390 



CRUSTACEOLOGY. 



Crustacea, however, still retain the two first pairs of rowers or 

 '— —'/-'»■•' amis. The legs are at this period very visible. About 

 the ninth clay it loses the long oars, and appears still 

 more like the animal in its advanced state." Its growth 

 is but slow, and it is highly prpbable that a very consi- 

 derable time elapses before the insect acquires its full 

 size ; but this the Doctor tells us he cannot presume to 

 determine, as those he kept died before they had acqui- 

 red any considerable size. When first hatched, they 

 are scarcely larger than the common mite. 



Cancer paludosus of Miiller (Zool. Dan. p. 10, tab. 

 48, fig. 1.) is a distinct species, if his figure be correct. 

 It differs in its tentacula and tail. Latreille thinks it 

 very probable that Cancer salinns of Linne, and Cancer 

 paludosus of Otho Fabriciu<:, may also belong to this 

 genus. 



ORDER II. MALACOSTRACA. 



lUlLACOS- 

 TRACA. 



13. PoDOPH 

 THALMUS. 



Vigil. 



14. Por- 



TONUS. 



Pelagicus. 



.Maenas> 



Bllbtr. 



Family VII. Cancerides. 



A. The last joint of the hinder feet flattened, and form- 

 ed for swimming. 



Genus XIII. Podofhthalmus. The peduncle, or 

 footstalk, on which the eyes are placed, as long as the 

 external angles of the shell. 



_ Sp. 1. Vigil. Anterior claws, and external ante* 

 rior angle of the shell, spiny. 

 A native of the shores of India. 



Podophlhalmus spinosus, Lamarck; Porlunus vigil, 

 Fabricius. (Suppl. Ent. Syst. $65.) 



Genus XIV. Portunus. The peduncle of the eyes 

 much shorter than the anterior angle of the shell. 



* Shell with more than five teeth on each side ; hin- 

 der spine very long. Gen. Lupa, Leach's MSS. 



Sp. 1. Pelagicus. The shell on each side with nine 

 teeth, the posterior tooth largest ; hands on the front 

 feet angulated ; the front with four equal teeth ; two 

 teeth-like processes are on each side, at the internal 

 angle of the eyes. 



Inhabits the sea every where, attaching itself to the 

 Fuciu natans, or floating tangle. 



It is Portunus pelagicus of Fabricius; Cancer pelagi- 

 eus of Linne. 



See Lupa in Index. 

 Lupa pelagica, Leach's MSS. 



** Shell with five teeth on each side ; transverse 

 much greater than the longitudinal diameter. 



a Orbit of the eye behind, with one fissure. Gen. 

 Carcinus, Leach's MSS. 



Sp. 2. Mcenas. Shell smooth, with five teeth on 

 each side ; clypeus with three rounded teeth or lobes. 

 When alive green, mottled with black ; hands with one 

 tooth : wrists with a spine. 



Inhabits the rocky shores of the European ocean, 

 lurking under stones and tangle. Vast numbers are 

 sold in London to the poor, who esteem them as great 

 delicacies. The young, or fry, are frequently mottled 

 «r bordei-ed with white. 



Cancer vicenas of Linne, Fabricius, Latreille, Pen- 

 nant, &c. 



6 Orbit of the eye behind, with two fissures. Gen. 

 Porlunus, Leach's MSS. 



1. Hinder nails with an elevated rib; wrists with 

 two teeth. 



Sp. 3. Puber. Shell covered with a velvet-like down, 

 five equal teeth on each side; the front beautifully 

 denticulated; hands striated, with one spine on the 

 upper side ; wrists with two teeth. 



Areuafusji 



Inhabits the Mediterranean and British seas. Crustacea. 



This is Cancer puber of Linne; Portunus' puber of '"■""Y"^*' 

 Fabricius and Latreille ; Cancer veltdinus of Pennant. 



This species, when alive, is a most beautiful animal. 

 The anterior claws are mottled with blue and black ; the 

 eyes likewise exhibit a rich scarlet colour striped with 

 blue. It is by no means uncommon on the rocky coasts of 

 Devonshire, beingfound at low tide under stones and fuci. 

 It is probably the species taken notice of- by Aristotle, 

 on account of the broad feet, which he says assist them 

 in swimming, as webbed feet do the water fowl. 



2. Hinder nails, w T ith an elevated rib ; wrists with 

 one tooth. 



Sp. 4. Corrugatus. Shell with transverse serrate- CemigaftsSj 

 granulated lines, ciliated with hair ; front with three 

 short teeth, middle one largest ; sides with five nearly 

 equal in size ; wrists with a sharp tooth. 



Cancer corrugatus of Pennant. 



Mus. Montagu. 



Sp. 5. Emarginatus. Shell convex, with abbrevia- Emai«is»« 

 ted lines of granules ; sides with five teeth, the fourth tus. 

 smallest ; front notched ; wrists with a strong tooth. 



Porlunus emarginatus, Leach's MSS. 



Discovered at Torcross ; we have seen the female 

 only. 



Mus. Leach. 



Sp. 6. Arcuatus. Front arcuated, in other respects 

 exactly like Portunus emarginatus. 



Mus. Sowerby, Leach. The female has not occur- 

 red. 



Mr Montagu considers this as the male of Portunus 

 emarginatus. Mr Leach thinks that Emarginatus may 

 prove to be an accidental variety of this species ; but 

 considers the distinctions as too strong for usual sexual 

 distinction. 



3. Hinder nails without an elevated rib ; wrists with 

 one tooth. 



Sp. 1. Depuralor. The clypeus and shell on each Depurator. 

 side, with five nearly equal teeth y the wrists internal- 

 ly with a sharp spine ; shell Avith oblique granulated 

 lines; front with three teeth, middle one rather longest ; 

 hands above with one spine. 



Inhabits the European ocean. It is found on all the 

 shores of Great Britain, inhabiting water of twenty fa- 

 thoms. It is well known to the fishermen under the 

 name of flying crab, and is supposed by them (though 

 erroneously) to destroy oysters, by insinuating its flat- 

 tened hinder foot into the shell, when the animal opens 

 for food. 



Porlunus depuralor of Fabricius ; Cancer depurai 'or of 

 Linne. 



Sp. 8. Lividus. The clypeus with three teeth, mid- Lividus. 

 die one rather longest; shell on each side with five 

 nearly equal teeth; hands above with one tooth; wrists 

 internally with a sharp spine ; shell smooth, and more 

 depressed than in Depurator . 



A single specimen was taken by Mr Leach at New- 

 haven, since which time he has seen another in the col- 

 lection of Mr Montagu. The eyes are smaller, and the 

 antennae are shorter, than in Portunus depurator. 



Portunus lividus, Leach's MSS. 



Sp. 9- Marmoreus. Shell convex and smooth, with Marmt»« 

 very obsolete granulations ; front with three equal reus, 

 teeth, sides with five ; hands smooth ; wrists with one 

 sharp tooth within. 



Cancer pinnatus marmoreus, Montagu's MSS. 



Portunus marmoreus, Leach ; Malacost. Brit. ; Por- 

 tunus, Tab. A. 



The shell, when alive, most beautifully marbled with 

 4 



