PART 1 GARTH : PACIFIC OXYRHYNCHA 337 



2.7 mm, height of palm 2.6 mm, ambulatory legs 8.8, 7.6, 6.7, and 4.9 

 mm, respectively. Largest specimen, a female: length 15.4 mm, width 

 20.0 mm, cheliped 10.5 mm. 



Color in life: Dorsal surface of carapace dull yellow orange with 

 numerous indistinct darker small spots. Chelipeds as carapace, finger tips 

 white. Ambulatory legs white with but little color. Ventral side pale 

 gray with light touches of dull orange. (Petersen, of a Gulf of California 

 specimen) 



Habitat: Fine gray sand; rock, Albatross. (Rathbun) Sandy bottom 

 with weed, Zaca. (Crane) Rock, frequently covered with red algae, and 

 accompanied by sand or shell, Velero III (Garth, of Galapagos speci- 

 mens). For the 21 mainland stations for which data on bottom type are 

 available, the primary breakdown is as follows: sand 9, rock 7, mud 3, 

 organic (coral and nullipore) 2. A secondary breakdown shows shell and 

 nullipore frequently present with the sand, and sand and nullipore some- 

 times present with the rock. As in the case of Lissa tuberosa, L. auri- 

 villiusi appears to occur in mud only when diluted with sand or shell. 



Specimens from Costa Rica, invariably females, show parasitism by 

 Sacculina or other rhizocephalan parasite. Bryozoa are recorded as en- 

 crusting forms on Gulf of California and Galapagos Islands specimens. 



Depth: Mainland specimens from 2 to 35 fathoms; Galapagos speci- 

 mens to 70 fathoms. 



Size and sex: The Hancock series from the mainland contains males 

 of from 5.8 to 13.7 mm and females of from 4.5 to 12.2 mm (ovigerous 

 females from 7.7 to 12.2 mm). Three Gulf of California females, non- 

 ovigerous, run from 12.8 to 15.4 mm. These represent a giant race and 

 should not be compared with those taken outside the Gulf. Unfortunately 

 there are no comparable males. 



Breeding: Ovigerous females were taken by the Velero III off 

 southern Mexico in March and off Panama and Ecuador in February. 



Remarks: The range of the species is extended northward to Hughes 

 Point, Lower California, and to Puerto Refugio, Angel de la Guarda 

 Island, in the Gulf of California, and southward to La Libertad, Ecua- 

 dor. With the inclusion of the Galapagos Islands specimens, previously 

 reported (Rathbun, 1902b; Garth, 1946), the limits broadly define the 

 Panamic province. 



