306 BURTOA. 



mainly covered; ventricose, oblong-ovoid, solid, opaque, 

 strongly grooved except on the embryonic whorls, decussate 

 on the upper part of the later whorls by spiral striae, and 

 covered with a very fugacious cuticle, ornamented with long, 

 pale yellow flames alternating with chestnut-black ones, the 

 color being darker and more uniform on the upper whorls. 

 Spire relatively not long, regularly tapering, the apex mod- 

 erately obtuse. The 7 or 8 whorls are but little convex, and 

 increase regularly to the last one, separated by a decided but 

 not deep suture. Last whorl enormous, swollen, somewhat 

 oblong, less than two-thirds the total length. Aperture slightly 

 oblique, excised, oblong, strongly angular above, the outer 

 side not dilated below, but retracted, with a regularly oblong 

 contour. Interior pearly white, passing into rose-purplish 

 towards the margins. Peristome simple, unexpanded, acute; 

 columellar margin robust, strongly dilated, the dilation with 

 several facets, and below a somewhat Achatina-like eminence 

 gives the base of the axis an appearance of being channelled, 

 but without any trace of truncation. Length 118, diam. 73, 

 aperture 70 by 48 mm. 



German East Africa: Valley of Malagarazi, between Tab- 

 ora and Ujiji. 



Burtoa sebasmia BGT., Moll. Afric. Equat., p. 94, pi. 3, f. 

 1 (1889). 



It is a little less swollen than typical nilotica, more regu- 

 larly acuminate, with less convex whorls, the last less swollen, 

 and especially differs by the form of the columella, which is 

 flattened into facets and has a basal prominence. 



4. B. DUPUISI (Putzeys). PL 23, fig. 47. 



Shell imperforate, ovate, ventricose, rather solid, covered 

 with a brown cuticle, streaked with dark chestnut. Spire 

 short, the apex mamillate. Whorls 6, a little convex, the 

 first nearly smooth, the last three rather regularly plicate- 

 striate, decussated with fine spiral impressed lines ; last whorl 

 large, elongate. Aperture lengthened oblong, the lip acute, 

 pearly or roseate within. Columella roseate, straight, narrow, 

 the margin reflexed, continuous with the basal lip in front, 



