. The t-markings are somewhat more nu- 42 ORCHESTIIDA. merous, and differ slightly in shape. The whole structure is dotted with granular markings, but no trace of the original cell-formation is apparent. sk fitims The hairs, which are scattered over the legs, though formed upon the same plan as in Talitrus, terminate in a slight, but sharp point; and the small secondary branch has a peculiar bead-like appearance. The habitat of this animal is along the coast, between the ordinary high water-mark and that of spring-tides. In places where it is found, it appears to be more abun- dant than the Orchestie. It is of a dark green colour, and, when dead, may easily be distinguished amongst many others by a metallic lustre. We have received specimens from Penzance, sent to us by Mr. George Barlee and Mr. W. Webster; from Moray Frith, by the Rev. Geo. Gordon; from Falmouth and Tenby, by Mr. W. Webster; and have taken them ourselves on the shores of Plymouth Sound. As it was from this species that our knowledge of the genus was first obtained, we named it originally after the illustrious American carcinologist, by whom the genus was founded; but, upon further examination, we believe it to be identical with Amphithie Nilssonii, of Rathke, and which he first regarded as identical with Amphithée Prevostu of Edwards. ALLORCHESTES IMBRICATUS. 43 AMPHIPODA., ORCHESTIIDA. SALTATORIA ALLORCHESTES IMBRICATUS. Specific character.—Dorsal median line slightly carinated and imbricated. The inferior antennz more than twice the length of the superior. First pair of gnathopoda very much smaller than the second pair. Length J, of an inch. Allorchestes imbricatus, Srrnce Bare, Report Brit. Assoc. 1856, p. 57. Ann. Nat. Hist. Feb. 1857. Cat. Amph. Brit. Mus. p. 41, pl. vi. fig. 8. Waurre, Pop. Hist. Brit. Crust. 1858, p. 164. THE eyes of this species are small and round. The peduncle of the superior antenne is quite half the length of the antennz, and reaches nearly to the extremity of the peduncle of the inferior. The first pair of legs have the hand more than as long again as broad; the wrist is but slightly produced inferiorly. The second pair of legs have a very large and powerful hand, with the palm slightly oblique, and the finger fitting into a groove. The hand is broader posteriorly than at the palm. The four anterior pairs of squamiform coxz are large, but scarcely so deep as the respective segments of the body to which they are attached. Those of the fifth pair of legs are about half as deep as the preceding, and are 44 ORCHESTIIDA. formed of two equal lobes. The second scale-like joint of the last three pairs of legs is oval. The caudal ap- pendages are short and strong. The animal generally is longer and more compressed than A. Nilssonii. The dorsal ridge is slightly elevated into a carina, which is most conspicuous towards the pos- terior limit of each segment. This gives to the animal, when viewed laterally, an imbricated appearance, from which circumstance we have taken the name, and by which the species can easily be determined from any other known British form. A. imbricatus appears to be rather local. The first specimens that we received were from Penzance, where they were taken by Mr. George Barlee, between tide- marks. In company with Professor Kinahan we have found them on the Breakwater at Plymouth, where they live in small pools Jeft in the holes worn by the wash of the sea in the surface of that stupendous work. We found many individuals, and they appeared to be the only species of Amphipod that existed there. The colour was a bluish- grey, but a few were almost black. The following vignette is a sketch of the Western end of the Breakwater by Mr. Philip Mitchell, of Plymouth. NICEA, 45 AMPHIPODA., ORCHESTIID A. SALTATORIA, Genus—NICEA, Nicouer. Nicka, NIcoLET in Gay’s Chili, vol. iii. p. 237, 1849, GaLAnTHIs, Sprnce Barz, Brit. Assoc. Report, 1855, p. 57; Ann. Nat. Hist. 1857. Generic character.—Antennee small, subequal ; both pairs of gnathopoda subchelate. Coxe of the third pair of pereiopoda much shorter than the preceding. Telson deeply cleft. THE antenne are small and slender, being scarcely one- fourth the length of the animal, and the superior are almost as long as the inferior, The mandibles are longer than deep: they are furnished with a secondary incisive plate; and a tubercle marks the position of the absent appendage. The foot-jaws have squamous plates arising from the second and third joints, which terminate in sharp stiff hairs, or spines. The first two pairs of legs are formed upon the same type, and are subchelate. The first four pairs of legs have the squamiform basal joint as deep as the body, the fifth much shorter. The three posterior pairs of legs are nearly equal in length. The middle tail-piece is deeply cleft or divided. This genus differs from Allorchestes in the approximate length of the antennz, which appears to be attributable rather to the shortness of the inferior than the length of the superior, and also in the middle tail-piece being divided. The genus Hyale, of Rathke, seems to approach near to this, the only distinction being in the last pair of 46 ORCHESTIIDA, caudal appendages, which are unibranched throughout this family, but which are doubly branched in Hyale. Only two species of this genus are known, and these are from habitats widely asunder: Nicea Lucasii, inhabit- ing the western coasts of South America, and our own British species. The following vignette represents a village of fisher- men’s huts in the Island of St. Kilda. They are built upon the plan of the houses of the Ancient Britons, and are within lined with the feathers of sea-fowl. NICEA LUBBOCKIANA. 47 AMPHIPODA. ORCHESTIID&. SALTATORIA. NICEA LUBBOCKIANA,. Specific character. —Antenne short, subequal in length. Gnathopoda sub- equal in size : palm slightly oblique. Telson deeply cleft. Length 3, of an inch. Galanthis Lubbockiana, Spence Barr, Brit. Assoc. Report, 1855, p. 57. Ann. Nat. Hist. 1857. Wurtr, Popul. Hist. Brit. Crust. p. 164. Nicea 5 Spence Bate, Cat. Brit. Mus. p. 51. THE eyes are round; the anterior pair of antennz are scarcely longer than the head. The inferior is scarcely as long as the superior. The first pair of legs are sub- chelate ; the hand is longer than broad, the palm straight, oblique, fringed with fine cilia; the inferior extremity terminates in an obtuse tooth; the inferior margin is 48 ORCHESTIID A. parallel with the superior; the wrist is short and in- feriorly produced. The second pair of legs are formed upon the same type, and are scarcely larger than the first. The walking legs are all short and stout, terminating in a sharp curved finger; the caudal appendages are very short and strong, and fringed with but few spines; the terminal appendage is deeply cleft. The animal is not much compressed, and all the seg- ments of the body are uniform in length: a circumstance which enables it to roll itself into a more perfect sphere than Amphipods generally do—a fact by which it may readily be detected amongst a number of other species. We have never seen any of this individual species alive; but in dead specimens the eyes lose all colouring matter. The antenne are short and slight, gradually de- creasing in diameter from the base, the first joint being the largest, the rest gradually smaller, and the articuli of the flagella lessen in the same degree, so that there is no decided distinction between their respective peduncles and flagella. The walking legs are all strong and short, the ante- penultimate being shorter than the two posterior. They are all furnished at the extremity of the foot with two stout spines, curved at the apex, and serrated on the sides facing the finger against which they impinge when closed (kh). The animal generally is free from hairs or spines, some small ones, however, exist upon the antenne, and a few others may be found upon the legs, short and some- what pyriform in shape, with the apex cleft into two equal parts (A). The integument under the micro- scope shows the tT-like mark peculiar NICEA LUBBOCKIANA. 49 to the family, somewhat modified from the previous genera, and as exhibited in the preceding cut :—The skin is also granulated all over, and is interspersed with mi- nute solitary hairs. We have received many specimens of this species from Falmouth, sent by Mr. W. Webster; from Penzance by Mr. Harris, and Mr. G. Barlee; and from the coast of Northumberland by Mr. Joshua Alder. We have named the species in compliment to our friend John Lubbock, Esq., F.R.S., &c., whose name is so inti- mately associated with Crustacea, and to whom we take this opportunity of acknowledging our obligations. The accompanying vignette is by the pencil of Mr. Sydney Whiteford. 50 AMPHIPODA. Tribe —NATATORIA. In this tribe the superior antenne are always longer than the peduncle of the inferior pair. The third pair of caudal appendages reach as far as the extremity of the second pair. The hairs upon every part of the animal are generally slight and flexible, never short, stiff, and double-headed, as found upon the animals in the tribe SALTATORIA. The habits of the animals in this tribe are aquatic, the most littoral living at half-tide under weeds and stones, but by far the greatest number of the species are found in the water. The common mode of progression is by swimming. This act is performed by the constant play of the three pairs of limbs succeeding the last pair of feet, which thus receive the common synonym of natatory legs. These are long, multiarticulate, pliable, and feathery ; they brush the water with a constancy equal to that of the fins of a fish in motion, and propel the creature with considerable velocity. It is from this circumstance that the name of the tribe has been derived. If acci- dentally thrown upon dry land, they have neither the power to walk nor to leap—they consequently wriggle along upon one side, a circumstance which has obtained for them the familiar cognomen of “ sea-screws.”’ ‘This tribe contains but a single family. Fam.—GAMMARIDA. THE antenne are well developed, and generally sub- equal. The inferior pair are inserted in a notch at the infero-anterior angle of the cephalon, with which, how- GAMMARIDA. 51 ever, they are not soldered. The maxillipeds are un- guiculate. ‘The four anterior pairs of cox are largely developed. This family consists of several subfamilies, which differ from each other in more or less important points. The superior antennz are generally subequal to the inferior, and bear a secondary appendage at the base of the flagellum. This peculiarity, although occasion- ally absent in the adult state, is, we believe, invariably found in the young. One or both pairs of the fore-legs or arms have subchelate hands.* Sub-family.—_STEGOCEPHALIDES. Antenne more than one-fourth the length of the animal, sub- equal. Coxe of the second pair of gnathopoda, and of the first and second pairs of pereiopoda monstrously developed. In some genera the coxe of the first pair of legs are rudimentary, or, at least, not developed into scales ; whereas the second is always large, covering the pre- ceding when not squamiform. The hands are subchelate, and the caudal appendages are styliform. The middle piece of the tail is always single. This sub-family was established by Dana under the name of STEGOCEPHALIN&, for the reception of Kroyer’s genus Stegocephalus. But there are several other genera which evidently fall within its definition. The principal feature, and one easily recognizable, is, the large size of cox of the first two pairs of walking legs. These are so monstrously developed, that the animal has the power, when rolled up, of protecting, under this shield-like * By a subchelate hand is meant one in which the finger folds upon the hand, but in which the inferior angle of the palm is not produced into an an- tagonistic thumb, E 2 52 GAMMARIDA. structure, the head, much of the posterior part of the body, and all the legs and other appendages. In the absence of an articulated appendage to the mandibles, and the unibranched termination of the posterior pair of caudal appendages, some of the genera approximate to the ORcHESTIID#, whereas others gradu- ally approach the forms of the next sub-family of the GAMMARID&. There are but two genera which represent this sub- family upon the British coasts, all the rest being exotic. Some species of Stenothée, a genus that differs from Montagua in no-very marked degree, found upon the coast of the United States, bear a representative rela- tion to the British forms. MONTAGUA. 53 AMPHIPODA. STEGOCEPHA LI DES. NATATORIA. Genus—MONTAGUA. Montagua, Spence Bats, Report Brit. Assoc. 1855, p. 57. Synopsis Brit. Amph. Ann. Nat. Hist. 1857, xix. p. 137. Cat. Amph. Brit. Mus. p. 54. Wurre, Pop. Hist. Brit. Crust. p. 166. Leucothoé, Kroyur (not Luacn), Nat. Tids. iv. p. 141 (2), i. p. 539, 1845. Generic description. Antenne subequal. Superior pair with- out a secondary appendage. Gnathopoda subchelate. Coxa of second pair covering those of the first. ‘Telson entire. THE antenne are nearly equal in length: the superior do not possess a secondary appendage. The mandibles are without an articulated appendage. The foot-jaws are without squamous plates, and terminate in a hook. The two anterior pairs of legs are unequal, subchelate; the first pair having the first joint not squamiformly developed; the second pair are larger than the first, having the first joint squamiformly developed to con- siderable dimensions, and overlapping that of the first pair. The remaining legs are subequal. The coxe of the three last pairs are small. The caudal appendages are styliform, the last pair having but a single branch, which is double-jointed. The terminal scale is squamous and entire. This genus is named after Colonel Montagu, who was a worthy pioneer in this branch of Zoology, and the discoverer of the first species. 54 GAMMARIDA, AMPHIPODA. STEGOCEPHALIDES. NATATORIA. MONTAGUA MONOCULOIDES. Specific character. Second pair of gnathopoda having the propodos twice as long as broad, palm oblique, smooth, slightly convex, defined by a very obtuse angle armed with two sharp short spines. Length, 3, of an inch. Cancer (Gammarus) monoculoides, Montacu, Trans. Linn. Soe. vol. xi. p. 4, pl. ii. fig. 3. Montagua monoculoides, Spence Batu, Rep. Brit. Assoc, 1855, p. 57. Synop. Brit. Amph. Ann. Nat. Hist. 1857, xix. 1387. Cat. Brit. Mus. p- 55, pl. viii. fig 4. Typhis (+) monoculoides, Mitye-Epwarps, Ann. Sci. Nat. t. xx. Aug. 1830. Wuutsr, Cat. Brit. Crust. in Brit. Mus. 1850, p. 58. Gossz, Mar. Zool. p. 140, fig. 252. Tue head produced anteriorly into a small depressed rostrum. The back smooth. The eyes are round, and of a red colour. The superior antenne have each joint of the peduncle successively reduced in size, the flagellum MONTAGUA MONOCULOIDES. 55 is composed of many small jointlets,* each having several cilia. The inferior pair are shorter than the superior, and less robust. The mandibles are long and narrow, and furnished with a serrated cutting margin. The outer pair of foot-jaws have the third and sixth joints respectively longer than the fourth and fifth conjoined: the seventh terminating in a sharp point. The first pair of legs are short and slender, having the first joint not developed into a scale; the hand is longer than the wrist, and developed in the same form as that of the second pair; the palm is very oblique, and defined from the inferior margin by a very obtuse angle. The second pair of legs have the first joint large, scale-like, narrow, increasing in breadth gradually from the body, and reaching so far in front as to cover the appendages of the mouth; the wrist is short; the hand long, ovate ; the palm oblique, slightly convex, and de- fined by an obtuse angle, armed with two short sharp spines, against which the apex of the slightly-curved finger impinges. The third pair of legs have the first joint more largely developed than that of the preced- ing pair of limbs, and with the inferior margin fringed with minute equidistant cilia, situated within the edge ; the foot is slightly bent, having the margins parallel, and armed upon the inner distal extremity with two short sharp spines, against which the finger impinges near the base, thus giving the foot a prehensile capa- bility. The fourth pair of legs are like the third, but have the first joint still more largely developed, being not only produced anteriorly, parallel with the preceding, but extending as far back as the penultimate pair of legs. * The term jointlet, or articulus, is used to indicate its distinction from a joint : some authors have described the flagellum as a single joint, and others as if every articulus was a distinct joint. 56 GAMMARIDA. The inferior margin of this appendage is, like the one last described, fringed with a row of equidistant solitary cilia. The fifth, sixth, and seventh pairs of legs are uniform, except that the second joint of the fifth pair is not developed like a scale, which is the case with the second joint of the two other pairs. Their first joints are small, almost rudimentary, and exhibiting but slight traces of their scale-like character. In all other respects the last three pairs of legs resemble in appearance those of the two preceding pairs, with the exception of being affixed in a reversed position, according to the common type of the order. - The three pairs of swimming appendages are long and slender. The three pairs of caudal appendages are strong, stiff, and pointed; the penultimate is shorter than the other two. The last pair has its branch with the apical joint nearly as long as the preceding. The terminal scale is ovate, fringed with three or four short hairs. The colour of this species is white, or flesh-colour, marked with a large blotch of bright crimson on the back and side, and with a few darker spots of the same colour, as represented by the shading in the accompany- ing figure. A single specimen that we obtained from the neighbourhood of the Eddystone Lighthouse was marked all over with red spots. It only appeared to differ from the present species in having the palm of the hand of the second pair of arms slightly crenulated. It appears not to be uncommon on our shores: it is a sublittoral species, and exists probably all round Europe, being found beneath stones in pools, near low water at spring-tides. It has the capability of rolling itself very perfectly within the defensive armour provided by its largely- developed coxe. MONTAGUA MONOCULOIDES. on The first specimen, found by Colonel Montagu and still preserved in the British Museum, is thus rolled up, which circumstance, together with Montagu’s incomplete figure in the Linnzan Transactions, may account for the circumstance of its so long having escaped the analysis of inquiring carcinologists. We have carefully examined the type in the British Museum, and have no doubt of the correctness of our identification of it with the spe- cimen represented in our figure. We may, however, observe, that the terminal joint of the peduncle of its lower antenne is more decidedly elongated, the spines on the under-edge of its hands stronger, and the two divi- sions of the middle appendages of its tail longer. This specimen was taken from Montagu’s favourite hunting- ground, Salcombe Harbour, Devonshire. We have also received specimens from the following localities:—Falmouth and Tenby, Mr. Webster. Pen- zance, Mr. Harris and Mr. G. Barlee. Moray Frith, Rev. Mr. Gordon. Skye and Shetland, Mr. Barlee. Plymouth, Mr. Howard Stewart, and C.S.B. Sligo and Belfast Bay, Ireland, Mr. W. Thompson. 58 GAMMARID. AMPHIPODA. STEGOCEP HALIDES. NATATORiA. MONTAGUA MARINA. Second pair of gnathopoda having the propodos long and tapering, with the palm nearly straight, occupying almost the entire length of the inferior margin. ; : Length, 34 of an inch. Montagua marina, Spence Bate, Brit. Assoc. Rep. 1855, p. 57. Synopsis Ann. Nat. Hist. 1857, xix. 137. Cat. Amph. Brit. Mus. p. 56, pl. viii. fig. 5. Wuurre, Pop. Hist. Brit. Crust. p- 166. THE eyes are round and red. ‘The superior antenne are half the length of the animal. The first joint of the peduncle is as long as the head; the second joint is quite as long as the first, but not so stout; the third is very small, both in length and breadth. ‘The flagellum is longer than the peduncle. The inferior antennz are nearly as long as the superior; the penultimate joint MONTAGUA MARINA, 59 of the peduncle reaches beyond the extremity of the peduncle of the superior. The last joint is rather more than half the length of the preceding, and the flagellum is not longer than the last joint of the peduncle. The mandibles are long, narrow, and furnished with a minutely serrated cutting margin. It is also furnished with a mi- nute secondary moveable plate having a serrated edge. This plate we believe to be common to the genus, but is not figured in the preceding species, from the probable fact that it exists only upon one mandible, the other being without it, as shown by Mr. Westwood’s dis- sections, published by Professor Bell, to be the case in Stegocephalus ampullus, the typical genus of this subfamily--where it exists upon the left mandible onlv. The pair of foot-jaws have all the joints subequal, the sixth being slightly longer than any of the others. The first pair of legs are short and slender, having the fourth joint anteriorly produced into a considerable pro- cess beneath the fifth. The fifth, or wrist, is nearly as long as the sixth, or hand, which is of a long elliptical form, having the palm convex, not defined, but armed with a few cilia. The second pair of legs are much longer, larger, and more powerful than the first. They have the fourth and fifth joints very short, but both anteriorly ard inferiorly produced to an angle. The hand is long; the upper margin forming an arched line continuous with that of the wrist; the palm runs diagonally with the axis of the hand, nearly straight to its base beneath, where two small tubercles, armed with a single blunt spine, carrying a small subapical bristle, define its limits. Throughout its entire length the palm is furnished with a row of equidistant solitary cilia. The finger is as long as the palm, somewhat curved, and tapering to the point, which, when closed, 60 GAMMARIDA. impinges against the two small teeth at the base of the palm. The animal, in other respects, closely re- sembles M. monoculoides, except that the terminal scale of the tail is more pointed. The colour of the animal, when alive, is yellowish, or pale flesh-colour, several parts of the body and coxz marked with faint blotches of light rose, or pink. The structure of the integument is very free from any decided markings; but the surface is in different parts furnished with very minute cilia, which are nowhere thickly planted. We have received specimens of this species from the coast of Northumberland, from Mr. Joshua Alder; also from Banff, Mr. Edward; and from Macduff, from Mr. Gregor ; we have found it ourselves amongst some trawl refuse brought to us from near the Eddystone Light- house. We have also received a specimen, which we consider to be only a variety of this species, from the coast of Piedmont, collected by Mr. Gwynn Jeffreys: it varies from the type in having the palm of the second pair of legs somewhat less than the entire length of the hand. This specimen was taken upon the shore, whereas all those recorded as British have never been taken in less than ten fathoms of water—a circumstance not of much importance in itself, but as adding to the testimony of the late Professor Edward Forbes, that species taken in the deep sea in northern latitudes, when they exist near the equator, inhabit shallow water. MONTAGUA ALDERI. 61 AMPHIPODA. STEGOCEPHA LIDES. NATATORIA, MONTAGUA ALDERI. Specific character. Second pair of gnathopoda having the propodos short ; palm serrated near the base of the dactylos, and deeply emarginated near the inferior angle, which is produced to a sharp point. Length, 3, of an inch. Montagua Alderti, Spencer Baten, Rep. Brit. Assoc. 1855. Synop. Brit. Amph. Ann. Nat. Hist. 1857, xix. 187. Cat: of Amph. Brit. Mus. p.57, pl. viii. fig. 6. Wuitr, Pop. Hist. Brit. Crust. p. 166. THE eyes, as in all the other species of the genus which we know, are round and red. The superior antenne are nearly one-half the length of the animal, having the flagellum rather longer than the peduncle. The inferior antenne are longer than the superior, and the peduncle reaches nearly to the extremity of the superior antenne ; the two last joints of the peduncle are nearly of equal length, the last being rather the shorter, and the flagellum is not longer than the last joint of the peduncle. The first pair of legs are slender, and have the fourth joint 62 GAMMARIDA, inferiorly produced to nearly half the length of the carpus, and furnished at the apex with a few hairs, some of which are straight, while others are of a form which appears to be peculiar to this species, consisting of a kind of plumose tuft, or brush mounted on a stalk (fig. “’). The wrist is long, and increases in breadth towards the extremity. The hand is shorter and narrower than the carpus; the form is long-ovate, having the upper and lower margins slightly convex; the palm is short, oblique, and imperfectly defined; the finger is much longer than the palm, and is nearly straight, a circum- stance which demonstrates it to be a feeble organ of prehension. The second pair of legs are much more powerful and longer than the first. The wrist is short, and the hand is quadrate, being but a little longer than broad; the palm is oblique, and serrated with coarse, irregular, blunt teeth on the half nearest the base of the finger, and deeply emarginate towards the inferior angle, which is produced to a sharp point. The finger is arched, and impinges, when closed, into the emargination of the palm, which, from the irregular form of the latter, must enable it to hold securely any object in its grasp. The specimen from which our figure was taken enabled us to see the muscles within the organ, proving that the ex- tensor is smaller and much less powerful than that which forces the finger into contact with the palm. The other legs are all of the same length, and are tolerably strong. The second joints of the last two pairs are broadly de- veloped, and have the posterior margin scalloped ; this is also the case with the fourth joints of the same legs, which are posteriorly produced to a blunt downward point, a small hair springing from the depression between every scallop. The feet are much curved, and have the anterior margins armed with short hairs, or rather spines, MONTAGUA ALDERI. 63 which are evidently of service in assisting the animal in securely grasping the weed, or stalks of zoophytes, as it rambles through its submarine gardens. ‘The fingers are short and sharp. The caudal appendages do not appear to differ materially from those of the preceding species. This animal, when alive, is straw-coloured, striped with bands of rose, one occurring in each segment through the body; these are continued down the sides of the animal, but grow fainter and less persistent towards the posterior extremity of the animal. The first specimen was sent to us by Mr. Joshua Alder (in compliment to whom the species is named), and was taken by him on the coast of Northumberland, off Cullercoats; whence we have also received it from the Rev. A. Merle Norman. This spot having been rendered classic to naturalists as the field of the re- searches of various eminent observers, we append a vignette of it from the pencil of Mr. Alder himself. 64 GAMMARID&., AMPHIPODA. STEGOCEPHALIDES. NATATORIA. , MONTAGUA POLLEXIANA. Specific character. Second pair of gnathopoda having the propodos as long again as broad ; palm advanced, deeply notched just within the inferior angle, which is produced into a tooth, internally concave. Length, } inch. Montagua pollexiana, Spence Bate, Brit. Assoc. Report, p. 57, 1855. Synop- sis, Ann. Nat. Hist. 1857, xix. 1387. Cat. Amph. Brit. Mus. p. 57, pl. lx. fig. 2. Wuurrr, Pop. Hist. Brit. Crust. p. 167. Tuer eyes are small, round, and probably red; we have, however, only seen dried or dead specimens, from which all colour rapidly passes away. The superior antennz are nearly two-thirds the length of the body, having the first joint of the peduncle longer than the head, the second joint a little shorter than the first, and the third small, not being distinguishable from the articuli of the flagellum. The inferior antennz are MONTAGUA POLLEXIANA. 65 shorter than the superior, with the peduncle extending as far as the middle of the flagellum of the superior. The last joint of the peduncle of the inferior pair is rather longer than the preceding, and the flagellum is rather shorter than the last joint of the peduncle. The first pair of legs are slender, the fourth joint of which is but slightly produced anteriorly below, where it is tipped with long hairs ; the wrist is very long, and fringed upon the lower side with fine hairs; the hand is much shorter, scarcely more than half the length of the wrist, it is also narrower; it increases in width towards the palm, which is short and imperfectly defined. The finger is as long again as the palm, and nearly straight. The second pair of legs are longer and stronger than the first; the hand is twice as long as broad, the upper and lower margins are imperfectly parallel, the form of the organ is therefore oblong-quadrate; the palm is advanced, smooth, and fringed with a few solitary hairs; just within the inferior angle is a narrow deep cleft or notch, extending in depth to about one-third the length of the hand, giving to the inferior angle of the palm, which is slightly produced in advance, the appearance of a strong thumb, hollowed upon its internal surface. From this peculiar character the specific name of the animal is derived. The finger is scarcely as long as the palm, and impinges throughout its entire length against that part of the joint. The other legs do not appear to differ much from those of M. monoculoides, except in the unimportant circumstance that the posterior margin of the second joints of the two posterior pairs of legs are not crenulated, and the spines that arm the distal ex- tremity of the feet are crenulated upon one side, and curved at the tip into an imperfect hook, with a small subapical process in the opposite direction, the apices i 66 GAMMARIDA, nearly meeting. The caudal appendages have their branches nearly equal, whilst the last has the base pro- duced into a sharp point at the upper distal extremity. The terminal scale is lanceolate. We have not been able to determine the colour of this species, which is the largest of the genus, not having seen any living or fresh specimens. The surface of the skin is irregularly covered with very small sharp hairs, so minute that they can only be detected by a high power of the microscope. This species is nearly as large again as either of the others, and its geographical range 1s also considerable. We have received specimens from our valued friend and correspondent, Mr. Geo. Barlee, who has taken them with the dredge at St. Ives, on the north coast of Corn- wall, and also from the Shetland Islands. We have also received it from the coast of Northumberland, from the Rev. A. M. Norman. It also occurs, not uncom- monly, in Berwick Bay, whence we received specimens many years since from the late lamented Dr. George Johnstone. Beneath is a sketch of Whitby Rocks, on the coast of Northumberland, from the clever pencil of Miss M. Hancock. DANATA. 67 AMPHIPODA, STEGOCEPHALIDES. NATATORIA. Genus—DANATA. Danaia, Spence Barn, in Ann. Nat. Hist. 1857, xix. p. 137. Generic character. Antenne subequal. Superior antenne with- out secondary appendage. Mandibles destitute of a palpiform appendage. First pair of gnathopoda simple. Second sub- chelate. Telson single. THE superior antennz are without a secondary ap- pendage. The mandibles have no appendage. The first pair of limbs are slender, and terminate in a straight, sharp finger, which does not impinge against the under- side of the preceding joint. The second pair of limbs are larger than the first, and have a subchelate hand. The coxa of the first pair of limbs is hidden by that of the second, which, as well as that belonging to the third pair of limbs, is largely developed. The coxa of the fourth pair of limbs is not so largely develcped as in Montagua, and moreover is excavated to receive the an- terior lobe of the coxa of the fifth pair of limbs, which is more developed than in Montagua, as is also the second joint of the same pair of legs. The posterior pair of caudal appendages are unibranched, and the telson is simply squamiform. This genus, of which we know only a single species, has received its name in honour of Professor Dana, whose work on the Crustacea has been of great assistance to us in our labour. 