Notes on North American Crustacea. 215 



lateral margin. Three projecting teeth on the inferior margin of the 

 orbit, the inner one very large, flattened on its outer surface. External 

 antennae long. Fingers and infero-exterior surface of hands smooth and 

 naked ; the naked part sharply defined by an oblique line on the 

 outer surfcxce. Length of carapax in a male, 0.25 ; breadth, 0.36 inch. 



Inhabits St. Thomas ; A. H. Kiise. 



PiluinniBs ceratopws, nov. sp. 



Body above clothed with very short tufts of pubescence, somewhat 

 irregularly arranged, leaving many open spaces ; feet much more thickly 

 covered, with a longer hairy coat. Carapax much less convex than 

 usual, and even flattened posteriorly, but anteriorly moderately sloping 

 toward the margins. Regions sufficiently distinct, but neither lobulated 

 nor tuberculatecl, A transverse ridge on the frontal region, interrupted 

 at the middle. Surface naked along the anterior margins, which are 

 obtuse and thickened. Three long, acute spines on the antero-lateral 

 margin. Front nearly horizontal, very little projecting, and strongly 

 sinuated at the middle. Superior margin of the orbit unarmed, but 

 fissured at the middle ; outer angle tuberculiform, projecting laterally. 

 Inferior margin of the orbit deeply bi-lobate ; lobes large, triangular, 

 projecting ; external hiatus well-marked, and armed with a tooth at the 

 bottom. Chelipeds above, and externally, covered with short spines ; 

 anterior half of palm of hand naked, and of a bright red or purplish 

 color. Ambulatory feet compressed, densely hairy ; meros with a spine 

 at the superior extremity ; carpus with a large, smooth, procumbent, 

 horn-like process lying upon its upper side, in front of which are three 

 spines along the anterior margin ; dactylus of the usual length. Length 

 of carapax in a male, 0.3 ; breadth, excluding the spines, 0.4 inch. 



This pretty little species, very peculiar in the armature of its 

 ambulatory feet, was found at Key Biscayne, Fla., by the late 

 Gustavus Wurdemann, Esq. 



AFBIL, 1860. ;|^5 Amn. Lto. Nat. Hist. Vol. VII. 



