302 



MUSEUM OF ANIMATED NATURE. 



[Crabs. 



fluviatilia, a fresh-water crab found in the south of 

 Europv. 1, the right internal jaw-loot; A, its inter- 

 nal blade ; a, b, c, d, e,f, its various articulations ; 

 B. its external blade, or flabelliform palp: 2, jaw of 

 the fourth pair with its palp: a, jaw of the third 

 pair with lU palp : -J, jaw of the second pair : 5, jaw 

 of the first pair : 6, mandible with iu palp : 7 the 

 upper lip : 8, the tongue, a sort of horny lamellar 

 process performing in some degree the functions of 

 a lower lip. 



Fig. 31U1, the claw or chelie of Thelphusa fluvi- 

 atilis. a, the moveable finger opposed to the im- 

 moveable finger j b, of the claw ; c, the carpus, or 

 wrist. 



Fig. .3102, the posterior foot of Thelphusa fluvi- 

 atilis. a, the haunch; b, the trochanter; c, the 

 thigh ; d, the leg : e, the metatarsus ; /, the tarsus. 



Fig. 3103, the antennte of Thelphusa fluviatilis. 

 <i, the right external antenna ; b, the large antenna 

 of the same side. 



ORDER DECAPODA. 



Bra>'CHI.b fixed to the sides of the thorax, in re- 

 spiratory cavities; the oral apparatus composed of 

 SIX pairs of members. True limbs five pairs. 



Section Brachyura — short -tailed Decapods, as 

 Crabs. The Brachyura, or crabs, have their form 

 far better adapted fur walking on the shore, or at 

 the bottom of the sea, than lor swimming. The 

 cephalo-thorax is developed ; the antennae are short : 

 the tail, or more properly the abdominal portion, is 

 greatly reduced, and when not used is kept bent 

 under the thorax, and lodged in a depression be- 

 tween the origin of the legs. The branchiae are 

 under the edge of the carapace in the form of 

 broad lamellie laid over one another, and there are 

 three flabella on each side derived from the roots of 

 the jaw-feet, of which two are embedded amongst 

 the branchiaj, while the third, in a crescentic form, 

 extends over the whole series. 



In some crabs all the feet, excepting the chelae, 

 end pointed, as in the common crab; but in crabs 

 more especially adapted for swimming, the hinder 

 pair of limbs are terminated by compressed paddles, 

 or oar-blades. 



Most who have wandered along the shore of the 

 sea at low tide have observed shoals of crabs run- 

 ning quickly about in their sideway manner, and 

 endeavouring when approached to hide themselves 

 under stones, or bury themselves in the sand. It is, 

 indeed, far more common for the crab thus to ap- 

 proach the shore than the lobster, for the former is 

 far more terrestrial ; yet both, provided the gills are 

 kept moist, will live a long time out of their native 

 element. Some species, indeed, are almost exclu- 

 sively terrestrial, visiting the sea only at certain 

 periods, and again returnmg to the land where they 

 live in deep burrows. 



The large edible crab (Cancer Pagurus), Le crabe 

 poupart, ou tourteau, of the French, is too well 

 known to need description ; it may be taken as the 

 type of brachyura. It is much esteemed as a deli- 

 cacy for the table, but previously to moulting, 

 and during the time in which it is destitute of its 

 armour, its flesh is soft, watery, and very unpleasant. 

 On the contrary, some of the crabs in the West 

 Indies, and America, are at that season in their 

 highest perfection. A writer in the ' American 

 Cyclopaedia ' says, " Myriads of crabs are caught on 

 the shores of the rivers and creeks of the Chesapeake 

 Bay, when in their soft state, and sold to great ad- 

 vantage. The epicure who has never tasted soft 

 crabs should hasten to Baltimore, Annapolis, or 

 Kuston in Maryland, in July and August, to make 

 himself acquainted with one of the highest luxuries 

 of the table." 



The powers of vision, smell, and taste, are enjoyed 

 by the crab in great perfection. With regard to 

 smell, though, as has been well observed, every creel 

 baited for the capture of these animals and lobsters 

 proves them to be endowed with it, yet where the 

 organ is seated is a matter of doubt. 



The large edible crab. Cancer Pagurus, is partial 

 to rocky coasts, and is taken around those of our 

 island in great abundance. Crab-fishing is gene- 

 rally conducted by two men, who go out in one 

 boat ; in addition to their boat, they have lines, and 

 creels, cruives, or crab-pots, as they are termed in 

 various counties, the original cost of which amounts 

 to about ten pounds. These creels are made of dry 

 osiers, and resemble basket-work. They are con- 

 structed on the same principle as a wired mouse-trap, 

 but the aperture, instead of being at the side, is at the 

 top. Within the creel, the bait, consisting of pieces 

 of thornback, skate, or other fish, is fastened to the 

 bottom, and the creel is then dropped in some fa- 

 vourable situation, three stones of sufficient weight 

 being fastened in the inside to sink it. The creels 

 are sometimes let down to a depth of twenty fa- 

 thoms, the fishermen being guided in this respect 

 by the state of the weather, or the nature of the 



ground. In fine weather they are dropped in from 

 three to five fathoms deep : but the crabs are chiefiy 

 to be found where the l>ottom is rocky. A line is 

 fastened to the creel, and at the upper end of the 

 line a cork is attached which floats on the surface. 