68 GAMMARIDA, AMPHIPODA. STEGOCEPHALIDES. NATATORIA, DANAIA DUBIA. Specific Character. Coxe of the second pair of gnathopoda, and of the first pair of pereiopoda, serrated upon the inferior margin. Second pair of gnathopoda haying the propodos broadest at the palm, which is convex and ciliated. Length, 33 of an inch. Montagua dubius, Spence Bats, Report Brit. Assoc. 1855, p. 57. Danaia dubia, Spence Barr, Ann. Nat. Hist. 1857, xix. 137. Cat. Amph. Brit. Mus. p. 59, plate x. fig. 1. Watts, Pop. Hist. Brit. Crust. p. 167. In general aspect this animal resembles a species of the preceding genus. The head is furnished with a straight rostrum, and the anterior lateral margin is pro- duced anteriorly to a point in a straight line, further in advance than the rostrum. The body of the animal is smooth; but the eighth, ninth, and tenth segments in- dicate a slight projection posteriorly on the dorsal sur- face. The eyes are probably like those in Montagua ; but they have not hitherto been satisfactorily examined. DANAIA DUBIA. 69 The superior antenne are more than half the length of the body of the animal. The first joint of the peduncle is longer than the head; the second joint is not much more than half the length of the first; the third is lost in connection with the flagellum, which is longer than the peduncle, and fringed with fine cilia; the inferior pair are not so long as the superior. The peduncle does not reach beyond the peduncle of the superior, and the flagellum is as long as the peduncle, and fringed with fine cilia. The first pair of limbs have the coxe hid by the cox of the succeeding pair; they are slender, and terminate in a long straight finger. The second pair of limbs have the first joint produced inferiorly and an- teriorly, so as to cover that of the first pair of limbs and the appendages of the mouth; the inferior margin is serrated upon the posterior half. The wrist is short and inferiorly produced ; the hand is broader at the palm than near the wrist; the palm is convex, slightly oblique, fringed with hairs, and imperfectly defined, the inferior angle being rounded. ‘The third pair of limbs have the first joint produced rather deeper than the preceding ; it is irregularly serrated the whole length of the inferior margin; the rest of the leg is long and slender, and furnished with many long hairs: the finger is long and powerful. ‘The fourth pair of limbs have the first joint deeper than the preceding, not serrated along the in- ferior margin, but furnished with a row of solitary equidistant short hairs planted within the margin; the posterior margin is excavated near the upper edge to receive the anterior lobe of the coxa of the succeeding pair of legs. ‘The rest of the organ is similar to that of the first pair. The fifth pair have the first joint bilobed and the second joint ovately dilated. The two posterior pairs resemble the fifth. The caudal appendages are 70 GAMMARIDS. styliform, the antepenultimate and ultimate pairs having their branches unequal and tipped with a few small spines. The terminal piece is pointed at the tip. The colour of the animal when fresh was pale straw, thickly blotched with rose-coloured patches over the body, and the coxe were colourless and very trans- parent. The animal was taken by us from some trawl-refuse brought from near the Eddystone Lighthouse, and is very elegant in its appearance, We are not able to give the precise size, since un- fortunately the only specimen which we have seen has not been preserved; but to the best of our recollection, the animal is about the eighth of an inch in length. We would also offer this as a reason for suggesting some reservation as to the exact correctness of the de- tails of the description; the figure was, however, taken from the animal when it was quite fresh, but it was lost before it could be examined more minutely. We have sometimes, indeed, thought it possible that the limb described and figured as one of the first pair of legs may be the extremity of one of the third pair of limbs accidentally thrown forwards, in which case the first pair of limbs may be subchelate, and if so, the animal must take its place as a species of Montagua, notwithstanding the reduced size of the fourth, and the enlarged dimensions of the succeeding coxe. With these causes for doubt on our mind, we deter- mined on the specific name. LYSIANASSIDES. 71 AMPHIPODA. LYSIANASSIDES. NATATORIA, Subfamily—LYSIANASSIDES. Superior antenne very short, with the base dilated and suddenly tapering. Coxe of the four anterior pairs of appendages very deep, the fourth not broader than the preceding. One pair of gnathopoda very slender, and imperfectly developed. In this subfamily the animals may readily be distin- guished by their general form. They are not much compressed, but the anterior cox are deep enough to hide the limbs attached to them. The superior antenne are always very short and pyriform, the shortness com- monly resulting from the second and third joints of the peduncle being almost rudimentary, while the flagellum is seldom longer than the peduncle. The first or second pair of limbs are generally short and strong, whilst the other is slender and feeble. In some genera it is the first, whilst in others it is the second, which is strong. We therefore propose to divide them into— a. Those genera which have the first pair of limbs robust, and the second pair feeble. b. Those that have the first pair of limbs slender, and the second strong. =~ rus) GAMMARID#, AMPHIPODA LYSIANASSIDES. NATATORIA, a. First pair of qnathopoda strong; second pair feeble and imperfectly cheliform. Genus—LYSIANASSA. Lysianassa, Epwarps, Ann. des Se. Nat. t. xx. Hist. des Crust. t. ili. p. 20. Dana, U. 8. Explor. Exped. p. 908. Generic character. Superior antenne very short, stouter than the inferior, appendiculate. First pair of gnathopoda not sub- cheliform. Second pair imperfectly developed, but long, mem- branous, and subchelate. Telson single, squamiform, entire. Tus genus may be distinguished by its short upper antenne being very stout near the head, and suddenly reduced in size at the base of the flagellum, which is very short, and carries a secondary appendage. The inferior antennee are more slender and often longer than the superior. The mandibles are furnished with a jointed appendage, and armed with a sharp, smooth, cutting edge, carrying a stout tubercle upon the anterior margin. The pair of foot-jaws have large squamous pro- cesses attached to the third and fourth joints. The first pair of limbs are not formed into a claw, but terminate in a straight finger, which imperfectly bends upon the hand. The second pair are feeble and very long: this latter circumstance is due to the great length of the third joint, which, in most of the animals of this Order, is very short. The coxe of the four anterior pairs of limbs are deeper than the segments of the body to LYSIANASSA, 10 which they are respectively attached; whilst the three posterior pairs of coxe are much shorter than the pre- ceding. The legs are all subequal in length. The caudal appendages are short, the posterior, as well as the two preceding pairs, terminating in two branches. The middle tail-piece is single, squamiform, and entire. The vignette below represents Salcombe Harbour, Montagu’s favourite hunting-ground, from a sketch by Mr. P. Mitchell, of Plymouth, 74 GAMMARID#. AMPHIPODA., LYSIANASSIDES. NATATORIA, LYSIANASSA COSTA. Specific character. Inferior antenne not longer than the superior, the flagellum of each being shorter than their respective peduncles. Length J of an inch. Lysianassa Costa, Epwarps, Ann. des Sc. Nat. t. xx. p. 365, pl. x. fig. 17. Hist. des Crust. t. iii. p. 21. Sprenox Bare, Report Brit. Assoc. 1855, p. 58. Ann. Nat. Hist. (1857) xix. 138. Cat. Amphipoda, Brit. Mus. p. 69. pl. x. fig. 11. Wurrr, Pop. Hist. Brit. Crust. p. 167. Gammarus glaber, (Spinola MS.) Wurre, Cat. Brit. Mus. (Crustacea), 1847. THE eyes are reniform, of a brown colour, and mode- rately large. The superior antenne are not longer than the head and the first two segments of the body, while the peduncle is scarcely longer than the head, and the flagellum scarcely as long as the peduncle, the former consisting of six or seven articuli, and the secondary LYSIANASSA COSTA. 75 appendage of only two. The inferior antenne do not reach beyond the extremity of the superior; they are much more slender, and have a considerable portion of the peduncle covered by the lateral walls of the head. The epistoma considerably projects, and is formed into a wedge-like process, rounded and projecting above, receding towards the inferior margin, where it corre- sponds with the lower extremity orcutting margin of the mandibles. The mandibles, d, are long and narrow, narrower a little towards the cutting margins than at the base, which articulates with the head; the molar tubercle is long, narrow, and slightly curved: the incisive margin is smooth, a- form which, as far as we are aware, is peculiar to this subfamily, and suggests the idea of its being adapted for cutting vegetable substances ; the blade is hollow, or cup-shaped, being separated from the remainder of the mandible by a sudden constriction or neck; the anterior margin, where it is increased in width, is produced into a small tubercle; the man- dibular appendage is three-jointed, which is a very common form in the Order. The pair of foot-jaws, g, have the fifth jot very long, being much longer than the sixth. The third and fourth joints are pro- duced into large squamiform plates, which nearly reach to the extremity of the fifth joint; the inner margin of the squamous plate of the fourth joint is slightly scalloped, and furnished with rudimentary spinules which respectively correspond with the scollops at the margin of the plate. These spinules, although of a very obsolete character, appear to differ very consi- derably in different species; and we think that they may be found of very considerable service in detecting the relative value of species, where it may be desirable 76 GAMMARID&. to ascertain that circumstance from specimens in which the more prominent features have been lost. The two anterior pairs of limbs bear an aflinity to those of the genus Talitrus. The first pair are strong and robust, having the finger sharp and straight, and incapable of being inflexed upon the hand, which is of considerable length, and gradually tapering to its extremity, where it is not broader than the base of the finger: the coxa of this pair of limbs is very thin and transparent, pro- jecting so far anteriorly that (when the head is bent downwards) it covers all but the last joint of the peduncle of the-inferior antennz, which is clearly seen through it. The second pair of limbs are much longer than the first; they are exceedingly thin and slender, and exhibit, in a marked degree, the peculiarity of the genus, in having the third joint remarkably long: the wrist also is very long, being much longer than the hand, which is very short, and furnished with a very short finger, so that the organ can but be of little value in grasping or securing any object of prey, a circum- stance which would again suggest to us the habits of a vegetable rather than a carnivorous feeder. The third and fourth pairs of limbs are similar in form, except that the coxa of the fourth pair has a deep emargination for the reception of the anterior lobe of the coxa of the fifth pair. The three posterior pairs are also formed upon a uniform plan, and scarcely differ in length; the posterior margins of the broad squamiform plates of the second joints are scalloped, a small hair springing from the depression formed by each scallop. The caudal appendages are short, and in general form approximate those of leaping rather than those of swimming amphi- poda. ‘The penultimate pair are shorter than either the preceding or the following; they all have their branches LYSIANASSA COSTA, viv shorter than their peduncles, and are naked, being un- furnished with either spines or hairs. The middle tail- scale is round at the apex, squamiform, superiorly con- cave, and furnished subapically on each margin with one solitary cilium. The structure of the skin, as viewed beneath the microscope, shows but a number of minute granules scattered thickly over the texture, while minute cilia are seen to spring upright from its surface. The animal is sometimes very transparent, verging to a gray along the dorsal surface, where each segment is marked with a white patch. The anterior portion of the body is tinted with yellowish brown, and one or more spots of the same colour exist upon each segment, and on some of the coxe. We have received specimens from Tenby, where it was dredged by our friend Mr. Webster, to whom we are indebted for Crustacea from many different localities. Mr. Alder has taken a single specimen on the coast of Northumberland. We have also taken it at Plymouth, and found it amongst Mr. Thompson’s Collection of Amphipoda, marked as having been taken at Belfast by Mr. Hyndman. The original specimen named by Prof. Milne-Edwards is still preserved in the Collection of the Jardin des Plantes at Paris, and through his courtesy aud kindness we have been able to examine and compare it with the British form. The type was taken at Naples. The specimen in the British Museum, presented by the Marquis Spinola, under the name of Gammarus glaber, unquestionably belongs to this species. Specimens also which answer to the description of this species have’ been taken at Sukkertopper, near Greenland, in forty fathoms by Mr. Holbdéll. The form appears to be re- peated in several parts of the world; for the species 78 GAMMARIDA. E. nasuta of Dana, taken on the coast of Brazil, and L. variegata, taken by Mr. Stimpson in Simon’s Bay, Cape of Good Hope, except, perhaps, in size, can with difficulty be distinguished from this species. L. Magel- lanica of Edwards, brought from the southern extremity of South America by M. D’Orbigny, also bears to it a close general affinity, but differs materially in size: the British species being probably the smallest of the genus, whilst the Magellan form is the largest, and pro- bably also the largest known normal Amphipod, being about three inches in length, forming a fit companion to Uristes gigas of Dana, and Cystosoma of Guerin. The accompanying vignette of Audleyn Castle, on the coast of Co. Down, Ireland, was kindly sketched for us by Mrs. Campbell, of Stoke, Plymouth. LYSIANASSA AUDOUINIANA, 79 AMPHIPODA. LYSIANASSIDES, NATATORIA, LYSIANASSA AUDOUINIANA. Specific character. Inferior antenne shorter than the superior, having the flagellum almost rudimentary. Length, ¥ of an inch. Lysianassa Audowiniana, Spence Barr, Rep. Brit. Assoc, 1855, p.58. Ann. Nat. Hist. (1857) xix. 188. Cat. Amph. Brit. Mus. p. 69, pl. xi. fig. 1. Waite, Pop. Hist. Brit. Crust. p. 168. Tue head is very short and very deep, having a large space between the superior and inferior antenne ; the ophthalmic lobe is not prominent, and the inferior margin is produced downwards. The eyes are large, oblong, slightly waved, broader below than above, white, marked with black spots, the latter, on close observation, being apparently caused by a series of hollows in the white surface, the black being seen through the perforations. The superior antenne are 80 GAMMARIDA. as long as the head and first segment of the body; the peduncle is longer than the flagellum, and the first joint longer than the other two, the third being shorter than the second. ‘The flagellum consists of four articuli, the first of which supports a brush of hairs, or rather one or two short rows of auditory cilia—long, delicate mem- branous organisms, somewhat like transparent hairs, and evidently intimately connected with the sensation of hearing; the secondary appendage is minute and slender, consisting of two articuli only, one much longer than the other. The first pair of legs are short, and have the coxa but little developed; the hand is tapering, and furnished with two hairs near the base of the finger; the finger is slightly curved, terminating in a short nail, and armed along the inferior margin with two minute spinules. The second pair of legs are long and slender, having the coxa deeper than that of the preceding pair ; the wrist is nearly as long again as the hand, and has the inferior margin thickly ciliated with long hairs; the hand is not broader than the wrist, and has the upper and lower margins nearly parallel, and thickly furnished with long hairs; the inferior angle is considerably produced, so as to give to the organ a chelate character, although, from its minute dimensions, one of feeble importance. The finger is straight and tapering, having the apex subapically furnished externally with a curved spine. The third and fourth pairs of legs are subequal, toler- ably robust, and alike, except in the form of their coxa, which is much larger in the fourth than in the third pair, and has a slight emargination, corresponding with the margin of the anterior lobe of the coxa of the fifth pair of legs. The three posterior pairs of legs are also of the same length and form, tolerably strong, though not so robust as the two preceding; their second joints are LYSIANASSA AUDOUINIANA. $l oblong-ovate, and have the posterior margin simple. The caudal appendages are simple: the antepenultimate pair have the branches styliform, naked, slightly curved, and tipped with a rudimentary spine; the penultimate resemble the preceding, except that the posterior margin of each branch has its distal moiety minutely serrated. The ultimate pair have the base very short, and one branch simple, the other two-jointed and tipped with a minute spine; the inner margin of the single-jointed branch, and the first joint of the double-jointed one, are minutely serrated. The central tail-piece is simple, squamiform, concave above, and rounded at the apex. The animal is of a dull yellow colour, darkest along the course of the alimentary canal. This species has been taken by us, in Plymouth Sound, with a dredge ; but we have not noticed it among those Crustacea sent to us by our many obliging correspond- ents from other localities. The species is named in honour of M. Audouin, the able coadjutor of M. Milne-Edwards, and who, as the describer of the Amphipoda in Savigny’s ‘ Egypt,” must be reckoned among the pioneers of this branch of Car- cinology. G 52 GAMMARIDA, AMPHIPODA, LYSIANASSIDES. NATATORIA. LYSIANASSA ATLANTICA. Specific character. Inferior antenne as long again as the superior. Length §; of an inch, Gammarus Atlanticus. Miunn-Epwarps, Ann. des Sc. Nat. t. xx. Lysianassa Atlantica. Miunu-Epwarps, Hist. des Crust. t. iii, p. 22. Spence Bare, Cat. Amph. Brit. Mus. p. 68, pl. x. fig. 10. Lysianassa marina. Spence Barr, Ann. Nat. Hist.v. xix. p. 188 (1857). Waitt, Pop. Hist. Brit. Crust. p. 168. Opis lypica, Wuitt, Pop. Hist. Brit. Crust. p. 168. Cat. Crust. Brit. Mus. 1850, p. 49 (but not of Kroyer, Nat. Tidsk. iv. 149, Voy. Scandin. tab. 17, fig. 1.) THe superior pair of antennz are not longer than the head and first two segments. They have the first joint of the peduncle very large; the upper margin is con- tinuous with the upper line of the head, and suddenly curved down towards the distal extremity—a circumstance LYSIANASSA ATLANTICA. 83 that, at the first glance, gives it the appearance of being the anterior extremity of the head ; the second and third joints overlap each other, and are reduced in length to the limits of very short joints, and not half as broad as the first. The flagellum is not so long as the peduncle: it consists of seven articuli, of which the first is longer than the two last joints of the peduncle together; the rest, together, are as long again as the first. The in- ferior antennz are as long again as the superior, and> much more slender. The peduncle does not reach be- yond the peduncle of the superior; the flagellum con- sists of about twenty-one or twenty-two articuli, of which the first is as long as the two following; each articulus carries one or two minute hairs; but the in- ferior, as well as the superior pair of antenne are very free from any appearance of cilia, The organs of the mouth are hid by the lateral appendages. The first pair of legs have the coxa deeper than the segment to which it is attached, the other joints are long and slender, the wrist is continuous with, and as long as, the hand: it increases in diameter until it meets the posterior ex- tremity of the hand, which is its broadest part; the hand is there also at its broadest diameter, from which it gradually tapers to the distal extremity, where it sup- ports a short, slightly-curved finger. The second pair of legs are a little longer than the first; the coxa is deeper than the second segment; the wrist is longer than the hand; the hand is but little broader than the wrist, upper margin arcuate, inferior straight, palm very short, truncate, fringed with short cilia, and defined from the inferior margin by a right angle. The distal half of the upper margin is fringed with several rows of long hairs. The perambulatory legs are subequal in length; the two anterior pairs (or the third and fourth pairs of legs) G2 84: GAMMARID. have the coxee deeper than the respective segments to which they are attached. The coxe of the fourth pair have an emargination that extends more than half its depth, for the reception of the anterior margin of the coxe of the fifth pair of legs. The remaining joints of the first two pairs are uniform. The three posterior pairs are also conjointly uniform ; their coxz are shorter than their respective segments of the body ; the second joints have the squamous plates broader above than below, and are postero-inferiorly produced, so as almost to reach to the distal extremity of the third joint; the fourth joint is “somewhat dilated, the wrists are short, the feet longer than the wrists, the fingers are short and pointed. The caudal appendages are subequal, the pos- terior pair being rather the shortest. The middle tail- piece is as long as the branches of the posterior pair of the caudal appendages. It is squamous and simple. We dredged the first specimen of this species in Plymouth Sound, and described it under the name of L. marina. We have also received it from one of our most valued correspondents, Mr. Edward, of Banff, who took it in the neighbourhood in which he resides; and Mr. W. Thompson has found it in Strangford Loch, Ireland. Since the publication of the ‘‘ Synopsis of the British Amphipoda,” we have had the opportunity of examining the type of M. Milne-Edwards’ species, L. Atlantica, preserved in the Museum of the Jardin des Plantes, and are thereby enabled to identify the British species with that taken in the Atlantic Ocean. This species, like L. Coste, appears to be represented, by close resemblance of form, by species existing in dis- tant localities, of which ZL. Kroyeri, from Van Dieman’s Land, is an example. LYSIANASSA LONGICORNIS. 85 AMPHIPODA. LYSIANASSIDES. NATATORIA. LYSIANASSA LONGICORNIS. Specific character. Inferior antenne longer than the animal in the male? but a little shorter in the female. Length $ in. Lysianassa longicornis. Lucas, Expl. Sci. Algerie Zool. i. Crust. p. 53, pl. 5, fig. 2. Spence Bary, Cat. Amph. Brit. Mus. p. 70, pl. xi. fig. 2. Ann. Nat. Hist. 2nd Ser, xx. p. 525 (Jan. 1858.) Lysianassa Chausica. Spence Bary, Ann. Nat. Hist. (1857) v. xix. p. 138. Wuirr, Pop. Hist. Brit. Crust. p. 168, (not Alibrotus Chausicus M.-Edwards’ Hist. Crust. iii; 23.) Tue head has the lobes between the antenne pro- duced to a somewhat down-curved point, extending fur- ther forwards than the upper extremity of the head, and extending beyond the basal half of the first joint of the peduncle of the upper antennae. The back is long and smooth; but the three last joints of the tail are suddenly 86 GAMMARIDA. lessened in diameter. The eyes are moderately large, somewhat reniform, and of a black colour. The upper antenne are equal in length to the head and first two segments of the body taken together ; the peduncle has the first joint as long as the upper margin of the head, the second and third joints are successively shorter; the flagellum, which consists of six or seven articuli, is shorter than the peduncle, but the secondary appendage is nearly as long, though much more slender, than the peduncle. The lower antennz have the peduncle as long as the upper organs; the first four joints are very short, but the fifth reaches to the extremity of the upper antenne; it is of a peculiar shape—narrow near the base, it suddenly enlarges, leaving a hollow upon the lower margin, that enables the antennz at this joint to be reflected back upon itself, and thus the organ is carried, close pressed beneath the body of the animal, which is its usual position; from the widest diameter, which is at the extremity of this hollow or notch, the joint gradually tapers to the apex. The flagellum is very slender and long, reaching much beyond the ex- tremity of the animal. Lach articulus of the flagellum is a little longer than broad, and carries upon the upper margin, which is slightly raised near the centre for that purpose, a small membranous vesicle, in form like an inverted shoe, from which resemblance Mr. Stimpson, the naturalist of the United States’ Expedition to Japan, has given it the name Calceola. 'The use of these organ- isms is not known; Mr. Stimpson has, however, informed us that they are peculiar to the males; whilst our expe- rience tells us that they are not common to the males of all Amphipoda, nor, in fact, to those of this genus ; neither do they appear to be so common to species which belong to the British seas as to exotic forms. LYSIANASSA LONGICORNIS. 87 Believing that the inferior antenne are organs adapted for the sense of smell, we may conjecture that these membranous attachments have the power of increasing that faculty to a more acute degree. The fact of their being found in the males only would seem to corrobo- rate this supposition, since undoubtedly the males seek the other sex by the use of this sense, as the following experiment appears to demonstrate. Having separated a male amphipod from a female, which he was carry- ing about with his legs, the latter immediately swam to a place of security, but the male dashed eagerly round the trough in which they were confined. While swimming about, however, we observed that, having passed by his mate, he would turn back, and select her from among several others. We think that this could only have been performed by the agency of smell, and therefore consider these calceola as organisms, connected with and increasing the capability of that sense in the male amphipods where they exist. The epistoma projects in a narrow perpendicular wedge- like process, with a rounded apex, over which the in- ferior antenne bend. The mandibles do not materially differ from those of species of this genus previously described. The foot- jaws have the fifth joint very long, nearly three times as long as the sixth, and have squamous plates attached to the third and fourth joints; the plate belonging to the fourth joint has the outer margin minutely waved, and furnished with a submarginal row of minute cilia, that of the third joint reaches to half the length of the fourth, and is furnished towards the distal extremity with a thick brush of cilia. The first pair of legs are short and tolerably robust ; the wrist is about half the length of the hand and stouter; the hand from its articulation with 88 GAMMARIDA., the wrist gradually tapers to the distal extremity, where it supports a short straight finger. The appendage is but scantily clothed with hairs. The second pair of legs are long and slender, having the wrist twice as long as the hand, with the inferior margin convex and the su- perior straight, the widest part being near the middle of the joint; the hand gradually but slightly increases in diameter to the extremity, where the inferior angle is produced in advance of the palm, and thus gives the part a nearer approximation to a chelate organ than is common in this order of Crustacea. The upper margin of the hand to the apex is thickly furnished with long double-branched hairs, the lower margin is studded with straight parallel hairs, and the inferior angle covered with short thick spines or obtuse hairs, very minute. The fin- ger articulates near the centre of the extremity of the hand, and is short, sharp-pointed, and curved. The walking legs are subequal, and do not materially differ from those of other species of this genus. The two pen- ultimate pairs of caudal appendages are styliform, and have the branches subequal in length, the upper margins being furnished with a few short hairs. The last pair reaches much further posteriorly than the two preceding, but the basal joint is very short, while the branches are long, subequal, and thickly furnished with long plumose cilia. The central tail-piece exhibits no peculiar character. The colour of the animal, when fresh taken, was bright orange, mottled with red spots along the sides of the body, just above the legs. The specimen from which our drawing is taken was dredged by us in Plymouth Sound, and described under the name of Lysianassa chausica, being under the impression that it agreed with Kdwards’ description of Albrotus chausicus; but through the kindness of the authorities at the British Museum, LYSIANASSA LONGICORNIS, 89 our attention was drawn to a species resembling this in Lucas’ Description of Crustacea taken on the shores of Algeria; since which time we have had the opportunity, through the kindness of M. Lucas (who permitted us to examine the Crustacea in his private collection), of identifying the present specimen with that taken by him on the northern coast of Africa. Among the Crustacea forwarded to us by that obliging aud indefatigable naturalist, Mr. Edward, of Banff, we have found a portion of an animal of this species from the Moray Frith. We are also indebted to Professor Kinahan, of Dublin, for several specimens from Dublin Bay. All the specimens from the last-named locality have the lower antenne shorter than that given in our description and figure of the species, and do not possess the calceola attached to the same appendage—circum- stances which have induced us to conclude that these were female specimens, 90 GAMMARIDA. AMPHIPODA. LYSIANASSIDES. NATATORIA. Genus—ANONYX, Kroyer. Anonyx Kroyer. Gréxuanp, Amfip. p. 15; Nat. Tidsk. v. ii. p. 256. Generic character.—Superior antenne short, pyriform, furnished with a secondary appendage. Mandibles having a smooth incisive margin and a palpiform appendage. First pair of gnathopoda subchelate ; second pair long, slender, feeble, and subchelate. ‘'Telson single, squamiform, cleft. = TuIs genus was separated from Lysianassa by Kroyer, from the subchelate form of the hands of the third pair of limbs (“ parvulo instructi ungue”), and from the fourth pair of limbs being destitute of a terminal hook, (whence the generic name,) the place of which is sup- plied by a brush of hairs. Also the middle tail-piece, instead of being entire, as in Lysianassa, is divided more or less deeply in Anonyx. Neither of these characters are capable of being distinguished without close exami- nation, and in some species, dnonyx lagena for example, the extremely oblique palm of the hand approximates, in its form, to that of a Lysianassa; again, the divi- sion of the central tail-piece is occasionally so slight, as in A. obesa, that a small depression alone exists. The genus Opis, of which Kroyer has described two species, differs from Anony# in the opposite extreme. As Lysianassa has a less perfectly chelate hand than Anonyx, so Opis possesses one that is still more perfect as a didactyle claw. This grouping, although convenient, appears to us to be arbitrary ; moreover, it is not improbable that some of the forms may be only sexual. ANONYX LONGICORNIS. 