African Non-marine MvUusra. 509 



Whorls 10, not very convex, very gradually increasing, the 

 first 1^ practically smooth, next 2 showinjif close spiral 

 scratches, the next hearing very faint, close, slightly cnrvcd 

 and ol)li(jue transverse stri;e, which continue, stronger and 

 a little more distant, on the later whorls ; suture moderately 

 ohlicpie, shallow, subcrenulate. Aperture subovate; peri- 

 stome simple ; outer lip only moderately curved outward, 

 descending almost straight and vertically in profile ; colu- 

 mella straijiht, erect, margin almost adnately thickened, 

 forming a minute rima ; callus and dentition none. 



Long, 11-8, hit. 2*7 ; apert., alt. 2"o, lat. 1-7; last whorl 

 4G mm. 



Hub. Kenya, Mt. Nyiro, 8300 feet {Percival). 



A more slender form than -S. elongata and distinct from 

 S. ur(juessensis by the sculj)ture of the early whorls. 



Streptostele osculum, sp. n. (PI. XIV. fig. 24.) 



Shell of moderate size, elongate, rimate, thin, rather glossy, 

 translucent, olivaceous. Spire produced, sides convex at 

 the Gth whorl, apex acute. Whorls 9, not very convex, 

 first regularly and gradually increasing, remainder almost 

 ecjual ; the first 4 faintly microscopically punctate, the 

 2ud, 3rd, and 4th showing decreasingly faint traces of trans- 

 verse striation, especially in the suture; remainder sculptured 

 with fine, faint, close, regular, straight, very slightly oblique, 

 transverse stria3 ; suture nearly horizontal, shallow, with a 

 subcrenulate margin. Aperture snboval ; peristome simple; 

 outer li|) hardly curved outward, almost straight in profile, 

 only receding very slightly near the base; columella strai^-ht, 

 erect, margin narrowly reflexed, forming a small rima ; 

 callus very faint ; dentition none. 



Long. 9-4, lat. 2*4; apert., alt. TS, lat. VI ; last whorl 

 3"3 mm. 



Hah. Kenya, Igcnibi Hills (Percival). 



Tliis species differs from S. inyuessensis, perhaps its 

 nearest ally, in being a more slender form with fainter 

 sculpture. 



Slrrptostele oniinaria, sp. n. (PI. XI \'. fig. 25.) 



Shell of fair size, lanceolate, subrimate, thin, smooth, 

 shining, transparent, pale olivaceous. Spire much produced, 

 sides very slightly convex at the 8th whorl, whence they are 

 jiarallel to the base; apex acute. Whorls 10, moderately 

 convex, extremely gradually increasing, first 3 faintly, some- 

 what sparsely microscopically punctate, remainder sculptured 



