292 BULLETIN 120, UNITED STATES NATIONAL MUSEUM 



Genus LEPTECES Rathbun 



Lepteces Rathbun, Proc. U. S. Nat. Mus., vol. 16, 1893, p. 83; type, L. 

 prnatus Rathbun. 



Carapace siibpyriforra or triangulate, slightly convex, tuberculate; 

 preocular spine present. Rostral spines divergent. Orbit with two 

 hiatuses above and one below. Antennae with a spine at antero- 

 external angle of basal segment, movable portion visible in dorsal 

 view at sides of rostrum. Outer maxilliped with antero-external 

 angle strongly produced and rounded, inner angle notched. Chelipeds 

 more slender than ambulatory legs; manus more slender than merus; 

 fingers very short, meeting when closed. Ambulatory legs spinous, 

 diminishing rapidly in length from first to fourth leg. 



Contains only one species. 



LEPTECES ORNATUS Rathbun 



Plate 244, fig. 2 



Lepteces ornatus Rathbun, Proc. U. S. Nat. Mus., vol. 16, 1893, p. 84, 

 pi. 6, fig. 1 (type-locality, off Arrowsmith Bank, Yucatan; holotype. Cat. 

 No. 9546, U.S.N.M.). 



Diagnosis. — Chelipeds filiform. Flat-topped mushroom tubercles 

 form a regular pattern on carapace. A lobe 

 between supraocular eave and exorbital tooth. 

 Description. — Entire surface except chelae 

 granulate. Carapace ornamented with tu- 

 bercles of two kinds; first and most conspicu- 

 ous, raised mushroom-like tubercles, each sur- 

 mounted by a flat, circular, granulate disk. 

 Tubercles of this sort with disks overlapping 

 surround cardiac region and outline inner 

 margin of branchial region; one on posterior 

 edge of gastric region, four follow postero- 

 lateral margin, two arranged transversely on 

 Fig. 98.-LEPTECES ornatus the intestinal region, while a line of four runs 

 (9546), MAXILLIPED, X 18 almost transversely across each hepatic region 

 and onto the gastric; many additional smaller tubercles of this sort. 

 The second variety of tubercle is smaller but higher, more like a 

 cylindrical spine, granulate and surmounted by a few long hairs; 

 four such tubercles on gastric region, two being median, six on bran- 

 chial region, two or three on cardiac region, three on posterior 

 margin. Entire surface between and beneath the tubercles is crowded 

 with stellar granules, varying in size. 



Rostral spines regularly tapering, divergent, with long hairs 

 especially on inner margins. Preocular spine strongly curved up- 

 ward (concave above), at an angle of about 45 degrees with rostrum, 

 acute, a few long hairs at tip. 



