114 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



with two median tubercles, the anterior the smaller; hepatic region not 

 prominent, bearing a marginal tubercle; pterygostomian ridge with a 

 tubercle; postorbital tubercle small, midway between orbit and buccal 

 cavity. Rostrum a triangulate, acuminate spine nearly as long as the 

 remainder of carapace, posteriorly hollow beneath, anteriorly upturned. 

 Orbital arch thickened. Basal antennal article partially visible from 

 above, a tooth at its anteroexternal angle, from this a convex ridge 

 extending backward and inward ; flagellum visible at sides of rostrum. 

 Surface of maxillipeds spinulous. 



Inner surface of chelipeds spinulous; outer margin of merus ir- 

 regularly lobed ; a spine at distal end above and on inner side ; carpus 

 with a stout external, and also anterior, spine. Palm dilated, ringers 

 gaping ; in the gape a truncate and a spiniform tooth on the dactyl and a 

 triangular tooth on the immovable finger. First pair of ambulatory legs 

 about one and two-thirds, second pair one and one-third, times the total 

 length of the carapace; fourth pair not so long as the carapace. Propodus 

 slightly thickened distally, about one and two-thirds times the length 

 of the dactylus in the first pair and one and a half times the length of 

 the dactylus in the remaining pairs. 



Sternum having very slight depressions between the segments, and 

 two stout cylindrical spines tipped with a granule at the base of the 

 chelipeds. A tubercle on first abdominal segment. (Rathbun, 1925, 

 modified) 



Material examined: A total of 54 specimens from 23 stations, all in 

 the Gulf of California. (See Table 18) These are distributed from Rocky 

 Point, Sonora, to La Paz Bay, Gulf of California, and from shore to 

 30 fathoms. In addition, Patos Island Anchorage, Gulf of California, 

 Mexico, April 23, 1921, 4.5 fathoms, Fred Baker, collector, 1 female 

 (of 2 males and 2 females identified by Mary J. Rathbun), C. A. S. 



Measurements: Largest specimen, a male, rostrum broken near tip: 

 length 25.3 mm, width 16.6 mm, cheliped 34.2 mm, chela 16.3 mm, 

 dactyl 8.3 mm, first ambulatory leg 51.6 mm, propodus 10.6 mm, 

 dactylus 6.4 mm, remaining legs detached and fragmentary. Female: 

 length 18.3 mm, width 10.0 mm, rostrum 6.8 mm. Largest complete 

 specimen, male: length 20.6 mm, width 9.5 mm, rostrum 9.3 mm, width 

 1.8 mm, cheliped 15.7 mm, chela 6.9 mm, dactyl 3.8 mm, height of palm 

 2.0 mm, ambulatory legs 31.3, 27.5, 23.6, and 19.8 mm, respectively. 



Color in life: Not recorded. The following notes on specimens in 

 alcohol are taken from Crane (1937, p. 52): Uniformly yellow buff, 

 more or less speckled with black in the sulci between regions and on the 



