622 



but is characterized by waved, deep- cut, conceutric ridges. The 

 hinder side is marked with deep brown. 



Jhngaran, Island of Negroes, Philippines. Cuming. 



34. Cyther^ea Argentina (pi. cxxix. f. 62), Sowerby, sen., 

 Pro. Zool. Soc. 1835. p. 46. 



Cyth. testa subtrigona, alba, subasquilaterali ; latere antico 

 paulo breviore, postico subacurninato ; margine dorsali postico 

 rectiusculo, declivi, ventrali rotundato ; epidermide tenui, cornea, 

 extiis velutina, alba, quasi argentata, induta. 



Shell subtrigonal, white, subequilateral ; the anterior side a 

 little the shorter, the hinder side rather acuminated ; the ventral 

 margin rounded; epidermis thin, pale-green, with a velvety, 

 silver-like coating over it. 



Gulf of Nocoiya, Central America ; sand-banks at low water. 

 Cuming. 



35. CytheRjEA nobilis (pi. cxxx. f. 68), Reeve, Pro. Zool. 

 Soc. 1849. 



Cyth. testa crassa, alba, rotundata, concentrice subundatim 

 costata, ventricosa ; latere antico brevi, rotundato, latere postico 

 uuisulcato; margine postico dorsali et ligamento elongatis; lu- 

 nula distincta, excavata ; umbonibus magnis. 



A fine, large, heavy, ribbed, rounded, white shell, with hinder 

 dorsal margin and ligament high and long ; lunule excavated, and 

 anterior side short ; a depressed ridge at the posterior side. 



36. Cyther.zea purpurata (pi. cxxx. f. 67), Lamarch, Anim. 

 s. vert. Cyth. no. 9. C lubrica, Broderip, Zool. Proc. 1835. 



Cyth. testa nitente, crassa, rotundata, subcompressa, purpurea, 

 intus alba, sulcis insequalibus cincta, postice obscure angulata; 

 margine dorsali subexcavata. ; lunula impressa. 



Shell thick, shining, rounded, purple, white within, rather com- 

 pressed, girt with unequal, distant grooves ; dorsal margin rather 

 hollow ; lunule impressed. 



Puerto Portrero, Central America. Cuming. 



37. CYTHERiEA UMBONELLA (pi. CXXX. f. 63, 64, 65, 66), 



Lamarch, Anim. s. vert. Cyth. no. 55. Var. C. nivea, Hanley, 

 Sp. of Shells, p. 97. 



Cyth. testa, crassa, ventricosa, nitente, ovali, ina;quilatera, pur- 



