184 Transactions of the Royal Society of South Africa. 



rounded. Whorls 8, rather flat, regularly increasing, the first 2 practically 

 smooth, remainder sculptured with rather faint, close, fairly regular, curved 

 vertical striae ; suture simple, shallow. Aperture subpiriform, peristome 

 simple, acute, outer lip projecting rather sharply forward for about 1| mm., 

 at which point it is slightly sinuate, and then receding more gently to the 

 base ; columella very slightly concave, not truncate, margin very narrowly 

 reflexed, nearly concealing the narrow rima. 





sp V 



C I 



15- 





6^ 9 



C I A- T 



Text-fig. 22. — Oj;eas praecox Connolly, Zangwe Basin, Portuguese E. Africa. 



a, I row of radula of immature but fertile specimen ; x300 (approx.) 



b. Individual teeth enlarged. 



c, \ row of radula of embryo ; X 300 (approx.). 



d. Individual teeth enlarged. 



Long. 11-3, lat. 3-0; apert. alt. 3-0, lat. 1-2 ; last whorl 5-0 mm. 



Hab. L. Marques. Zangwe River Basin (type, Cressy). 



Nyasaland. Port Herald Hills (Harger). 



A puzzling species, varying considerably in contour of spire and slightly 

 in length of whorl between sutures, the type being more slender and slightly 

 shorter-whorled than other individuals, whose greater breadth imparts to 

 them rather a different aspect. However, a considerable series from the 

 type locality exhibits every stage of transition, and some of these exactly 

 match some of those from Port Herald, while others from the latter district 

 show still further slight variation. 



Colonel Peile has kindly furnished drawings of the radula (text-fig. 22). 