91 AMPHIPODA. LYSIANASSIDES, NATATORIA. ANONYX LONGICORNIS. Specific character. Central dorsal line slightly carinated. Third seg- ment of the pleon tuberculated at the posterior dorsal margin. Inferior antenne longer than the animal. ‘Telson very long and deeply cleft. Length $ in. Anonyx longicornis. Sprnce Barn, Cat. Amph. Brit. Mus. p. 72, pl. xi. fig. 4. THIS animal in its general form differs considerably from the type of the genus, which is round and smooth, while this puts on an angulated appearance. The head is produced a little in front, the back is slightly carinated through the entire length of the animal, the tenth seg- ment (N) of the body is posteriorly produced to a tuber- cle, and a deep sinus indents the anterior dorsal portion of the next, which is also posteriorly elevated into a long tubercular ridge. 92 GAMMARIDA. The eyes are small and oval; they appear smaller than they really are, for the black pigment is only visible in the centre of the organ, the several lenses forming an areola round the central spot. The superior antenne are short. The first joint of the peduncle is as long as the head, and has the upper margin produced anteriorly so far that it reaches to the extremity of the third joint. The second and third joints are short and small, and gradually taper to the extremity of the flagellum, which consists of but two or three articuli. We have not observed the secondary appendage. The inferior antennz are long, longer than the entire ani- mal, and very slender. They bear a considerable re- semblance to the same organ in Lysianassa longicornis. The third and fourth joints of the peduncle are short, being as broad as long; the fifth or last joint is very long, hollowed upon the under side near the base, swelled near the middle, and gradually tapering to the distal extremity ; the flagellum is very slender and long, and is formed of articuli which are long and slender, every articulus being furnished with a calceola—a fact, which, if Stimpson be correct, shows that our specimen is a male animal. The first pair of legs are long and slender, having the wrist longer than the hand, and the under margin parallel with the upper; the hand is not broader than the wrist, and also has the under margin parallel with the upper, the palm is short, oblique, and concave. The second pair of legs are long, slender, and membranaceous; the wrist is longer than the hand; the hand has the infero-anterior angle produced to a blunt point beyond the palm, equal to the length of the finger, which is very short, and therefore approximates nearly to a didactyle claw. The first two pairs of walking legs are slender. The last three have the ANONYX LONGICORNIS. 93 second or squamose joint posteriorly and inferiorly pro- duced, so as to cover the third joint and part of the fourth: the fourth joint is very peculiar, being pos- teriorly developed to a squamose plate, with the upper and lower margins posteriorly depressed, and almost parallel, as are also the anterior and posterior margins— circumstances that give to the joint the form of a diagonal parallelogram. The wrist is very long, longer than the hand, and stouter ; the hands have the margins parallel; fingers long, slender, and straight. The two posterior pairs of legs are subequal, and considerably longer than the preceding. The caudal appendages are subequal in length; the two anterior pairs are free from hairs or spines, and reach to the same dis- tance, the branches being equal. The posterior pair have the branches equal to each other in length, but a little longer than those of the two preceding pairs ; they have the inferior margin straight, or nearly so, tending rather to a hollow than to a convex outline, while the upper margin is arcuate, and furnished with a thick fringe of hairs, The terminal plate is very long, reaching to two-thirds the length of the posterior pair of caudal appendages. We received this interesting specimen from our valued friend and correspondent, Mr. Geo. Barlee. He obtained it, with many other Crustacea, from the Haaf fishing- grounds off the coast of Shetland. 94: GAMMARIDA, AMPHIPODA. LYSIANASSIDES. NATATORIA. ANONYX EDWARDSI. Specific character. Inferior antenne scarcely longer than the superior. First pair of gnathopoda short, robust, having the propodos broader near the carpal extremity than at the palm. Palm but slightly oblique, defined by an almost right angle. Length 3, of an inch. Anonyx Edwardsi. Kroyer, Voyage en Scand. pl. xvi. fig. 2, Branpt, Middendorff’s Siberische Reise, pl. xi. fig. 7. Lrtsn- BORG, in Ofvers. af Kongl. Vetensk. Akad. Forhandl. 1851, No. 38. Wurtz, Pop. Hist. Brit. Crust. p. 170, pl. x. fig. 8. Spence Bats, Ann. Nat. Hist. xix. p. 188 (1857) ; Cat. Amph. Brit. Mus. p. 73. pls xtadige D? Tuis animal bears a general resemblance to Lysianassa ' Coste. It has a sinus in the middle of the antepenulti- mate segment of the body. The eyes are subreniform, and of a white colour covered with black spots. The superior antenne have the peduncle as long as the head, ANONYX EDWARDSI. 95 the second and third joints suddenly narrowing, giving to the upper margin an arcuate line, while the lower is straight; the flagellum is about the same length as the peduncle, the first articulus being nearly half its entire length. The secondary appendage is nearly as long as the flagellum. The inferior antenne are about the same length as the superior; the joints forming the peduncle are short, except the last, being hidden behind the pro- jecting lateral lobes of the head. The epistoma is rounded in front, and projects as far in advance as the frontal wall of the head. The foot-jaws are short, and have the fifth and sixth joints subequal in length, but neither of them are much longer than the seventh. The plate which is attached to the fourth joint has the inner margin crenulated, where the rudiments of a spine cor- responds with each lobule; a single strong spine sub- apically crowns the plate. The first pair of legs are short and robust, they have the wrist and hand nearly of the same length, and continuous with each other, forming a long imperfect ellipse, the broadest part of which corresponds with the articulation between the two joints. The palm is the narrowest part of the hand; it is smooth, and defined by a right angle that projects a little beyond the regular line of the inferior margin: the finger is short, strong, and curved. The second pair of legs are long and slender, having the third joint nearly as long as the fourth, the fifth much longer than either, and as long again as the hand, it is inferiorly produced to a lobe, which is thickly covered with a fur of short stiff hairs, above which, on the inner side as well as on the upper mar- gin, is a double row of similar hairs which extend longitu- dinally along half the length of the joint. The hand is rounded at the apex, furnished with five rows of hairs 96 GAMMARIDA. running across the axis of the joint, and covered below and at the apex with a fur of short hairs, amongst which the small finger is lost to observation, except under very high magnifying power. It must therefore appear, if there be any prehensile capability in this and other similar appendages, that it is not obtained through any assistance that can be derived from the finger, but by the pressure of the hand back against the hairy cushion on the inferior surface of the wrist. The first two pairs of walking legs are small, and the last three appear to be more robust; they are rather curved, and have the second joint developed to a broad oval shape, which is produced infero-posteriorly, so far as to cover the next joint; their posterior margins are crenulated, and have a short hair springing from the depression between each lobule ; the fourth joint is broader in the fifth pair of legs than in the two following pairs; the sixth joint is slightly curved, the two margins being parallel. The three pairs of caudal appendages are short; the branches (which are of equal length on each) are very short, those on the posterior being a little the longest. The terminal scale is cleft through more than half its length. The tail generally has the appearance of being a powerfully thrusting organ, and it is undoubtedly used to propel the animal either backwards or forwards. The colour of the animal varies from a transparent pale yellow, in the young state, to that of a deep yellow or light brown tint. The eyes are red in the young, but become black in the adult animal. The structure of the skin appears not to exhibit any decided markings when examined by the microscope, but the surface generally is covered with minute solitary spinules or short hairs, dis- tantly scattered. This description, as well as our figure, is taken from a ANONYX EDWARDSI. 97 British specimen. On comparing it with Kroyer’s figure in his magnificent work cited above, the following differ- ences will be found. Kroyer represents the palm of the first hand as serrated, as also the inner margin of the finger. The serrature is, however, not deep, and we do not think that we should be justified in making a separate species upon characters so trivial, unsupported by other characters. We have also observed a slightly-serrated margin in some specimens. We have received specimens of this species from the Moray Frith, sent to us by the Rev. Geo. Gordon, and Mr. Edward, of Banff, who has forwarded to us the largest specimen that we have seen. From Falmouth it has been sent us by Mr. Webster; and we have dredged it in Plymouth Sound. H 98 GAMMARIDA. AMPHIPODA, LYSIANASSIDES. NATATORIA. . A) is ANONYX OBESUS. Specific character.—Three posterior segments of the pleon very short. Superior antenne having the secondary appendage as long as the primary, Inferior antenne scarcely longer than the superior. First pair of gnathopoda having the propodos ovate, tapering, palm continuous with the inferior mar- gin, and but slightly defined. Telson bilobed. Length 4 inch. Anonyx obesus. Spence Barr, Cat. Amph. Brit. Mus. p. 74, pl. xii. fig. 1. Tue animal is short, round, and obese, (whence its specific name has been derived,) and the tail extends but slightly beyond the last deep segment of the body. The eyes were not visible in the specimen which we have seen, which was sent to us preserved in spirits. The superior antennz are rather longer than the head. ‘The first joint of the peduncle is very large, the second and third short, the flagellum articulates with the peduncle upon a process of the third joint, and consists of six or seven articuli, the first of which is rather larger than the others. The secondary appendage is as long as the primary; it origimates in a depression immediately above the articulation of the flagellum, and consists of ANONYX OBESUS. 99 five or six articuli, each of which is respectively longer than the articuli of the flagellum, and the first is more than as long again as either of the others. The inferior antennz are scarcely longer than the superior. The first pair of legs are very robust; the wrist and hand together have the upper margins in form of a continuous curve; the inferior margin of the wrist is slightly pro- duced between the preceding joint and the hand, and is crowned with several long hairs; the hand is long, ovate; the upper margin more curved than the lower; the palm is continuous with the inferior margin, and defined by a small spine planted upon a tubercle near the carpal extremity, a second spine is placed one-third in advance of the preceding; the palm is fringed with a row of very minute cilia, and laterally defended by five or six equidistant hairs; the finger is strong, curved, and sharp. The second pair of legs are long, slender, and membranaceous; the third joint is longer than the fourth, and the wrist is much longer than the hand; both these last two joints increase in diameter towards their distal extremity, and are thickly covered with short straight hairs,—those upon the hand are more numerous, and altogether prevent the finger from being observed. The walking legs are short and very strong ; the last three pairs are more so than the preceding, and have the scale-like second joints almost disk-shaped; the fourth and fifth joints are also very broad, the former more so than the latter. The tail is very short. The lateral walls of the last three segments are very deep, especially those of the last joint; and when the caudal appendages are not extended they are almost covered by them, even when not rolled up. The caudal appendages are free from hairs or spines; their branches are styli- form, with a slight curve gradually tapering to a point. H 2 100 GAMMARIDA., The antepenultimate pair have the branches shorter than their peduncles; those of the penultimate and ultimate are longer; especially the latter, on the outer branch of which there is an articulation near the apex. The caudal plate is almost round, divided at the apex to more than half the depth of the plate, where the division is broader than at the apex, thus giving the plate the appearance of being bilobed. This species affords an example of the near approxi- mation of Anonyx and Lysianassa. The first pair of hands have the palm scarcely distinguishable from the line of the inferior margin, against which the curved finger impinges when closed. Having stated that this specimen was sent to us in spirits, we would here mention that we find, for a limited period (some months at least), specimens preserved in glycerine keep all the colour and transparency of living animals. This species was sent to us by Mr. Edward, of Banff, who took it in the Moray Frith, ANONYX DENTICULATUS. 101 AMPHIPODA. LYSIANASSIDES. NATATORIA. FSEEEEELE Fetzer SEEE ELE E EUR EREES' ANONYX DENTICULATUS. Specific character.—Third segment of the pleon produced on each side into a tooth, which is directed upwards and backwards, at a right angle with the inferior half of the posterior margin. Inferior antenne more than half the length of the animal. Length 3 inch, Anonyx denticulatus. Spruce Bars, Rep. Brit. Assoc. 1855, p. 58. Ann, Nat. Hist. 2 ser. vol. xix. 189 (Feb. 1857.) Cat. Amph. Brit. Mus. p. 74, pl. xii. fig. 2. Wurte, Pop. Hist. Brit. Crust. p. 171. THE animal is proportionably long, and in general form bears a considerable resemblance to Anonyw ampulla, from which it may be readily recognized by the posterior mar- gin of the last deep segment of the body being produced on each side backwards and upwards into a long flat tooth. The eyes in this species have not been observed by us, having only seen dead specimens. ‘The superior 102 GAMMARIDA. antenne are scarcely longer than the head; the first joint of the peduncle is long, nearly as broad at the distal ex- tremity as at the centre, and superiorly it considerably overlaps the second joint; the second joint is short, but not much narrower than the first, it also considerably overlaps the third; the third joint is very short, but longer on the internal upper margin than at the lower: the first articulus of the flagellum is as long as the peduncle, and is furnished upon the inner surface with two longi- tudinal series of rows of minute hairs; the rest of the articuli, about thirteen in number, are as broad as long, and inferiorly furnished upon the inner surface of each with three hairs. The secondary appendage is short, not being longer than the first articulus of the flagellum ; it consists of three articuli, the first long, the other two short. The inferior antenne are rather more than half the length of the animal; the last joint of the peduncle extends quite to the distal extremity of the first articulus of the flagellum of the superior antenne; the flagellum is long and slender, and reaches to half the length of the animal. The epistoma is not very prominent. The mandibles have both extremities of the incisive edge produced beyond the intermediate blade; the molar tubercle is furnished with a few short obtuse spines. The appendage is long, with the second joint longer than the third. The first pair of legs are long and slender; they have the wrist and hand subequal in length, the wrist being rather broader than the hand; it has the margins parallel, and terminates abruptly; the hand has the margins parallel, the palm is oblique, con- vex, being formed by the apical margin gradually round- ing into the inferior; it is minutely pectinated through its entire surface, and is defined only by the cessation of the small teeth ; the finger is long, slender, and slightly ANONYX DENTICULATUS. 103 curved, reaching to the extremity of the palm, and, when closed, impinging against it through its entire length. The second pair of legs are long, slender, and membranaceous ; the wrist is longer than the hand, and thickly furred with hair; the hand is almost oval, very hirsute, and terminating in a minute claw, which is almost lost in a brush of plumose hair at its extremity. The other legs are tolerably long and slender. The second joint of the last three pairs is oval, but not produced so as to cover any of the succeeding joints of the leg; the posterior margin is serrated, but more dis- tinctly in the last pair than in the other two. The caudal appendages are simple, the penultimate being rather shorter than the other two. The middle tail- piece is ovate, cleft down the centre nearly to the bot- tom, each division being furnished at its apex with a strong blunt spinule. Some of the hairs upon the first pair of legs terminate in a trident; others have the apex reflexed, so as to assume a club-shaped appear- ance. ‘The extremity of the finger also has a peculiar and probably unique feature,—the point, which is toler- ably fine, is protected by a little membranous sac, which appears to be formed so that the animal can cover or expose it at will. This species is as yet rather rare. We have received it from the Moray Frith, from our kind correspondents, the Rev. Geo. Gordon, and Mr. Edward. Professor Kinahan has sent us a single specimen from Dublin Bay; and recently it has been taken by Mr. J. Gwyn Jeffreys and the Rev. A. M. Norman, in Vedlom Voe, Shetlands. 104: GAMMARIDZ. AMPHIPODA, LYSIANASSIDES. NATATORIA. ANONYX HOLBOLII. Specific character.—Eye oblong. Superior antenne half as long as the inferior. Inferior antenne one-fifth the length of the animal. First pair of gnathopoda having the palm oblique, minutely pectinated, and defined by two small spines. Length 43 inch. Anonyx Holbolli. Kroyur, Voy. Scand. Crust. pl. xy. fig. la—s. Sprnce Bats, Rep. Brit. Assoc. 1855, p. 58. Ann. Nat. Hist. ser. 2, xix. p. 1388 (Feb. 1857.) Cat. Amph. Brit. Mus. p. 75, pl. xii. fig. 4. Warts, Pop. Hist. Brit. Crust. p. 170. Linsppore, in Ofvers. af Kongl. Vetensk. Akad. Forhandl. 1851, p. 22, No. 36. Tue general form of the animal is long and smoothly round over the back, the superior antennz appearing as a part of the head of the animal. The eyes are a long oval, assuming somewhat of the kidney shape. The colour of the organ is reddish, but in the specimens ANONYX HOLBOLLI. 105 which we have seen, the outline has been scarcely as defined as that given in our figure. In Kroyer’s beau- tiful plates in his ‘‘ Voyage en Scandinavie,”’ the form is given as wedge-shaped, slightly curved, the narrow extremity being uppermost, and the broadest down- wards, like an inverted comma (‘). The upper antenne have the first joint of the peduncle very long and stout, while the second is short and much narrower; the third being scarcely visible, a portion only of it extending beyond the limits of the preceding; the first articulus of the flagellum is very long, as long as all the others united, and is furnished upon the inner side with two longitudinal series of transverse rows of short hairs. It also supports at its extremity, upon the upper side, a bundle of auditory cilia; the rest of the flagellum consists of but six or seven articuli: the secondary appendage is long and slender; it is nearly as long as the flagellum, and consists of about eight articuli, of which the first is the longest. The lower antenne are about one-fifth the length of the animal, and as long again as those of the upper pair; the peduncle is shorter than that of the upper antennz, and less stout; the flagellum is long and slen- der, and has the articuli, of which it is composed, longer than broad. The mandibles are furnished with a plain cutting incisive edge, from near the base of which a row of minute curved hairs is continued, until they communi- cate, at the opposite extremity, with the molar tubercle. Each of these organs supports a very long three-jointed appendage, the second and third joints of which are fur- nished with hairs, increasing in length towards the distal extremity of each joint. The foot-jaws have the scale-like plate belonging to 106 GAMMARIDA, the fourth joint largely developed, having a row of tubercles or rudimentary spines on the interior margin, but which become developed into long, strong, and simple spines at the apex of the plate. The first pair of legs have subcheliform hands; but in this species these organs are not very robust. The hand is not large, but long and narrow, being scarcely wider at the palm than at the extremity near the animal. The palm is oblique, slightly convex, and furnished with a row of parallel equidistant teeth, offering a comb-like arrangement upon the margin of the organ, and is de- fined by two double-pointed spines, situated at the in- ferior angle, against which the finger, which is furnished with a second tooth or point, impinges. The second pair of legs are very long and slender; so slender as to be useless as prehensile organs, suggesting the idea of being adapted to the same purpose as the analogous imperfectly developed last pairs of legs in the section Anomoura, which are used for the purpose of cleaning and brushing the animal: they are plentifully covered with hairs, those upon the anterior margin of the hand being very long, while others upon the posterior margin are shorter and fewer in number. ‘The palm is but slightly oblique, and has the margin slightly waved ; the finger is small, and tuberculated near the base, it has the apex slightly curved, which, when it closes, antago- nizes with a strong spine; several of these spines lie concealed amidst the brush of simple hairs on the posterior margin. All these spines, when closely exa- mined, are found to have the side near the hand minutely serrated. The two anterior pairs of walking feet are slender: the three posterior are tolerably robust, and have the posterior margins of the second joints serrated, the last being the most perfectly so. Each of the caudal ANONYX HOLBOLLI. 107 appendages has its branches subequal; the penultimate pair are shorter than the preceding, or ultimate pairs. The terminal central piece is deeply divided, and each division has its apex truncated, and furnished with a central spine. The colour of the animal is transparently white, hav- ing spots of rose-colour near the dorsal surface, on each each side of the body, which in some specimens are less distinguishable in outline, their place being only indi- cated by a blush of the same colour. The original specimen was taken at Sukker-topper, by M. Holboll, in compliment to whom Kroyer proposed the specific name adopted above. We have received specimens from our valued correspondent, the Rey. Geo. Gordon, of Elgin; also from our indefatigable friend, Mr. Edward, of Banff; and Mr. Barlee has dredged it on the Haaf, about thirty miles off the Shetlands. It has been taken by the Rev. A. M. Norman and Mr. J. Gwyn Jeffreys in the outer Skerries Harbour, Shetland. Mr. Loughrin has sent us a half-grown specimen from Polperro, on the coast of Cornwall, and we have dredged it in Plymouth Sound. 108 GAMMARIDA., AMPHIPODA. LYSIANASSIDES. NATATORIA. ww ZZ em a, ° ANONYX MINUTUS. Specifie character.—Inferior antenne about one-third the length of the animal. Flagellum with the articuli broader than long, and possessing a moniliform appearance. The bases of the three posterior pairs of pereiopoda extending to the distal extremity of the meros. Length § inch. Anonyx minutus. Kroyer, Voy. en Scand. pl. xviii. fig. 2. Liusmzore, in Ofvers. Kongl. Vetensk. Akad. Forhandl. 1851, p. 22, No. 89. Wurrte, Pop. Hist. Brit. Crust. p. 170. Spancu Bare, Rep. Brit. Assoc. 1855, p. 58. Ann. Nat. Hist. ser. 2. xix, p. 138 (Feb. 1857.) Cat. Amph. Brit. Mus. ry YAS folly satya) (o} THE eyes in this species are small and round. The superior antenneze are very short, and have the first joint of the peduncle as long as the dorsal margin of the head, the second short, and the third almost obsolete. The first articulus of the flagellum is as long as the remaining seven or eight short ones, and is furnished on the inner surface with two longitudinal series of trans- verse rows of hairs. The secondary appendage is scarcely ANONYX MINUTUS. 109 longer than the first articulus of the flagellum, and consists of five or six articuli, of which the first is longer than all the others. The inferior antenne are three times as long as the superior, and about one- third the length of the animal; they have the last two joints of the peduncle short and subequal in length; the flagellum consists of many short articuli, each being rather broader than long, and united to the next by a compressed articulation, a circumstance that gives to the appendage in this species a moniliform appearance. The first pair of legs are short and toler- ably robust; the lower margin of the hand is nearly parallel with the upper, being rather broader at the base than at the distal extremity; the palm is straight, and defined by an almost right angle with the inferior mar- gin; the finger that completes the organ is short and strong. The second pair of legs are much longer than the first, as is, indeed, the case throughout the genus. The limb is very slender and membranaceous, and is mostly carried folded and compressed beneath the body of the animal; the wrist is much longer than the hand, and is inferiorly lobed, the lobes being covered with a number of small blunt triple-pointed spines, or rather plates ; towards the anterior margin these plates gradu- ally lose their complex character, and become simple spines; the hand is covered with a thick brush of short hair; those on the upper margin are planted in siX or seven transverse rows; towards the extremity they become longer; the finger is short, and scarcely visible amidst the hairs among which it is planted. The first two pairs of walking legs are tolerably robust. The last three are equally so, each having the second joint (which is universally developed into a squamose form in this genus) produced downwards, so far that, in the last two 110 GAMMARIDA. particularly, they cover the next and much of the suc- ceeding joint of the leg. The caudal appendages are short, those of the last pair having the peduncle and branches of nearly the same length. We have received specimens. of this species from Strangford Loch, where it was dredged by that inde- fatigable naturalist, Mr. Barlee; Mr. Webster has sent it to us from Falmouth. We have also dredged it in Plymouth Sound. The accompanying vignette is from a picture in the possession of Mrs. Hames, of Chagford. ANONYX PLAUTUS. 111 AMPHIPODA. LYSIANASSIDES., NATATORIA. ANONYX PLAUTUS. Specific character.—Inferior antenne scarcely longer than the superior. First pair of gnathopoda having the propodos tapering. Palm longitudinal, occupying the whole of the inferior margin. Length 54 inch. Anonyx plautus. Kroyer, Voy. Scand. pl. 15, fig. 2a-v. Spencer Bars, Cat. Amph. Brit. Mus. p. 78, pl. xiii. fig. 1. THE eyes of this species, in Kroyer’s figure, are sub- reniform ; in our specimen, however, we have not ob- served these organs. The superior antenne are but little longer than the head; the first joint of the peduncle is as long as the head, and the second and third joints subequally short and narrow; the flagellum is scarcely as long as the peduncle; the secondary appendage is very short. The inferior antennze are very slender, and but very little longer than the superior. The first pair of legs are 112 GAMMARIDA. short and very robust; the fourth joint has the inferior margin considerably produced anteriorly upon the wrist ; the wrist is short, very short upon the inferior margin, and arched upon the upper, forming an imperfect tri- angle; the hand is not so broad as the wrist, and gradually tapers to the distal extremity; the palm cor- responds with the inferior margin, and is imperfectly defined; a short spine marks the limit to which the finger can reach, which corresponds nearly with the en- tire length of the inferior margin. The second pair of legs are long, slender, and membranaceous; the third joint is as long as the fourth; the wrist is as long again as the hand; the hand increases in width towards the distal extremity; the palm is furred with minute hairs; and the finger is very minute. The first two pairs of walking legs are tolerably slender, whilst the last three are very short and robust; the second or squamiform joint is of an oval shape, and is inferiorly produced as far as the distal extremity of the third joint, and the posterior margin is slightly crenulated. In Kroyer’s figure this is not so represented, the margin being drawn smooth. The three posterior pairs of caudal appendages are short; the peduncles are stout, and increase in dia- meter posteriorly upon the upper margin; the branches are short, and free from hairs. The central terminal plate is round, only showing a slight depression at the apex. The specimen from which we drew our figure and de- scription was sent to us by Mr. Edward, of Banff, who procured it in that neighbourhood. ANONYX LONGIPES, 113 AMPHIPODA, LYSTIANASSIDES. NATATORIA. ANONYX LONGIPES. Specific character. Inferior antenne rather longer than the superior. First pair of gnathopoda having the carpus and propodos subequal, the margins parallel, palm short, slightly oblique, defined by one or two large spines near the inferior angle. Pereiopoda long and slender. Length about 4 inch. Anonyx longipes. Spence Bate, Cat. Amph. Brit. Mus. p. 79, pl. xiii. fig. 4. TuE animal generally bears some resemblance to A. Holbolli, from which it differs chiefly in the form of the first pair of hands. The eyes in this species are very small. The superior antennz are about twice the length of the head; the first joint of the peduncle is nearly as long as the head ; the next two joints are very short. The flagellum is I 114. GAMMARIDA, about the length of the peduncle; the secondary ap- pendage is short. The inferior antennz are very slight, and nearly half as long again as the superior. The epistoma is produced to a point. The first pair of legs are long and slender; the wrist and the hand are nearly of the same length, the wrist being slightly the longer of the two; they have the inferior margin pa- rallel with the superior; the wrist is rather broader than the hand, and has the inferior margin furnished with a slight brush throughout its entire length; the hand has the inferior margin slightly waved; the palm is oblique, and defined by a slightly obtuse angle, near which stands one or two strong spines; the palm is also armed with three or four short spinules. The finger is rather longer than the palm, but slightly curved, increasing in diameter near the centre, where it gradually tapers to a point, and is furnished with three small stiff spinules, which must add considerably to the prehensile capability of the organ. The second pair of legs are also very long, slender, and membran- aceous; the third joint is as long as the fourth; the wrist is half as long again as the hand, and furnished upon the under-side, which is not at all prominent, with a delicate fur of hair nearly throughout its entire length ; the hand is long, pear-shaped, the broadest axis being about one-third of its length from the apex; the in- ferior angle being produced; the finger, which is very minute, articulates posteriorly to the inferior angle, and therefore the hand approaches somewhat to the form of a double-fingered claw; the distal extremity of the hand is covered with a fur of fine hairs. The walking- legs are subequally long and slender, the three posterior having the second joint developed to a broad scale, the two last being produced a little downwards; except the ANONYX LONGIPES. 