118 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
in his note on the adunca form.For the Norrisia form I would 
suggest Crepidula rugosa Nutt., variety norrisiarum. (Williamson.) 
Type in Williamson Collection in Los Angeles County Museum. Type 
locality, San Pedro, California. 
Range. San Pedro, on Norrisia. 
Described as C. rugosa var. norrisiarum Williamson. 
Crepidula excavata Broderip, 1834 
Proceedings , Zoological Society of London, 40. Conchologia Iconica, 11. Crepidula , 
fig. 4. 
Cal. test, crassiuscula, subtortuosa, laevi, albida vel subflava fusco 
punctata et strigata; intus alba vel alba fusco fuscata, limbo interdum 
fusco cilliato-strigato; long., lat., ly& ; alt., $/% poll. (Broderip.) 
Shell oblong-ovate, rather thick, somewhat twisted, compressed at the 
side, obliquely incurved and beaked at the apex, fulvous-white within and 
without, stained and lineated with purple and reddish-brown; internal 
appendage deep, flat. (Reeve.) 
Type in Museum Cuming. Type locality, not known to writer. 
Range. Monterey, California, to Payta, Peru. 
Crepidula excavata naticarum Williamson, 1905 
Nautilus, 19:50. 
.... this white porcellanous shell with its brown spots might be 
labelled Crepidula rugosa Nutt. var. naticarum . (Williamson.) 
Type in Williamson Collection in Los Angeles County Museum. Type 
locality, San Pedro, on Natica. 
Range. Known only from the type locality. 
Described as C. rugosa var. naticarum. 
Crepidula exuviata Nuttall, 1859 
Plate 85, figs. 7, 8 
Conchologia Iconica , 11. Crepidula , fig. 28. 
Crep. testa elongato-producta, angusta, curvata, sordide alba; appendice 
interna convexa, diaphano-alba. 
Shell elongately produced, narrow, curved, dead-white; internal ap¬ 
pendage convex, diaphanous-white. (Reeve.) 
Type in Museum Cuming. Type locality, Monterey, California. 
Range. California—south. 
1 720 ] 
