198 BULLETIN 129, UNITED STATES NATIONAL MUSEUM - 



Genus LOXORHYNCHUS Stimpson 



Loxorynchiis Stimpson, Proc. Boston Soc. Nat. Hist., vol. 6, Feb., 1857, 



p. 84; type, L. grandis Stimpson. 

 Loxorhynchus Stimpson, Journ. Boston Soc. Nat. Hist., vol. 6, 1857, p. 451 



[10]; correction of Loxorynchiis. 



Carapace pyriform, tuberculate or spinous, and pubescent. Gastric 

 region large, convex. Hepatic region small, prominent, armed with 

 one or two stout spines. Rostrum bifid, more or less deflexed; horns 

 divergent. Orbits imperfect, interrupted above and below by a deep, 

 longitudinal sinus; ocular cavity subtubular. Eyes rather short, 

 retractile, not concealed. Preorbital tooth strong; postorbital tooth 

 acute, almost longitudinal; below it there is a smaller spine just out- 

 side the basal article of the antenna. TlTis article is broad, nearly 

 quadrate, armed at the outer apex with an acute spine extended 

 laterally; movable part of the antenna not concealed by the rostrum; 

 flagellum long. Epistome large. Pterygostomian region tuberculate. 



Ischium of external maxillipeds strongly produced and rounded at 

 the antero-internal angle; the same angle of the merus is subrec- 

 tangular, internal angle deeply notched for insertion of palpus. Cheli- 

 peds of adult male much enlarged, longer than next leg; fingers 

 gaping, extremities dentate, a large basal tooth on the dactylus. 

 Legs diminishing in length from the first to the fourth pair; subcylin- 

 drical; dactyli stoub, unarmed. Abdomen with seven separate 

 segments in both sexes. 



Inhabits the west coast of California and Lower California, Mexico. 



KEY TO THE SPECIES OF THE GENUS LOXORHYNCHUS 



A'. Carapace multispinous. Hepatic region armed with two large spines. Front 

 strongly deflexed grandis, p. 198. 



A2. Carapace covered chiefly with a few large bosses or tubercles, each tipped 

 with a spine. Hepatic region armed with one large spine. Front moder- 

 ately deflexed ...crispatus, p. 200. 



LOXORHYNCHUS GRANDIS Stimpson 



SHEEP CRAB; KELP CRAB 

 Plates 64 and 65 



Loxorynchus grandis Stimpson, Proc. Boston Soc. Nat. Hist., vol. 6, Feb., 



1857, p. 85 (type-locality, near San Francisco, California; holotype. Cat. 



No. 15376, U. S. N. M.); Ann. Lye. Nat. Hist. New York, vol. 7, 1859, 



p. 49. 

 Loxorhynchus grandis Stimpson, Journ. Boston Soc. Nat. Hist. vol. 6, 1857, 



p. 452 [12], pi. 20, fig. 1; pi. 22, fig. 1.— Holmes, Occas. Papers Calif. 



Acad. Sc'i., vol. 7, 1900, p. 29.— Rathbun, Proc. U. S. Nat. Mus., vol. 35, 



1908, p. 342, pis. 45, 46 and 47, fig. 1; fossil. 



Diagnosis. — Carapace multispinous. Two large hepatic spines. 

 Front strongly deflexed. Two tubercles on basal antennal segment. 

 Upper margin of manus of adult male less than twice its width. 



