COMPLETE HAIG : EASTERN PACIFIC PORCELLANIDAE 79 



tnerus Stimpson from Half Moon Bay, California, was also based on 

 specimens of P. manimaculis, as determined by the present writer who 

 saw the Half I\Ioon Bay material in the U. S. National Museum. 

 Schmitt's reference to "Lower California" as the southern extent of the 

 range of P. erio/nerus may also be based on P. manimaculis, for P. 

 erionierus is not known to occur that far south. It is believed that Hil- 

 ton's (1916) reference to P. erioriierus from Laguna Beach, and Ricketts 

 and Calvin's (1939) to the same species from Newport Bay, may very 

 possibly be based on P. manimaculis; although P. eriomerus occurs 

 as far south as La Jolla, it appears to be confined to fairly deep water 

 in the southern part of its range. 



Range: Bodega Bay, California, south to Punta Eugenia, Baja Cali- 

 fornia. 



Petrolisthes gracilis Stimpson 

 Plate 27, fig. 2 



Petrolisthes gracilis Stimpson, 1858, p. 227 (listed only; type locality. 

 Gulf of California) ; 1859, p. 74 (description; type locality re- 

 stricted to Guaymas). Lockington, 1878, pp. 395, 396. Rathbun, 

 1910, p. 599. Schmitt, 1921, p. 181 (part; not pi. 32, fig. 4); 

 1924b, p. 383. Glassell, 1938a, p. 443. Steinbeck and Ricketts, 1941, 

 p. 456, pi. 29, fig. 4. Not Nobili, 1901b, p. 13. 



Petrolisics gracilis, Sivertsen, 1933, pi. 3, fig. 31 (not p. 8, pi. 3, fig. 

 30). 



Previous records: Gulf of California. Bahia de Tepoca, Sonora: 

 F. Baker (Schmitt 1924b). Bahia de los Angeles: J. Steinbeck and 



E. F. Ricketts (Steinbeck and Ricketts). Bahia de San Carlos: 



F. Baker (Schmitt 1924b) ; J. Steinbeck and E. F. Ricketts (Steinbeck 

 and Ricketts). Puerto San Carlos, Sonora: J. Steinbeck and E. F. 

 Ricketts (Steinbeck and Ricketts). Guaymas, Sonora: C. \l. P. Stone 

 (Stimpson 1859). Bahia San Gabriel, Isla Espiritu Santo: J. Stein- 

 beck and E. F. Ricketts (Steinbeck and Ricketts). 



Diagnosis: Carapace nearly smooth; no epibranchial spine; front 

 sinuously triangular to trilobate; carpus two and a half to three times 

 as long as wide, anterior margin unarmed, margins subparallel ; outer 

 margin of manus with a thin edge ; merus of walking legs unarmed, 

 naked or nearly so. 



Description: Carapace smooth, punctate, or very finely and evenly 

 granulate. Front sinuously triangular, median groove not distinct; no 



