DEC A POD A. CANCERIDM. 



BRACHYURA. 



GENUS XANTHO, Leach. 



Cancer, Montagu, Ilerbst. 



Xantho, Leach, Edwards. 



Generic Character. — External antenncB very short, the basal 

 joint longer than it is broad, in contact with the front only at its 

 anterior internal angle ; the moveable portion inserted at the inner 

 canthus of the orbit ; the second joint considerably larger than the 

 succeeding ones. Internal antennae placed obliquely immediately 

 under the front. External jjedipalps with the third joint quad- 

 rate, the inner anterior angle truncate and slightly emarginate. 

 Carapace very broad, slightly convex from before backwards ; the 

 latero-anterior margins with the front forming a semi-ellipsis ; the 

 latero-posterior margin nearly straight ; front projecting, divided by 

 a slight fissure ; orbits, with a fissure beneath, at the external 

 angle. Anterior legs very large, nearly equal, the fingers pointed. 

 The posterior pairs short, compressed ; the terminal joint very 

 short. Abdomen, in the male, five-jointed ; in tlie female, seven- 

 iointed. 



