i8g7.] dh. j. k. (ihay on thk calyptr.ei d^. 739 



5. Crypta lkssoni. 



Shell whitish, varied with brown or white ; outer surface with 

 concentric ex])anclecl lamina. 

 Crepidula Jimbriata, Reeve. 

 C lessonii, Brod. 

 Ilab. Monterey ; Upper California ; Vancouver Straits. 



** Apex of shell suh central ; portions rather produced, acute. 

 G. Crypta incurva. 



Shell dark brown (rarely white) ; apex acute, rather produced, 

 subcentral ; the outer surface with close, regular, small, spiral or 

 longitudinal ribs. 



Crepidula incurvata, Brod. 

 Ilab. Honduras. Var. 2. ? 



7. Crypta hepatica, Deshayes. 



Shell dark brown, smooth, with a white ray on each side of the 

 a])(X ; apex acute, subcentral, produced. 



Crepidula hepatica, Desh. 



Hub. -? 



Messrs. Adams refer the first of these species to the subgenus 

 Crypta, and the second to Crepipatella. 



3. Garnotia, Gray. 



Shell conical, cup-shaped ; apex acute, posterior, above the margin ; 

 the internal lamina flat, shelving to the level of the apex, leaving a 

 conical cavity beneath the lip, arched inwards or subtransverse. 



Garnotia adunca. Sow. 



Shell smooth or subcostate, dark brown, with a small white spot 

 on each side of the lip ; inner lip pale. 



Crepidida rostrata, C. B. Adams : junior? 

 Hab. Vancouver's Island. 



Tribe III. Shell oblong, transverse, depressed ; apex scarcely raised, 

 posterior, siibtaarginal ; nucleus distinct; spiral cavity ex- 

 panded, shallow, with a transverse plate occupying about two- 

 thirds the width on the left or pillar side of the hinder half of 

 the cavity, and attached by each of the sides to the inside of 

 the shell, and with a radiating fold on the lower surface, form- 

 ing a radiating thickened rib, ending in a concavity like a 

 muscular scar near the edge ; the front edge on the right side 

 of the fold short, forming a deep notch; on the left side ex- 

 panded and rounded, with a notch near the pillar or right 

 edge if the shell. Ergaeina. 



The fold in the j)latc is evidently analogous to the fold and 



