OBELISCELLA. 103 



O. SUBVABICOSA (v. Martens). PI. 26, figs. 38, 39. 



Imperforate, turrite-lanceolate, with sharp, narrow, verti- 

 cal striae, very glossy, yellowish-white with a few pale green- 

 yellowish growth-arrest streaks on all the Whorls; rather 

 acute above. 10 whorls, the first small, approaching globular, 

 the second and third swollen, of subequal size, without striae; 

 the following whorls regularly increasing, somewhat convex, 

 the last but little tapering below. Aperture but slightly 

 oblique, one-third to two-fifths the shell's length, lanceolate; 

 outer margin thin, slightly curved, basal margin narrowly 

 rounded; columellar margin vertical, thick, white, continued 

 on the parietal wall in a very thin deposit. Length 17, diam. 

 5, aperture scarcely 5 mm. long, 2y 2 wide (Martens) . 



German East Africa: Runssoro in bamboo forest, 2600 

 meters elevation; camp no. iii, at 3100 m. elevation (Dr. 

 Stuhlmann) . 



Opeas subvaricosum MARTS., Beschalte Weichthiere 

 Deutsch Ost-Afrikas, p. 126, 296, pi. 5, f. 29 and 21. 



A shorter, somewhat more ventricose form, length 14, diam. 

 5 mm. (fig. 39), but perhaps not full grown, was taken also 

 at Stuhlmann 's Camp III on Runssoro. 



The investigation of the radula of a spirit example by Dr. 

 Meissner has shown that this snail belongs to the Agnatha 

 near Ennea. It may be referable to the genus Obeliscella 

 Jouss., up to this time known only from southern Arabia. 

 (Marts.) 



0. RETTERI (' Rosen ' Kobelt). PL 26, figs. 40, 41. 



Shell imperforate, long-subcylindric, slowly tapering to- 

 wards the apex, thin, translucent, very smooth, but seen to 

 be very delicately striate under a strong lens; deep amber- 

 brown. Spire turrite, gradually tapering-conic towards the 

 summit, the sides slightly convex, apex acute, minute, paler. 

 Suture linear, distinct, appressed-marginate below. Whorls 

 9, a little convex, gradually and regularly increasing, the last 

 slightly larger than the preceding, subcompressed at base, 

 scarcely ascending in front. Aperture small, ovate, com- 

 pressed above and below, colored within like the outside; 



