474 ^fr. H. B. Preston on 



peiiostracum : whorls 7, nioderutely flat, maiked only witii 

 lines <if growth ; suture impressed ; cokimella somewhat 

 curved, abruptly truncate; labrum simple, receding below; 

 aperture inversely auriform. 



Alt. 16"75, diam. maj. 4*5 mm. 



Aperture : alt. 4o, diam. 2 mm. 



Bab. Mount Kenia, 6000-8000 feet, British East Africa. 



Opeas orestias, sp. n. (Fig. 30.) 



Shell fusiform, yellowish white, thin, rimate, with obtuse 

 and rather large apex ; whorls 5^, convex, the first one and a 

 half smooth, the remainder sculptured with somewhat coarse 

 transverse riblets; suture deeply impressed; perforation 

 reduced to a mere chink ; columella descending obliquely, 

 reflexed; labrum acute, simple ; aperture elongately ovate. 



Alt. 4 mm., diam. maj. 2 mm. 



Aperture : alt. 1, diam. nearly '5 mm. 



Bab. Mount Kenia, at an altitude of 9000-10,000 feet, 

 British East Africa. 



Opeas terebra, sp. n. (Fig. 31.) 



Shell elongately subulate, shining, yellowish white, thin ; 

 whoils lOi, the apical whorls smooth, submammillary, the 

 remainder flattish, sculptured with fine, transverse, arcuate 

 costula3 ; suture impressed, rather coarsely crenellated by the 

 terminations of the transverse costulse ; columella thickened, 

 descending in a slight curve ; labrum white, slightly reflexed ; 

 aperture inversely auriform. 



Alt. 12'5, diam. maj. 2"75 mm. 



Aperture : alt. 2"25, diam. 1 mm. 



Bab. Between Bumruti and Mount Kenia, British East 

 Africa. 



Opeas rumriitiensis, sp. n. (Fig. 32.) 



Shell rather shortly subulate, thin, semitransparent, wax- 

 coloured, with rather blunt apex ; whorls 6, slightly convex, 

 sculptured with transverse, arcuate, somewhat closely-set 

 costulse ; suture impressed, margined below ; columella 

 verticiilly descending, narrowly reflexed ; labrum simple ; 

 aperture inversely auriform. 



Alt. 6, diam. maj. 2, diam. min. 1-75 mm. 



Aperture: alt. 1-75, diam. '5 mm. 



Bab. Between Rumruti and Mount Kenia, British East 

 Africa. 



