314 



MUSEUM OF ANIMATED NATURE. 



[Hermit-Cbabs. 



To the CorystiaiuM. Milne Edwards refers several 

 genera, as Atelecylus, Thia, Corvstes, &c. To the 

 Doiippiaiis he refers Dorippe, Klluisa, &c. 



The scvnen. Thia. Dorippe, Eihusa, &c., have al- 

 ready been ilhistrated ; for in the foregoinR sketch 

 of the Brachyiirous Crustacea, we have not bound 

 ourselves to the selection of any system, out of the 

 many drawn up by various lOoloRists ; our aim has 

 been rather to give a general view of the leading 

 characters of the Orusttcea,and of the princinal va- 

 riations of form which obtain among them, than to 

 elucidate any Iheoietic arrangement. As, however, 

 the celebrated ' ROgne Animal ' of Ciivicr is that to 

 which most beginners in the study of zoology apply, 

 we may say that in the fourth volume of that work 

 l,atreille divides the Brachyura into— i. Ptnnifeda. 

 Examples: Matutor, Polybius, Potlophthalmus, Por- 

 tunus. &c. ii. Arcuuta. Examples: Cancer, 

 Xantho, Thia, Hepatus, &c. iii. Quadhlateia, 

 Examples: Eriphia, Pilumnus, Thelphusa, Gono- 



S'llax, Gelasimus, Ocypoda, Pinnotheres, Uca, 

 ecarcinus, Grapsus, &c. iv. Oibicvliila. Exam- 

 ples : Corystes, Leucosia, Persephone, &c. v. Tri- 

 qima. Examples: Maia, Parlhenope, Mithrax, 

 Euryonome, Acanthonyx, Micippa, Stenocinops, 

 Camposcia, Halimus, Hyas, Docliea, Machus, Ste- 

 norhjnchus, &c. vi. Cryptojtoda. Examples : Ca- 

 lappa,CElhra. y'i\. Notopoda. Examples; Ilomola, 

 Dorippe, Uromia, Uanina, &c. 



In the arrangement of this writer there is no sec- 

 tion termed Anomoura, or Anomura, which is that 

 upon which we shall next enter. 



SECTION ANOMOURA, or ANOMURA. 



(Decapod Crustaceans with a development of the 

 abdominal region intermediate between the Brachy- 

 uraand the Macrura, and with the posterior limbs 

 presenting certain modifications). This section, as 

 established by Milne Edwards, contains several forms 

 which Latreille assigns to his Notopod Biachyura, 

 as Floniola, Ranina, &c., which present as it were 

 the links of union between the Biachyura and the 

 Anomura : while on the other side, Birgus, Por- 

 cellana, CEglea, and Galathea link the latter to the 

 Maerura. 



The genera Homola, Lithodes, and Lomis, form 

 a small group having the carapace spiny, and fur- 

 nished anteiiorly with a rostrum. The internal an- 

 tennae are incapable of being bent back upon the 

 front ; the jaw-feet are pediform ; the anterior limbs 

 are furnished with claws; the second, third, and 

 fourth pairs are very long, the filth pair are very 

 short, and of no service in progression. 



In the genus Homola the carapace is longer than 

 wide, and nearly quadrilateral ; the front is narrow, 

 and advances to form a small rostrum ; the orbits 

 are incomplete; the external antennae rather long. 

 The limbs are veiy long ; the fifth pair are raised upon 

 the back, and terminate in subchelil'orm holders. 

 The abdomen consists of seven segments, and in the 

 female the first segment carries a pair of short ap- 

 pendages, differing from those of the four succeed- 

 ing segments, which are as in the Brachyura. 



We select as an example the Homola spinifrons. 

 Fig. 3190, found in the Mediterranean. It is about 

 an inch and a half in length, and covered with yel- 

 low hairs, a, the left external jaw-foot. 



In the genus Lithodes the caiapace is heart- 

 shaped, and the last thoracic ring is not soldered to 

 the preceding, but free and even moveable. The 

 fifth pair of limbs are extremely small, and bent 

 back in the interior of the branchial cavities. The 

 abdomen is large and triangular. The rostrum is 

 moderate. 



The Lithodes arctica (Fig. 3191) is a native of 

 the Arctic Seas. It measures about five inches in 

 length, and is of a reddish yellow colour, a, the left 

 external jaw-foot ; b, the abdomen ; c, a foot of the 

 filth pair. 



With respect to the genus Lomis, it is founded by 

 Milne Edwards on a small crustacean supposed to be 

 from the Australasian Seas ; of its habits nothing is 

 ascertained. 



Another small group is represented by the genus 

 Ranina. It is characteiized by the carapace being 

 convex laterally, and gradually narrowed posteriorly ; 

 the ocular peduncles are lodged in the orbits, but 

 are bent, and composed of three moveable pieces. 

 The anterior limbs are very much compressed, and 

 the remainder are flattened and wide, and terminate 

 in swimming paddles. 



Fig. 3192 represents the Ranina dentata : a, seen 

 from above ; 6, from below. It is a native of the 

 Indian Seas. Though from the form of the limbs of 

 this crustacean we should infer almost exclusively 

 aquatic habits, yet Rumphius informs us that it 

 comes to land, and creeps even to the tops of houses. 

