Genus Callinectes. 575 



mittent organs, are very striking characteristics. It is 

 nearly as large as hastatus. 



Found at Key West, Florida, by J. E. Mills, and at the 

 Island of Ilayti, by A. Hilchcnbach. 



There is a small specimen of a sterile female from As- 

 pinwall in the museum of the Smithsonian Institution, 

 which apparently belongs to a different species from any 

 of those that I have described. The carapax is quite broad 

 and convex, and in its general features very much resem- 

 bles that of tumidus. But the hepatic region is smooth — 

 wholly destitute of granulation. The front is armed with 

 four teeth which are almost equal in size. The teeth of 

 the antero-latcral border are very broad, with convex sides, 

 and with their bases in close contact. Sternum slightly 

 convex. Chelipeds not quite so stout as in tumidus. 



CALLINECTES DIACANTHUS Ordway. 



Lvpa dicantha Dana, U. S. Expl. Exped., Crust, i. 272. 



Through the liberality of the Smithsonian Institution, 

 I have been able to examine the specimen described by 

 Dana, from Rio Janeiro. As it is only a single dried spe- 

 cimen, it is rather difficult to make a thorough comparison, 

 but I have not the least doubt that it is entirely distinct 

 from any of the more northern species. It is the most 

 closely allied to ornatus. But the carapax is more convex, 

 the branchial regions more swollen, and the cardiac and 

 intra-medial regions do not exhibit the narrow form char- 

 acteristic of ornatus; in fact, the carapax bears more re- 

 semblance to that of larvatiis. The teeth of the front re- 

 semble those of ornatus, but they are comparatively quite 

 sharp. Sub-median tooth of front quite slender. Spine 

 on the interior angle of the lower margin of the orbit com- 

 paratively sharp. The teeth of the antero-lateral border are 

 very nearly of the same size and shape as in ornatus, but 

 are rather more separated at their bases. 