115 third, all the joints are long. ‘The wrists and the feet are subequal. The feet are furnished, upon the flexible side, with a few fine hairs, and a stout, sharp, short spine, curved reversely to the finger, which is long, slender, and appears capable of impinging against the front of the foot. The caudal appendages are subequal, the penultimate being slightly the shortest, and the branches of the last are unequal. The middle tail- piece is longer than the peduncle of the last pair of caudal appendages, This species was sent to us by our valued corres- pondent, Mr. Barlee, who dredged it on the Haaf Fish- ing-ground, about thirty miles off the Shetland Islands, where it has also been taken by the Rev. A. M. Norman and Mr. Jeffreys. Without examination it may be mis- taken for Lystanassa marina, (from which it chiefly differs in the generic distinction,) as well as for Anonyax lagena of Kroyer; but the peculiar form of the eye in the latter, which is tolerably large, and formed like an inverted comma, will offer a ready means of distinction, besides other, perhaps more important but less striking charac- ters. From A. ampulla it is distinguishable by the length of the inferior antenne. Our figure of this species is taken from a female spe- cimen. 116 GAMMARIDA, AMPHIPODA. LYSIANASSIDES. NATATORIA. ANONYX AMPULLA. Specific description. Inferior antennw very slender, and more than half the length of the animal. Length, 43 inch. Anonyx ampulla, Kroyer, Voy. Scand. pl. xiii. fig. 2. Spence Bare, Ann. Nat. Hist. ser. 2, xix. p. 139 (Feb. 1857.) Cat. Amph. Brit. Mus. p. 79, pl. xiii. fig. 5. Wuuare, Pop. Hist. Brit. Crust. p. 170. THE eyes in the only specimens of this species which we have seen are obliterated in consequence of being dried. The superior antennz are also damaged, so that the exact length cannot be stated; but the peduncle is very short, being scarcely half the length of the head; the first joint is scarcely longer than broad, the second is shorter, and the third almost lost to view; the first articulus of the flagellum is quite as long as the ped- uncle, the remainder are short; we have not, however, been able to determine their number, but in Kroyer’s figure the flagellum is represented nearly as long as the ANONYX AMPULLA. bia animal; the secondary appendage is about the length of the first articulus of the flagellum, and consists of one long and two very minute articuli. The inferior antenne are very slender and delicate; they are more than half the length of the animal, and generally lie concealed beneath the body; the peduncle reaches rather further than the peduncle of the superior, only two of the joints are visible beyond the margin of the head, of which the penultimate joint is very broad, and continues so to its extremity, whereas the ultimate is considerably narrower, but still very much broader than the articuli of the fla- vellum; the first articulus of the flagellum is longer than either of the others, but very small in diameter, while all the others are still more so—a circumstance that renders the entire flagellum exceedingly fine. The epistoma is produced to a sharp spear-like point, directed straight forward. The mandibles have the second joint of their appendage much longer than the terminal. The cox belonging to the first and second pairs of legs have the in- ferior margin smooth, except towards the posterior angle, which is elevated to a small tooth, immediately before which is a depression, from the bottom of which springs a short stiff solitary spinule. ‘The first pair of legs have the hands long and narrow, the upper and lower margins being parallel; the palm is slightly oblique and straight, but obsoletely crenulated, and defined by an obtuse angle, a little anterior to which stands a short stout spine, which is opposed to the tip of the closed finger; the finger is as long as the palm, and slightly curved. The second pair of legs are very long and slender; the third joint is longer than the fourth,—it is the great length of this Joint that gives the peculiarly slender and feeble appear- ance to this leg throughout the genus; the wrist is rather longer than the hand, and has the inferior margin 118 GAMMARIDA. and distal extremity furnished with hairs—those upon the latter position are very long, and split at the extremity into two branches; the hand is long and narrow, having the margins parallel and the apex truncate; the anterior half is furred with short hairs, a few long and large ones are also attached to the upper margin and apex; the finger is attached near the centre, so that the palm consists of but half the apical margin; its outline is waved, and the short finger is tuberculated upon the inner margin. The first two pairs of walking legs are uniform and _ tolerably robust ; the last three are equally so, but they have the second joint developed into an oval scale, which extends downwards as far as the extremity of the joint next suc- ceeding. The caudal appendages have their branches subequal, the penultimate pair are shorter than the pre- ceding or ultimate. ‘The terminal branches are furnished with short spines upon the upper and inner margins, those of the penultimate have the extremity of the inner branch subapically. furnished with a long spine, which gives this branch the appearance of terminating in a double extremity. The central tail-piece is divided to about two-thirds of its length; the outer and upper margin of each division is supplied with three equi- distant spinules, two or three more of which cover the apex of each half. These spinules or small hairs are subapically furnished with a branch still more minute. We have received specimens of this species from the Moray Frith, collected by the Rev. Mr. Gordon, of Elgin, and Mr. Edward, of Banff. From them our fizure and description are taken. On a comparison with the figure given by Kroyer, our specimens appear to be comparatively Ionger, but in all other respects their identity appears to be complete. CALLISOMA, 119 AMPHIPODA. LYSIANASSIDES. NATATORIA. b. Second pair of gnathopoda robust and more or less cheliform, Jirst pair feeble. Genus—CALLISOMA, Costa. Callisoma, Costa, Cat. dei Crost. del Regno di Napoli, 1840. Spunce Bare, Cat. Amph. Crust. Brit. Mus. p. 84. Scopelocheirus. Spunce Barts, Brit. Assoc. Rep. 1855, p. 58. Synop. &c. Ann. Nat. Hist. xix. 138, 1857. Wurtz, Hist. Brit. Crust. p. 168. Generic character. Resembles Anonya and Lysianassa, ex- cept that the first pair of gnathopoda are slender, and have the dactylos not unguiculate. Second pair robust, chelate. Pos- terior pair of caudal appendages unibranched. ‘'Telson bifid. THE superior antenne are short and thick at the base. The inferior antennz much more slender. The coxe of four anterior pairs of appendages are as deep as the seg- ments of the body to which they are respectively at- tached. The fourth segment has the posterior margin deeply excavated, to receive the anterior lobe of the fifth. The first pair of arms are long and slender, and have the finger terminating in a brush of hair. The second pair of arms are more robust than the first, and terminate in a very perfectly-formed didactyle claw. The walking legs correspond with those of the other genera in this subfamily; but the caudal appendages differ in having the posterior pair unibranched, and the terminal plate is bifid. 120 GAMMARIDA. AMPHIPODA. LYSIANASSIDES. NATATORIA. JALLISOMA CRENATA. Specific character. Inferior antenne one-third the length of the animal. First pair of gnathopoda having the dactylos developed into a thick brush of short hair. Fourth segment of the pleon having on the dorsal surface a deep notch. Length, $; inch. Callisoma crenata. Spence Barn, Cat. Amph. Brit. Mus. p. 85, pl. xiv. fig. 5. Scopelocheirus crenatus. Sprncu Barz, Brit. Assoc. Rep. 1855, p. 58. Synop. &c., Ann. Nat. Hist. xix. 138 (1857). Wuitr, Hist. Brit. Crust. p. 167. THIs species is very round and smooth, and rolls itself up almost into a ball. The head is small, and anteriorly produced into a minute flat rostrum, which is merely a projecting portion of the skin, extending horizontally with the top of the head. The antero-inferior angle projects as far forwards as the extremity of the rostrum. The eyes are small and reniform, showing black spots on a CALLISOMA CRENATA. 1 white ground. The superior antenne are very stout at the base; the first joint of the peduncle is nearly as long as the head, and almost as thick as long; the second joint is very short, and a little narrower than the first ; the third is very short, and almost covered by the pre- ceding; the flagellum has the first articulus very long, and broader at the base than at the distal extremity, the remaining articuli (six or seven in number) are small. The inferior antennez are slender, and about one-third the length of the animal; the peduncle is rather longer than the peduncle of the superior; the flagellum is very slender, and lies folded beneath the body of the animal. The first pair of arms are long and slender, and have the hand long and narrow, the margins parallel, the _ distal extremity being anteriorly armed with several fasciculi of strongly curved hairs; the finger consists of a thick brush of short stiff hairs. The second pair are more robust than the first; the hand is ovate, with the inferior angle produced and depressed; it ter- minates in a small tooth; the finger is rather longer than the process of the hand, and has the inner margin waved; together they form a very perfect claw, which bears a strong resemblance to those existing in some species of Soldier Crabs (Pagurus Dillwynii.) The third and fourth pairs of legs are not very robust; the three last gradually increase in length. The first squamose plate of the fifth pair of legs is almost round, and cor- responds anteriorly with a deep excavation in the pre- ceding; the second squamose joint is produced pos- teriorly, and is broader than long; the next joint is very short; but the fourth is produced posteriorly into a small squamose plate, fringed with hairs; the wrist is short, and stouter than the hand, which is long, slender, and has the margins parallel. The two posterior pairs 122 GAMMARIDA., are longer than the preceding, and more slender, and have the third joints and the wrists not broader than the next succeeding joints. The segment of the body which carries the ante- penultimate pair of caudal appendages is remarkable for a notch, deeply cut, near the middle, into its dorsal surface. The appendages are shorter than the penulti- mate; the penultimate is shorter than the ultimate; and both have their branches equal. The last pair have but one branch, which is much longer than the peduncle, and tipped with a strong single spine. The terminal plate is double, as in the genus Gammarus, each division being subapically tipped with a single spinule. The colour of the animal, when taken alive, is of a tolerably bright lemon, every segment and joint being fringed with a margin of white; the whole animal is thickly covered with minute black spots. The speci- mens which have been sent to us, being dead, were generally fawn-coloured, tending to a bluish-grey upon the back. This constant appearance, together with the animal being less compressed than Anonyx and Lysia- nassa, enabled us readily to recognize any specimen. The first species of this genus was indicated by the elder Costa in his ‘* Catalogue of Nepalese Crustacea,” published in 1840, and was subsequently described and figured in the ** Fauna del Regno di Napoli, Crust.,” pl. 8, fig, 4-7, by his son. ‘The lower antennz are not longer than the upper. A second species, C. Hopei, also from the Bay of Naples, was described and figured by the latter author in the “Catalogo dei Crostacei Italiani,” published by the Rev. F. W. Hope, Naples, 1851; and in the “Fauna del Regno di Napoli,” pl. vil. fig. 1. The lower antennz in this species are more than half the entire length of the animal. CALLISOMA CRENATA. 123 It is only recently that a third species has been taken, amongst some trawl-refuse brought in by the fishing- boats from near the Eddystone Lighthouse. We have also received it from the Moray Frith, where it appears to occur in considerable numbers. It has also been sent to us by Mr. Edward, from the neighbourhood of Banff; and from Macduff, where it was taken in a haddock’s stomach, from thirty or forty fathoms, by Mr. Gregor. It has also been taken by the Rev. A. M. Norman and Mr. J. Gwyn Jeffreys, in forty fathoms, on the Middle Haaf Fishing Ground, in great abundance. The vignette represents the entrance from the Moray into Cromarty Frith, and is from a sketch by the Rey. G. Gordon. 124 GAMMARIDA, AMPHIPODA. AMPELISCIDES, NATATORIA, Subfamily—AMPELISCIDES. Ampeliscades. Spmnce Bat. Cat. Amph. Crust. Brit. Mus. p. 90. Tetromatides. Spence Batu and J. O. WEestwoop, Rep. Brit. Assoc. 1855, p. 21. Organs of vision differing from the normal compound eyes of the Amphi- poda, and consisting only of single or detached lenses. Hands subchelate. WHILsT accepting the Genus AmMPELISca as the type, we are obliged to modify the characters of the present subfamily from those given in the ‘ Catalogue of Amphi- poda” in the British Museum, as undoubtedly the genus Hartoors of Liljeborg, with which we have only re- cently become acquainted, must be comprehended in it. The last-named genus, of which Professor Liljeborg has taken two species upon the coast of Norway, and which we may anticipate finding upon the northern shores of Britain, differs from AmPpertisca in the absence of the prolonged head, and in only having two instead of four simple eyes. We would here express our obligations to Professor Liljeborg, for his courtesy in sending us a drawing of Haploops tubicola. AMPELISCA, 125 AMPHIPODA. AMPELISCIDES, NATATORIA. Genus—AMPELISCA. Kroyer. Ampelisca. Kroyer, Nat. Tidskr. 1 ser. iv. p. 154, 1842. Spence Bate, Ann. Nat. Hist. ser. 2, vol. xx. p. 255. Cat. Amph. Brit. Mus. p. 90. Litspsore, Ofvers. af Kongl. Vetensk. Akad. 1851, p. 22 ; 1855, p. 137. Avraneops. Costa, Rend. del Accad. del Se. di Nap. 1853, p. 169. Pseudophthalmus. Stimpson, Marine Invert. Grand Manan. Proc. Nat. H. Soe. Boston. Tetromatus. Spence Baru, Brit. Assoc. Rep. 1855, p. 58. Ann. Nat. Hist. ser. 2, xix. p. 139. Wart, Hist. Brit. Crust. pe Led, Generic characters. Cephalon produced, and tapering an- teriorly. Hyes four, simple, two situated on each side, near the extremity of the cephalon. Superior antenne at the ex- tremity of the cephalon, without secondary appendage. Inferior antennse placed very far posteriorly to the superior. Mandibles having an appendage. Gnathopoda imperfectly subchelate. Pos- terior pair of pleopoda biramous. Telson squamiform, cleft. THE animals of this very curious genus have the body long, smooth, and more compressed anteriorly than pos- terlorly, so much so that the anterior portion of the dorsal surface presents a wedge-shaped appearance, but scarcely carinated. The head gradually tapers in front to an obtuse point, at the extremity of which the su- perior antenne are situated. The eyes are placed near the extremity of the head, and consist of two small simple organs upon each side, four in all, whence the generic name “ Tetromatus,” we had proposed, at the suggestion of our excellent friend, Mr. Adam White. The superior antenne are without a secondary append- 126 GAMMARIDA. age. The inferior antenne are situated very far pos- teriorly to the superior. ‘The mandibles possess a three- jomted appendage. The arms are slender, feeble, and imperfectly subchelate. The third and fourth pairs of legs are uniform, and have the fourth joints long and broad, the wrists short, and the fingers very long and styliform. The fifth and sixth are also uniform; they have the fingers short, and directed posteriorly. The seventh differ from the others, and have the foot broad and the finger straight. The posterior pair of caudal appendages are subfoliaceous; the branches are sub- equal. The caudal plate is squamiform, and cleft down the centre. The following vignette, for which we are indebted to our friend Dr. Scott, of Selby, Shetland, is a view of the Doreholms, Shetland, as seen by the Aurora Borealis. AMPELISCA GAIMARDII. hay AMPHIPODA. AMPELISCIDES. NATATORIA, AMPELISCA GAIMARDII. Specific character. Posterior margin of the third segment of the pleon plain. Superior antennew one-third the length of the animal. Inferior an- tenn very slender, two-thirds the length of the animal. Length, } inch. Ampelisca Gaimardii. Kroyur, Voyage en Scand. Crust. pl. xxiii. fig. 1. Spence Bats, Cat. Amph. Brit. Mus. p. 91, pl. Fay wien, IE Araneops diadem«a. A. Costa, Rend. del Accad. Se. di Nap. 1853, p. lial Mave teties alt Tetromatus typicus. Spence Barr, Brit. Assoc. Rep. 1855, p. 58. Synop. Ann. Nat. Hist. ser. 2, xix. p. 139. Ware, Hist. Brit. Crust. p. 171, pl. x. fig. 4. Tue anterior half of the animal is much more com- pressed than the posterior, and narrowed to an angle upon the dorsal surface, the angle increasing anteriorly to the extremity of the head. The eyes consist of simple 128 GAMMARIDA. lenses, four in number, two upon each side of the head, fixed in the integument itself. Behind these fixed eyes is a mass of dark-red pigment: close observation, with a microscope, exhibits this as connected with the organs of sight, threads of white pigment ramifying over the red mass, and appearing to consist of two sets, one be- longing to each organ, although only partially connected ; sufficiently so, however, to show that the two lenses belong to one and the same organ of vision. The number of lenses belorging to the eye of an Am- phipod increases with the growth of the animal; to such an extent is this the case, that whereas in the larva of a Gammarus, we have counted but eight, we find that in the adult there are no less than forty in each eye. We therefore consider that, in this genus, an arrest has taken place at an early stage, and limited the number of lenses to two, and thus produced an apparently imperfect organ of vision. The superior antenne are longer than the peduncle of the inferior, and are about one-third the length of the animal; the first joint of the peduncle is short and stout, and carries several fasciculi of hairs upon the inferior margin; the second is twice as long, and not so broad, and furnished upon the inferior margin with many fasciculi of hairs; the third joint is very short, and in- creases in diameter towards the distal extremity; the flagellum is about twice the length of the peduncle; the first articulus is as broad at the base as the last joint of the peduncle, and nearly as long; it gradually tapers to the distal extremity, the under margin is thickly crowded with auditory cilia of peculiar form; these are long and slender, the basal half broader than the distal, and the extremity furnished with a minute denticle; the rest of the articuli are small and slender, each carrying, above AMPELISCA GAIMARDII, 129 and below, two or three very minute hairs; the second articulus likewise carries a single auditory cilium. The inferior antenne are as long again as the superior, and reach to about two-thirds of the length of the animal. The third and fourth joints of the peduncle are furnished on the upper margin with fasciculi of hairs, the former through the entire length, the latter for a portion only; the last joint of the peduncle is longer and more slen- der than the preceding one: the flagellum, of which the first articulus is longer than either of the others, is very long and very slender, and is furnished with a few very minute cilia. The mandibles have the incisive margin armed with four or five strong teeth; within is a second plate, articulated with the mandible, and equally strongly armed; deeper within exists a broad strongly toothed molar process, between which and the moveable plate already referred to stands a row of stiff forked spines, each of which is denticulated along the margins throughout its length: the appendage of the mandibles has the first joint very short, not being longer than broad; the second is very broad, and forms a long ellipse, having the upper margin furnished with four fas- ciculi of hairs; the third joint is scarcely as long as the second, very much more slender, slightly curved, and of equal breadth throughout; the underside is fur- nished with a few hairs, commencing near the middle, and increasing in length towards the apex. The foot- jaws have the finger long and slender; the sixth joint, or hand, is short; the wrist is longer than the hand and finger together, but the joint anterior to the wrist is very short, and carries a large squamiform plate, arcuate upon the outer, and straight upon the inner side, armed with six slightly-curved simple teeth, the most anterior K 130 GAMMARIDA. of which is fixed below the apex of the plate; the third joint is likewise formed into a squamiform plate, much smaller and more rounded than the preceding, and fur- nished at the apex with a few plumose hairs. The arms are long and slender, and differ but little from each other. They are very imperfectly subchelate. The first pair are rather the more robust of the two; the hand is much shorter, and has the inferior margin more convex; the palm is very oblique, and not defined; throughout the whole of the inferior margin, including the palm, the joint is furnished with fasciculi, or rather, short rows of hairs, most of which are short and simple; but there exists one or two in each fasciculus much longer than the rest, straight and plumose: the wrist is longer than the palm, and has the inferior margin furnished with several short transverse rows of simple hairs: the finger is half the length of the hand, and is tipped with an unguis or nail, and armed upon the inner side with three or four strong spines, furnished with a serrated or spinous edge. The second pair of arms are rather longer than the first: the wrist is fur- nished with long plumose hairs, planted in short trans- verse rows, laterally to the inferior margin; the hand is long, and of nearly equal breadth throughout, without any distinguishable palm, the inferior margin is fur- nished with several short transverse rows of simple and plumose hairs; the finger is but one-fourth the length of the hand,—it is unguiculate, and has the inner margin armed with five or six small spines. The third and fourth pairs of legs resemble each other, and differ in form from those of other Amphipoda, the fourth joint being long and broad, making a long ellipse, convex upon the outer, and flat upon the inner surface, and AMPELISCA GAIMARDII. 131 having the posterior margin fringed with long plumose hairs ; the wrist is short, scarcely longer than broad, and having the posterior margin fringed with long plumose hairs; the foot is three times as long as the wrist,—it has the margins almost parallel, tapering towards the distal extremity; the outer margin, towards the distal ex- tremity, has long plumose and a few short simple hairs ; the inner has, at the same extremity, four or five short stout spines: the finger is longer than the hand, very slender, and almost straight; it is capable of impinging laterally against the inner margin of the hand, the apex reaching beyond the wrist. The fifth pair of legs have the second joint dilated, oval, being enlarged as much anteriorly as posteriorly ; the fourth and fifth joints are subequal in length and size; the latter terminates ab- ruptly, and has the extremity furnished with five or six short blunt spinules, subapically tipped with a single cilium, and a few long hairs, which have their margins, for nearly the distal half, serrated deeply; the foot is much narrower than the wrist, but is quite as long,—it has the margins almost parallel, the extremities being a little narrower than the diameter of the middle of the joint; the anterior margin is furnished with a row of equidistant, short, obtuse-pointed spines, subapically tipped with a single cilium; towards the extremity of the foot the spines gradually increase in length and in sharpness, until on the apex they pass into the character of hairs; the posterior margin has the distal half mi- nutely crenulate, and armed with three spines, which gradually increase in length and strength the nearer they approach the finger, in the last of which the sub- apical cilium has increased in strength until it has be- come as important as the primary division; the finger K 2 132 GAMMARIDA. articulates towards the posterior margin of the foot, and is directed backwards, contrary to the usual plan in the Amphipoda ; it is short, strong, and sharp, and furnished on the outer surface with a few minute hairs. The sixth pair of legs resemble the preceding, except that the se- cond joint is larger. The seventh pair differ from all the preceding: the second joint is very long; the plate is long-ovate, broader below than above, and postero-infe- riorly produced to the extremity of the next succeeding joint; the foot is long-ovate, and furnished at the distal extremity with a few hairs and spines; the finger is broad, flat, straight, and lanceolate: near the posterior margin is a longitudinal row of circular spots. The caudal appendages are unequal in length; the antepenultimate have the branches longer than the peduncle; the lower branch is simply styliform, the upper is slightly longer, of the same form, but having the upper margin fringed with a row of equidistant spines. The penultimate pair have the peduncle with the upper margin spinous; the branches are subfoliaceous, and curved so as to fit one against the other, and both have their margins thickly fringed with equidistant sharp spines. The ultimate pair are likewise subfoliaceous: the lower branch has the lower margin fringed with spines, and the distal extremity of the upper is furnished with simple hairs; the upper branch is broader than the lower, and has the under surface hollowed, to admit of the under branch being closely pressed against it; it has only the distal in- ferior margin furnished with hairs. The middle tail- piece is longer than the peduncle of the last pair of caudal appendages, narrow, and divided to nearly two- thirds of its length, and the lateral margins are bent to an angle. AMPELISCA GAIMARDII. 153 The skin, as examined beneath the microscope, is very transparent; it is free from any trace of its cell- origin; itis moreover perforated by pores of different sizes, which ap- pear to pass in a waving line directly through the tissue. The colour of the animal is hyaline white, having a blush of rose-colour on many parts of the body, par- ticularly the extremities, and the posterior segments of the body; the extremities of some of the joints of the peduncles of both pairs of antennz are distinguishable by a distinct spot of red. We have kept several of this species in tanks, but they seldom live long, and imme- diately that they are placed in the vessel, dart to the bottom and hide themselves from view, (a peculiarity probably dependent on the structure of the eyes,) so that we have not been enabled to obtain any knowledge of their peculiar habits. The species was first named by Kroyer from an Arctic specimen ; but it is very common all round our coast, in some few fathoms of water, and, we believe, generally in muddy ground. Its long proboscidiform head appears to be peculiarly adapted for burrowing beneath the softer bottoms of the sea, and the character of its eyes also indicates a habitat where organs of vision are but little required. The mandibles, with their tearing processes, (unlike the smooth incisive margins in Lysianassa,) sug- gest a carnivorous rather than a vegetable-feeding habit, decaying animal matter and small creatures found in the mud being probably its food. We have received specimens from the Rev. Geo. Gor- don, taken in the Moray Frith; off the Island of Skye, dredged by Mr. Barlee; Rishbank, Dublin Bay, from 134 GAMMARID. Professor Kinahan; off Fowey, taken by Mr. Wells, of the Admiralty Survey; and in Plymouth Sound it has been dredged by Mr. T. P. Smyth, and ourselves. Costa procured his specimen, which, as far as his im- perfect description will enable us to judge, we consider to belong to this same species, upon the coast of Naples. It has also been dredged from twenty fathoms deep, at the entrance of Belfast Bay, by Messrs. Hyndman and KE. Goodsir, at the beginning of the month of October. These last are in the Collection of the Belfast Museum. Recently it has been taken in the Shetlands by the Rev. A. M. Norman and Mr. J. G. Jeffreys in Outer Skerries Harbour, in from one to two fathoms; near Whalsey Lighthouse, in forty fathoms; and sixty miles east of Shetlands, in from seventy to ninety fathoms of water. The accompanying vignette of Inch Abbey, co. Down, was kindly sketched for us by Mrs. Campbell. AMPELISCA BELLIANA., 135 AMPHIPODA. AMPELISCIDES. NATATORTA., AMPELISCA BELLIANA. Specific character. Third segment of the pleon having the posterior mar- gin deeply bisinuated on each side. Superior antennze shorter than the peduncle of the inferior. Length rather more than } inch. Tetromatus Bellianus. Spunce Barn, Brit. Assoc. Rep. 1855, p. 58. Ann. Nat. Hist. xix. 139. Cat. Amph. Brit. Mus. p. 93, pl. xv. fig. 3. Waite, Hist. Brit. Crust. jenn lizfale Tuts animal, in its general appearance, resembles 4. Gaimardii, but may be distinguished from it by the contour of the posterior margin of the tenth segment after the head; on each side it is waved, having a deep indentation near the upper part, a prominent lobe about the middle, a second indentation below the lobe, beneath which the inferior margin is produced to a sharp slightly upturned process, or tooth. The superior antennze are not longer than the head. The first joint of the peduncle is very short, scarcely longer than broad; the second joint is about twice the 136 GAMMARID. length of the first, and more slender; the third is very short ; the flagellum is scarcely as long as the peduncle. The inferior antenna are about one-third the length of the animal; the peduncle is longer than the superior antenne, of which the penultimate joint is twice the length of the ultimate; the flagellum is scarcely as long as the peduncle. The mandibles have no appreciable distinction from those of A. Gaimardi. The foot-jaws have the antepenultimate joint reaching scarcely to the extremity of the squamose process of the preceding joint; the penultimate joint is nearly as long as the one before it, and itself is longer than the finger, which terminates in a sharp nail; the spines upon the squamose plate differ from those in A. Gaimardii in form as well as in length; they are eight in number, and rapidly increase in size from the base to the top of the plate; their form is that of a lancet-blade, slightly hooked at the point, and narrowed at the base; the apex of the plate is crowned with three hairs, or long spines. The arms and two following pairs of legs re- semble those of A. Gaimardii, as well as the fifth pair of legs, except that the second joint is quite as broad as long. The sixth pair have the second joint quad- rate, with the postero-inferior margin slightly produced downwards. The second joint of the last pair is not so much postero-inferiorly produced as in A. Gawmardii, and the penultimate joint is broader, The caudal ap- pendages scarcely differ from those of the other species, except that the branches are not proportionally so long, and their margins are less numerously and regularly fringed with spines. The terminal scale is long, narrow, and split from the apex nearly to the base, and the late- ral margins are bent to an angle. The colour scarcely differs from that of A, Gaimardii, AMPELISCA BELLIANA., 13% but we have taken one or two specimens with some beautiful stellate crimson spots, as well as several black ones near the organs of vision. We first procured this species from our valued cor- respondent, the Rev. Geo. Gordon ; since which we have received it from Mr. Edward, both having taken it in the Moray Frith. It has also been dredged by us in Ply- mouth Sound; and in the British Museum are specimens which Mr. Barret has taken in the North Atlantic. This species is much more rare than A. Gaimardi, and apparently less extended in its geographical range. Pro- fessor Liljeborg has taken, at Kullaberg, on the coast of Norway, a species, A. macrocephala, which, from his de- scription, bears so close resemblance to the present, that we should have regarded them as identical, but that he says the fourth segment of the pleon is carinated, and the sixth is posteriorly obtusely bidentate. Mr. Stimp- son has also recorded a species, A. ingens, taken at Grand Manan, on the coast of America, which somewhat re- sembles A. Belliana, but differs in having the margin of the sinuated segment less deeply waved, the greater length of the superior antennz, the more perfectly de- veloped form of the first pair of hands, and lastly, in that truly American feature, its large size—being three times as large as the European form. M. Holboll has also found this last species in forty fathoms of water, on the coast of Greenland. The species is inscribed with the name of Professor Bell, F.R.S., &c., whose work on the “ British Stalk- Eyed Crustacea” has greatly tended to the study of this branch of Natural History, and to whom we are bound to offer our warmest thanks for the assistance he has afforded us, with his wonted urbanity, in the prepara- tion of this work. 138 GAMMARIDA. AMPHIPODA. PHOXIDES. NATATORIA. Subfamily—-PHOXIDES. Pontoporeides. Dana, Un. St. Explor. Exped. p. 912. Spence Bare and Westwoop, Rep. Brit. Assoc. 