 Another group is represented by the genus Pactolus, 

 in which we find the anterior limbs terminated with 

 a simple hooked point, instead of a claw ; the 

 two posterior pair are furnished at the end with 

 pincers. The carapace is elongated, and is pro- 



duced anteriorly into a long slender rostrum, at the 

 base of which are the large projecting eyes. 



The only species, Pactolus Boscii (Fig. 3193), is 

 of small size, measuring about eight lines, including 

 the rostrum, which is spiny. The carapace is of a 

 brownish colour; the limbs varied with red and 

 white. Its country is unknown. 



We now advance to a group or small tribe called 

 Hippians by .Milne Edwards; which he says are 

 especially framed for burrowing in the sand, and 

 consequently present extraordinary forms. The 

 carapace is longer than it is wide, and very convex 

 transversely, presenting always on each side a great 

 lamellar prolongation which more or less covers the 

 base of the feet : it is truncated posteriorly and ap- 

 pears to be continuous with the anterior portion of 

 the abdomen, which is very wide and lamellar la- 

 terally. One pair of antennce is always very long. 

 The jaw-feet are peculiarly modified, having neither 

 flagrum nor palp. The limbs are imperlectTy exten- 

 sile ; the first pair have a simple termination, being 

 what is termed monodactylousor subchelil'orm. The 

 succeeding two or three pairs are terminated by a 

 lamellar joint proper for burrowing ; the posterior 

 feet are filiform, semimembranous, curved forwards, 

 and hidden beneath the base of the carapace and 

 the preceding feet The penultimate ring of the 

 abdomen is always furnished with a pair of false feet, 

 terminated with two ciliated blades or laminae of a 

 more or less oval form. To this group belong the 

 genera Albunea, Remipes, and Ilippia. 



In Albunea the ocular peduncles are large and 

 lamellar, but the eyes are very small ; the internal 

 antennae are large and elongated, multiarticulate, 

 and ciliated ; the external antennae are short. The 

 externa! jaw-feet are more or less pediform. The 

 limbs are short, the first pair are subchelilorm, and 

 terminate in a large moveable hook, applying its 

 point to the expanded edge of the joint on which it 

 IS articulated. The three following pairs terminate 

 in a joint, somewhat resembling a broad sickle. 

 The last pair of feet are filiform and hidden. The 

 first ring of the abdomen is very small, and fitted 

 into a notch of the carapace. The second is very 

 large, with a lateral expansion on each side abutting 

 upon the caiapace. The third and fourth segiiients 

 diminish progressively ; the remainder, that is the 

 fifth, sixth, and seventh, are very narrow, and the 

 sixth supports a pair of bifid false feet, for the pur- 

 pose of swimming. 



As an example of this genus we select the Albu- 

 nea symnista (Fig. 3194). It is of small size, and 

 inhabits the seas of Asia. 



In the genus Remipes the carapace is nearly of 

 a regular oval and convex. The anterior limbs are 

 long, and the last joint is slightly flattened, and in- 

 capable of being bent so as to antagonize with the 

 preceding ; the two following pairs of limbs are 

 terminated with pointed paddles; the fourth pair 

 are held by a small joint ; the fifth pair are slender, 

 long, and membranous, and bent upon the lateral 

 prolongation of the carapace. The abdomen is 

 large ; the sixth ring carries a pair of false swim- 

 ming feet; the seventh ring is in the form of a 

 pointed paddle. 



Fig. 3195 represents the Remipes testudinarius, a 

 small species from the coasts of New Holland. The 

 genus Hippa is very closely allied to the preceding. 

 The external antennae are terminated by a long and 

 multiarticulate filament, but arc seldom very visible, 

 being ordinarily bent down and hidden between the 

 mouth and external jaw-feet. The limbs are all 

 short, and terminating in paddle-like laminae. The 

 abdomen closely resembles the same part in Re- 

 mipes. 



Fig. 3196 represents the Hippa emerita, from the 

 coasts of Brazil ; it seldom much exceeds an inch in 

 lensrth. 



We now come to the group called Pagurians, of 

 which the genus Pagurus must be consiilered as the 

 type. Few have visited the shores of our island 

 without having noticed the Paguri, Soldier-crabs, or 

 Hermit-crabs, as they are called, peeping out of the 

 old turbinate shells, in which they have taken up 

 their abode, and of which they guard the entrance 

 with great resolution. In the true Paguri, the ab- 

 dominal portion is destitute of defensive armour, or 

 presents only a few isolated calcareous patches ; and 

 it is from being thus as it were partially defence- 

 less, that they are obliged to resort to a,rtificial 

 means of protection. Consequently they avail them- 

 selves of such shells as are fitted to their size, and 

 entering them backwards, lodge the abdomirial seg- 

 ments in safety, and, are prepared with their claws 

 to defend the gateway of their castle. As they in- 

 crease in size they change their quarters for others 

 more spacious and better suited to their necessities. 

 Thus housed, the Paguri are retained in the shell 

 by the aid of the posterior limbs, and a pair of ap- 

 pendages at the end of the abdomen. 