 Hy this means the place where the creel is sunk is 

 known to the fishermen, who usually set from forty 

 to fifty creels at one time. The bait is suitpended 

 about the middle of the creel, and can easily be 

 seen by the crabs, which, entering ut the aperture, 

 find, like a mouse in a wire trap, that escape is im- 

 possible. The difficulty of egress is increased by 

 the entrance being overhead. Lobsters, prawns, 

 and shrimps are frequently found captured in the 

 same creel with crabs. When the fishermen have 

 sunk the whole of their creels, they have still some 

 time left to proceed farther out to sea for other fish 

 before it is necessary to visit them. Ciub-fishing 

 is therefore a valuable addition to their means of 

 livelihood, for it does not preclude the pursuit of 

 other fish at the same season. The demand for this 

 species of shell-fish is usually good, and in the 

 nearest large town on many parts of the coast it is 

 often fully equal to the supply. Thither the fisher- 

 man's wife, or some of his family, may convey the 

 quantity taken ; and, if the market be already abund- 

 antly provided, they can by means of the well-boxes, 

 although already caught, he kept back for a time 

 until prices rise again. These are all advantages 

 peculiar to this fishery. When a few hours have 

 elapsed, the fishermen visit their creels, one of them 

 rowing and the other keeping a look-out for the 

 floats, and taking out of the creels whatever has 

 been captured. There may perhaps be a dozen dif- 

 ferent owners of boats thus engaged, and it is there- 

 fore necessary to have recourse to some means by 

 which they may each secure the fruits of their indi- 

 vidual industry without the risk of dispute. This is 

 accomplished by distinguishing their respective 

 floats by some peculiar mark — by a notch in the 

 side — a mark in the shape of a diamond cut at the 

 top — an angle cut off, &c. &c. The necessity of 

 mutual protection points out to them the value of 

 combination and union, and the marks adopted by 

 the fishermen to distinguish their floats are conse- 

 quently the result of some common understanding 

 amongst them; or otherwise of an instinctive regard 

 to the means by which not only one but all are 

 enabled to pursue their calling in confidence and 

 security. 



Crabs are brought to market both in a boiled and 

 in a raw state. If the market be distant they are 

 placed in a well-box which is attached to the out- 

 side of the fishing-vessel, and in this manner they 

 are brought to Billingsgate from parts so distant as 

 Norway. May, June, and July are the months in 

 which they are generally out of season; but even in 

 these months many may be obtained which are in a 

 perfectly good state for the table. The male is of 

 greater value than the female, and has larger claws. 

 The sexes are distinguished as the cock and the 

 hen. Before boiling, a good crab is known by the 

 roughness of its shell, particularly on the claws. 

 When boiled, the mode of ascertaining its goodness 

 is by holding the claws tight, and shaking the body, 

 which will rattle, or seem as if water were in the in- 

 side, if it be not in perfection. The time they are 

 usually boiled is from a quarter of an hour to a 

 couple of hours in sea-water, or in water in which 

 salt has been infused. Sometimes they are put into 

 cold water which is afterwards heated to the boil- 

 ing point ; and this mode is believed to be less cruel 

 than plunging them suddenly into water heated to 

 a high temperature, though it is alleged they are 

 inferior for the table when the former method is 

 ernployed. 



Fig. 3104 represents a scene which may be often 

 contemplated on different parts of our coast, fisher- 

 men hauling up their creels for examination. Fig. 

 3 1 05 gives a good idea of the implements used in the 

 crab and lobster fishery, a, creels or crab-pots ; b, 

 a lobster-pot, of cordage or netting on hoops ; c, a 

 well-box, for preserving the animals. 



We shall now pass to a review of our pictorial 

 specimens ; stopping only to notice those species to 

 whoiiC history a more than ordinary interest is at- 

 tached. 



Fig. 3106, PoTtunus variegatus. This species, 

 one of the paddling crabs, is closely allied to the 

 Carcinus msenas of our coasts : but has the posterior 

 limbs still more paddle-formed. It is a native of 

 the Adriatic, and the Medilenanean. a, the ex- 

 ternal antenna ; b, the external jaw-loot ; c, the tail 

 or abdomen. 



Belonginsr to the same natural group are several 

 genera, as Portunus, of which the orbits, antennae, 

 and jaw-foot, are represented at Fig. 310" ; and one 

 of the species, Portunus puber, at Fig. 3108. This 

 species, the Cancer velutinus of Pennant, is about 

 two inches and a half long; and is found on the coasts 

 of England and the adjacent continent. It is the 

 Criibe k laine, the Crabe espagnol and lY'trille of the 

 French. Its flesh is accounted very delicate. Its 



posterior limbs may be compared with those of Car- 

 cinus menas. Fig. 3109, the Carcinus raitnas (feet 

 of), le Crabe enrage, or small common crab, is ex- 

 tremely common on our coasts and those of Fiance. 

