MUSEUM OF COMPARATIVE ZOOLOGY. 159 



of the branchial region the two kinds of granules are found together. In 

 the median line there are three or four short blunt spines on the posterior 

 part of the gastric and the cardiac regions, the posterior one of which is 

 rather remote from the others, and much larger than tlfey, nearly as 

 large as the median posterior spine. There is a strong, triangular tooth, 

 pointing forward, on the subhepatic region, and a smaller tooth at the an- 

 terior extremity of the branchial region on the antero-lateral margin. On 

 the postero-lateral margin there is also a small tooth, or short spine. The 

 three posterior spines occupy the usual position (as in Persephona, Myra, 

 etc.), and are short. The outer maxillipeds are granulated, like the upper 

 surface of the carapax, and somewhat setose, the seta? arising between the 

 granules. The fourth, fifth, and sixth joints of the abdomen are soldered 

 together ; the surface is smooth and glossy about the middle, but there is 

 a transverse tuberculated ridge on the fourth joint, and the sixth joint is 

 sparsely granulated. 



Of the male sex I have but one half-grown example. The carapax is 

 rather broader and more depressed than in the female, and the granules 

 are smaller, less numerous, and more scattered. The posterior spines are 

 longer. The sternum and abdomen are evenly covered with minute, de- 

 pressed, crowded granules. 



Dimensions of a female specimen : Length of carapax, spine included, 

 0.70; breadth, 0.61; length of meros-joint of cheliped, 0.42; length of 

 hand, 0.65 inch. In the young male the length of the carapax is 0.39; 

 breadth, 0.65 inch. 



Lat. 24° N. Long., 83° W., January 22, 1868. Cast No. 3. 16 fathoms. 

 Off Carysfort Reef, March 21, 1869. Cast No. 8. 35 " 



"West of Tortugas, January 16, 1869. Cast No. 8. 37 " 



Subfamily EBALIINAE. 



The genera Ebalia, Nurda, Lithadia, Oreophorus, Spelaeophorus, etc., 

 appear to form a natural group, to which the name Ebaliinae may be 

 applied. 



Lithadia cadaverosa nov. sp. 

 The following description is that of a female, no males having occurred : 

 Carapax broad, somewhat octagonal in shape, very little produced poste- 

 riorly, and very strongly convex ; the branchial regions being more swollen 

 than in any of the other known species of the genus, and occupying by far 

 the greater portion of the carapax. These regions and the other protu- 

 berant parts of the carapax are more or less covered with depressed, often 

 confluent granules, arranged in lines or groups with depressed spaces in- 

 tervening, giving to the surface an eroded or vermiculated appearance. 



