116 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
gato-striata, tubulo-spinosa, interdum autem raro inermi, vertice subcen- 
trali, oblique contorto; livida aut lutescente-alba, purpureo contorto-radiata, 
intus intense cinerea vel alba; appendice interna cyathiformi, ampla, late- 
raliter compressa, crystallino-alba, medio interdum cinerea. 
Shell orbicular, sometimes squarely ovate, rather solid and convex, or 
depressed and rather thin, radiately ridged and irregularly wrinkle-striated ; 
generally tube-spined, sometimes, but rarely, without spines, vertex nearly 
central, obliquely twisted; livid or yellowish-white, twistedly rayed with 
purple, interior dark-ash or white; internal appendage cup-shaped, large, 
laterally compressed, crystalline-white, sometimes ash-stained in the middle. 
(Reeve.) 
Type in British Museum. Type locality, not known to writer. 
Range. Trinidad, California, to Tome, Chile, and the Galapagos 
Islands. 
Family CREPIDULIDAE 
Genus CREPIDULA Lamarck, 1801 
Shell oval, limpet-like; with a posterior, oblique, marginal apex; 
interior polished, with shelly partition covering its posterior half. (Wood¬ 
ward, Manual of the Mollusca .) 
Type. Crepidula fornicata Linnaeus. 
Distribution. West Indies, Honduras, Mediterranean, West Africa, 
Cape, India, Australia, West America. Fossil, Eocene .... France, North 
America, and Patagonia. 
Subgenus Crepidula s.s. 
Crepidula grandis Middendorff, 1849 
Beitrage zu cincr Malacologia Rossicct, 101. Tryon, Manual of Conchology , 8:128; 
PL 37, fig. 33. 
Testa ovali, magna, crassa; extus; flavascente aut rufescente, epider- 
mide solida decidua fuscescente obtecta; intus lactaea; apice postico, sub- 
marginali, soluto, uncinato, dextrorsum recurvo; septo solido, ceasso, ad 
dextrum latus impresso; impressione musculari magna, maxime conspicua; 
aperturae margine postico prominente, sub fornicate. (Middendorff.) 
Shell oval, large, thick, externally yellowish or reddish, covered with a 
thick deciduous swarthy epidermis; inside milky; with posterior apex, 
submarginal, corroded, hooked, curved to the right; with solid septum, 
thick, impressed broadly to the right; with large muscular impressions, 
very conspicuous, with posterior margin of aperture prominent, subforni- 
17181 
