72 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 5 



its outer border makes a broadly concave arc with the outer border of 

 the ischium. A granular ridge runs from the anteroexternal angle of 

 the buccal cavity to the base of the cheliped. 



Chelipeds short, heavy, and strikingly disproportionate; the meinis 

 of each widest at its mid-point, with two serrate denticles on its inner 

 margin and a clear row of beaded tubercles running the length of its 

 inferior surface; carpus of each with a continuation of this granular 

 ridge on the under side and three additional lines of granules on the 

 superior surface; manus of the large claw with a high superior crest 

 faintly angled at its mid-point, a median crest on the inner surface of the 

 palm more sharply angled, and an outer row of bead granules similar 

 to those on the carpus and merus; manus widening distally, greatest 

 height one-half times the length; dactyl strongly curving downward, 

 provided with spinulous ridges, and meeting pollex with a wide gape; 

 immovable finger curving slightly upward, not constricted at base. 

 Minor chela with a single tooth at mid-point of superior crest, widening 

 little distally, its lower margin straight; fingers closing without a gape, 

 tips crossing. 



Segments 3-5 of male abdomen fused ; abdomen narrowest at base of 

 sixth segment, seventh segment triangular. 



Color in alcohol: The specimen still retains a purplish-brown area 

 embracing the rostrum and the anterior portion of the carapace. Against 

 this background a light line runs inward from the base of each denticle 

 of the lateral margins. 



Remarks: This species is the Pacific analogue of Heterocrypta 

 granulata (Gibbes) (1849), from which it may be distinguished by the 

 straighter posterior margin concealing the fourth pair of walking legs 

 and the consequently more evident angle of the posterior margin at the 

 branchial ridge. It also differs from granulata by the depressed, non- 

 granulate cardiac region, the more elongate front, the more prominent 

 serrate teeth on the merus and manus of the cheliped, the greater height 

 of the large claw in proportion to its length, and the upturned, rather 

 than deflexed, immovable fingers. The lateral and posterior protuber- 

 ances of the sixth abdominal segment of the male in granulata are 

 wanting. 



The discovery of this short-armed species at Port Utria, Colombia, 

 fills a gap in the genus as represented in the Pacific. The other species, 

 Heterocrypta macrobrachia Stimpson (1871) and H. occidentalis 

 (Dana) (1854), are both long-armed species. The new species is more 



