THE CRUSTACEA OF NEW JERSEY. 409 



of dactylus pink, rest porcelain-white, and chelipeds below, also 

 carpal tooth, yellow. Feet all paler below, like lower surface of 

 body. Length of carapace 30 mm., width 46 mm. 



Remarks. — A tropical and subtropical species, ranging from 

 New York to Brazil and Bermuda. I have not seen any recent 

 specimens. Two dried examples in the Academy of Natural 

 Sciences of Philadelphia, described above, and labeled "New 

 Jersey," were recived from Thomas Say. It is upon this data 

 that I venture to include the species within our limits. De Kay 

 also mentions it from New Jersey, possibly on Say's material. 



Young examples, from Absecon, are also likely this species. 



Family PORTUNID^. 

 The Swimming Crabs. 



Carapace depressed, moderately transverse, usually widest at 

 least antero-lateral marginal spine. Usually from five to nine 

 antero-lateral spines or teeth. Front horizontal. Orbits and 

 eye-stalks of moderate length. Last trunk legs usually adapted 

 for swimming, with terminal joint ovate, flatly expanded. 



These crabs, with a single exception, have the last pair of 

 legs formed as swimming-paddles. They include several very 

 common and valued species in a commercial way. Some are 

 also palagic, or with wide distribution. 



About seven genera represented in Eastern North America. 



Key to the genera. 



a. Last pair of legs narrow, with lanceolate dactyls. carcinides. 

 aa. Last pair of legs broad, formed as swimming-paddles. 



b. Carapace decidedly transverse ; antero-lateral margins cut into nine 

 teeth. 



c. No longitudinal ridge on palate. aren.=Eus. 



cc. A longitudinal ridge on palate. callinectes. 



bb. Carapace not very broad ; antero-lateral edges cut into fine teeth. 



OVALIPES. 



