54 CURVELLA, EAST AFRICA. 



' 'The 'arcuate, forwardly bowed growth-lines, the reflexed 

 columellar margin, the delicate, transparent structure of the 

 shell, and small number of whorls for a Stenogyra, indicate 

 the natural position of this species in the genus Hapalus, 

 where it belongs next to subviridescens and elongatus. The 

 structure of the radula, especially the small size of the middle 

 tooth, which formerly led me to place the species in Steno- 

 gyra, also agrees with Hapalus according to the latest re- 

 searches. Stenogyra javana Eve., Opeas semperi Hid. and 

 0. ternatana Bttg. are closely related to this species and may 

 well belong also to Hapalus' 9 (Martens). 



13. C. SUTURALIS (Martens). PI. 8, fig. 20. 



Lanceolate, with very narrow but circular umbilicus and 

 moderately strong strise, bent back below the suture ; whitish ; 

 7 whorls, regularly increasing, the suture being bordered be- 

 low by a somewhat raised girdle which is bounded by a 

 groove; the last whorl gradually tapering downwards, ob- 

 liquely descending to the mouth. Aperture scarcely oblique, 

 less than half the length of the shell, acute-angularly ellip- 

 tical with unexpanded, simple margins. Outer lip arcuate 

 above, lower margin narrowly rounded, columellar margin 

 thickened and strongly twisted, reflexed above and appressed, 

 half closing the umbilicus, and continued as a distinct layer 

 upon the parietal wall. Length 14, diam. 5.5, aperture 6.5 

 mm. long, 3 wide (Martens). 



Kitohaui, on the plateau between Ukuledi and Umbekuru, 

 in the district of Mgao, southwestern part of the German 

 Protectorate .(Lieder). 



Hapalus suturalis MARTENS, Beschalte Weichthiere, p. 129, 

 pi. 5, f. 15. 



14. C. DISPARILIS (E. A. Smith). PI. 8, figs. 16, 21. 



Shell perforate, ovate, a little acuminate above, whitish or 

 waxen, glossy. Whorls 6, slightly convex, parted by a light, 

 oblique suture, longitudinally sharply striated, the striae 

 curved, more or less vanishing below ; last whorl large, rather 

 swollen; apex rather obtuse. Aperture long, inversely auri- 



