PKN.EUS. CRUSTACEA. 165 



and longer than the body, and the peduncle with squamiform 

 teeth ; exterior feet-jaws long, the two first joints furnished 

 with stiff hairs and small spines on the internal side ; body ob- 

 long, subcylindrical, and the shell with a projecting beak; tail 

 terminated by a fan-shaped fin, the lateral pieces divided in 

 two ; six anterior legs didactyle, the first pair very long and 

 thick, with the hand more or less tuberculous and spinous. 

 A. marinus, Fab. The Lobster. (C. gammarus, Lin.) Shell ter- 

 minated anteriorly by a rostrum tridentate on each side ; forceps 

 very large, unequal ; the one oval,, with strong and blunt teeth, 

 the other smaller, oblong, and serrated ; margins of the segments 

 of the abdomen obtuse ; caudal fin rounded. 1 to 1^ foot long. 

 Inhabits rocky shores of Britain, &c. Pen. Brit. Zoo/, iv. pi. 11. 

 The Lobster is found on all the rocky shores of Britain, and taken in vast quan- 

 tities in many parts of Scotland for the London market. According to Pennant 

 60,000 or 70,000 were annually taken in the neighbourhood of Montrose alone. 

 Lobsters fear thunder, and are apt to cast their claws on a loud peal. They begin 

 to breed in spring, and continue breeding during the greater part of the summer. 

 They are extremely prolific. Baster counted 12,444 ova under the tail of one, be- 

 sides those that remained in the body unprotruded. They deposit the ova in the 

 sand, where they are soon hatched. Lobsters change their shell annually ; and in 

 both these and the crabs the claws which are injured or broken are speedily repro- 

 duced. They are very voracious animals, and feed on sea weeds and garbage of all 

 kinds. They are taken in baskets or traps formed like a mouse-trap and baited 

 with garbage. 



A.fluviatilis, Lat. (C. astacus, Lin.) The Craw-Fish. Shell ter- 

 minated by a rostrum unidentated laterally, and with a second 

 tooth on each side at the base ; forceps unequal, granulated, with 

 fine dentations on the internal side; lateral margins of the abdomen 

 pointed. European rivers. B. Penn. Brit. Zool. pi. 16, fig. 1. 

 The Craw Fish is esteemed as food, and their presence is said to be an index to the 



purity of the waters they inhabit. 



FAMILY VII. CARTDES. 



Intermediate antennae inserted above the lateral ones, projecting 

 and terminated by two or three filaments. 



Gen. 59- PENJSUS, Fab. 



Superior or intermediate antennae very short, bifid, on a very 

 large peduncle, deeply hollowed above to receive the eye ; 

 the exterior ones setaceous, very long, with a large scale at 

 their base ; exterior feet-jaws with five exserted joints, the 

 last obtuse ; the six anterior legs didactyle ; shell cylindri- 

 cal, terminated before by a pointed compressed rostrum. 



P. trisulcatus, Leach. Thorax trisulcated behind ; rostrum descend- 

 ing, multidentate above. British seas. Lin. Trans, xi, 347 



Gen. 60. STENOPUS, Lat. 



Middle or upper antennae terminated by two setaceous filaments, 

 longer than the body, and the exterior largest ; first three 



