126 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 24 



large proximal tubercle; pollex with an elongate tubercle on proximal 

 half of cutting edge, its tip long and sharply incurved; fingers gaping, 

 especially in males, but usually crossing at tips. Pollex of minor cheliped 

 with long incurving tip as in major cheliped; fingers meeting entire 

 length, crossing at tips. Gape in both chelipeds with a trace of pub- 

 escence. 



Merus of walking legs with an anterior fringe of plumose hairs; a 

 similar fringe on the distal half or two-thirds of carpus; hairs also on 

 dorsal surface of carpus near articulation with propodus; propodus and 

 dactylui covered with plumose hairs and a few scattered, non-plumose 

 setae. 



Abdomen punctate, telson with seven plates. A pair of pleopods in 

 male. 



Jariations: The crests on the dorsal surface of the carpus are some- 

 times quite high and at other times low, but always more distinct than 

 in Neopisosoma mexicanum ; the crests may be smooth or covered with 

 flattened granules. In addition to the four or five teeth usually present 

 on the anterior margin of the carpus, a small distal tooth may be present 

 between the last full-sized tooth and the one formed by the projec- 

 tion of the anterodistal angle. In one specimen examined, the two prox- 

 imal teeth were coalesced. 



Measurements: Holotype male: length 5.4 mm, width 5.4 mm. Para- 

 types: males, 3.6 to 6.4 mm; ovigerous females, 4.5 to 5.3 mm. 



Color: All specimens were faded in alcohol to a pale buff. The hairs 

 on the dorsal surface of the manus were straw-colored, but the pile was 

 filled with silt in most cases and consequently appeared black. 



Ecology : All specimens were taken in the littoral, presumably under 

 stones, with the exception of the three from La Libertad, Ecuador, 

 which were collected by diving in 2 fathoms. 



All female specimens were ovigerous, and were collected in Decem- 

 ber, January, and February. 



Relationships: Neopisosoma bicapillatum has two close relatives, 

 N. mexicanum (Streets) and N. curacaoense (Schmitt), 1924. N. 

 mexicanum usually has but three carpal teeth, which occupy no more 

 than two-thirds of the anterior margin; the crests on the carpus are 

 always low, sometimes obsolescent; and long plumose hairs are present 

 on the manus of the minor cheliped only. N. bicapillatum is closer to 

 the Caribbean species N. curacaoense, which has very similar carpal crests 

 and teeth. In A'^. curacaoense the long hairs are not invariably 



