376 MOLLUSCA. 
tuse-angled bird’s beak. ‘The specimen examined had numerous rib- 
like folds on the surface, which were probably caused by its adhesion 
to some ribbed shell. Some specimens since received from Upper 
California confirm this last supposition. 
Figures 482, 482, 482, outside, inside, and lateral views of the 
shell. 
CREPIDULA LINGULATA (Gould). 
Testa parva, depressa, obliqua, rotundata, alba, linets numerosis crebré 
divaricantibus radiata, epidermide pallido induta ; apice acuto, libero, 
prope marginem sito: intus lutescens ; septo linguiformi, excavato, ad 
medium carina diviso et obliquée protruso, ad latus sinistrum profundé 
sinuato. 
Crepidula lingulata, Goutp; Proceed. Boston Soc. Nat. Hist., ii. 
160. August 1846. Expedition Shells, 15. 
SHELL small, depressed, thick at the centre, but flattened and thin- 
ning towards the margin, rounded at base, the apex free, acute, 
shghtly curving to the right, the surface near the margin fur- 
rowed with numerous, delicate, radiating lines, which branch very 
frequently, and covered with a very delicate, pale, fugacious epider- 
mis. Interior pale brownish-yellow, with a broadly expanded flat 
margin. The septum is small, white, excavated ; divided by a deli- 
cate ridge, deeply detached from the left side, and at the middle pro- 
jecting far and obliquely. 
Diameter half an inch; altitude three-eighths of an inch. 
Inhabits Puget Sound, Oregon. 
Like S. capensis, Quoy. 'The only specimen examined seems to 
have been convex and solid in its early growth, afterwards becoming 
flat. Its rounded outline and flat form might lead one to suppose it 
identical with C. nummara, were not the septum so different. 
Figures 481, 481 a, 481 4, exterior, interior, and profile views of the 
shell; 481 ¢, details of sculpture, enlarged. 
