270 CALYPTR^ID^. 



Genus L,EPETA, Gray. 1840. 



Shell obovate, depressly conical, surface with radiating strias ; 

 apex eccentric, posterior ; aperture oval, muscular impression liorse- 

 shoe-sliaped, open anteriorly. Animal blind. 



Lepeta caeca. 



Shell small, white, with numerous diverging ribs, checked by revolving lines, 

 apex central. 



Lepeta cceca (Patella), Muller, &c. ; Stimpson, Check Lists, 4. 



Patella Candida, Couthouy, Sillim. Journ. o. s. xxxiv. 217 (1838); Bost. Journ. Nat. 



Hist. ii. 86, pi. 3, fig. 17.— Gould, Inv. 1st ed. 152. — Dk Kav, N. Y. Moll. 61. 

 Pilidhim candidum, Stimpson, Shells of New En<^laiid, 29. 



Shell small, conical, white, oval, having- numerous minute radi- 

 ating ribs, traversed by equally fine concentric lines, which give the 

 surface, when viewed under a magnifier, the appearance of 

 network ; summit nearly central, margin slightly scalloped 

 1)V the termination of the ribs; interior Avhite. Lensth, 

 seven twentieths of an inch ; height, one tenth of an inch ; 

 „ breadtli, one fifth of an inch. 



Only three specimens of this shell are yet known. The 

 first one found was taken by Mr. Couthouy from the stomach of a 

 fish caught off Barnstal)le, and was described by him. A second 

 has since been found by Mi\ W. W. Whieldon, of Charlestown. It 

 is at once distinguished by its checkered or granulated surface, no 

 other species, yet described, having that character. 

 Greenland (^Mailer'). 



Family CALYPTR^ID^, Brod. 



Shell basin-shaped, serving as a cover to the animal ; distin- 

 guished from the preceding family by the branchias being situated 

 in a peculiar cavity upon the back. 



Oeims CREPIDULA, L.\m. 1799. 



Shell oval, arched, somewhat boat-shaped, with an imperfect 

 spire pressed against the margin ; cavity partially divided within by 

 a horizontal partition. 



