230 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



Measurements: Largest specimen, male: length 16.5 mm, hepatic 

 width 12.8 mm, branchial width 12.85 mm, rostrum 4.4 mm, width 2.6 

 mm, cheliped 16.1 mm, chela 7.0 mm, manus 4.6 mm, dactyl 2.8 mm, 

 height of palm 3.2 mm, walking legs 16.6, 13.4, 11.5, and 9.8 mm. 



Color in life: Creamy to ochraceous yellow, the chelipeds and ventral 

 surface sometimes spotted or blotched with brown. (Crane) Uniformly 

 tawny olive except for scattered blotches of white on cardiac and gastric 

 portion of carapace and around joints of ambulatory legs. Ventral side 

 greenish white with a strong lavender tinge; maxillipeds distinctly 

 lavender. Pterygostomian region light tawny olive. (Petersen) 



Habitat: Found at low tide under stones and in coral. (Lockington) 

 On sandy bottom with weed and stones. (Crane) Associated with the 

 hatchet clam Pinna at Concepcion. (Steinbeck and Ricketts) In the 12 

 instances for which data on bottom type are available, Hancock expedi- 

 tions specimens were recovered from a substratum of rock in 6 cases, 

 of sand in 2 cases, of coral or coralline in 3 cases, and of algae in one case. 



Depth: Shore to 17 fathoms. Extreme tidal fluctuations in the north- 

 ern part of the Gulf of California expose rich and varied algal fields such 

 as occur at Turner's Island, off the south end of Tiburon Island, and 

 on the reef at Puerto Refugio, Angel de la Guarda Island, to depths 

 of between 18 and 24 feet. 



Size and sex: Males of the present series measure 5.5 to 16.5 mm, 

 females 5.3 to 15.8 mm, ovigerous females 10.4 to 15.8 mm. Largest 

 specimen on record is the 21 x 16 mm male from Patos Anchorage 

 (C.A.S.) reported by Rathbun (1924c). 



Breeding: Ovigerous females were encountered by the Velero III 

 in the Gulf of California in March, by E. Yale Dawson while 

 diving near Guaymas, Sonora, in May, and again at La Paz Bay in 

 November, and by Wm. N. Smith II at Tiburon Island in June. Crane 

 (1937, p. 57) reports 7 of 9 females taken at Santa Inez Bay as carrying 

 eggs in April. 



Remarks: Hancock specimens exhibit even greater diversification than 

 the remarkable series illustrated by Crane {op. cit., pi. 2, fig. 7), since the 

 specimens collected by the Velero III come from a variety of localities, 

 whereas those of the Zaca were all obtained at Santa Inez Bay. In at 

 least two of the specimens examined, an 11.8 mm female from Con- 

 cepcion Bay, station 683-37, and a 7.6 mm female from Agua Verde 

 Bay, station 1104-40, both in the Gulf of California, the configuration 

 of the carapace is clearly that given for Epialtus crenulatus (Rathbun, 

 1925, text-fig. 53f). It will be noted that the characters which separate 



