EAST AFRICAN HOMORUS. 139 



sutures between the embryonic whorls. These pliefe are 

 vestiges of ribs such as those on the embryonic shell of 

 Pseudoglcssula. 



Species of the Lake Region and E. Africa. 

 11. II. CASTANEA (Martens). PI. 60, figs. 85, 86. 



Shell 'turrited club-shaped, with weak vertical striation and 

 chestnut-brown, somewhat streaked glossy cuticle, pale yellow 

 under it. Whorls 8-9, scarcely convex, the first small, rather 

 globular, forming a blunt, wart-like apex, the following whorls 

 regularly increasing, with impressed sutures, the last whorl 

 rounded below. Aperture approaching ovate, only a little 

 oblique, whitish within; outer lip thin, margined with black- 

 ish, scarcely arcuate; basal margin broadly rounded; colu- 

 mellar margin arcuate, distinctly truncate below (Martens'). 



Length 47, diam. 13.5, aperture 12 x 8.5 mm. ; whorls 9. 



Length 54, diam. 15, aperture 14x8. mm. ; whorls 10. 



Length 37, diam. 13, aperture 11.5 x 7 mm. ; whorls 8 

 (davata) . 



East Africa: Runssoro, at about 2500-3800 meters, in moss 

 of an Ericina woods, and in bamboo forest; also Wembere 

 Steppe (Stuhlmann). 



Subulina castanca MARTS., Sitzungsbr. d. Ges. Nat. Freunde, 

 1895, p. 129 ; Beschalte Weichthiere p. 118, pi. 5, f . 7, 8, and 

 var. davata, p. 119, f. 9. 



The shell, according to von Martens, is rather variable in 

 proportion of length to breadth, of a usually brilliantly glossy 

 chestnut-brown color, with more or less dark streaks, some- 

 times lighter yellowish streaks also. Of spiral striae there is 

 only something to be seen on the uppermost whorls. There is 

 a more club-shaped form (var. davata, fig. 86), which in- 

 creases in diameter more rapidly from the beginning, and a 

 more elongated (typical, fig. 85) less rapidly widening. In 

 the more club-shaped shells the height of the last whorl, meas- 

 ured behind, is more than one-third that of the shell; in the 

 elongated shells it is somewhat less than one-third. 



