BURTOA. 303 



South of Lake Tanganyika, between lendne and Pambete 

 (Giraud). 



Bulimus giraudi BGT., Notice Prodromique sur les Mol- 

 lusques recueillis par M. Victor Giraud dans la region merid- 

 ionale du lac Tanganyika, p. 12 (1885). Burtopsis giraudi 

 BGT., Moll. Afr. Equat, p. 98, pi. 5, f. 1 (1889). 



Var. OBLIQUA Martens. PI. 30, fig. 18. 



Thick-shelled, the last whorl very ventricose, and strongly, 

 obliquely descending to the aperture, the penultimate whorl 

 therefore conspicuously convex there ; the spire rapidly taper- 

 ing, rather acute at the summit. Aperture about three-fifths 

 the total length. Outer margin pretty thick, very oblique 

 and but slightly arcuate above, the lower part moderately 

 arcuate. Columellar margin oblique. In otherwise similar 

 specimens the umbilical crevice may be either rather open or 

 almost wholly closed. Length 109-114, diam. 72-77, length of 

 aperture 65-69 mm. 



Ussagara, between Kidete brook and Ngombo, on the left 

 side of the Mkondogwa river (G.^Lieder) ; Mpwapwa (Ger- 

 rard) ; east side of Tanganyika, between Karema and Kiandu 

 (Reichard), and at Kala. 



L. n. var. oUiqua MARTS., Nachrbl., 1895, p. 181; Beschalte 

 Weichthiere, pp. 96, 97. 



A form intermediate between obliqua and emini was taken 

 with var. emini in Ugogo by Dr. Stuhlmann. 



Var. GRANDIDIERI n. n. PI. 26, fig. 16. 



Shell narrowly rimate (the chink almost wholly covered), 

 large, oblong-ovoid, swollen, rather thin, slightly subpellucid, 

 glossy, whitish with sparse and irregular subundulating 

 rufous fiammules, well striated, and elegantly decussate with 

 spiral lines, subgranulose-fringed below the suture on the last 

 whorl. Spire shortly oblong-tapering, a little obtuse at the 

 summit. Whorls 7, convex, regularly increasing, separated 

 by an impressed suture, the last whorl large, more than half 

 the alt., oblong-convex, rather swollen, slowly descending to 

 the aperture. Aperture nearly vertical, lunate, oblong, an- 