 It may be seen at low water running on the shore 

 with great rapidity ; and when approached it buries 

 itself in the sand. Though not much esteemed this 

 crab is eaten both in London and Paris. We have 

 seen baskets full hawked about the streets of our 

 metropolis and the suburbs. 



Another allied form is the genus Platyonichus, 

 of which the P. bipustulatus, Fig. 3110, is an ex- 

 ample. It is of moderate size, and inhabits the 

 Indian Seas. We may here notice the genus Poly- 

 bius, in which all the feet, excepting the chelae, are 

 formed for swimming; the posterior pair are short 

 and broad. A small species, Polybius Hensiowii, 

 Fig. 311 1, is found in the British Channel, but gene- 

 rally keeps at a distance from shore. 



Among the more exclusively marine genera is 

 that termed Lupea. The species are seen in the 

 open ocean, swimming with great address near the 

 surface, where, as Bosc remarked, these crabs have 

 the power of suspending themselves motionless, in 

 a state of repose. They haunt masses of drilling 

 sea-weeds, and there find both a retreat and food. 

 The caraijace is remarkable for its transverse extent, 

 and for the strong serration of its anterior margin. 

 The anterior limbs, which are robust, are more or 

 less armed with spines. The Lupea cribraria, Fig. 

 3112, is of small size, attaining to tne length of three 

 inches. It inhabits the seas of Asia. Its colour is 

 yellowish with numerous whitish spots. 



The Lupea pelagica (Portunus pelagicus, Fabr.), 

 Fig. 3113, is remarkable for the length of the last 

 lateral spines of the carapace. It is an active 

 swimmer, inhabiting the Red Sea, and the whole of 

 the Indian Ocean. 



Still more remarkable is the Lupea forceps 

 (Fig. 3114), a small crab from the seas of the An- 

 tilles. Its last lateral spine on each side is con- 

 siderably elongated, and the fore claws are pro- 

 duced into blender and very long pincers, so that 

 the anterior pair of limbs far exceed the four suc- 

 ceeding pairs. 



Among the Swimming Crabs we may notice the 

 genus Thalamita, in which, from the width of the 

 frame-work of the mouth, the eyes are Ihrown 

 greatly apart, and the third joint of the last pair of 

 limbs is elongated, and has a spine at the extremity 

 of its anterior border. These points are peculiarly 

 manifest in Thalamita Chaptallii (Portunus Chap- 

 tallii, Aud.), Fig. 3115; in which species the an- 

 terior maririii of the carapace between the eyes is 

 smooth. It is a native of the Red Sea, is not more 

 than an inch in length. 



In the Indian Ocean is found a very pretty 

 species, the Thalamita ciucifera. Fig. 3ilC; the 

 border of the carapace between the eyes is denti- 

 lated, and on each side below the eyes are six 

 serrations. Its general colour is reddish, with 

 yellow bands and markings, a median mark on the 

 carapace resembling a cross in figure. It is the 

 Portunus crucit'erus of Fabricius. 



Another species, Thalamita natator (Portunus 

 sanguinolentus, Bos), Fig. 3117, has the anterior 

 limbs not only very spinous, but also studded with 

 tubercles and the anterior margin of the cai'apace is 

 serrated. It is a native of the Indian Ocean. 



Among these genera ofswimniing-crabs, one of the 

 most singular is that termed Podophthalmus ; the 

 eyes, which are placed upon short peduncles in the 

 previous genera, are in this seated at the end of long 

 moveable foot-stalks; these are inserted near the 

 median line of the anterior edge of the carapace, and 

 consist of two portions, the first very long, the second 

 very short; whereas in the Ocypodian ciabs, which 

 also have footstalks of the eyes long, it is on the de- 

 velopment of the second piece, and not of the first, 

 that their length depends. These footstalks can be 

 received for safety each into a long deep gutter, on 

 the anterior border of the carapace. The antennae 

 are below the ocular footstalks. Fig. 31 18 represents 

 one of the ejes, peduncles, and jaw-feet of Podoph- 

 thalmus. The only species, we believe, hitherto 

 known is the Podophthalmus vigil (Portunus vigil, 

 Fabr.), Fig. 3119, a native of the Indian Ocean. It 

 is from two to four inches in length. 



We may now pass to those genera composing 

 what Cuvier calls Les Crabes proprement dits, of 

 which the Cancer Pagurus is an example. He re- 

 marks that the third articulation of the outermost 

 jaw-feet is notched or marked with a sinu> near the 

 internal extremity, and is almost square. The 

 antennae are short or moderate. Close to the genus 

 Cancer he places the genus Xantho, in which the 

 antennae are inserted into the internal angle of the 

 ocular cavities, and not outside, as in thu former. 

 Fig. 3120 represents the Xantho floridus, common 

 on our coasts and those of France, a, the external 

 jaw-foot; b, external antenna. This is a small 

 species, about two inches in length, of a reddish 

 brown colour, with black claws. 



