26 CRUSTACEA. 



of the too great similarity between the latter and the word Portunus 

 already adopted. Here the shell is at least as long as it is broad 

 and almost cordate. All the tarsi of the feet, the claws excepted, 

 terminate in a small, semi-elliptical, elongated and pointed lamina ; 

 the index is strongly compressed. 



This division also comprises but a single species, the Cancer 

 latipes, Plancus, De Conchis minus notis III, 7, B, C, and 

 which has also been figured by Leach Malac. Brit., IV. There 

 are three teeth front, and on each lateral edge five(l). 

 From the swimmers we pass to those whose feet all terminate in a 

 point, or conical and sometimes compressed tarsus, but never form- 

 ing a fin properly so called. Those of them whose shell is tapering, 

 forming the arc of a circle before, and narrowed and truncated be- 

 hind, in which the claws of both sexes are alike, where the number 

 of the caudal segments is the same as in the Portuni, and which, 

 with the exception of the tarsi, almost completely resemble them, 

 will constitute our second section, that of the Arcuata. In the 



Cancer, Fabr. 



Or the Crab properly so called, the third joint of the external 

 foot-jaws is emarginated or marked with a sinus near the internal 

 and almost square extremity. The antennae scarcely extending be- 

 yond the front and composed of but few articulations, are flexed and 

 glabrous, or but slightly hairy. The hands are rounded and have 

 no appearance of a crest on the upper edge. 



The radical joint of the external antennae is, in some, much larger 

 than the following ones, and resembles a lamina; terminated by a sa- 

 lient and advanced tooth, closing inferiorly the internal corner of the 

 ocular cavities. The fossulae of the middle or internal antennae are 

 nearly longitudinal. Such is the 



C. pagurus, L.; Crabe poupart, Sec; Herbst., IX, 59. Shell 

 reddish, wide, plane, almost smooth above, with nine festoons 

 in each lateral margin, and three teeth in front. Its claws are 

 large, smooth, with black fingers studded internally with blunt 

 tubercles. It is sometimes a foot wide, and weighs five pounds. 

 Common on the Atlantic coast of France, but less abundant in 

 the Mediterranean. Its flesh is esteemed. Dr. Leach separates 

 it generically from the other Crabs: Malac. Brit., XVII, x. 

 In the others, the lower joints of the Antennae are cylindrical; al- 

 though somewhat larger, the first does not differ from the following 



(1) See the article Plat yuniquc, Encyc. Methodique. 



