378 BULLETIN 129, UNITED STATES NATIONAL MUSEUM 



ANAPTYCHUS CORNUTUS Stimpson 



Plate 134, figs. 4 and 5; plate 254, fig. 1 



Anaptychus cornutus Stimpson, Ann. Lye. Nat. Hist. New York, vol. 7, 1860 

 p. 184 [56], pi. 2, figs. 1, la, lb (type-locality, Pinacate Bay, near Guay- 

 mas, Gulf of California; type, male, not extant). — A. Milne Edwards, 

 Crust. R6g. Mex., 1875, p. 67, pi. 19, figs. 1-16. — Kingsley, Proc. Boston 

 Soc. Nat. Hist., vol. 20, 1879, p. 146. 



Ala spinosa Lockington, Proc. California Acad. Sci., vol. 7, 1876 (1877), 

 p. 66 [4] (type-localities. La Paz, San Jos^ Island and Port Escondido, all 

 in Gulf of California; types not extant). 



Miirax trigonopus Cano, Boll. Soc. Nat. Napoli, ser. 1, vol. 3, 1889, p. 183, 

 pi. 7, fig. 8 (type-locality, Panama; type in Naples Mus.?). 



Mithrax trigonopus Rathbun, Proc. U. S. Nat. Mus., vol. 38, 1910, p. 575. 



Diagnosis. — Carapace broader than long. Antero-lateral margin 

 a thin, tridentate crest. Rostral and antennal spines similar and 

 subequal. Chelipeds and legs cristate. 



Fig. 122. — ANAPTTCHUS CORNUTUS, MALE, TYPE. 0. ANTENNAL REGION, VENTRAL VIEW. 6. MAXILLIPED. 



(After Stimpson.) 



Description. — Carapace covered with minute tufts of very short 

 setae. Upper surface nearly level, but the gastric, cardiac and 

 inner part of branchial region slightly protuberant; nine or ten low 

 tubercles on the gastric region. Antero-lateral margin with three 

 large triangular sublaminiform teeth behind the orbit, separated 

 from each other by regularly curved sinuses. Posterior margin with 

 a crest interrupted on each side; the middle portion being arcuated, 

 six-lobed and fringed with pencils of stout, longish setae. Rostrum 

 from one-fourth to one-fifth as long as remainder of carapace, and 

 cleft nearly to its base; horns acute. 



Chelipeds a little longer than the first pair of ambulatory legs, but 

 scarcely thicker; merus with five or six blunt, somewhat laminiform 

 spines; outer surface of carpus with a laminiform, longitudinal crest 

 through the middle and tubercles on each side; hand unarmed, 

 minutely granulate; fingers narrowly gaping, crenulate within, tips 

 not spoon-shaped within. Inferior surface covered with short, stout 



