166 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.21 



Habitat: Sandy mud. (Bell) On floating weed. (Crane, 1937) On 

 underside of stone at extreme low-tide level. (Crane, 1947) Of the nine 

 stations for which data on bottom type are available, four are sand (one 

 with mud), two coralline, two rock (one with sand), and one mud with 

 sand. Decorated with large grains of sand and bits of weed. (Crane, 

 1937) 



Depth: Shore to 20 fathoms. 



Size and sex: Males in the Hancock series are from 5.6 to 14.3 mm, 

 females from 6.2 to 17.4 mm, the former in each case being young. There 

 are no ovigerous females. The largest male recorded measured 19.0 x 19.5 

 mm, including spines (Sivertsen) ; the largest female was the 19.1 mm 

 type. 



Remarks: This species has been erroneously recorded as the Pacific 

 counterpart of the Atlantic Pitho aculeata by Stimpson and of P. 

 Iherminieri by A. Milne Edwards. 



The Ecuadorean localities of Cape San Francisco and Manta Bay 

 are new for the species, unless Cuming's types were collected in this area 

 instead of the Galapagos Islands, as is believed to be the case with others 

 of Bell's species. 



Pitho sexdentata was taken in the same dredge hauls with P. picteti 

 at Los Frailes and at Maria Magdalena Island, Mexico. Tiburon Island 

 is a range extension north. 



Pitho picteti (Saussure) 

 Plate J, Fig. 1 ; Plate 17, Fig. 1 



Othonia picteti Saussure, 1853, p. 357, pi. 13, fig. 2. Stimpson, 1857b, 



p. 455. A. Milne Edwards, 1875, p. 118. Lockington, 1877c, p. 70. 



Streets and Kingsley, 1877, p. 104. 

 Micippa ovata Lockington, 1877c, p. 68; type localities: Port [Puerto] 



Escondido, Mulege Bay, Los Angeles Bay, San Jose Island, and 



La Paz, Gulf of California ; types not extant. 

 Micippa ovata, var. laevis Lockington, 1877c, p. 69; type locality, Gulf 



of California; types not extant. 

 Othonia nicholsi Rathbun, 1892, p. 257, pi. 35, fig. 3 ; type locality, Gulf 



of California; female holotype U.S.N.M. No. 15822. 

 Pitho quinquedentata, Rathbun, 1898, p. 578; 1910, p. 573 (part: the 



Gulf of California locality). Boone, 1929, p. 563, figs, la-lb. (Not 



P. quinquedentata Bell). 

 Pitho picteti, Rathbun, 1923b, p. 635; 1924c, p. 379; 1925, p. 359, pi. 



130, figs. 2, 3 ; pi. 252, fig. 1. Finnegan, 1931, p. 624. Glassell, 1934, 



P. 454. Crane, 1937, p. 59. Steinbeck and Ricketts, 1941, p. 466. 