1855, p. 21. Phowides. Spence Bars, Ann. Nat. Hist. 1857, vol. xx. p. 525. Cat. Amph. Brit. Mus. p. 97. Cephalon produced in advance, more like a hood thana rostrum. Inferior antenne situated considerably posterior to the superior. Tuts subfamily offers several aberrant characteristics. The head is generally produced far in advance of the antenne, looking like a hood hanging over the basal portions. ‘The eyes in the most typical genera are almost rudimentary, and exist in the form of an orbicular mass of pigment, deeply seated in the head, without any lenses observable on the surface. The antennz are situated nearly in the same plane, the one behind the other. The peculiar form of the head, together with the im- perfect character of the eyes, induce us to believe that these animals dwell where vision is not essential, some burrowing in sandy or muddy bottoms, while others ex- hibit features of a parasitic character.* The genus Pontoporeia being closely allied to Anonyx in the preceding sub-family, we have been compelled to reject Dana’s sub-family name, and have employed in its stead a name derived from one of the most typical of its genera. * The recent observations of Mr. Spence Bate on the development of some species of Hyperina induce us to believe that there is a nearer connection between this sub-family and the latter than has hitherto been assigned to them. PHOXUS. 13 AMPHIPODA. PHOXIDES. NATATORIA, Genus—PHOXUS. Kroyer. Phozvus. Kroynr, Tidsk, vol. iv. p. 150. Generic character. Cephalon considerably produced anteriorly to a point, not much depressed. Superior antenne having a secondary appendage. Maxillipedes subpediform. Gunathopoda subchelate. Posterior pair of pereiopoda shorter than the others. 'Telson double. Tuts genus may be taken as the type of the sub- family. It has the head considerably advanced in front, and produced into a blunt point, but which is not much depressed. We have not observed the eyes, but Stimp- son speaks of them as being two in number, but they are very imperfect, and generally white, and disappear soon after death. The superior antennz carry a se- condary appendage, which is generally very long. The mandibles are furnished with an appendage. The foot- jaws have the squamiform plates but little developed ; thus bearing a considerable resemblance to the ordinary walking legs. The hands are subchelate, and nearly of the same size. The last pair of walking feet are very short, being considerably shorter than any of the others. The last pair of caudal appendages are biramous, and the terminal plate is double. 140 GAMMARIDA. AMPHIPODA. PHOXIDES. NATATORIA. PHOXUS SIMPLEX. Specific character. Superior antenne scarcely reaching beyond the ex- tremity of the cephalon. Inferior antenne nearly three times as long as the superior. Three anterior coxe having four simple hairs near the hinder angle of the inferior margin. Length, 3 inch. Phoxus simplec. Sprnce Bare, Ann, Nat. Hist. 2 ser. 1857, vol. xx. p. 525. Cat. Amph. Brit. Mus. p. 97, pl. xvi. fig. 1. Phoxus Kroyer. Svrnce Bare, Synopsis, &c. Ann. Nat. Hist. Feb. 1857, 2 Ser. xix. p. 152. Brit. Assoc. Rep. 1855, p. 58 (not of Stimpson in Proc. N. Hist. Soc. Boston). WHITE, Hist. Brit. Crust. p. 173. Tuis species has the dorsal surface of the head con- siderably produced, and gradually narrowed, without being curved downwards, and with the apex obtusely rounded. The eyes have not been observed, owing pro- bably to the circumstance of the animal not having been examined until some time after death, whence we are led to suppose that they are imperfect in their structure. The superior antennz are very short, scarcely reaching beyond the extremity of the overhanging head; the PHOXUS SIMPLEX. 141 peduncle is very short; and the flagellum is scarcely longer ; the secondary appendage consists of but three articuli, and is nearly as important as the primary, which is formed of but four. The inferior antenne are about as long again as the head, and three times as long as the superior; the peduncle does not reach as far as the apex of the projecting head; and the flagellum, which consists of about ten or twelve articuli, has each articu- lus almost as broad as long. The coxe of the arms and first two pairs of walking legs are very large, broad, and much deeper than the respective segments of the body ; the three anterior are furnished, towards the posterior portion of the inferior margin, with four simple hairs, which number appears to us to be persistent, as five are to P. Holbolli, and a greater number to P. plumosus ; the arms are subequal, the first pair being rather the smaller; the wrist is short, and the hand twice as long as broad; the inferior margin runs parallel with the superior, but is not quite so long; the palm is slightly oblique, and defined by a small tooth at the inferior angle; the finger is of the same length as the palm. The second pair of arms vary but little in form from the preceding ; the hand is a little larger, it is rather broader towards the base, both margins are convex, the inferior is about one-third shorter than the superior ; the palm is much more oblique than that of the first pair, it is also slightly convex, and defined by a larger tooth at the inferior angles: the finger is slightly curved, and is about the length of the palm. The walking legs are rather slender. The first two pairs have the fingers rather long and straight. The fourth pair of these legs are longer than the third, but the fifth are much shorter than either, and apparently useless; the squamiform thigh is larger than that of the preceding legs, and 142 GAMMARIDH. broadest below; the rest of the leg is only equal in length to that of the thigh. ‘The antepenultimate pair of caudal appendages have the plates as long as the peduncle, those on the two posterior pairs are shorter, and the middle piece consists of two narrow, unarmed plates, with a few fine spines at the extremity. The only place from which this species has been re- ceived is that of Plymouth Sound, where it was taken by us with the dredge. The vignette is by Mitchell, and represents the Mew Stone, Plymouth Sound. PHOXUS HOLBOLLI, 143 AMPHIPODA. PHOXIDES, NATATORIA. PHOXUS HOLBOLLI. Specific character. Superior antenne having the peduncle reaching as far as the extremity of the cephalon; flagellum as long as the peduncle; secondary appendage half as long as the primary. Inferior antenne scarcely longer than the superior. Gnathopoda subequal; propoda quadrate ; palm but slightly oblique; three anterior cox having each five simple hairs upon the inferior margin, towards the hind-angle. Length } inch. Phoxus Holbolli. Kroyrr, Tidsk. vol. iv. p. 150. Spence Bare, Synop. &e. Ann. Nat. Hist. Feb. 1857, p. 58. Cat. Amph. Brit. Mus. p. 98, pl. xvi. fig. 2. Wuirr, Hist. Brit. Crust. p. 173. THE general appearance of the animal much resembles that of P. simplex, but the antennz are longer, the su- perior pair are nearly as long as the head, and extend considerably beyond the extremity of the cephalon; the peduncle reaches quite to the anterior margin of the pro- jecting hood; the first joint of the peduncle is tolerably long, but almost hid beneath the walls of the head; the 144 GAMMARIDA. second and third joints are small; the flagellum consists of seven articuli, and is rather longer than the peduncle. The secondary appendage is about half the length of the primary. The inferior antenne are slightly longer than the superior ; the peduncle extends beyond the peduncle of the superior; the flagellum has the first four or five articuli very short, the remainder irregularly increasing in length. The foot-jaws nearly resemble true legs, and terminate in a short sharp-pointed finger, retaining the characteristic of their true nature only in two small scale- like processes, springing from the second and third joints, —the joints are all of the same length. The large squa- mose coxee of the four anterior pairs of legs are deeper than their respective segments, the three anterior having the posterior half of the inferior margin furnished with five hairs, the hindmost of which is short. The coxe of the three posterior pairs of legs are much shorter than those of the preceding pairs. The first two pairs of legs are subequal, tolerably strong, each having a hand of nearly similar form; that of the first pair is almost quadrate, the margins nearly parallel, the palm is some- what oblique, slightly convex, and slightly serrated, de- fined by a short sharp tooth. Those of the second pair are rather longer, and have the palm defined by a longer and sharper denticle; the fingers are sharp and slightly curved. The next two pairs of legs are slender; the fifth pair are tolerably robust, but not very long, having the second joint considerably dilated posteriorly; the sixth pair are longer than the fifth, very similar in form. The seventh also resemble them, but are very much shorter, the third and following joints being scarcely as long as the largely-dilated second joint ; all the legs after the first two have the finger very short. The three pairs of natatory appendages are not very long, and are pro- PHOXUS HOLRBOLLI. 145 tected by the deep lateral walls of the segments to which they are attached. The caudal appendages terminate subequally, the posterior pair being a little the longest ; the two preceding have the styliform rami equal in length, and free from hairs; the last pair have the peduncle short, and the rami unequal, the outer branch being one-third longer than the inner. The middle tail- piece is double, each division being long and tapering, and the apex tipped with a few small hairs. The animal, as far as we have been able to judge from recently-dead specimens, is transparent and colourless ; nor have we been able to detect any eye. The surface of the skin is sparsely covered with small hairs, some of which are simple, while others have a club-shaped apex. Judging only from Kroyer’s description, we have but little doubt that this species is identical with that which he named after M. Holboll. We first found it as British by dredging it in Ply- mouth Sound; it has since been sent to us from Banff by that indefatigable lover of nature, Mr. Edward. 146 GAMMARIDZ. AMPHIPODA. PHOXIDES. NATATORIA. PHOXUS PLUMOSUS. Specifie character. Superior antennz longer than the cephalon. Inferior antenne scarcely as long as the superior. Gnathopoda having the propodos long-ovate ; palm very oblique. Hairs on the margin of the coxe, as well as on the legs, plumose. Length, ;4, inch. Phoxus plumosus. Kroyer, Tidskr. vol. iv. p. 150. Spence Bars, Rep. Brit. Assoc. 1855, p. 58. Ann. Nat. Hist. 2 ser. xx, p. 525, Feb. 1857. Cat. Amph. Brit. Mus. p. 99, pl. xvi. fig. 8. Wauurr, Hist. Brit. Crust. p. 173. Phoxus fusiformis. Stimpson, Mar. Invert. Grand Manan, p. 57. Tus animal in its general aspect much resembles the other species of this genus, but the projecting surface of the head is less acute. We have not been able to make out the eyes; but Mr. Stimpson says, that in the Ameri- can specimen (which we consider, from his description, to be synonymous with the British) they are white. The PHOXUS PLUMOSUS. 147 superior antennz have the peduncle reaching as far as the extremity of the head; the first joint is very long, and reaches nearly to the anterior margin of the head, —it is furnished upon the inferior margin with three short plumose hairs; the second joint is very short, being but little longer than broad, inferiorly slightly dilated, and armed with five simple hairs; the third joint is shorter than the second, and more slender; the fla- gellum is slender, and as long as the peduncle, consisting of seven or eight articuli, of which the first is as long as three others; the secondary appendage is slender, and nearly as long as the primary, and consists of six articuli. The inferior antennz are rather shorter than the superior; the peduncle reaches as far as the ex- tremity of the first joint of the peduncle of the su- perior; the penultimate joint is the longest, and is inferiorly dilated into a squamiform process, with a convex margin, and fringed with several plumose hairs, as is also the antero-superior margin; the last joint is short and slender; the flagellum is more slender still,— it is shorter than the peduncle, and consists of seven or eight articuli, of which the first is as long as the two succeeding. The mandibles are short, (having the in- cisive margin armed with denticles,) and furnished with a long two-jointed appendage; the distal joint being longer than the basal, terminating obliquely and carry- ing a row of closely-set hairs, which increase in length towards the extremity. The foot-jaw bears a consi- derable resemblance to an ordinary leg, but is distin- guishable by a small squamiform process, developed both from the third and fourth joints, which are sub- equally short; the fifth is long, and fringed upon the inner margin with hairs; the sixth joint is scarcely half as long as the fifth, fringed like the preceding, the fringe L2 148 GAMMARIDA, short, sharp, and slightly curved. The four anterior coxz are large, quite as deep as the segments of the body to which they are attached respectively, and each has the inferior margin fringed with a row of equidistant, soli- tary, short, plumose spines. The first pair of legs are slender, tolerably long, having the metacarpus and wrist fringed upon the inferior side with a few plumose cilia; hand long, narrow, tapering ; palm two-thirds the length of the hand, exceedingly oblique, defined by a small obtuse denticle, and fringed with a row of equidistant fine cilia: finger long and slender, as long as the palm, and nearly straight. The second pair of legs resemble the first, but are scarcely as large, and the palm is slightly waved, and not so distinctly defined, and the finger appears to be scarcely as long as the palm. The third and fourth pair of feet are slender, fringed with cilia, both plumose and simple, having the hand straight and unarmed; the finger as long as the hand, straight, stout, and furnished with a nail at the extremity; on the distal extremity of the hand, on each side of the finger, stands a moveable spine, as stout and long as the finger, apparently having the power of being compressed to- gether, each fitting into a lateral groove in the finger, thus forming a feeble and insufficient nipper. The fifth pair of legs are long, slender, and plumose, the coxa is short, and the thigh tapering, with a posterior concave margin to the distal extremity; all the joints after the knee are subequal in length ; the finger is quite straight. The sixth pair of legs resemble the preceding in form, but are nearly half as long again; the joints after the knee are subequally long and slightly plumose; the finger is longer than the hand, straight and styliform. The seventh pair of legs are very short, reaching only to the middle of the metacarpal joint of the sixth pair of PHOXUS PLUMOSUS. 149 legs; the coxa is very short, but the thigh is largely dilated, and postero-inferiorly produced to a blunt point, reaching as far as the wrist; the inferior and posterior margins are slightly crenated, each crenulation emitting a solitary hair; all the joints, except the finger, (which is long, straight, and styliform,) are subequally short. The caudal appendages are free from hairs or spines; they terminate subequally, the antepenultimate pair being slightly the longer, and the penultimate pair the shortest. The branches are subequal, those of the last pair being rather less pointed than those of the two preceding pairs. The central piece is double, but not so long as the peduncle of the posterior pair of caudal appendages. The colour of the animal is corneous and transparent. The structure of the tissue, under the microscope, is seen to be minutely granular. Kroyer, in his description, says that a few spines exist upon the third and fourth joints of the peduncle of the inferior antenne in P. Holbolli, but that they are absent in P. plumosus. In one specimen of P. Holbolli the hairs upon the inferior antennz are scarcely robust enough to be called spines; whereas in P. plumosus there are a few plumose hairs, of which Kroyer makes no mention. In other respects the animals appear to cerrespond with Kroyer’s description, and we do not feel justified in sepa- rating them upon such immaterial distinctions. The only difference between P. plumosus and Stimpson’s specimen of P. fusiformis consists in the American specimen having what the author of its description calls ‘‘more nails on third and fourth legs.” Now these so-called ‘ nails” we take to be the long lateral spines that impinge against the sides of the fingers of the third and fourth pairs of legs. 150 GAMMARIDA, It was first taken by Holboll on the coast of Green- land, from whence the great northern currents probably drifted it to the shores of America: for, generally speak- ing, the Crustacea of the eastern coast of America are very distinct from those of the western coast of Eu- rope; and in instances where they may be found to be identical, (as we believe to be the case with this species,) they are essentially Arctic forms, which yield to the opposite shore of each continent some few wandering specimens. We have taken it with the dredge from Plymouth Sound, from which specimen our figure was drawn and described, but the figure of the caudal appendages was drawn from another specimen. Mr. Barlee has taken it while dredg- ing in the Shetlands, as have also very lately the Rev. A. M. Norman and Mr. J. Gwyn Jeffreys. The speci- men which Stimpson describes as distinct, but which we have incorporated with this species, was taken by him with the dredge on coarse sandy bottoms, in the laminarian and corralline zone on the coast of the Isle of Grand Manan, U.S., North America. GRAYIA, 151] AMPHIPODA. PHOXIDES. NATATORIA. Genus—GRAYIA. Grayia. Spence Bare, Cat. Amph. Crust. Brit. Mus. p. 101. Generic character. Cephalon anteriorly produced. Eyes two. Superior antenne without a secondary appendage. Gna- thopoda subchelate. Pereiopoda subequal. Posterior pair of pleopoda biramous. Telson squamiform. THE head is only moderately produced in front, and does not terminate ina point. The eyes are two, one on each side of the head, in the normal position of those organs. The superior antennz are not furnished with a secondary appendage. The inferior antennz are not so robust as the superior. The three posterior pairs of walking legs are strong and subequal in length, and terminate in sharp-pointed fingers. The last caudal appendage is double-branched, and the middle tail-piece is squamiform and apparently simple. We consider this genus to bear a close affinity to Odiceros Kr., from which it is distinguished by the shortness of the last pair of the walking legs, which, in this genus, are not longer than the preceding pair. The animal possibly may be parasitic; but if it pos- sesses similar habits to Darwinia, it differs generically ‘in the size of the arms, the form and depth of the coxa, the less dilated character of the body, and the absence of the unusual character of the third segment of the tail being considerably less deep than the second, This genus is named in compliment to Dr. J. E. Gray, F.R.S., &c., the indefatigable keeper of the Zoological Collection of the British Museum, to whose zeal its pre- sent efficient state is mainly owing. 152 GAMMARID&. AMPHIPODA. PHOXIDES. NATATORIA, GRAYIA IMBRICATA. Specific character. Three anterior segments of the pleon posteriorly elevated. Eyes large. ee Length, ,, inch. Grayia imbricata. Sprence Barr, Cat. Amph, Crust. Brit. Mus. p. 101, pl. xvi. fig. 4. Tue head is anteriorly produced, and rounded in front, but not extending to a point. The three seg- ments of the anterior part of the tail are each posteriorly raised, giving, when viewed laterally, an imbricated ap- pearance to the dorsal margin, a circumstance that suggested the specific name of the animal. The eyes are rather large, tolerably round, and very black. The superior antennz are not longer, but stouter, at the base of the peduncle than the inferior. The inferior are more slender and less tapering than the superior, and equal in length to the head and the first three segments of the body. The coxe are not so deep as the body, and the four anterior are equal in size. The first two pairs of legs are subchelate ; the hands are subovate, the palms GRAYIA IMBRICATA. 153 oblique, and the fingers short and curved. The walking legs are nearly all of the same length, and each termi- nates in an evenly-curved finger, sub-apically furnished with a single short hair. The three caudal appendages are subequal in length. This species was first sent to us by our friend Mr. W. Webster, who dredged it in Falmouth Harbour. We have since received it through the kindness of the Rey. A. M. Norman, (who has forwarded to us his entire col- lection of Edriophthalmous Crustacea for examination,) having been taken by Mr. Alder off the coast of North- umberland: this northern specimen appears to possess the imbricated character, more strongly expressed than in that from Falmouth. 154 GAMMARID. AMPHIPODA. PHOXIDES. NATATORIA. Genus—WESTWOODILLA. Westwoodilla. Spence Bars, Cat. Amph. Brit. Mus. p. 102. Westwoodea (pars). Spence Barn, Rep. Brit. Assoc. 1855, p. 58. Westwoodia. Synop. Amph. Ann. Nat. Hist. 2 ser. xix. p. 139, Feb. 1857. Wuttr, Hist. Brit. Crust. p. 172. Generic character. Cephalon anteriorly produced. Eyes con- fluent. Superior antenne without a secondary appendage. Mandibles appendiculated. First pair of gnathopoda subche- late. Second pair* not subchelate. Posterior pair of pereio- poda longest. Posterior pair of pleopoda biramous. Telson squamiform. Tue head is produced anteriorly as in Phowxus, but more depressed. ‘The eyes are associated, so that they appear as a single organ, imbedded within the head. The antenne are simple, the superior having no secon- dary appendage. The mandibles are furnished with an appendage. ‘The first and second pairs of legs are sub- equal; the first pair are subchelate,—the second are not so, but terminate in a finger, which does not fall back against the hand. The walking feet gradually increase in length, but the last is considerably longer than the rest. ‘The posterior pair of caudal appendages are bi- ramous, and the terminal plate is squamous. This genus resembles Monoculodes of Stimpson, but differs from it in having the hands less perfect in their prehensile character. The name Westwoodea proposed in the “ Report on the British Edriophthalma” required to be changed, in consequence of its having been previously adopted by Dana for a genus of ENTomostracous Crus- tacea, and by Brullé for a genus of Hymenoptera. WESTWOODILLA CQ@CULA. 155 AMPHIPODA. PHOXIDES. NATATORIA. WESTWOODILLA CCCULA. Specific character. Antennz subequal. A central nucleus to each cell in the microscopical structure of the skin. Length, 3 inch. Westwoodilla cecula. SpuncEe Bate, Cat. Brit. Amph. Brit. Mus. p. 102. Westwoodea ceculus. Spence Barn, Rep. Brit. Assoc. 1855, p. 58. Westwoodia cacula. Sprnce Bates, Synop. Ann. Nat. Hist. 1857, 2 ser. xix. p. 139. Wuure, Hist. Brit. Crust. p. 172. Tue animal has the head considerably produced, and anteriorly depressed, having the frontal margin rounded. The eye appears to stand upon a process of the head, between and above the superior antenna, but not to be in connection with the projected hood-like process. It is of a dull red-purple colour, but without a clearly-de- fined outline, a circumstance that has Jed to the selection of the specific name, as it has every appearance of being an imperfect organ of vision. The antennz are nearly of equal length; the superior are scarcely longer than the head,—they have the first two joints of the peduncle 156 GAMMARIDE. nearly the same length, but the third is much shorter and slighter, and the flagellum is not more than twice the length of the last joint of the peduncle. The in- ferior antennz are but little longer than the superior; the joints of the peduncle are more nearly equal in length, but the last is more slender than the preceding ; the flagellum is but little longer than the last joint of peduncle. The mandibles appear to be very strong,— they are exceedingly hollowed; the incisive margin is smooth, and has the extremities rounded ; within there is a second plate, but of much smaller dimensions ; nearer the head. stands a very large molar tubercle. The appendage to the mandible is three-jointed, the second, longer than either of the others, is triangular in its diameter, and strongly curved. The foot-jaws are short and strong,—the third joint is furnished with a large squamous plate, the outer margin of which is rounded, and the inner straight, fringed with spines and small hairs alternately, and increasing in length; the fifth joint is broad, longer than the fourth or sixth, which last is ovate, and supports a strong finger. The first pair of arms are subchelate,—they are not very long, and have the wrist as long as the hand; the infero- anterior angle is anteriorly produced into a rounded lobe, the inferior margin of which is fringed with a few hairs ; the hand is elongate-ovate, the palm occupies nearly the whole length of the inferior margin, and is imperfectly defined by a small tooth, and fringed with a series of equidistant cilia of equal length; the finger appears to be scarcely as long as the palm,—the whole organ is but inefficient in its prehensile powers. The second pair of arms are about the same size as the first, but they ap- pear to possess no prehensile capability; the hand is longer than the wrist, and dilated on the superior mar- WESTWOODILLA C@CULA. 157 gin, which is furnished towards the distal extremity with a copious brush of hair ; the finger is straight, and appears not to have the capability of being inflexed against the hand. ‘The first two pairs of walking legs are uniform in shape, and carry a tuft of hair upon the antero-distal extremity of the sixth joint. The fifth pair of legs are longer and more robust than the sixth. The coxa has the anterior lobe much deeper than the posterior. The sixth pair of legs are rather longer than the preceding, and more slender; whilst the seventh is considerably longer and still more slender, having the foot consider- ably increased in length, and the finger very long, being longer than the foot, and quite straight. The caudal appendages are nearly equal in length; the last pair are rather more foliaceous than the two preceding pairs ; and the terminal plate is squamous, round, and dorsally concave. The animal is very transparent, being slightly corneous ; under the microscope the structure of the skin appears like a series of cells, overlapping each other like the scales of fish ; the margin of each scale is defined by a double row of short straight lines or spots, and a black spot marks the centre of each scale. The whole surface of the skin of the posterior part of the animal is, moreover, superficially covered with a fine fur, formed of processes of the integument, broad at the base, and exquisitely fine at the apex. The anterior portion of the animal is free from this fur. The specimen from which our figure was taken is a female, and laden with ova. We took it from among some trawl-refuse, brought in from the neighbourhood of the Eddystone. It has since been sent to us from the Moray Frith, by the Rev. G. Gordon; and from Banff by Mr. Edward. 158 GAMMARIDA. AMPHIPODA. PHOXIDES. NATATORIA. WESTWOODILLA HYALINA. Specific Character. Hye prominent. Superior antenne shorter than the peduncle of the inferior. In the microscopic structure of the skin there is no central spot or nucleus to each cell. Length $ inch. Westwoodilla hyalina. Srrnce Barr, Cat. Amph. Brit. Mus. p. 103, pl. xvii. fig. 5. Tuts animal bears a considerable resemblance to the last species, but differs in several more or less important details. The eye is more clearly defined in form, and situated so closely beneath the skin, that it is raised upon the outer surface. It is long-ovate, and situated in the centre of the hood-like projection of the head. The superior antenne are a little longer than the head, and have each joint of the peduncle gradually decreasing in length; the flagellum, which only consists of five or six articuli, is about the length of the last two joints of the peduncle. The inferior antenne have the peduncle longer than the superior; the last three joints are sub- equal in length, and the flagellum, which consists of five WESTWOODILLA HYALINA. 159 or six articuli, is not longer than the last joint of the peduncle. The arms are subequal, the first pair having the wrist inferiorly produced, and the hand long-ovate ; while the second have the hand furnished, upon the anterior distal extremity, with a brush of hair; both arms, in fact, closely assimilate to those of W. cecula, whilst the rest of the animal approximates so nearly to that species, that we should have described it as being but sexually different, had there not been a very decided alteration in the microscopic appearance of the skin. Like the previous species, most of the body of the animal is covered by a fine fur, which, we think, is somewhat of a finer character than that of W. cecula, and deeper in the structure may be observed the arrange- ment of the cells on a similar plan. Lach cell is marked by a double row of elongated dots, and regularly ap- proaches the adjoining cell, like chain-armour; but the black spot which occupies the centre of each cell, and is so conspicuous in the previous species, is not visible in this, which therefore becomes still more transparent and clear. In fact, the species, whilst living, is scarcely per- ceptible, but for its great purple eye. We procured this species from the refuse of trawlers, who had been fishing near the Eddystone Lighthouse. 160 GAMMARIDA. AMPHIPODA., PHOXIDES., NATATORIA, " GEDICEROS. Gdiceros. Kroynr, Tidskr. iv. p. 155 (1842-8). Cdicerus. Dawa, U. 8. Explor. Exped. p. 933. Spence Bare, Cat. Amph. Brit. Mus. p. 103. Cephalon produced anteriorly. Eyes confluent. Superior antenne without a secondary appendage. Gnathopoda sub- chelate. Posterior pair of pereiopoda very long and slender. Tue head is produced and depressed anteriorly. The eyes are confluent, and situated before the antenne. The upper antenne are without a secondary appendage. The arms are subchelate: the first pair area little longer than the second. “ The first two pairs of walking legs are strong, and the last pair is very long and slender, almost filiform.” (Kroyer.) The only specimen of this genus that we have seen is imperfect; we, therefore, can only assume that the absent parts, like those present, correspond generically with the description given by Kroyer. In our specimen the eyes are visible, whereas Kroyer describes the ani- mal as having none, but marks the assertion with a doubt. This genus is in very close connection with West- woodilla, from which it appears to differ only in having the second pair of gnathopoda subchelate. It is to us a question of some doubt whether the species described by Dana belong to this genus. They certainly differ in the absence of the prolonged rostrum, and in the possession of two distinct lateral eyes. (EDICEROS PARVIMANUS. 