Quarterly Journal of Conchology. 253 



Length 0.275, breadth 0.175. 

 Hab. Zanzibar. 



j\Ir. Gibbons found but three specimens of this interesting 

 species, all in one spot amongst dead leaves, of which only one 

 was living. Islx. Sheppard, of H. M. S. London, found specimens 

 of this species at the roots of Banama trees, 



I have very great pleasure in associating with this interesting 

 species the name of its discoverer. 



Its nearest ally is Streptaxis Kirkii, Dohrn, from Lake Nvassa, 

 from which it is, however, quite distinct. 



Zonites (?) ventrosa, Gibbons, MS. (Plate II. fig. 2). 



Shell depressed, rounded, thin and glossy, of a deep rich brown 

 colour, with faint transverse striula;, strongly marked at the 

 suture ; whorls four, slightly convex, inflected above, the last 

 occupying half the shell : periphery rounded : base\&xy convex : 

 spire depressed : apex obtuse, rounded : suture broad and very 

 deep : mouth lunate, nearly as long as broad : the peristome 

 semicircular, thin and direct except near the umbiHcus where it 

 is reflected : umbilicus deep and very broad disclosing the 

 interior of the spire. 



Length 0.175, breadth o. i. 



Hab. Zanzibar. 



Mr. Gibbons found but a single specimen of this Zonites, dead, 



amongst dead leaves. Mr. Sheppard has, however, taken living 



specimens at the roots of banama trees. 



Buliminus olivaceus, Gibbons, MS. (Plate II., fig. 5). 



Animal white, or yellowish white, opaque. 



Shell, oblong-conical, thin, glossy, semitransparent, of a darkish 

 horn colour, distinctly and regularly striate transversely : epider- 

 mis rather thin, distinct : whorls eight, rounded, the last large 



