CLASS GASTROPODA 
15 
Purpura nuttallii albescens Dali, 1919 
Proceedings of the United States National Museum, 56:332. 
Completely white or yellowish-white. (Dali.) 
Type in United States National Museum, No. 252894. Type locality, 
San Pedro, California. 
Range. San Pedro, California, to San Quentin Bay, Lower California. 
Purpura nuttallii albofasciata Dali, 1919 
Proceedings of the United States National Museum, 56:332. 
Shell generally preserving the usual brownish color, has a broad white 
band, making it very conspicuous, about the middle of the shell, and one 
on the canal. (Dali.) 
Type in United States National Museum, No. 181827. Type locality, 
San Diego, California. 
Range. San Pedro to San Diego, California. 
Purpura nuttallii aciculiger Valenciennes, 1846 
Plate 30, figs. 12, 12 a, 12 b 
Voyage de la Fregate Venus, Atlas; PI. 10, fig. 1. 
Shell differs in that the shell is smaller, varices are thick and rounded, 
while in the typical form the varices are thin and erectly foliated. Both 
have the same color forms. (Oldroyd.) 
Measurements of P. nuttallii are length, 64; width, 35 mm. Of 
P. aciculger, length, 45; width, 24 mm. (Oldroyd.) 
Range. San Pedro, California, to Scammons Lagoon, Lower Cali¬ 
fornia. 
Genus TRITONALIA Fleming, 1828 
Spire elevated; varices numerous, rounded, sometimes raised; canal 
generally closed. (H. and A. Adams.) (Ocinebra Leach, 1847.) 
Type. Mur ex erinaceus Linnaeus. 
Distribution. West coast of America, Alaska, to Gulf of California. 
Tritonalia gracillima Stearns, 1871 
Conchological Memoranda, Part VI :1. American Journal of Conchology, 7:172* PI 
14, fig. 15. 
Shell small, solid, ovately fusiform, rather slender; spire elevated, 
subacute; whorl six-seven; body whorl about two-thirds of the length 
[313] 
