448 BULLETIN 129^ UNITED STATES NATIONAL MUSEUM 



West Florida; 19 fathoms; William Stimpson; 1 young male, soft 

 shell, holotype (1989, M. C. Z.). 



Florida; 1 large female (2107, M. C. Z.). 



Genus STENOCIONOPS (Leach MS.) Desmarest 



Sienocionops (Leach MS.) Desmarest, Diet. Sei. Nat., vol. 28, 1823, 

 p. 266; Cousid. Gen. Crust., 1825, p. 153; type, Maia taurus Lamarck, 

 Latreille, 1818 = Cancer furcatus Olivier, 1791. — Gu^rin, Encyc. Meth., 

 Entom., vol. 10, 1825, p. 484. 



Pericera Latreille, Encyc. Meth., Entom., vol. 10, 1825, p. 699; type. 

 Cancer fuscatus [slip for furcatus] Olivier; Cuvier's Regne Anim., ed. 2, 

 vol. 4, 1829, p. 58 (subgenus). — Rathbun, Proc. U. S. Nat. Mus., vol. 15, 

 1892, p. 243, and synonymy. 



Carapace subpyriform, rather convex, with dorsal surface uneven, 

 tuberculated or spinous; lateral margins armed with a series of long 

 spines; preocular spine well developed. Rostrum composed of two 

 strong spines which are not deflexed and are divergent from base; 

 orbits tubular, not strongly projecting; eyes small, retractile within 

 orbits. Basal antennal joint considerably enlarged, armed with one 

 or two small distal spines or tubercles not visible in a dorsal view. 

 The merus of outer maxillipeds with distal margin truncate, antero- 

 internal angle emarginate, antero-external angle rounded or subacute. 

 Chelipeds in adult male well developed; palm elongate and sub- 

 cylindrical or somewhat compressed, not dilated or enlarged; fingers 

 either without any or with a moderate intermarginal hiatus at the 

 base when closed. Ambulatory legs moderately elongated, with 

 joints subcylindrical, without spines; dactyli nearly straight. Ab- 

 domen in male distinctly seven-jointed. 



Distributed on the east coast of America from Cape Hatteras, North 

 Carolina, to Rio de Janeiro, Brazil; on the west coast from Lower 

 California to Galapagos Islands. West Africa (Miers), 



KEY TO THE SPECIES OF THE GENUS STENOCIONOPS 



A'. Hepatic region not enlarged nor produced be5^ond the general outline of the 

 carapace; armed with not more than one large spine. 

 B^ Rostral horns divergent throughout or at least for their basal half. 

 CK Marginal spines behind orbit more than three. 



D^ Dorsum almost unarmed except for a median intestinal spine. 



furcata, p. 449. 

 D^. Dorsum armed with spines. 



E'. Fewer than eight median spines furcata coelata, p. 450. 



E2. Eight median spines ovata, p. 459. 



C^. Marginal spines behind orbit three. 



D'. Carapace widest between tips of anterior branchial spines. 



spinimana, young, p. 457. 

 D^. Carapace more triangular, usually widest between tips of posterior 



branchial spines triangulata, p. 461. 



B^. Rostral horns curved, convex to each other, contiguous in the middle. 



contigua, p. 451. 



