542 



BULLETIN 129, UNITED STATES NATIONAL MUSEUM 



angles obtuse. Rostrum 

 rather prominent and 

 faintly tridentate at ex- 

 tremity; median tooth 

 smallest and most prom- 

 inent. External angle 

 of orbit not prominent: 

 Eye large, with a very 

 minute tubercle at sum- 

 mit. Basal joint of ex- 

 ternal antennae about 

 as long as next joint. 

 Subhepatic region less 

 concave than in typicus 

 and without supple- 

 mentary ridge. Exter- 

 nal maxillipeds and af- 

 ferent channels nearly 

 as in S. typicus, but with 

 the ridges less strongly 

 tuberculated and the 

 outer angle of merus less 

 acutely prominent. 

 Sternum between bases 

 of chelipeds convex on 

 either side, and nearly 

 smooth. Chelipeds very 

 long and slender; edges 

 denticulated, surfaces 

 smooth and polished ; 

 merus with about 13 

 denticles on either edge, 

 the third denticle from 

 distal end of anterior 

 edge being larger than 

 the others; hand with 

 11 or 12 sharp, forward- 

 curving teeth on supe- 

 rior edge, the terminal 

 tooth above finger spini- 

 form and considerably 

 longer than the others; 

 outer edge of hand with 

 11 to 13 obtuse, less 

 prominent, minutely 



