MOLLUSCA FROM EQUATORIAL AFRICA, 211 



Ennea naivashaensis Preston *, vai-. elgonensis, var. n. 



Shell even more cylindrical than the typical form, with more 

 closely set and more pronounced transverse riblets, the aperture 

 also, through not being contracted at the base, has a less triangular 

 appearance. 



Alt. 1"75, diam. maj. 1 mm. 



Eah. Mt. Elgon, Uganda ((7. W. Wooclhouse). 



Ennea mutandaensis, sp. n. (PI. XXXIV. figs. 13, 13 «.) 



Shell differing from E. naivashaensis Preston, from Naivasha, 

 British East Africa, in its darker colour, more cylindrical form, 

 less convex and rather longer whorls, and in the broader and 

 more basally rounded aperture. 



Alt. 2, diam. maj. 1 mm. 



Hab. Between Lake Mutanda and Lake Kivu (Rohin Kemp). 



Ennea nyiroensis, sp. n. (PI. XXXY. figs. 1, 1 a.) 



Shell small, moderately solid, ovately cylindrical, yellowish ; 

 whorls 6, the first four convex, regularly increasing, the fifth less 

 convex and only slightly increasing in breadth, the sixth some- 

 what decreasing in breadth, sculptured with fine, very closely-set, 

 rather oblique, transverse riblets ; suture impressed ; umbilical 

 area presenting the appearance of an elongate, strangulate 

 depression ; columella white, very obliquely descending, out- 

 wardly expanded, extending above into a well-defined, parietal 

 callus which reaches the upper margin of the labrum ; labrum 

 white, narrowly expanded and narrowlj^ reflexed, except above, 

 where it is somewhat contracted ; aperture very obliquely sub- 

 quadrate, armed with a strong, curved, parietal lamella, a broad, 

 bifid, tooth-like projection rather interiorly situate on the inner 

 margin of the outer lip, and a very interiorly situated, lamella- 

 like, basal denticle. 



Alt. 4, diam. maj. 2 mm. 



Aperture : alt. 1, diam. "5 mm. 



Hab. Mt. Kyiro, to the south of Lake Rudolph, at an altitude 

 of 8300 feet {A. Blayney Percival). 



Ennea optata Preston, var. obesa, var. n. (PI. XXXV. 

 figs. 3, 3 a.) 



Shell much broader and more ovate than the typical form t 

 and with half a whorl less ; moreover, the lower denticle below 

 the lamella on the inner margin of the labrum is almost obsolete. 



Alt. 12, diam. maj. 6*5 mm. 



Aperture : alt. 3*5, diam. 2-25 mm. 



Hab. Mt. Kenangop, Aberdare Range, British East Africa 

 (Robin Kern.})). 



* Rev. Zool. Africaine, Brussels, 1911, vol. i. p. 219, pi. xi. iig. 3. 

 t Ann. Mag. Nat. Hist. 1911, vii. pp. 464-465, pi. xi. fig. 4. 



