014- 



6. Cyther.ea tripla (pi. cxxviii. f. 18, 19, 20, 21, 22), 

 Linn., Mantis, p. 545; Lamarck, no. 12; Chemn. f. 330, 331. 



Cyth. testa trigona, crassa, alta, pallide fulva vel aurantiaca, 

 nonnunquarn fasciis violaceis radiata, intus plerurnque purpurea ; 

 margine ventrali subrccta, lateribus excavatis ; area, postica angu- 

 lata, magna, cordiforrni ; area antica magna, subangulata ; lunula 

 distincta. 



Shell trigonal, thick, deeper than long, of a pale buff or orange- 

 colour, sometimes rayed with purple bauds, sometimes deep purple 

 within. There is a peculiar swell in the disc of the shell near the 

 umbones, then the angle is contracted, and again spreads broadly 

 at the ventral margin. Both sides present large cordiform areas, 

 and the luuule is defined by an impressed line. The spreading of 

 the ventral margin does not take place till the shell is full grown. 



Senegal. 



7. Cythertea corbicula (pi. cxxviii. f. 37, 38, 39), La- 

 marck, Anim. s. vert., sp. 11. 



Cyth. testa ventricosa, alta, subtrigona; latere antico subro- 

 tundato, latere postico subcoarctato ; umbonibus magnis, sub- 

 centralibus ; colore pallide luteo, fasciis castaneis radiato, vel 

 omnino castaneo, intus albo. 



Shell very ventricose, trigonal, with large umbones, and nearly 

 as high as broad ; the hinder side almost narrowed to a point, the 

 front side round. The specimens (f. 39) from California, in 

 Mr. Sowerby's collection, are pale, with dull-brown rays and dull- 

 brown epidermis. The specimen (f. 38) in Mr. Gubba's collec- 

 tion has the rays much brighter. Mr. Cuming has one of a 

 chestnut-colour all over. 



Island of Margarita, West Indies. 



8. CytheRjEa Hindsii (pi. cxxviii. f. 27), Hanley, Sp. of 

 Shells. Wood, Supph pi. 15. f. 35. 



Cyth. testa C. radiates simili, sed altiore ; latere postico brevi- 

 usculo; umbonibus inflatis; lunula et area postica, latis, indis- 

 tinctis, fascia castanea circumscriptis ; colore pallide fulvo, fusco 

 fasciato et angulatim lineato ; epidermide velutina. 



Shell shorter and more inflated than either C. corbicula or 

 C. radiata, the hinder side much shorter than in the former. 

 Instead of a smooth greenish-brown epidermis, it has a velvety 

 coating, as in C. argentina. 



The specimen figured is from Guayaquil Bay. Mm. Cuming. 



