238 Notes on North American Cmstaoea. 



crest on the base of the hand is continuous with it, and terminates 

 anteriorly in a tooth. Hand on the outer surface granulated, and 

 very sparsely low-tuberculated, with two or three longitudinal crests 

 armed with larger granules, near the base ; inferior margin denticu- 

 lated ; superior crest eight-toothed. Ambulatory feet as usual in the 

 genus. Length of carapax in a male, 1.57; breadth, 1.68 inch. In 

 young individuals the length and breadth are equal. 



It differs from C. granulosa De H. in its broader carapax, 

 and in having teeth on the exterior margin of the crest of the 

 meros and hand in the chelipeds. These teeth are not spini- 

 form as in G. cristata {s. dentata) Brulle. 



Found in great abundance at Cape St. Lucas, by Mr. 

 Xantus. 



LEUCOSOIDEA. 

 liithadia cariosa, nov. sp. 



Body and feet everywhere tuberculated or granulated above and 

 below. Carapax convex, subrhomboidal, with the anterior and pos- 

 terior angles truncated, and the lateral angles obtuse, but not at all 

 truncated. A small tooth on the postero-lateral margin, sepa- 

 rated by a deep sinus from the posterior extremity or intestinal region, 

 which is bilobate. The hepatic region projects scarcely at all beyond 

 the antero-lateral margin, but is seen in a side view to project beneath, 

 forming a triangular tooth on the inferior surface. On the upper sur- 

 face, the cardiac, and the inner lobules of the branchial region are 

 strongly protuberant. The front is also prominently elevated, and con- 

 nected with the middle protuberances of the carapax by a narrow 

 longitudinal ridge traversing the gastric region, which ridge, together 

 with the frontal region, is much smoother than the rest of the surface. 

 On either side of this ridge there is a deep and rather broad excavation 

 of a darker color than the protuberant j)arts, which extends laterally 

 over the anterior part of the branchial region, but is nearly divided in 

 two by the slightly prominent hepatic region, which projects inward 

 from the antero-lateral margin, with an arcuated inner edge armed with 