161 AMPHIPODA. PHOXIDES. NATATORLIA. CEDICEROS PARVIMANUS. N.S. Specijic character. Eyes confluent, placed near the apex of the rostrum. Superior antenne as long as the cephalon. Inferior antenne one-third longer. First pair of gnathopoda longer than the second. Length, J; inch. Tue head is large and deep, being as long as the first four segments of the body, and reaching nearly as deep as the lower margins of the coxz. ‘The eyes are con- fluent, and appear as a single organ, situated at the anterior extremity of the head, where it is produced into a hood-like rostrum. ‘The superior antennz are scarcely longer than the head, and the flagellum is scarcely shorter than the peduncle. The inferior an- tenne are half as long again as the superior, and the peduncle is about the same length as the flagellum. The first pair of legs are simply subchelate, and not largely developed; the wrist is quite as large as the hand, and has the infero-anterior angle produced an- teriorly ; the hand is ovate, has the palm oblique, but not distinctly defined, and is armed with strong hairs. The second pair of legs are more slender than the first ; the wrist is quite as long as the hand, and has the infero- anterior margin slightly produced; the hand is long- M 162 GAMMARIDA. ovate, having the palm very oblique, and furnished with a few very slight hairs. The rest of the appendages of the only specimen of this species which we have seen are mutilated. Kroyer in his generic description states that both pairs of hands are very large, which must be assumed to be a specific, rather than a generic character, and hence, since his genus was founded upon the observation of a single species, this character belongs to Gidiceros saginatus alone. In this respect our species differs from that of Kroyer, as neither of the hands can be described as being large, and the second is decidedly smaller than the first. It is in the collection of the Rev. A. M. Norman, having been taken by him, and Mr. J. Gwyn Jeffreys, in from seventy to ninety fathoms of water, sixty miles east of the Shetlands, in the summer of 1861. MONOCULODES. 163 AMPHIPODA. PHOXIDES. NATATORIA. Genus—MONOCULODES. Stimpson. Monoculodes. Stimpson, Marine Invert. Grand Manan, p. 54. SPENCE Bare, Cat. Amph. Crust. Brit. Mus. p. 104. Westwoodea (pars). Spence Bate, Rep. Brit. Assoc. 1855, p. 58. Kréyera. Spence Bare, Synop. &c. Ann. Nat. Hist. Feb. 1857, 2 ser, xix. p. 140 (but not of this work). Generic character. Cephalon produced and depressed ante- riorly. Eyes coalesced into one, situated above and anterior to the superior antennw. Superior antennz without a secondary appendage. Gnathopoda subchelate, carpi antero-distally pro- duced to the extremity of the inferior margin of the propoda. First pair more robust than the second. Second having the propodos longer than the propodos of the first pair. Posterior pair of pereiopoda much longer than the others. Posterior pair of pleopoda biramous. Telson squamiform, entire. Tue head is rounded above, and the anterior dorsal surface is considerably produced and depressed. The eyes are deep-seated, converging together, so as to ap- pear to be but a single organ, placed horizontally above, and still more forward than the base of the superior pair of antenne. The antenna are simple in their character, the superior pair not being furnished with a secondary appendage. The mandibles are furnished with an ap- pendage. The first two pairs of legs are complexly subchelate, having the wrist produced anteriorly along the inferior margin of the hand, which is much longer and not so broad in the second as in the preceding pair of legs. The last pair of legs are considerably longer than any of the other pairs, and terminate in a long M 2 164 GAMMARIDA. straight finger. The last pair of caudal appendages are double-branched, and the terminal plate is squamiform. The genus was first described by Mr. Stimpson, in his ‘* Synopsis of the Marine Invertebrata of Grand Ma- nan,” it which he says that it differs from Cdiceros in the form of the hands. We have not, until recently, had an opportunity of seeing an undoubted specimen of the latter genus. This, however, corroborates our previously- expressed opinion, which was based upon the circum- stance that Kroyer, in his description of the genus, did not in any way refer to the prolonged carpus of the first two pairs of legs: we, therefore, agree with Stimpson, and retain the genus Monoculodes, to which C:diceros appears to be closely allied. Monoculodes assimilates also to Westwoodilla, in which, however, the second pair of legs are not in the least degree subchelate. This genus was first described in this country by Mr. Spence Bate, in “ A Synopsis of the British Amphi- poda,’ under the name of Aréyera, with Westwoodea carinata (Brit. Assoc. Rep. 1855, p. 58) as its type. Being, however, identical with Monoculodes of Stimpson, the name of Kroyera has been sunk for the present genus. In order, however, that the name of the dis- tinguished Danish carcinologist should remain associated with the present class, it has been transferred to a sub- sequent genus. MONOCULODES CARINATUS, 165 AMPHIPODA. PHOXIDES., NATATORIA. MONOCULODES CARINATUS. Specific character. Body having the last two segments, and the tail having the first three segments, dorsally raised into a keel, increasing in size poste- riorly, and ending abruptly in each segment. Length 3 inch. Westwoodea carinata. Spence Barn, Brit. Assoc. Rep. 1855, p. 58 Kréyera carinata. Spence Barr, Synop. Ann. Nat. Hist. Feb. 1857, 2 ser. xix. p. 140. Monoculodes carinatus. SprENce Bate, Cat. Crust. Brit. Mus. p. 104 Tue head is considerably produced anteriorly, and much deflexed. The eye is long-oval, deeply seated, and rather dimly defined, lying in a plane correspond- ing with the dorsal surface. The superior pair of an- tenne do not reach further than the extremity of the peduncle of the inferior pair; their peduncle reaches a little beyond the anterior extremity of the head; and the flagellum is about the length of the peduncle. The inferior pair of antenna are about one-third the length 166 GAMMARIDA. of the animal; and have the last joint of the peduncle as long again as the preceding, and rather longer than the flagellum. The foot-jaws are tolerably robust, and terminate in a triangular hand, the broadest part being near the finger, where it forms a kind of palm, against which the finger, which is extremely curved, is capable of impinging. The first pair of legs are not very long, they have the metacarpus produced inferiorly to a sharp point; and the wrist is considerably produced anteriorly, in the form of a plate, corresponding to the inferior margin of the hand; the hand is oval, having a convex palm obliquely placed, and defined by a solitary, short, obtuse spine,—it is armed throughout its length with a number of short posteriorly-directed hook-like spines, which are flanked by several bunches of straight, un- even, lengthened hairs; the finger is curved, sharp, and free from any armature. The second pair of legs are longer than the first, but are constructed upon the same type; the wrist is anteriorly produced to a much greater length ; the hand is long and narrow, being nearly four times as long as broad; the palm is short, slightly ob- lique, fringed with short, and a few long cilia, and defined by an obtuse rounded angle, beyond which the anterior extremity of the carpus advances; the finger is short, curved, clean, and sharp. The coxz of the five anterior pairs of legs are as deep as the corresponding segments of the body. The third and fourth pairs of legs are formed upon the same type, and closely re- semble each other, and are remarkable for having the hands dilated upon the backs, where they are furnished with a thick brush of hair, a peculiarity which appears to belong to this genus. The fifth pair of legs are much longer than the two preceding pairs,—they have the coxa two-lobed, and as deep as the coxa of the preceding legs; MONOCULODES CARINATUS. 167 of legs; the third joint is short; the fourth reaches as far the thigh is oval, the metacarpus posteriorly dilated and distally produced behind; the wrist and hand subequal, straight, and the finger short and straight. The sixth pair closely resemble the fifth, except that the coxa is shorter, and the thigh is fringed with plumose hairs. The seventh pair of legs are more than twice the length of the preceding pair: the coxa is short, the thigh di- lated, the metacarpus long and narrow, longer than the thigh; the wrist is as long as the metacarpal joint; the hand is a little shorter and more narrow than the wrist, and internally fringed with cilia; the finger is nearly as long as the hand, straight, ciliated, and tapering to a sharp point. ‘The caudal appendages are long, reaching to nearly the same distance; their branches are generally free from hairs, and are styliform. The terminal plate is lanceolate, squamiform. This species is very free from colour, except the eye, which is of a deep purple, but, under the microscope, the animal appears to be rough on the surface, an ap- pearance due to a number of scale-like elevations of the skin. Under a power of about 300 diameters, the in- tegument of the body of the animal appears to be covered with minute distant scales; they gradually in- crease and thicken, until they assume their greatest degree of number and character upon the anterior segments of the tail, and then again gradually decrease in size and importance towards the posterior extremity of the ani- mal. The first specimen which we received was sent to us by Mr. Edward, of Banff, who took it in that locality. It has since been procured by Mr. Gregor, from the stomach of a haddock, taken from about thirty or forty fathoms, near the same place. 168 GAMMARIDA, AMPHIPODA. PHOXIDES. NATATORIA. MONOCULODES STIMPSONI. Specific character. Pleon not carinated; thighs of the sixth pair of legs not plumigeous. Length, $, inch. Monoculodes Stimpsoni. Spence Barr, Cat. Amph. Crust. Brit. Mus. p. 105, pl. xvii. fig. 3. Tue back of the animal has no perceptible carina. The head is advanced and depressed, but scarcely so much curved as in M. carinatus. The eye is undefined, and situated above, and rather in advance of, the point where the antenne articulate with the head. The su- perior antenne reach rather beyond the peduncle of the inferior; the first joint of the peduncle extends as far as the extremity of the head; the second joint is rather more than half the length of the first, and much slighter; the third joint is small, being scarcely a third the length of the second; the flagellum is slender, and scarcely the length of the peduncle. The inferior pair of antenne are one-third longer than the superior, and reach as far as the seventh segment of the body; the first two joints are covered by the coxe of the first pair MONOCULODES STIMPSONI. 169 as the extremity of the peduncle of the superior ; the fifth is but little longer than the fourth, and reaches nearly to the extremity of the flagellum of the superior pair ; the flagellum is about the length of the last joint of the peduncle, having the first articulus equal to five of the succeeding, which are subequally short, and scarcely longer than broad. The first pair of legs are moderately large, larger in proportion to the second pair than in M. carinatus ; the wrist is inferiorly produced to a broad plate, reaching nearly to the extremity of the inferior margin, and having its edge fringed with fine hairs; the hand is longer than the wrist; the superior margin forms, with that of the wrist, one continuous arcuate line; the inferior margin lies subparallel with the upper, but the hand is narrower near the wrist than towards the palm ; the palm is convex, armed with two or three rows of short posteriorly-curved hooks, and is defined by a strong spine ; the finger is about the length of the palm, arcuate, and sharply pointed. The second pair of legs have the wrist produced along the inferior margin of the hand to the extremity, where it meets and antagonizes with the apex of the finger; the hand is longer than that of the first pair of legs,—it is narrow near the wrist, and becomes still narrower at the distal extremity, where there is a scarcely-perceptible oblique palm; the finger is short, and only very slightly curved. The third and fourth pairs of legs have the hand widening towards the distal extremity, the dilated portion taking place anterior to the point where the finger articulates with the hand, and furnished with a copious brush of hair at the extre- mity: the fingers are quite rudimentary. The fourth and fifth pairs of legs resemble each other very closely ; their coxz are shorter than those of the anterior pairs of legs; their second joints are less enlarged than is 170 GAMMARIDA. common in the order; the fourth joints are dilated pos- teriorly, and distally produced to a point—these and the two following joints are fringed with small hairs; the fingers are straight and posteriorly directed. The seventh or last pair of legs are very long, three or four times as long as the others; the coxa is quite as deep as that of the preceding legs; the second joint is about half as long as the preceding legs, considerably dilated, and the posterior margins fringed with hair; the third joint is short, the three following are subequally long and nar- row ; the finger is as long as the hand, short, straight, styliform, and anteriorly directed. The posterior pair of caudal appendages are not longer than the preceding, and have the branches longer than the peduncle. The central tail-piete is nearly as long as the peduncle of the last pair of caudal appendages. We first took a mutilated specimen of this animal from some trawl-refuse, in the neighbourhood of Plymouth ; it was from this imperfect animal that the original de- scription, in the Catalogue of the British Museum, was made. The Rev. A. M. Norman has subsequently al- lowed us to examine a specimen which he procured on the coast of Northumberland. We have dedicated this species to our valued correspondent, Mr. Stimpson, the zoologist of the United States’ Expedition to Japan, by whom the genus was established upon animals procured off the coast of the United States, and to whom we are indebted for many named species of his crustaceous dis- coveries. KROYERA. aa AMPHIPODA. PHOXIDES., NATATORIA. Genus—KROYERA. Kroyera. Sprncr Bats, Cat. Amph. Brit. Mus. p. 106, but not of Synopsis Brit. Amph. Ann. Nat. Hist., 2 ser. xix. p. 140, Feb. 1857. Generic character. Like Monoculodes, but having the eyes apart, and the second pair of gnathopoda chelate. TuE head is produced and anteriorly depressed. The eyes are apart and distinct. The superior pair of an- tennz are without a secondary appendage. The in- ferior are slightly longer than the superior. The first pair of legs have the hands tolerably robust; the wrist anteriorly produced along the inferior margin of the hand, until the tip reaches the lower edge of the palm. The second pair are longer than the first, and have the anterior extremity of the wrist produced along and ex- tending beyond the inferior margin of the hand; the hand has the inferior angle produced anteriorly, so as to form, with the impinging finger, a perfectly didactyle claw. The third and fourth pairs of legs are uniform and subequal. ‘The fifth and sixth pairs are uniform and subequal, being robust, and scarcely longer than the preceding pair. The seventh pair are very long, and terminate in a straight styliform finger. The caudal ap- pendages are double-branched, and the central tail-plate is squamiform and single. The species on which this genus was founded was first described as belonging to the same genus as Monocu- lodes, and under the name of Kroyera. But on dis- 172 GAMMARIDA., covering that Stimpson’s genus Monoculodes was evi- dently the same as part of the genus Kroyera, Stimp- son’s name was adopted for those species which evidently belonged to that genus; whilst that of Mroyera has been given to the following species, which could not be retained in it. Since the above description has been in type, we have obtained an animal which coincides with the present genus in all its conditions, except that the eyes coalesce into a single organ, as in Monoculodes. We think it more convenient for the present to retain both in this genus until future observation shall enable us to determine the relative importance of this distinction. The vignette represents a naval engagement when Eng- land put faith in her wooden walls. KROYERA ARENARIA, 173 AMPHIPODA., PHOXIDES. NATATORIA. XN KROYERA ARENARIA. Specific character. Eyes small, round. Antenne subequal. First pair of gnathopoda as in Monoculodes. Second pair having the propodos long and narrow ; the distal extremity of the carpus inferiorly produced beyond the apex of the dactylos, Posterior pair of pleopoda not so long as the preced- ing. ‘Telson entire, dorsally concave. Length, 3 inch. Kroyera arenaria. Spence Barn, Tyneside Field Nat. Club, vol. iv. pt. 1. p. 15, pl. ii. fig. 1. Cat. Amph. Brit. Mus. p. 106, pl. xvii. fig. 4. Tue body is smooth, and the head considerably pro- duced and anteriorly depressed. The eyes are of mode- rate size, round, white, and placed behind the superior antenne. ‘The superior pair of antennz reach to the fourth segment of the body, and have the first joint of the peduncle longer than the other two, which are short, and scarcely larger than the first articulus of the flagel- lum, which is about twice the length of the peduncle, and consists of about twelve or fourteen articuli. The inferior pair of antennz reach one-fourth further than 174 GAMMARIDA. the superior pair, and have the peduncle more conspi- cuous than that of the superior; only three joints of the peduncle are visible beyond the projecting lateral wall of the head,—these are subequal, and reach a little beyond the extremity of the peduncle of the superior pair; and the flagellum is scarcely longer than the peduncle. The coxe are not very deep; and the first pair of legs have the hand oval, with the palm oblique ; the tip of the infero-anterior process of the wrist ex- tends a little beyond the inferior angle of the hand, and forms a point, against which the apex of the finger impinges, where it closes on the palm. ‘The second pair of legs are longer than the first, and have the hand less robust,—it is long and slender, the margins being pa- rallel, and the inferior angle produced anteriorly in a straight line, terminating in a sharply-pointed curve ; the finger is narrow, sharp, and slightly curved, lying in a line continuous with the hand, and impinging against the inferior process, or thumb, only near the apex, or where the margins meet; the tips of the finger and thumb then cross each other. The wrist is short and narrow, and the anterior extremity is inferiorly produced into a long narrow process, that reaches beyond the apex of the claw, where it is slightly dilated or lobed, and tipped with a few hairs. The two next pair of legs are similar, and of the same length,—they are longer and a little stouter than the second, with the hands dilated anteriorly, similar to those in Westwoodilla and Monoculodes, and having the anterior distal extremity covered with a thick brush of hair; the fingers are short, strong, and directed backwards. The two succeeding pairs of legs are also similar to each other: they have the thighs oval, the meta- carpal joints posteriorly dilated and inferiorly produced ; the wrists and hands of nearly the same length, and fringed KROYERA ARENARIA. 175 with hair; the fingers are short, stout, and directed for- wards. The last pair of legs are very long,* having the thigh oblong, the metacarpal joint posteriorly dilated and inferiorly produced, but not so largely as in the preceding pair; the hand is long and straight; and the finger is very long, straight, styliform. The caudal appendages are double-branched, the posterior pair hav- ing the peduncle much shorter than that of the others. The terminal plate is single, scale-like, dorsally cupped, and tipped with a few hairs. The first specimen which we received of this species was sent to us by Mr. Albany Hancock, who took it on the beach near Sunderland, near the spot given in the vignette (p. 176), which was kindly drawn for this work by Miss M. Hancock. This crustacean formed the subject of observation by Mr. Hancock, on account of the tracks which it makes in the sand, described in his “ Memoir on Vermiform Fossils,” read at the Meeting of the British Association at Leeds, September 22nd, 1858, and published in the ‘* Annals of Natural History,” ser. 3, vol. ii., as well as in the ‘ Transactions of the Tyneside Field Naturalists’ Club,” vol. iv. pt. 1, for 1858. Mr. Hancock says that the track of this species “ is in the form of a narrow wedge-shaped furrow, about two-tenths of an inch wide, with margins occasionally a little elevated. Its windings are very capricious, irregularly rounded, frequently abruptly angulated, and sometimes, for a considerable distance, finely and regu- larly zig-zagged. This species (of tract) is often * By an oversight, it has been figured with a joint too much, the hand being repeated ; the space, in fact, between the extremity of the metacarpus and the base of the finger, should have been divided into two, instead of three portions. 176 GAMMARID. found in close proximity to the broad form previ- ously described [made by Sulcator]; but occasionally it occurs high up on the beach, and in pools and small hollows between the ripple-ridges. In such situations, however, it is not confined to the bottoms of the hol- lows, but likewise passes up the sides of the bordering ridges.” We have also received a specimen from Mr. Robertson, of Glasgow, which was taken by him at Cumbrae, N. B. The vignette below is the sketch of Whitburn sands alluded to in the preceding page. KROYERA ALTAMARINA, 177 AMPHIPODA. PHOXIDES, NATATORLA. KROYERA ALTAMARINA. N.S. Specific character. Eyes confluent, and placed anterior to the superior antenne. Second pair of gnathopoda having the inferior angle of the carpus produced anteriorly, scarcely beyond the apex of the dactylos. Length } inch. Tur head is anteriorly produced and depressed; the segments of the body are shorter than the three anterior segments of the tail. The first two segments of the tail are somewhat elevated posteriorly, giving a slightly-im- bricated appearance to that portion of the back when viewed laterally. The eyes are fused into a single organ, as in Monoculodes. ‘The antennz are injured in the only known specimen, but the second joint of the superior antennz is much more slender than the first ; but in the inferior, the first three are equally stout, whilst the fourth is more slender, and as long as the two preceding. The first pair of legs do not differ from those of K. arenaria. ‘The second pair have the hand N 178 GAMMARIDA. similarly formed to that of K. arenaria, but the carpal process is not quite so long, and ends in an upturned point; the digital process of the hand is also curved at the apex, and terminates in two small dental processes ; the finger is long, slightly curved, and the apex reaches as far as the extremity of the carpal process, against which it appears to be able toimpinge. The next two pairs of legs resemble each other, differing from those of K. arenaria only in being furnished with more hairs, which extend on both margins to a considerable extent. The fifth pair of legs are wanting in our single speci- men, but we suppose them to resemble the seventh pair, and if so, the metacarpus is not quite so largely lobed as in K. arenaria. The seventh pair of legs have lost the distal joints, but those that remain indicate parts of a long limb. The caudal appendages have not been closely examined, but they appear to correspond very nearly with those of K. arenaria. It is only after much deliberation that we have de- termined to embrace this monocular form in the same genus with a binocular species. ‘The very close resem- blance in the general detail of the two animals induces us to consider that the variation in the organs of vision may be sexual, or dependent upon certain altered physical conditions. We have little doubt but that, like its near ally A. arenaria, this species is a burrower; but whilst the habitat of the former is on the sea-beach, where the light is strong, that of the latter is under a pressure of from seventy to ninety fathoms of water, where the light can scarcely penetrate, even should the creature not plough its way beneath the soil. The specimen from which this description and figure are taken is in the collection of the Rev. A. M. Norman, who dredged it sixty miles east of Shetland. AMPHILOCHUS. 179 AMPHIPODA. PHOXIDES., NATATORLA. Genus—AMPHILOCHUS. Amphilochus. Svunce Barr, Cat. Amph. Brit. Mus. p. 107. Generic character. Cephalon anteriorly produced. yes two. Superior antennze without a secondary appendage. Gnathopoda subchelate, each having the carpus infero-anteriorly produced. THE head in this genus is produced considerably in advance, and curved downwards. ‘The eyes are two dis- tinct organs, and are situated in their normal position, between the superior and inferior antenne. The su- perior antennz are tolerably robust, somewhat longer than the inferior pair, and not furnished with a secondary appendage. The inferior antennz are more slender than the superior. The arms are furnished with subchelate hands, but those of the second pair are larger than those of the first pair: both are, however, remarkable for the extension of the infero-anterior angle of the wrist. In this they approximate to the genus Monoculodes, but the form of the eyes appears to warrant their generic separa- tion. The recent discovery, however, of a species of Kroyera, which differs from the type of the genus in little else than in the character of these organs, induces us to believe it possible that future research in this branch of natural history may establish a closer alliance between Amphilochus and Monoculodes. 180 GAMMARID. AMPHIPODA. PHOXIDES. NATATORIA. AMPHILOCHUS MANUDENS. Specific character. Second pair of gnathopoda having the propodos tri- angular ; the superior distal angle being produced beyond the articulation of the dactylos. Middle joints of the flagellum of the superior autenne fur- nished beneath with elongated hairs, Length, 3 inch. Amphilochus manudens. Spunck Barr, Cat. Amph. Crust. Brit, Mus, p- 107, pl. xvii. fig. 6. Tue head is anteriorly produced and depressed, but not incurved. The segments of the body are not more than half the length of those of the anterior half of the tail. The eyes are round, and not very large. The superior antennz are longer than the inferior; the fla- gellum is not so long as the peduncle. The inferior antenne are more slender than the superior, but the peduncle reaches almost as far as that of the superior ; the flagellum is scarcely longer than the last joint of the peduncle. The first pair of legs are rather small, and the infero-distal extremity of the wrist scarcely reaches to half the length of the hand; the hand is long and narrow, the palm, fringed with small hairs, extends the entire length of the joint, and is subparallel with the upper margin, which is produced beyond the point where the finger articulates with the hand; the finger is long AMPHILOCHUS MANUDENS. 151 and slender, more than usually bent, and reaches so far that, when closed, it impinges against and antagonizes with the produced extremity of the wrist, thus forming acomplex hand. ‘The second pair of legs are longer and stouter than the preceding; the wrist has the antero- inferior angle more elongated; the hand is triangular, the lower margin gradually diverging from the upper, the upper being the longer, and extending, in a sharp tooth-like process, beyond the articulation between the hand and the finger; the palm is slightly convex, and somewhat crenulated ; the finger is sharp and curved, and the extremity reaches the ciliated apex of the produced wrist. The remaining appendages offer no material cha- racter. They are rather slender, and all nearly of the same length. ‘The middle caudal plate is lanceolate. This animal, of which we have only seen a single speci- men, was sent to us by our valued correspondent, Mr, David Robertson, of Glasgow, who states that he had seen a second individual. It was taken by him from the roots of Laminaria, in a few fathoms of water, at Cumbrae, Scotland. Its colour, when it reached us, was claret-red. 182 GAMMARID. AMPHIPODA. PHOXIDES. NATATORTIA. Genus—DARWINIA. Darwinia. Svence Bate, Brit. Assoc. Rep. 1855, p. 58. Ann. Nat. Hist. 1 ser. xix. 141, Feb. 1857. Cat. Crust. Amph. Brit. Mus. p. 108. Generic character. Cephalon produced anteriorly. Superior antenne without a secondary appendage. Gnathopoda smaller than the pereiopoda, subchelate. Pereiopoda subequal ; dactyla powerful. Posterior pair of pleopoda biramous. Telson single. Tue head of this genus is produced anteriorly to a point. ‘The body is arched, and the segments subequal. The third segment of the tail is remarkable for being not so deep as the preceding, a feature which exhibits an approximation to the character of Oxycephalus, and other genera among the Hyperina. The eyes are round, and situated at the lateral margins of the head, between the superior and inferior antenne. The superior antenne are subequal to the inferior, somewhat more robust, and not furnished with a secondary appendage. ‘The first two pairs of legs are small, and imperfectly subchelate, the second being a little larger than the first, but neither of them is as large as the true walking legs, all of which are about the same length, rather short, but very robust and strong, each terminating in a long, stout, slightly- curved, sharp finger. The caudal appendages are bi- ramous, and the terminal piece consists of a single plate. This genus bears a close resemblance to Kroyer’s de- DARWINIA. 183 scription of the genus Lafystius, (Tidskr. 1 ser. vol. iv. p- 156,) from which it differs chiefly in the form of the second pair of legs, which, in the latter genus, are de- scribed as having the finger sublaminar, with the apex somewhat setose, we presume, as in Callisoma. Their habits also appear to be similar. This genus is named in compliment to the distin- guished author of the ‘* Monograph on the Cirripedia,” one of the most complete works of the kind ever pub- lished. FRIGATE BEFORE THE WIND, SECOND-RATE AND FRIGATE GOING FRUE. 184 GAMMARIDA. AMPHIPODA. PHOXIDES. NAVATORIA, DARWINIA COMPRESSA. Specific character. Cephalon produced to an obtuse point. Fourth seg- ment of the pleon considerably narrower than the third. Superior antenne longer and stouter than the inferior. Length J, inch. Darwinia campressa. Spence Bare, Brit. Assoc. Rep. 1855, p. 58. Ann. Nat. Hist. 1 ser. xix. p. 141, Feb. 1857. Cat. Amph. Crust. Brit. Mus. p. 108, pl. xvii. fig. 7. Wuire, Hist. Brit. Crust. p. 176. Tue head is produced anteriorly to an obtuse point. The body is much distended, and increases in breadth to the third segment, whence it as gradually decreases pos- terlorly. The tail is narrow, with the third segment shorter than the preceding; the three last segments are extremely short, and generally lie folded, closely com- pressed, beneath the body of the animal, a circumstance which suggested the specific name. The eyes are round, and situated between the superior and inferior antenne. The superior antennz are about one-fourth the length of the animal, but longer and more robust than the inferior ; DARWINIA COMPRESSA. 185 the peduncle is not longer than the flagellum. The in- ferior antenne are scarcely longer than the peduncle of the superior. The first pair of legs are very small, and are generally so closely folded beneath the animal that they are with difficulty examined; the wrist and hand are subequally long, and very slight; the finger is long and slender, and capable of being shut upon the inferior margin of the hand. The second pair of legs are but a little larger than the first, and have the wrist longer than the hand; the hand is truncate, the palm being at nearly right angles with the inferior margin; the finger is long, and furnished with a single subapical tooth, giving it the appearance of a somewhat forked extremity. The walk- ing legs are very robust; the coxz gradually increase in depth from the first to the fourth, which is produced downwards to an obtuse point. All the walking legs are nearly equal in length and strength, and each terminates in a strong pointed hook-like finger, which Liljeborg not inaptly, in his description of Lafystius, compares to the claws of a feline mammal. They are long and powerful organs, and are indicative of parasitic habits. The three posterior pairs of caudal appendages reach to about the same length, and are very free from hairs. The tail-piece is lanceolate in its form. This species was first taken by Mr. Edward, of Banff, at the entrance of the Moray Frith, whence also we have received specimens from Mr. Gregor, of Macduff. Mr. Loughrin has also sent us specimens from Polperro. These last were as white as writing-paper, and in this respect differed from those received from the Moray Frith, which were of a brown hue. After being kept a short time, the Cornish individuals assumed the colour of the North British specimens, hence we may assume white to be the 186 GAMMARIDA. natural colour. Mr. Loughrin says, that his specimens were procured either from the throat of a cod-fish, or from the skin of the common dogfish (Squalus acanthias), The natatory legs of these specimens were thickly covered with a species of Vorticella, a circumstance which would suggest that they were animals of sluggish or quiet habits, rather than living on the surface of the fast-swimming dog- fish ; whilst their peculiar colour would induce the be- lief that they inhabited a sheltered and dark position, such as that of the throat of the codfish rather than the free ocean. The vignette represents a group of the Infusoria which infest this ‘amphipod. SULCATOR. 