CALYPTR^EA. 119 



C. RADIATUM, Brod. PI. 33, figs. 52, 53. 



Comically orbicular, whitish rayed with dark chestnut without 

 and within, radiately striated and very closely finely ridged ; 

 internal appendage cup-shaped, produced, concavely compressed 



on one side. 



Bay of Caraccas. 



Broderip describes the cup as " pressed in on one side, adher- 

 ing to the shell not only by its apex, but also by a lateral seain, 

 which scarcely reaches to the rim of the cup." A doubtful species. 



Section BICATILLUS, Swainson, 1840. 

 C. EXTINCTORIUM, Lam. PL 33, figs 46-51. 



Thin, shining, smoothish, apex elevated and twisted ; brownish 

 white, more or less ra^ed or spotted with chestnut ; interior 

 appendage small, cornucopia-shaped. 



Malacca, Singapore, Mauritius. 



It is C. Isevigatum of Chenu, (7. morbidum, Reeve (figs. 48, 49), 

 and C. lividum, Reeve (figs. 50, 51), a brown variety. 



C. VERRUCOSUM. Reeve. PL 33, figs. 54, 55. 



Shell orbicular, conical in the middle, top central, somewhat 

 mamillary, yellowish cream-color, rather opaque, more or less 

 rayed and spotted with chestnut, surface interruptedly laterally 

 wrinkled ; cup small, cornucopia-shaped. 



Yucatan (Norman). 



Described without locality, which is supplied from specimens 

 in Mus. Philad. Acad. 



C. MAMMULA, Rochebrune. (Unfigured.) Senegambia. 



Genus CALYPTRJ3A, Lamarck, 1799. 

 C. SINENSIS, Linn. PL 34, figs. 56, 57 ; PI. 30, fig. 7. 



Orbicular, thin, smooth or finely scaled, shining within; white 

 or yellowish white. 



Europe. 



Dr. Jeffreys writes : "It would seem that this mollusk seldom, 

 if ever, leaves its place of abode. I found some at Sark, living 

 attached to small pebbles, each pebble having scarcely a broader 

 surface than the circumference of the shell, which closely fitted 

 the sinuosities of the stone. Both shell and pebble were en- 



