110 Rathbun — Neiv Crabs from Gulf of Siam. 



lateral angle. Orbits invisible from above; eyes pigmented. Last two 

 segments of endognatb mitten-shaped, dactylus small, attached half-way 

 back on propodus, and reaching its terminal fifth. Chelipeds stout, palm 

 widening distally, pollex wider at base than dactylus. I-<egs, third long- 

 est, second next, first and fourth subequal; dactyli of third and fourth 

 pairs longest, equal. 



Pinnotheres quadratus sp. nov. 



Type. — Q , Koh Chang, one fathom, coral. 



Dimensions. — Length, 5.2 mm. ; breadth, 5.3 mm. 



Near P. palaensis Biirger. Carapace subquadrate, with rounded cor- 

 ners. Orbits ventral, eyes pigmented. Propodus of maxilliped large, 

 spatulate, overreaching inner angle of merus; dactylus small, linear, 

 scarcely visible when maxillipeds are folded in place. Cheliped stout, 

 widening distally, more than twice as long as high, and twice as long as 

 fingers; a large tooth near base of dactylus fits between two smaller teeth 

 on pollex. Legs, third longest, fourth next, second next; third and fourth 

 dactyli longest, subequal, first and second subequal. 



Pinnotheres nigrans sp. nov. 



Type. — 9 ) Koh Lan. 



Dimensions. — Length, 6.8 mm.; width, 8.3 mm. 



Allied to P. latus Biirger. Carapace very high in the middle ; anterior 

 margin advanced at middle; orbits invisible in dorsal view; cornese 

 black. Dactylus of endognatb does not reach end of propodus, which 

 tapers toward the end. Cheliped not much stouter than legs, palm widest 

 at distal end, margins nearly straight, 1}^ times as long as fingers. Legs 

 nearly of a length, third longest, second and fourth next, subequal ; dactyli 

 of third and fourth pairs longest, equal, twice as long as the others. 

 Pinnotheres kamensis sp. nov. 



Type. — c?, west of Koh Kam, 5 fathoms. 



Dimensions. — Length, 1.4 mm. ; width, L5 mm. 



Carapace ovate, an antero-lateral angle; surface coarsely punctate; 

 front strongly advanced, bilobed ; eyes large, orbits in margin of cara- 

 pace; cornepe black. Inner margin of merus of endognatb angled; 

 propodus long and narrow ; dactylus inserted behind middle of propodus, 

 and not reaching end of same. Chelipeds short and stout, fingers gaping 

 widely. Legs broad, first 3 pairs subequal, last pair smaller; same is true 

 of the strongly curved dactyli. 



Pinnotheres kutensis sp. nov. 



Type. — cJ*, south of Koh Kut, 17-20 fathoms, nuul. 



Dimensions. — Length, 1.1 mm.; width, 1.02 mm. 



Carapace oblong-hexagonal, transparent; front advanced, subtruncate, 

 eyes large, projecting beyond carapace. Palpus of endognatb reaches a 

 little beyond angle of merus; propodus short, broad, with dactylus articu- 

 lating near its middle and overreaching it. Hands inflated, fingers 

 slender, gaping. Legs, second longest, third next, first next; dactyli, 

 fourth shorte.st, others subequal. 