187 AMPHIPODA. PHOXIDES. NATATORIA Genus—SULCA TOR. Sulcator. Spence Bate, Ann. Nat. Hist. vol. xiii. p. 504, 1854; xix. p. 140. Rep. Brit. Assoc. 1855, p. 58. Cat. Amph. Brit. Mus. p. 112. Warts, Hist. Brit. Crust. p. 174. Gossx, Marine Zool. p. 142. Bellia. Spencr Barr, Ann. Nat. Hist. vol. vii. p. 318, 1851. Generic character. Cephalon anteriorly produced. Gnatho- poda small, imperfectly subchelate. Pereiopoda having the dactyla obsolete, most of the joints squamously developed. THE head is developed anteriorly, and produced cen- trally to a point. The body of the animal is much distended, the centre, however, not being materially wider than the other portions. The third segment of the tail is remarkably long, and has the lateral walls considerably developed, so that the three posterior seg- ments of the tail, together with their appendages, lie folded within it, seldom appearing extended. The eyes are small. The superior antenne are fur- nished with a secondary appendage. The coxe are large. The arms are feeble and imperfectly subche- late. The walking legs have all the joints developed in the form of large plate-like scales, except the fingers, which are represented by a few stout spines. The last pair of caudal appendages are double-branched, and the central tail-piece is single, but cleft. This genus bears a near resemblance to that described by Say, under the name of Lepidactylis, in the ‘ Pro- ceedings of the Academy of Philadelphia,” vol. i. p. 2. 188 GAMMARID. It may be that they are synonymous, but the very im- perfect manner in which Say’s genus is described, arising from the want of fixed homological names for the several parts of the animal, precludes us from expressing more than a supposition of their identity. The habits of the only species of Sulcator appear to differ from those of the only species of Lepidactylis de- scribed, inasmuch as the former is very sluggish, and a burrower, whereas the latter is stated by Say to be very active, much resembling in its movements the water- beetles of the genus Dytiscus. The accompanying vignette represents one of our fa- vourite hunting-grounds, the Tor Rock in Oxwich Bay, near which our specimens of this genus were taken. SULCATOR ARENARIUS, 189 AMPHIPODA. NATATORIA., PHOXIDES. SULCATOR ARENARIUS. Sand Furrow-maker. Specific character. Body not compressed, three posterior segments of the pleon bent under and enclosed beneath the third. Antenne subequal. Coxe of the pereiopoda largely developed. Basal joint of the three posterior pairs also largely developed ; dactyla wanting, or only represented by stiff spines. Length, 31 inch (not including the inflected portion of the pleon). Sulcator arenarius. Spuncn Bars, Ann. Nat. Hist. vol. xiii. p. 504 (1854) vol. xix. p. 140, 1857. Rep. Brit. Assoc. 1855, p. 58. Trans. Tyneside Nat. Field Club, vol. iv. p. 15, pl. ii. fig. 2, 1858. Cat. Amph. Brit. Mus. p. 112, pl. xviii. Gossz, Marine Zool. p. 142, f. 264. Wuire, Hist. Brit. Crust. p. 174. Bellia arenaria. Sprnce Batsr, Ann. Nat. Hist. vol. vii. p. 318, 1851. Dana, United States’ Explor. Exped. Crust. p. 912. THE upper portion of the head is projected anteriorly as a flat hood, but has an excavation on each side, cor- responding to the superior pair of antenne, while the centre terminates in a blunt point. Between the antennz the integument also extends into a point, though not so 190 GAMMARID&. far advanced as the central one. The body is smooth, and not compressed. The third segment of the tail is very long, and the three posterior segments are inflected and inclosed beneath it. The eyes are small and round, and the su- perior antenne are short,—about as long again as the head ; the secondary appendage is nearly as long as the flagellum. ‘The inferior antenne are a little longer than the superior. The first two pairs of legs are small, slender, and feeble, scarcely subchelate, the fingers being almost rudimentary. All the others are more robust, and have the fingers wanting, being replaced by two or three stout spines. The second and third pairs have the wrists short, but as broad again as long, and the hands increase in breadth from the articulation to the distal extremity, somewhat in the shape of a pear. The hand is capable of being impinged against the wrist, thus forming an imperfect prehensile organ. The next three pairs have most of the joints broadly developed, and lie folded against the sides of the animal, somewhat resem- bling scale armour. The swimming legs are short, and the three caudal appendages are short and spinous. The terminal plate is single, but deeply divided, and each half is dilated so as to overlap the other. The animal is not very hairy, but the hairs it possesses are of very diversi- fied forms, some simple, others toothed in a variety of ways, both in single and double rows, while others are plumose and ciliated. This singular creature lives on the coast, on sandy shores, between the tide-marks, coming to the surface when the tide is in, and again burrowing beneath it when the ebbing waters leave the sand dry. We have observed that they generally make a furrow in the sand, about a foot long, at the extremity of which we took them about an inch beneath the surface. SULCATOR ARENARIUS. 191 Mr. Albany Hancock has paid considerable attention to the furrows made by this creature, and described them in a paper entitled ‘On certain Vermiform Fossils in the Mountain Limestone Districts of the North of Eng- land,” published in the “ Transactions of the Tyne-side Naturalist’s Field Club,’ which was read at the British Association at Leeds in 1858. The animal appears to be a very sluggish creature, since Infusoria attach themselves to the hairs of the na- tatory appendages. In colour the animal resembles the sand in which it lives, and may readily be passed without recognition. Mr. Gordon states that the eyes were cream-coloured in the specimen which he found. We believe, on the con- trary, that those which we took on the coast of Glamor- gan had dark, if not black, eyes. Specimens of this species in the British Museum were taken in the neighbourhood of Falmouth by Dr. Leach. It has been sent to us from the Moray Frith, having been picked up at Lossiemouth, on the sand from which the tide had just receded, by the Rev. Geo. Gordon ; also from the coast of Northumberland, where it was found by Mr. Albany Hancock. The specimen from which our figure was taken we took, in company with Mr. Matthew Moggridge and Mr. J. Gwyn Jeffreys, in Oxwich Bay, and we have also found it in Rhosilly Bay in Glamorgan. 192 GAMMARIDA. AMPHIPODA. PHOXTDES. NATATORIA. UROTHOE. Urothoe. Dana, United States’ Explor. Exped. p. 920. Spence Bars, Cat. Amph. Brit. Mus. p. 114. Generic character. Body scarcely compressed. Eyes two. Superior antenne having a secondary appendage. Gnathopoda subequal, subchelate. Pereiopoda having the dactyla constant. Posterior pair of pleopoda biramous. Telson double. Some of the species of this genus bear a resemblance to Sulcator. The body is but slightly, if at ail, com- pressed. They have two eyes, which are always small and round. The superior antennz have a secondary appendage. The coxe are very large and deep; the fifth pair being smaller than the preceding. The first two pairs of legs are subchelate, and are furnished with well-developed fingers, as are all the other legs—a cha- racter sufficiently important to separate the species of this genus from that of Sulcator. The posterior pair of caudal appendages are two-branched, the branches being very long and foliaceous. The terminal plate is double. UROTHOE BAIRDII. 193 AMPHIPODA. PHOXIDES. NATATORIA. UROTHOE BAIRDII,. Specific character. Inferior pair of antenne nearly half the length of the body, having the flagellum three times as long as the peduncle. Inner branch of the terminal caudal appendages naked, Length 34 inch. Urothoe Bairdit. Sprunce Barn, Cat. Brit. Mus. p. 114, pl. xix. fig. 1. Tue head is not anteriorly produced. The eyes are round and small. The superior pair of antenne are about as long again as the head; the peduncle is about the same length as the flagellum; and the secondary ap- pendage is about half as long as the flagellum. The inferior antenne have the peduncle not reaching beyond the extremity of the peduncle of the superior, and furnished with a few small spines and long hairs: the flagellum is about three times as long as the peduncle; the articuli nearer to the peduncle are not longer than they are broad, whilst those towards the extremity gra- dually increase in length. The first two pairs of legs are uniform, the anterior pair being a little the larger ; O 194 GAMMARIDA. the hands gradually increase in their diameter towards the palm, which occupies the anterior margin: it is con- vex, but its limit is not defined, but gradually rounded into the inferior margin, and_ slightly fringed with hairs. The third and fourth pairs of legs are also uni- form, and furnished along the posterior margins of the wrists and hands with strong stiff spines, which appear to have the capability of being brought into contact with each other, and so of obtaining a prehensile power. The next pair of legs have the thigh gradually dilated, and the posterior margin of the succeeding joints furnished with long plumose hairs, and the anterior margin with fasciculi of spines: they terminate in a knife- shaped finger, the anterior margin of which is entire. The last two pairs of legs are uniform; they are fur- nished with a few short hairs and spines, and terminate in a straight finger. The antepenultimate pair of caudal appendages have the branches very unequal, whilst those of the penultimate are equal, as are also those of the ultimate, which are much longer, and have the inner branch covered with plumose hairs, whilst the outer one is clean, and tipped with a short spine at the extremity. The terminal plate or tail-piece is double, each division being tipped with a small central spine, flanked on each side with a minute hair. We received this species from our kind correspondent, Mr. Gregor, of Macduff, who took it in the Moray Frith. It is named in compliment to the indefatigable author of the ‘‘ History of the British Entomostraca.” UROTHOE MARINUS. 195 AMPHIPODA. PHOXIDES. NATATORIA. UROTHOE MARINUS. Specific character. Superior antenne longer than the inferior. Inferior antenne haying the flagellum uniarticulate. Second pair of gnathopoda with the palm slightly oblique. Both branches of the terminal caudal ap- pendages plumose. Length 33 inch. Urothoe marinus. Spence Bare, Cat. Amph. Brit. Mus. p. 145, pl. xix. fig. 2. Suleator marinus, Sprence Bats, Synop. Brit. Amph. Ann. Nat. Hist. ser. 2, xix. p. 140, Feb. 1857. Whuirn, Hist. Brit. Crust. polio: Tus species bears a close resemblance to the preceding in its general aspect, but may readily be detected from it by the shortness of the inferior antenne. The superior antenna are about one-fourth of the length of the animal, and have a flagellum scarcely longer than the last joint of the peduncle. The inferior antennz scarcely reach beyond the extremity of the peduncle of the superior. The first joint of the peduncle is surmounted by three longitudinal rows of spines, each 02 196 GAMMARID&. spine successively increasing in length to the distal ex- tremity of the joint; the flagellum consists of but a single articulus tipped with two long hairs. The first pair of legs are smaller than the second; the wrist is longer than the hand, and is inferiorly produced ante- riorly, but not to any very great extent; the hand is narrow, but slightly increasing in diameter anteriorly ; the palm is not defined, and the finger is long and curved. The second pair of legs are larger than the first, but differ not in any very great extent of form; the wrist has the inferior margin more decidedly convex, and is fringed with two rows of hairs equidistantly apart ; in one row the cilia are directed anteriorly, and in the other they are directed posteriorly, and the distal margin is excavated; the hand increases in breadth anteriorly ; the palm is slightly concave, but its limit is imperfectly defined, the inferior angle being rounded off, and fur- nished with a fasciculus of hairs. The third and fourth pairs of legs resemble each other; they are chiefly pe- culiar for having the wrist and the hand posteriorly furnished with strong blunt spines; those that are placed nearest to the distal extremity are the longest in each joint, and are nearly as long and powerful as the finger. The hand appears to have the power of being able to be pressed back against the wrist, and the pressure of the spines between each other gives the organ an imperfect but strong prehensile power. In the fifth pair of legs the dilated thigh is of a square form, rather broader than long, and the posterior margin being crenulated, and fringed with a row of simple hairs. The rest of the leg is remarkable for long plumose cilia, which ornament the posterior margin, while the anterior is furnished with fasciculi of short strong spines; the finger is not curved, but has the anterior margin a UROTHOE MARINUS. 197 little dilated, and minutely serrated along the distal half. The seventh pair of legs have the thigh rounded; the rest of the joints posteriorly not furnished with hairs, but the anterior margin is armed with a few stout spines; the finger is crooked, and furnished with three bead-like tubercles on the anterior margin. The antepenultimate pair of caudal appendages have the branches very short, unequal in length, and styliform. The penultimate pair have the branches short, subequal, styliform, and free from hairs. The ultimate pair have the branches long, subequal, and plentifully furnished with plumose hairs. The central tail-piece has the approximate margin of each division nearly straight, and the external convex, and tipped with a few cilia and one stout spine. We have received this species from the Moray Frith, where it was procured by Mr. Gregor, of Macduff, from the stomach of a haddock captured in about thirty fathoms of water: also from Mr. Edward, of Banff, and the Rev. Geo. Gordon, of Elgin. It has also been sent to us from Cumbrae, where it was taken by Mr. D. Robertson ; and our lamented friend, the late Mr. Barlee, dredged it off the Shetlands. 198 GAMMARIDZ. AMPHIPODA. PHOXIDES. NATATORLA. UROTHOE BREVICORNIS. Specific character. Inferior antennz not longer than the peduncle of the superior, and not furnished with spines on the superior margin. Branches of the terminal caudal appendages not hirsute. Length 2, inch. Urothoe brevicornis. Srrence Bats, Cat. Amph. Crust. Brit. Mus. p. 116, TE som, tits Ile Tuis animal bears so close a resemblance to Urothoe marinus, that since it was originally described, we have much doubted whether it had not better have been described as a variety only. It may be that the dis- tinctions are those of sex, but the habitats as yet re- corded are very widely apart. The antenne are very similar to those in U. marinus, but the inferior are rather shorter, and are not furnished with those strong spines on the superior margin of the first joint of the peduncle, which form so remarkable a UROTHOE BREVICORNIS. 199 feature in U. marinus. The hands of the first two pairs of legs are rather more slender, and have not the antero- inferior margin of the wrist anteriorly produced, and the hands have the palms more oblique, and still more imperfectly defined. The third and fourth pairs of legs, although armed with spines, are not so strong as those of U. marinus. ‘The dilated thigh of the fifth pair of legs is almost triangular, and has not the pos- terior margin crenulated; the plumose hairs adorning the posterior margin are reduced to a single tuft on the carpus; the finger is very long, and has the anterior margin entire, or imperfectly serrated. The last two pairs are nearly uniform, and have the posterior margins of the thighs imperfectly crenulated, and the fingers are straight and styliform. The caudal appendages differ from those of U. marinus in the greater length of the base, and in the branches of the antepenultimate pair reaching beyond those of the penultimate. The branches of the ultimate are also shorter, and not fringed with hairs. ‘The middle tail-piece is long, naked, and obtuse. This species was sent to us by our kind friend, Mr. M. Webster, from Tenby, where he took it with the dredge. 200 GAMMARIDA. AMPHIPODA. PHOXIDES NATATORIA UROTHOE ELEGANS. Specific character. Inferior antenne nearly as long as the animal. 3ranches of the terminal caudal appendages very long and setose. Length 54 inch. Gammarus elegans. Sprrnce Bate, Rep. Brit. Assoc, 1855. Urothoe elegans. Spence Bare, Synop. &c. Ann. Nat. Hist. 2 ser. xix. p. 145, 1857. Cat. Amph. Brit. Mus. p. 117, pl. xx. fig. 2. Wurtz, Pop. Hist. Brit. Crust. p. 186. Tus species much resembles U. marinus, but differs from it in the following important points :—the eyes are uniform; the superior antennz are scarcely longer than the peduncle of the inferior; the flagellum of the inferior is very slender and long, being nearly as long as the animal. The rest of the animal scarcely offers any specific variation from U. marinus. Its colour is whitish buff, the anterior portion of the body being covered with small black dots, and the head, posterior coxee, and bases of the hind legs, as well as the sides of the terminal seg- ments of the body, beautifully mottled with pink. The first specimen was taken from some trawl refuse, brought in from the neighbourhood of the Eddystone Lighthouse. Its extremely beautiful colouring struck us with delight, and suggested its specific name, more particularly if it should prove constant. A second spe- UROTHOE ELEGANS. 201 cimen has been taken by Professor Kinahan, in Dublin Bay; and a third has been procured by the Rev. A. M. Norman and Mr. J. Gwyn Jeffreys, in from sixty to seventy fathoms, near the Outer Haaf Fishing Ground, off the Shetland Islands, This species is very closely allied to U. irrostratus, which was taken by Dana in the Zooloo Sea. Nor is this the only instance in which we have observed a very near affinity between the Crustacea of our own seas and those of the antipodal regions. 202 GAMMARID&, AMPHIPODA. PHOXIDES., NATATORLA. Genus—LILJEBORGIA. Liljeborgia. Sprence Bate, Cat. Amph. Crust. Brit. Mus. p 118. Generic character. Cephalon but slightly produced ante- riorly. Superior antenne furnished with a secondary appen- dage. Gnathopoda large, subchelate, second larger than the first, inferior carpal angle anteriorly produced. Posterior pair of pleopoda biramous. ‘Telson cleft. TuE head is not anteriorly produced to half the length of the first joint of the superior antenne. The seg- ments of the body are nearly as long* as those of the tail. The eyes are large. The superior antenne shorter than the inferior, and furnished with a secondary ap- pendage. The first two pairs of legs have the hands largely developed, the second being the larger, and the inferior angle of the wrist is produced to a short dis- tance along the inferior margin of the hand. The other legs are tolerably free from hairs, and have the fingers very straight. The last pair of caudal appendages have two branches, and the central tail-piece consists of a single plate, which is cleft at its apex. This genus is named in compliment to the distin- guished zoologist of the University of Upsala, Professor Liljeborg. * The length of a segment is measured in the same direction as that of the body of the animal; the breadth is when it is measured from side to side. LILJEBORGIA PALLIDA. 903 AMPHIPODA. PHOXIDES. NATATORIA. LILJEBORGIA PALLIDA. Specific character. Inferior antenne having the flagellum shorter than the last joint of the peduncle. Gnathopoda having the propoda ovate ; dactyla internally serrated. Posterior pair of pleopoda with the rami shorter than the peduncle. Length #, inch. Gammarus ? pallidus. Sprence Bats, Rep. Brit. Assoc. 1855, p.55. Synop. in Ann. Nat. Hist. 2 ser. xix. p. 145, 1857. Wuirtr, Pop. Hist. Brit. Crust. p. 185. Liljeborgia pallida. Spence Barter, Cat. Amph. Crust. Brit. Mus. p. 118. pl. xx. fig. 5. Gammarus brevicornis. Bruzeiius, Scand. Amph. Gam. p. 62, pl. iii. fig. 11. Tue first, second, and fourth segments of the tail are furnished with a small dorsal tooth. The posterior mar- gin of the third segment has a very distinct emargination just above the infero-posterior angle, which is formed into a small but distinct tooth. The eyes are large, 204. GAMMARIDA. tolerably round, and black. The superior antenne are about half as long again as the head; the peduncle is just the same length as the flagellum, but the first joint is longer than the other two; the flagellum is about half the length of the peduncle. The inferior antenne have the peduncle quite as long as the superior antennz, the last two joints being nearly of the same length, and about three times the length of the preceding. The first two pairs of legs are similarly formed, but differ con- siderably in size, the second having the hand more than twice as large again as that of the first; the wrist is in- feriorly produced along the inferior margin of the hand; the hand is ovate, the palm occupying nearly the entire length of the inferior margin, without its extent being properly defined, the edge is furnished with a smooth margin, fringed laterally with two sets of hairs, the one directed anteriorly, with the tip suddenly directed posteriorly into a hook; the other, consisting of alter- nate long and short hairs, directed backward, each being furnished on the anterior margin with two small cilia; the finger is curved, and armed on the inner margin with a deeply-serrated edge. The next two pairs of legs are more slender, and shorter than any of the others. The last three have the thighs very oval, and the fingers very long, straight, and styliform. The penultimate pair of caudal appendages are shorter than those that precede or follow it. The last pair have the branches much shorter than the peduncle. The tail- piece is oval, and subapically furnished with two simple hairs. This animal was first taken by us, in company with our valued friend Mr. T. P. Smyth, to whom we wish to express our obligation for having frequently placed his yacht at our disposal for dredging purposes. We LILJEBORGIA PALLIDA. 205 took several specimens on the eastern side of Drake’s Island. In the living animal the colour is very white, the back being stained with a rich crimson blotch, a circum- stance that enabled us to identify every specimen at once, The hands possess a rosy hue, and a tinge of the same colour may be detected on many of the articulations of the legs. Bruzelius, in his ** Memoir on the Amphipoda of Skan- dinavia,” has given the figure and description of a species of this genus, under the name of Gammarus brevicornis, which we consider to be identical with this, the only distinction being the shortness of the last joint of the peduncle of the lower antennez, the greater relative length of the flagellum, and the less ornate character of the serrature of the fingers to the hands, the result probably of being examined with a less powerful lens. The specimens, described by Bruzelius, were taken on the western shores of Sweden. 206 GAMMARID#, AMPHIPODA. PHOXITDES. WATATORIA. LILJEBORGIA SHETLANDICA. N.S. Specific character, First and second segments of the pleon unarmed ; fourth and fifth segments dorsally produced posteriorly into a small tooth. Secondary appendage of the superior antenne very short. Inferior antenne having the flagellum longer than the last joint of the peduncle. Dactyla of the gnathopoda unarmed. Length 4 inch. Tue head is not produced anteriorly. The dorsal surface of the animal is smooth, except a small tooth- like process, developed from the centre of the posterior margins of the ante- and penultimate segments of the tail. The eyes are small, round, and situated in their normal position on a lobe between the superior and in- ferior antenne. The superior antennez have the second joint of the peduncle longer than the first, the third joint very small, the flagellum reaching beyond the ex- tremity of the penultimate joint of the peduncle of the inferior antennz, and the secondary appendage extremely short. The inferior antenne have the last two joints of the peduncle very long and subequal, and the flagellum is rather longer than the last joint of the peduncle. The first pair of legs have the hands not dilated, but rather tapering to the distal extremity, and the wrist is nearly as long as the hand. The second pair of legs have the LILJEBORGIA SHETLANDICA. 207 wrist short, and _ slightly produced inferiorly; the hands dilated, ovate, tapering from the base to the distal extremity, the palm being continuous with the in- ferior margin, and fringed with long hairs, a depression near the centre marking the extent to which the very short finger reaches. The finger of this and the preced- ing pair has the inner margin smooth. The two suc- ceeding pairs of legs are small; the last three have the thighs, which gradually narrow from the base to the distal extremity, posteriorly serrated. The last pair of caudal appendages are wanting in all the specimens that we have seen. The central tail-piece is very deeply cleft. Several specimens of this species have been taken by the Rev. A. M. Norman, in forty fathoms, near Whalsey Lighthouse, and in from two to five fathoms, in Outer Skerries Harbour, Shetland. 208 GAMMARIDA. AMPHIPODA. PHOXIDES., NATATORIA, Genus—PH AZDRA. Phedra, Srrnce Bate, Quarterly Journal of Geol. Soc. 1858, p. 137. Cat. Amph. Brit. Mus. p. 119. Generic character. Cephalon produced anteriorly. Seg- ments of the pereion short, of the pleon long. Superior an- tenn shorter than the inferior, furnished with a secondary appendage. Posterior pair of pleopoda considerably elongated, biramous. Telson simple or notched. Tue head is anteriorly produced, but not to so great an extent as in some of the preceding genera. ‘The segments of the body are remarkably short, whilst those of the anterior half of the tail are extremely long. The eyes of the type were not observed. The superior antenne are shorter than the inferior, and rather more robust ; they are furnished with a secondary appendage. The coxz of the legs are small. The last three pairs of caudal appendages are double-branched, the branches of each pair respectively being subequal, those of the last pair being considerably elongated. The central tail-piece is squamiform or notched. This genus is founded on imperfect specimens. PHADRA ANTIQUA. 209 AMPHIPODA. PHOXIDES. NATATORIA, PHEDRA ANTIQUA. Specific character. Third segment of the pleon having the posterior margin toothed and minutely serrated. Superior antennz furnished with a secondary appendage. Rami of the posterior pair of pleopoda equal. Telson lanceolate. Length st inch. Phedra antiqua. Srunce Bate, Quart. Journ. Geol. Soc. 1858, p. 137, pl. 6, fig. 8. Cat. Crust. Amph. Brit. Mus. p. 120, pl. 21, fig. 2. Tre head is anteriorly produced to a central point. The third segment of the tail has the inferior half of the posterior margin minutely serrated, the limits being bounded by a prominent tooth above and below. The superior antenne have the first joint of the peduncle broader and longer than the second, and the second more so than the third, whilst the third is scarcely longer, though broader, than the first articulus of the flagellum ; the secondary appendage consists of a single articulus, but the remainder may be broken away. The inferior antennee have the joints of the peduncle that remain in the specimen before us as stout as those of the first joint of the superior. The coxe of the first four pair of legs are deeper than those of the three posterior. The three posterior pairs of legs are subequal. The poste- P 210 GAMMARIDZ. rior pair of caudal appendages are half as long again as the preceding. The telson is long and lanceolate. The specimen from which this description is taken was communicated to us by the Rev. Geo. Gordon, who took it in the Moray Frith, and has been described in the article in the ‘‘ Quarterly Journal of the Geological So- ciety” above referred to, as the nearest approach, among recent, Crustacea, to a fossil species found by Mr. Kirkby in the magnesian limestone of Durham, and described by him in the same work for 1857 (page 214) under the name of Prosoponiscus problematicus, Schlotheim. The fossil species differs from the recent forms in this subfamily, in two circumstances. The eyes are promi- nent upon the surface, like those of some Jsopods, and the anterior and deeper segments of the tail decrease in depth posteriorly, a condition which belongs to some species among the Hyperiide ; thus exhibiting additional evidence that the relation between the Phoaides and Hyperiide is closer than that between the latter and the Gammarides. PHAEDRA KINAHANT. Dt AMPHIPODA. PHOXIDES. NATATORIA. PHZDRA KINAHANI. Specific description. Dorsum of the three posterior segments of the pereion, and five of the pleon, centrally produced posteriorly, the last three into prominent teeth ; sides of the third segment of the pleon simple. Tel- son notched. Length 3, inch. Phedra Kinahant. Spence Barn, Cat. Amph. Crust. Bit. Mus. p. 119, pla iy fies: TuE head is anteriorly produced into a point, curved downwards. The body has each segment posteriorly pro- duced in the middle, the projection scarcely forming a tooth until the fourth and fifth segments, in which it becomes more distinctly marked. ‘The tail has a similar tooth on the two anterior segments, and also upon the fourth and fifth, but none upon the third. The eyes areround. The superior antenne are scarcely shorter than the inferior ; je Os Be GAMMARID&. they are large at the base, the first joint is longer than the other two; the first two are produced anteriorly to a point upon the upper surface, and notched into a dis- tinct tooth upon the inferior: the flagellum is longer than the peduncle, and the secondary appendage is about half the length of the primary. The inferior antennz have the upper distal extremity of each joint produced into a tooth; the flagellum is not longer than the last joint of the peduncle, and consists of one long articulus, or, more probably, several are fused together, of which the upper margin alone shows any indication of the several joints. The first two pairs of legs are uniform, both in dimensions and shape; the wrist is anteriorly produced along the inferior margin of the hand; the hand is sub- triangular, tolerably large, having the palm oblique, de- fined by a strong spine situated at the apex of an obtuse angle ; the palm is likewise furnished with short hairs, similarly formed to those on the hand of Lileborgia pallida. The walking legs are subequal, the two first being rather the shortest; the thighs of all are remark- ably narrow. ‘The ante- and penultimate pairs of caudal appendages have the upper margin of the outer branch serrated, being also marked at regular distances by a strong tooth. The ultimate pair are considerably longer than the preceding; the branches are of equal length, having their upper margins very slightly serrated. The middle tail-piece is notched, but to what extent we have not been able to determine. This species was taken from a nullipore bank off the coast near Cumbrae, by Mr. David Robertson, who kindly sent it to us. It is not improbable that this species may belong to a separate genus from Ph. antiqua, but all the parts of the latter, as far as known, correspond very nearly to PHEDRA KINAHANI. 