If we take the common Hermit-crabs of our coast 

 (Pagurus Bernhardus), we shall find that one only 

 of its pincer claws is greatly developed, generally 



the right ; and this, with the first two pairs of loco- 

 motive limbs, which are long, are bent over the co- 

 lumellar edge of the shell, and protrude externally. 

 The two next pairs of limbs are very short, and are 

 applied within the shell to the columellar fold, so 

 that by pushing they force the body farther into its 

 recess. The caudal holders, whicii are as rough as 

 a file, are applied in the same manner, but more 

 deeply within the shell ; and in some species the 

 abdomen is furnished with rows of suckers, by which 

 the hold of the Pagurus must be greatly strengthened. 

 Here then, secure, the animal peers out in quest 

 of prey ; and, dragging his castle after him, traverses 

 the shore, withdrawing himself on the appearance 

 of danger; yet when assaulted, ready, as we have 

 often seen, to engage in a spirited contest. With 

 respect to other parts of their structure we may add 

 that the eyes are directed forwards, and not retrac- 

 tile ; the external antenna; end in a long multiarti- 

 culate filament. 



An allied genus, termed Cenobita, differs in many 

 points from Pagurus ; which in general habits and 

 economy it otherwise closely resembles. The Her- 

 mit-crabs are widely distributed, and were known to 

 the ancients. They haunt low flat shores and shal- 

 lows, where, when the water is clear, they may be 

 seen creeping about, making an irregular progress. 

 Like other crustaceans generally they feed on small 

 marine animals, and dead animal matters which 

 chance throws within their reach. They have the 

 senses of sight and smell very acute ; and the an- 

 tennae are very susceptible. 



It would appear that there are certain species of 

 Hermit-crabs, which are as terrestrial in their ha- 

 bits as the violet-crabs or other land species, and 

 that some even feed on fruits. 



Of such crabs Mr. Broderip received several spe- 

 cimens from Mr. De la Beche ; they were not all of 

 the same species : one was Pagurus (Cenobita) Dio- 

 genes; the other somewhat resembled Pagurus Pri- 

 deaux (Leach). Of the first, there were " forty-two 

 of various sizes, housed in the following marine- 

 shells, which were in every instance well adapted 

 to the bulk of the inhabitant. Two were lodged in 

 Turbo Pica; two in a Natica; one in Bulla striata; 

 there were eight in Fasciolaria tulipa, and twenty- 

 nine in Pyrula nielongena. Of the latter species of 

 Pagurus, the common soldier of Browne, one wa« 

 housed in Fasciolaria tulipa, and nine in Pyrula 

 raelongena. The shells chosen by the last were 

 large in proportion to the bulk of the animal ; so 

 large indeed that some of the Paguri were scarcely 

 visible." 



To these Paguri the following communication to 

 Mr. Broderip from Mr. De la Beche refers; it is 

 dated August 1, 1838 :— 



"When I was in Jamaica, about three years 

 since, some of the persons on my estate at Halse 

 Hill brought me specimens of Paguri, which they 

 said they had obtained from a savannah distant 

 about a "quarter of a mile from the house. This 

 savannah is a p'.ain formed of what I have else- 

 where (' Geol. Trans.' vol. ii., N. S.) termed savan- 

 nah sandstone and conglomerate. It is very dry 

 and covered for the most part with logwood, green 

 ebony, lignum vitae, the cashew-tree, and here 

 and there with patches of grass and other plants. 

 Alter heavy rains the surface of the giound 

 is nearly covered with herbage ; but after dry 

 weather a considerable portion of the soil is ex- 

 posed. The savannah, w liich is of great extent (my 

 portion consists of at least two thousand acres), is 

 about thirty feet above the Rio Minho, which runs 

 round the border of it, and about two hundred feet 

 above the level of the sea, from which it is distant 

 at least ten miles. The tide only penetrates just 

 within the mouth of the river, and rises about eleven 

 inches in the height of the springs, so that there is 

 not even brackish water at a nearer point than ten 

 miles. When the Paguri were brought me they 

 were alive, and I observed that they were housed 

 in marine shells, and at first thought they must 

 have been brought from the sea. Upon inquiring, 

 however, I found that these animals, under the 

 name of soldiers, were frequently taken alive for 

 food in the savannah, to which I immediately pro- 

 ceeded. On its northern side and at its junction 

 with the hill that rises above it, I found in the little 

 hollows of the white limestone several of these 

 Paguri, all in marine shells, and in full health and 

 activity. I afterwards learned that they were by 

 no means uncommon in such situations all over the 

 island. When I saw them there had been a good 

 deal of wet weather. They were in moist places, but 

 there were no pools of water." Another gentleman, 

 who resided some time in the West Indes, informed 

 Mr. Broderip that he had seen the Pagurus 

 (Cenobita) Diogenes about his house when he lived 

 at Port Henderson, and that he had observed them 

 about the houses in Spanish Town, a place about 

 six miles from the sea. Mr. Broderip was also 

 informed that Westmoreland swarmed with them. 

 (See ' Zool. Journal,' vol. iv.) 



