VITRINA. 153 



Y. ANGOLENSTS, Morelet. PL 33, figs. 31-33. 



Depressed globose, thin, subrugulose, radiately plicatulate at 

 the suture, diaphanous, scarcely shining, brownish yellow ; spire 

 conoidally depressed; suture margined ; whorls scarcely 4, the 

 last depressed rounded, shining below ; aperture oblique, lunately- 

 rounded, the columellar margin very shortly reflected at its 

 insertion, forming a narrow slit. Diam. It, alt. 9 mill. 



Angola. 

 Y. CORNEOLA, Morelet. PL 33, figs. 34-36. 



Depressed globose, thin, inconspicuously striate, not shining, 

 diaphanous, orange-brown ; spire depressed-conoidal, suture very 

 narrowly margined ; whorls 3j, the last lightly compressed at the 

 periphery ; aperture oblique, lunately-rounded, columellar margin 

 very narrowly dilated and reflected at its insertion. 



Diam. 8, alt. 4 mill. 



Angola, W. Africa. 

 Y. DUMETICOLA, Dohrn. PL 33, figs. 37-39. 



Depressed globose, very thin, lightly striate, very shining^ 

 vitreous horn-color ; whorls 3, rapidly enlarging, the last rounded, 

 slightly more convex below ; aperture oblique, lunately rounded, 

 partly showing the whorls. Diam. 9, alt. 5*75 mill. 



Prince's Isl., Gulf of Guinea. 



IY. East and South African Species. 



Y. SENNAARIENSIS, Pfr. PL 33, figs. 40-42. 



Turbinatety depressed, thin, obliquel} 7 rugosely striate, some- 

 what shining, pellucid, corneous-green, usually dark stained; 

 spire subturbinate, mucronate, suture deeply impressed ; whorls 

 3, convex, the last obliquely flattened, and obsoletely angulate 

 on the periphery ; lip thin, subinflected above. 



Diam. 6-6, alt. 3 mill. 



Sennaar, Nubia. 



Y. DARNAUDI, Pfr. PL 33, figs. 43, 44. 



Depressed globose, rather thin, irregularly striulate, somewhat 

 shining, light greenish corneous ; spire convex, obtuse, suture 

 narrowly margined; whorls scarcely 3, convex, rapidly enlarging; 