213 those of this species, except, perhaps, the middle scale of the tail. Possessing, however, only a single speci- men, which had been mounted for the microscope before we received it, we have not been able, from its position, to ascertain the precise form of this appendage. We assume it to be single, with a central cleft; but a small notch at the extremity of each division is very con- stantly associated with a double tail-piece, so that it is not impossible that this may be found to be the case in the species now under consideration. The colour of the animal, when received by us, was of a reddish yellow. The accompanying vignette represents a view of Ailsa Crag, from a sketch kindly lent to us by our friend Dr. Scott of Melby, Shetland. 914 GAMMARIDA. AMPHIPODA. PHOXIDES., NATATORIA, Genus—IS ALA. Tsea. Mttnn-Epwarps, Ann. Sci. Nat. t. xx. p. 380. Hist. des Crust. t. ili, p. 26. Spmnor Barz, Ann. Nat. Hist. 2 ser. xix. p. 142, 1857. Cat. Amph. Crust. Brit. Mus. p. 122. Warts, Pop. Hist. Brit. Crust. p. 179. Generic character. Superior antenne having a secondary appendage. Gnathopoda subchelate; second pair the larger. Pereiopoda subchelate. Posterior pair of pleopoda biramous. Telson cylindrical, single. In this genus .the cephalon is not much produced anteriorly, The eyes are two. The superior antennz are longer than the inferior, and furnished with a se- condary appendage. The arms are subchelate; the hand of the second pair is larger than that of the first ; all the legs are likewise subchelate, the distal extremity of the hands being broadly dilated on the side towards which the joints bend. The coxe of the four or five anterior pairs of legs are deep. The last pair of caudal appendages are double-branched, and the central tail- piece is round and solid, the alimentary canal probably opening at its posterior extremity. Dana has established a subfamily to receive this genus, together with Anisopus of Templeton, under the name of Iseane, based upon the subchelate condition of the walk- ing legs. We do not perceive any advantage to be de- rived from this arrangement, since Isea and Anisopus (which latter we consider to belong either to the genus Amphithoé or Sunamphithoé) cannot be embraced in the same subfamily; and it will be found that there are other species possessing a more or less perfectly marked sub- chelate condition of the walking legs, which cannot be associated with Isa. ISHA MONTAGUI. Alles AMPHIPODA. PHOXIDES. NATATORLIA. ISHA MONTAGUI. Specific character. Wyes reniform. Superior antenne one-half the length of the animal. Gnathopoda having the propoda ovate. Pereiopoda having the propoda with the distal extremity serrated. Length, 4, inch. Tsea Montagu. Mttne-Epwarps, Ann. Sci. Nat. t. xx. p. 380. Hist. des Crust. t. iii. p. 26, pl. xxix. fig. 11. Spence Bare, Rep. Brit. Assoc. 1855, p. 58. Synop. Ann. Nat. Hist. 2 ser. xix, p. 142, 1857. Cat. Amph. Crust. Brit. Mus. p. 122, pl. 22, fig. 1. Wurrr, Pop. Hist. Brit. Crust. p. 179. THE eyes are not large, but kidney-shaped, and of a bright-red colour, The superior antennz are nearly half the length of the animal, the flagellum being as long as the peduncle, and the secondary appendage having but three articuli. The inferior antenne are not quite so long as the superior, and have the peduncle longer than the flagellum: the olfactory organs in this species are well developed. The first pair of legs are rather small, and have the palm of the hand very ob- 216 GAMMARID2A. lique. In the second pair the hand is much larger, but of nearly the same form, with the palm very oblique, and defined by two small spines. The third and fourth pairs of walking legs are alike, and have the posterior distal extremity of the hand strongly serrated, as have likewise the three posterior pairs, but being reversed, the serration is upon the anterior distal extremity. The last pair of caudal appendages have the branches of the same length, and reach a little beyond the preceding. The central tail-piece appears more like a small seg- ment of the animal than is usual; it is cylindrical, and surmounted by a small spinule. This species was taken by Professor Milne-Edwards, off the island of Chausay, and named by him in honour of Colonel Montagu, the pioneer of British marine zoology. We have procured it from some refuse brought by the trawlers from the neighbourhood of the Eddy- stone. All our specimens were taken from the back and branchial chambers of Maia squinado ; they seemed, indeed, to exist among the thick stiff fur on the carapace of this spider-crab as if they were in their accustomed habitat, their prehensile legs being peculiarly adapted for holding themselves on that animal. IPHIMEDTA,. A 7 AMPHIPODA. PHOXIDES. NATATORIA. Genus—IPHIMEDIA. Tphimedia, RaruxKe, Beitr. zur Faun. Norwegens, Nov. Act. Leop. vol. xx. p. 89 (1843). Spence Barn, Ann. Nat. Hist. 2 ser. xix. p- 141, Feb. 1857. Cat. Crust. Amph. Brit. Mus, p. 123. Wuirr, Pop. Hist. Brit. Crust. p. 176 (not Zphimedia, Dana). Microcheles. Kroyer, Tidsk. Nat. sec. 2, vol. ii. p. 5. Generic character. Cephalon produced anteriorly. Pereion distended. Pleon compressed. Eyes two. Antenne simple. Third pair of siagonopoda not unguiculate. First pair of gna- thopoda feeble; second also feeble, imperfectly subchelate. Pereiopoda robust, having large and powerful dactyla. Pos- terior pair of pleopoda biramous. Telson single, squamous, emarginate. In this genus the head is produced anteriorly. The body is dorsally rounded and laterally distended, while the tail is very rapidly narrowed. It is furnished with a small eye upon each side of the head. The antennz are subequal, and without a secondary appendage; the organs attendant upon the mouth are considerably pro- jected forwards. The first pair of legs are feeble, and have the fingers rudimentary; the second are likewise feeble, but terminate in an imperfectly chelate organ. The coxz increase in depth to the fourth, which is produced inferiorly to a sharp point. The last three pairs of legs are tolerably strong, and terminate in powerful fingers. The last pair of caudal appendages are double-branched, and the telson is single, squami- form, and emarginate. Our description differs from that of Rathke in a 218 GAMMARIDA. small extent. He describes the second pair of gnatho- poda as terminating in a simple non-prehensile form, whilst he figures them as seen in our drawing; and the first he calls chelate, whilst in the two species which we have had the opportunity of examining the finger is almost obsolete. Dana has, in his valuable work on Crustacea, evidently confused this genus with Atylus of Leach, to which all his species, except perhaps J. nodosa, undoubtedly be- long. The following vignette represents the pier-head at Lynmouth, on the north coast of Devonshire. IPHIMEDIA OBESA. 219 AMPHIPODA. PHOXIDES. NATATORIA. IPHIMEDIA OBKESA. Specific character. Cephalon anteriorly produced, but not much depressed. Last segment of the pereion, and three first of the pleon, furnished on each side of the dorsal central line with a posteriorly-directed tooth. Length 3; inch. Iphimedia obesa. RatuHKeE, Beitr. zur Faun. Norwegens, Nov. Act. Leop. vol. xx. (1843), p. 89, pl. iii. fig. 1. Spence Bars, Ann. Nat. 2 ser. xix. p. 141, Feb. 1857. Cat. Amph. Crust. Brit. Mus. p. 123, pl. xxii. fig. 2. Wuire, Pop. Hist. Brit. Crust. p. 176, pl. x. fig. 6. Microcheles armata. Kroyer, Nat. Tidskr. sec. 2, vol. ii. p. 5. Tue head, which is anteriorly produced, has the long projection not curved downwards. The last segment of the body and the first three of the tail are severally furnished with two dorsal teeth, one being on each side of the central line; the posterior margin of the third segment of the tail has likewise a strong tooth near the centre, and another at the infero-posterior angle. The eyes are somewhat reniform, and red in colour. The antennz are subequal, and about one-fourth of the length of the animal. The first pair of legs are weak, and have the hand long, with the infero-distal extremiy 290 GAMMARIDA. produced, the finger being rudimentary. In the more robust second pair the wrist is as long as the hand, which is produced and somewhat dilated towards the inferior angle of the distal extremity; the finger is small, subapical, and impinges against the hand so as to form an imperfectly chelate organ. The coxa of the fourth pair of legs has the upper portion of the pos- terior margin excavated, to receive the anterior lobe of the fifth pair of legs. The coxe of the last two pairs of legs are produced infero-posteriorly to an angle ; the thigh of the last pair has the lower half of the posterior margin -deeply serrated. The last three pairs of caudal appendages are subequal in length, and ter- minate in equal styliform branches. The terminal plate is emarginate at the apex. The colour of the animal appears to vary, but we are inclined to believe that it deepens in hue as it increases inage. The colour at first is yellow, with a few scat- tered cells of black pigment; these increase in number and dimensions until the animal becomes quite black. It has been sent to us from Tenby, where it was dredged by Mr. W. Welsh; from the Moray Frith, where it was taken by Mr. Gregor; Mr. Barlee also took it in the Shetlands and Loch Fyne. In Belfast Bay it was dredged in twenty fathoms by Mr. Thomp- son; and we have dredged it on the north-west of Drake’s Island in Plymouth Sound. IPHIMEDIA EBLANA. 221 AMPHIPODA. PHOXIDES. NATATORIA. IPHIMEDIA EBLANA, Specific description. Cephalon anteriorly produced, and curved down- wards. Last segment of the pereion, and first three of the pleon, furnished with a tooth on each side of the central line. First three segments of the pleon armed with a strong central dorsal tooth. Length § inch. Iphimedia Eblanew, Sprxcs BatE, Dublin Nat. Hist. Rev. vol. iv. p. 229, pl. xvi. fig. 1 (1857). Proceed. Nat. Hist. Soc. Dublin, p. 28, pl. xvi. fig. 1 (1856-7). Ann. Nat. Hist. 2 ser. vol. xx. p. 525. Cat. Amph. Crust. Brit. Mus. p. 124, pl. xxii. fig. 3. Tue head in this species is very short, and has the anterior projection curved downwards and inflexed. The first and last segments of the body are longer than the intermediate. The last segment of the body and the first three of the tail have their posterior margins furnished with two latero-dorsal teeth similar to the preceding species, but the first three segments of the 222 GAMMARIDA. tail are armed with a central dorsal tooth, directed pos- teriorly. The eyes are kidney-shaped. The antenne are short, being scarcely one-sixth the length of the animal. The first pair of legs are slender and weak, with the finger obsolete. The second pair of legs are scarcely stouter than the first, and terminate in an im- perfectly chelate organ. ‘The walking legs are tolerably robust, and differ from those of J. obesa only in having the thighs of the last three pairs produced posteriorly in two sharp points or teeth. The last three pairs of caudal appendages are nearly of the same length, and the central tail-piece is emarginate at the apex. Several specimens of this species were taken by Pro- fessor Kinahan, from the branchial cavities of Rhizostoma Cuvieri. The specimen from which our figure and de- scription were taken is preserved, in an imperfect state, in the Dublin Museum. M. Guérin-Meéneville had some specimens in his collection, procured on the western coast of England. The circumstance of this animal having been found inhabiting the gill-cavities of a Medusa establishes another link associating this subfamily more closely with the Hyperina than was at first presumed. OTUS. 223 AMPHIPODA. PHOXIDES. NATATORIA. Genus—OTUS. Otus. Spence Barr, Cat. Amph. Crust. Brit. Mus. p. 125. Generic character. Cephalon anteriorly produced. Pereion distended. Pleon compressed. Antenne simple. Third pair of siagonopoda unguiculate. First pair of gnathopoda chelate ; second subchelate. Posterior pair of pleopoda biramous. Telson single. Tue head is anteriorly produced. The body is much distended, while the tail is considerably narrowed. The antennz are subequal in length, the upper being the more robust, and not furnished with a secondary ap- pendage. The mandibles possess a three-jointed ap- pendage. The maxillipedes terminate in a small nail. The first two pairs of legs are small, and of nearly equal size, the first terminating in a distal double- fingered claw ; the second, which is rather stouter than the first, being only subchelate. The coxe of the four anterior pairs of legs are deep, the fourth being also very broad, and posteriorly deeply excavated to receive the anterior lobe of the coxa of the fifth pair. The walking legs are short and strong, and furnished with sharp fingers. The three posterior pairs of caudal ap- pendages are double branched, and the central tail-plate is single and scale-like. This genus bears a near resemblance to Iphimedia, but is distinguished from it by the form of the maxillipedes, and by the character and proportions of the first two pairs of legs. The near approximation of the characters of the two genera suggested the name of the son of [phimedia as being appropriate for the present more recently disco- vered form. 204 GAMMARID&. AMPHIPODA. PHOXIDES. NATATORIA. OTUS CARINATUS. Specific character. Pereion furnished with a dorsal carina, Third seg- ment of the pleon having an elevation near the dorsal centre, and the posterior margin produced into a sharp tooth near the centre on each side, Length 3 inch. 3 Otus carinatus. SpeNce Batr, Cat. Crust. Amph. Brit. Mus. p. 126, pl. xxiii. fig. 2. Tue head is very short, but produced anteriorly to a sharp point, slightly depressed. The back is furnished with a small but distinct median carina, The third seg- ment of the tail is abruptly elevated near the middle, and again gradually depressed to the posterior margin. On each side the posterior margin is posteriorly pro- duced, near the centre, into a long slightly-upturned tooth. The eyes have not been observed. The superior antenne are short, being scarcely more than twice the length of the upper margin of the head; the peduncle OTUS CARINATUS. 995 is more robust than the flagellum, and about the same length. The inferior antennz are not longer than the superior, but not so stout, and terminate in a flagellum scarcely longer than the last joint of the peduncle. The mandibles are deep and narrow, and the maxillipedes are short, and furnished with a broad plate, reaching nearly as far as the finger. The first pair of legs have the hands with the lower distal angle produced into a sharp process, nearly equalling the finger in length; the finger is slender, and tipped with a distinct nail, at the base of which arise two or three hairs. The second pair of legs are a little larger than the first, and have the hand some- what triangular in form, the palm being straight, but slightly oblique and distinctly pectinated ; the finger is sharp and curved. The coxe of the first four pairs of legs are deep, increasing gradually to the fourth, which is much broader than the others, and deeply excavated on the posterior margin towards its upper limits, in order to receive the anterior lobe of the coxa of the next succeeding pair of legs. All the walking legs are short and stout; the thighs of the three posterior are broad, and posteriorly developed into two angles. The last pair of caudal appendages have the branches un- equal in length; they are sharp, straight, and clean. The terminal plate is lanceolate. The animal was first taken by that veteran dredger, the late Mr. Barlee, off the Shetland Islands, two or three years since. During the summer of 1861 it has again been taken by the Rev. A. M. Norman and Mr. J. Gwynn Jeffreys, in from seventy to eighty fathoms, about sixty miles east of the Shetland Islands. 226 GAMMARIDA. AMPHIPODA. PHOXIDES. NATATORIA. Genus—PEREIONOTUS. N.G. Generic character. Cephalon short. Pereion distended. Pleon compressed. Antennee very short. Superior longer and more robust. Gnathopoda subchelate, subequal. Pereiopoda short, robust. Antepenultimate pair of pleopoda having the peduncle very short, rami long, subfoliaceous. Penultimate pair having the peduncle long, rami styliform. Ultimate pair short, unibranched. Telson single. Tue head in this genus is very short. The body is very distended, and the tail gradually narrowed to the extremity. The eyes are very small. The coxe of the first four pairs of legs are large, whilst those of the three last are short. ‘The hands of the first two pairs are subchelate. The walking legs are subequal, short, tolerably robust, and terminate in strong sharp fingers. The antepenultimate pair of caudal appendages have the peduncle very short, almost obsolete; and the branches are long, and look like narrow leaves. The penultimate pair have the peduncle strong, and as long as the branches, which are strong, stiff, and naked. The ultimate pair are very short, and support a single very short branch. The central terminal piece consists of a single squamiform plate. This genus bears a near relationship to that of Phlias of Guérin. The only distinction of importance which we are enabled to discover exists in the form of the posterior pair of caudal appendages: these are biramous in the description and figure of Phlias, as given by the PEREIONOTUS, 99% author in the “* Magasin de Zoologie”’ for 1836. Of this latter genus we have had the opportunity of examining only a single specimen of P. Rissoanus, taken by Mr. J. Gwynn Jeffreys on the shores of Piedmont, but the specimen being small, we were not able to make out the form of the last pair of caudal appendages without dissection, and we felt unwilling to destroy our only specimen. We are therefore led to infer either that Guérin’s description of the posterior pair of caudal appendages is incorrect, or that Montagu’s specimen belongs to a distinct but closely-allied genus; and pre- fer to adopt a new generic name, rather than to assume, without further evidence, that so accurate an observer as M. Guérin-Méneville can have been mistaken. The accompanying vignette is a scene off Flamborough Head. Q 2 298 GAMMARID®. AMPHIPODA. PHOXIDES., NATATORIA. PEREIONOTUS TESTUDO. Specific character. All the segments of the pereion, and the first of the pleon, elevated into a strong dorsal carina, the apex being longitudinally shorter than the base, in every segment except the first of the pleon, in which the carinated process is posteriorly produced to a round point. Length 3, inch. Oniscus testudo. Monvaau, Linn. Trans. ix. p. 102, t. v. fig. 5. Leacu, Edin. Eneye. vii. p. 405, gen. Ixvi. (not of Gosse and White). Tue head is short and anteriorly depressed, possessing but a very minute central point between the antenne. All the segments of the body are dorsally elevated into a carina, flat at the top. The first segment of the tail is likewise similarly elevated, but is projected pos- teriorly, the carina terminating in a round process ; each of the segments of the body is also marked by a small tubercle at the infero-anterior angle. The su- PEREIONOTUS TESTUDO. 229 perior antenne are short, being a little longer than the head; the first two joints of the peduncle are very stout; the rest are slender. The inferior antenne are not more than half the length of the superior, and very slender. The coxe of the four anterior pairs of legs are very large, the first being projected anteriorly as far forwards as the eyes. The first two pairs of legs are subequal and alike in form; the hands are scarcely broader than the rest of the leg, rather more than as long again as broad, and furnished with small hairs on the inferior surface, but without any clearly-defined palm; the fingers are thick, short, slightly curved, and terminating in an obtuse point. The walking legs are of uniform length ; they are short and strong, and terminate in short stout fingers; in the three posterior the thighs and metacarpal joints are considerably dilated. The ante- penultimate pair of caudal appendages have the peduncle so short, that we could not detect it in our examination ; while the branches resemble long narrow leaves, of un- equal length and breadth, having the margins slightly fringed with cilia. The penultimate pair have the peduncle long and stiff, while the branches are unequal in length, styliform in shape, and not longer than the peduncle. The ultimate pair are very short, scarcely reaching beyond the middle tail-piece, and terminating in a single branch, not more than half the length of the peduncle. The tail-piece is almost disc-shaped. This species was imperfectly described and figured many years since, by Col. Montagu, in the “ Trans- actions of the Linnzan Society,” from a specimen taken by him at Salcombe, on the coast of South Devon. Montagu made his drawing from the specimen when the tail was closely rolled beneath the body, as we have also done in fig. 2. He consequently represented an ani- 230 GAMMARID®. mal which rather resembled an Jsopod than one of this order of Crustacea. The animal has therefore, for many years, been passed over, and Mr. Spence Bate, who was not aware of its preservation in the British Museum until recently, has omitted it from his ‘‘ Museum Cata- logue of Amphipod Crustacea,” having followed the erroneous assumption of Mr. Gosse and Mr. Adam White, that Oniscus testudo of Montagu was a species of Owen’s genus Acanthonotus. The accompanying vignette of figures, in the pic- turesque costume of Normandy, is from a picture in the possession of Mr. Hames, of Chagford. ACANTHONOTUS. aot AMPHIPODA. PHOXIDES., NATATORIA. Genus—ACANTHONOTUS. Acanthonotus. Owxn, App. to Ross’s Second Voyage N. W. Passage, p. xe. Wairr, Hist. Brit. Crust. p. 177. Gossz, Man. Mar. Zool. p. 142. Muitnu-Epwarps, Hist. Crust. t. iti. p. 24. Spence Bare, Cat. Crust. Amph. Brit. Mus. p. 126. Tertumnus, Leach MSS. Wurtz, Cat. of Crust. Brit. Mus. 1847. Generic character. Cephalon produced anteriorly. Antenne simple, subequal. Mandibles with a tri-articulate appendage. Coxe narrow, deep, and pointed, except the two last, those of the fourth legs lunate, with a strong tooth. Gnathopoda slender, feeble, subchelate. Pereiopoda subequal. Dactyla unguiculate. Posterior pair of pleopoda biramous. Telson single, cleft at the apex. Tue front of the head is considerably produced into a point, curved downwards. The segments of the body are short, whilst those of the tail are long. The an- tennz are nearly of the same length (about one-fourth of the length of the animal); the superior do not possess a secondary appendage. The arms are uniform, subequal, slender, feeble, and subchelate. The coxe of the first four pairs of legs are deep, narrow, and pointed, those of the fourth pair are sickle-shaped, having, moreover, a strong central tooth on the posterior margin. The walking legs are subequal, and have the fingers terminat- ing ina sharp nail. The last pair of caudal appendages consist of two styliform branches, and the terminal plate is single, but cleft at the apex. This genus was founded by Professor Owen, for a species of Amphipod brought from the Arctic Regions by Sir John Clark Ross. 232 GAMMARIDA, AMPHIPODA. PHOXIDES. NATATORIA. ACANTHONOTUS OWENII. Specific character. Posterior segments of the pereion, and anterior ones of the pleon, dorsally elevated into carinal teeth. Antenne scarcely one- fourth the length of the animal. Gmnathopoda slender. Telson deeply cleft. Length 3 inch. Acanthonotus (?) Owenti. Spence Barr, Rep. Brit. Assoc. 1855, p. 58. Ann. Nat. Hist. 2 ser. vol. xix. p. 141. Acanthonotus testudo. Waitt, Cat. Brit. Crust. p. 51 (1850). Pop. Hist. Brit. Crust. p.177. Spence Bats, Cat. Amph. Crust. Brit. Mus. p. 127, pl. xxiii. fig. 3. Gossz, Man. Mar. Zool. p. 42 (1855) (not Oniscus testudo, Mont. see ante, p. 228.) Vertumnus Cranchti, Leach MSS. Wurtz, List Crust. Brit. Mus. p. 89, 1847. Acanthonotus Cranchii. Wuitr, Cat. Crust. Brit. Mus. p. 57, 1847. Tue head is anteriorly produced to a point, deflexed between the antenne. The last segments of the body, and the four anterior of the tail, are elevated into a ca- rina; the middle of the posterior margin of each segment is produced into a strong tooth; the three anterior seg- ACANTHONOTUS OWENII. 233 ments of the tail likewise possess a lateral ridge, and the posterior margins are denticulated; the fourth segment of the tail is marked by a deep sinus across the dorsal surface. The eyes are round and prominent. The superior antennz are stouter at the base than the inferior, and are also a little longer. The coxe are deep, narrow, and terminate in a point, those of the fourth pair of legs being the largest, sickle-shaped, and armed with a strong curved spine on the hind margin. The first two pairs of legs are very similar; the wrists are a little longer than the hands; the hands have no clearly-defined palm; and the fingers are very short. The rest of the legs are very nearly of the same length ; the thighs of the three posterior gradually increase in width: they have the anterior portion thick, whilst the posterior is suddenly reduced to a thin scale, so that the legs, when folded up, lie compactly together in a groove. The three posterior pairs of caudal appendages are subequal, the branches being of uniform length, styliform, and free from hairs. The tail-piece is deeply cleft.* This animal, according to specimens received from the Rev. A. M. Norman and Mr. Jeffreys, is of a fawn colour striped with red, the red bands corresponding with the posterior margins of the segments and joints of the animal. In this it appears to differ from an American form, A. serratus, Fabricius, as described by Stimpson, where the anterior half of each segment is pink, and the posterior white. * The figure representing this animal was drawn from a specimen in the British Museum, while the description is taken from a specimen captured in the Moray Frith. They disagree in some unimportant points ; the telson being less cleft in the figure than in the description, and the hands are more dis- tinctly subchelate in the former than the latter. 234: GAMMARIDA. In some specimens of the young animals, when just enabled to quit the parent, we have observed that the superior antennz are furnished with a secondary appen- dage, formed of a single articulus. This species is rather plentifully distributed ; we have received specimens from the Moray Frith, sent us by Mr. Edward and Mr. Gregor. The late Dr. G. John- ston took it in Berwick Bay. Professor Kinahan has taken it in from fifteen to thirty fathoms, on the Scollop Bank, in Dublin Bay. Mr. Webster has dredged it at Falmouth ; and Mr. Jeffreys and the Rev. A. M. Norman have found it in from seventy to eighty fathoms, sixty miles east of the Shetland Islands. The following vignette represents the Drogns, from a sketch by Dr. Scott, of Melby, staff-surgeon, R.N. GAMMARIDES. 935 AMPHIPODA. GAMMARIDES. NATATORIA. Subfamily—GAMMARIDES. Body compressed. yes two, situated on a lobe between the superior and inferior antenne. Inferior antenne not situated posteriorly to the superior. Posterior pair of pleopoda folia- ceous. Tue animals constituting this subfamily are generally much compressed laterally. They have two eyes, which are situated on a lobe of the walls of the head, which project anteriorly between the superior and inferior antennee. The antenne are planted one above the other, and are generally long, slender, and terminate in a fila- mentary flagellum. The first two pairs of arms are subchelate, and generally well developed. The posterior pair of caudal appendages are generally leaf-like, and fringed with cilia or hairs, but never stout spines or hooks. ‘The terminal tail-piece is generally squamiform, except in one or two genera, where it appears to be tubular or cylindrical, resembling a rudimentary seg- ment. This subfamily must be considered as containing the normal types of the order, the others being greater or less departures from this perfect form. They are in- variably aquatic animals, existing in fresh as well as sea water; and are most numerously distributed on our shores. 236 GAMMARID#. AMPHIPODA. GAMMARIDES. NATATORIA. Genus—DEXAMINE. Dexamine. Leacu, Edin. Encye. vii. p. 433. Spence Bate, Cat. Amph. Brit. Mus. p. 130. Acanthonotus (pars). Mrune-Epwarps, Iist. des Crust. iii. p. 25. Generic character. Superior antenne having the third joint of the peduncle reduced in size, so as to resemble the first articulus of the flagellum; without a secondary appendage. Mandibles having no, appendage. Gnathopoda feeble, subche- late. 'Telson single, divided. In this genus the antenne are of moderate length, slen- der, and nearly of corresponding proportions ; both pairs are remarkable for the absence of a joint in the pe- duncle ; but this absence is probably more apparent than real, arising from the last joint in each being reduced to the form and appearance of the articuli of the flagellum. The mandibles are not furnished with an appendage, a peculiarity especially characteristic of the ORcHESTID&. The first two pairs of legs are subchelate, although slender. The coxz of the four anterior pairs of legs are subequally deep and rounded; those of the three posterior are scarcely more than half as deep as the preceding. The posterior pair of caudal appendages are two-branched, and the central terminal plate is single, but constantly divided to a considerable extent down the middle. This genus was founded by Dr. Leach, to receive a species described by Montagu under the name of Cancer (Gammarus) spinosus, but it was not accepted by Prof. Milne-Edwards, who referred Montagu’s species to the genus Acanthonotus. DEXAMINE SPINOSA. OS AMPHIPODA, GAMMARIDES, NATATORIA., N cc AE oS => VRS ys DEXAMINE SPINOSA. Specific character. Each of the four anterior segments of the pleon ele- vated into a large posteriorly-directed tooth ; first joint of the peduncle of the upper antenne with a blunt tooth. Length 3 inch. Cancer (Gammarus) spinosus. Montaav, Linn. Trans. vol. xi. t. ii. fig. 1. Dexamine spinosa. Luacu, Edin. Encye. vii. p. 433. Zool. Mise. ii. p. 23. Linn. Trans. xi. p. 859. Ene. Brit. Suppl. i. 425. Samovee, Ent. Comp. p. 102. TxHompson, Nat. Hist. Treland, iv. p. 395. Dxrsmarzst, Consid. sur les Crust. p. 263, pl. xlv. fig. 6. Wurst, Cat. Brit. Crust. (1849), p. 49. Hist. Brit. Crust. p. 178, pl. x. fig. 7. Spence Bats, Brit. Assoc. Rep. 1855, p.58. Ann. Nat. Hist. 2 ser. xix. p. 141, 1857. Cat. Amph. Brit.Mus. p. 130, pl. 24, fig. 1. Amphithoé Marionis. Mitne-Epwarps, Ann. des Sci. Nat. xx. p. 375. Hist. des Crust. t. iii. p. 40. Cuv. Régne Anim. Edit. Crochard, pl. 60, fig. 6. Acanthonotus ? spinosus. Mityzu-Epwarps, Hist. des Crust. iii. p. 25. Amphitoé spinosa. GossE, Mar. Zool. p. 141, f. 266. Tue head has the anterior margin produced in the centre into a little flat rostrum. The body of the ani- 2938 GAMMARID. mal is smooth. The tail has the four anterior segments with the dorsal margin in each posteriorly produced and elevated into a strong tooth; the fourth is also marked by a dorsal sinus. The eyes are oblong. The antennz are subequal, slender, the superior having the two joints of the peduncle of nearly the same length, the first joint being furnished, at the infero-distal extremity, with a blunt tooth. The inferior antenne are a little shorter than the superior, and have the penultimate joint of the peduncle pubescent upon the upper surface. The first two pairs of legs are slender, and not very strong; the hands having the palms oblique, and minutely pectinated, the anterior being the more coarsely marked. The next two pairs of legs are very slender and feeble, but the last three are somewhat more robust, and generally carry the fingers directed backwards. The caudal appendages reach nearly to the same length, and have their branches equal. In Montagu’s type specimen in the British Mu- seum the middle pair of appendages are rather shorter than the others. The terminal plate is very long, and split to about two-thirds of its length; the margins are fringed with a few hairs, and the apex armed with a single spine on each side of the central division. This very pretty species, which for a long time ap- peared to find no generic resting-place, was first figured and described by Montagu, but his description was so short, and his figure so imperfect, that Prof. Milne- Edwards was unable to identify it with the species that he described and figured under the name of