RIEBECKIA. 207 



f. 1. 8. (R.) gallon sir ensis SMITH, Nat. Hist. Sokotra, etc., 

 p. 132, pi. 13, f. 12. 



"In the form of its aperture this shell approaches the sub- 

 genus Bacillum of Theobald, from Eastern India." (G.-A.). 



"This species is about the same size as S. sokotorana, but 

 differs in form and sculpture. The body-whorl is very much 

 shorter and the other whorls higher than in that species. In 

 fresh specimens the sculpture consists of fine lines of growth, 

 crossed by excessively fine crowded spiral striaB, giving the 

 surface a subangular textured appearance. The epidermis is 

 yellowish olive, interrupted at the middle of the body-whorl, 

 so that the lower is whitish. Here and there occur a few 

 brown streaks in the direction of the lines of growth. The 

 type of the species is a dead bleached shell which has lost 

 most of the surface sculpture through exposure to the 

 weather ' ' (Smith) . 



4. R. ADONENSIS (Godwin- Austen). PL 55, figs. 85, 86, 87, 88. 



"Shell not rimate, dextral, elongately turreted, glassy, pol- 

 ished ; a few faint longitudinal shallow lines of growth ; colour 

 very pale ochraceous; spire high, sides slightly convex; apex 

 blunt, rounded, and rather rapidly tapering at the fifth whorl ; 

 suture shallow, adpressed ; whorls 10, somewhat convex ; aper- 

 ture elongately oval, subvertical; peristome thin; columellar 

 margin thin, straight. Length 24.8, diam. 8.5, alt. apert. 7 

 mm. (G.-A.) 



Sokotra: only found in one locality, east of Hadibu, near 

 a place called Adona, altitude over 1500 feet, rock granite 

 (Bent). Adho Dimellus, 3500-4500 ft; Homhil, 1500-2500 

 ft. (Forbes). Above the Wady Kischen, in crevices in the 

 granite, 1000 meters elev. (Riebeck and Schweinfurth). 



Stenogyra adonensis G.-A., P. Z. S. 1881, p. 810, pi. 69, f. 

 4, 4a. 8. (R.) adonensis SMITH, Nat. Hist. Sokotra, etc., p. 

 134. Stcnogyra socotorana v. MARTS. Nachrbl. D. mal. Ges. 

 1881, p. 137. 8. enodis v. MARTS. Conchol. Mittheil. ii, p. 

 149, pi. 28, f. 14-16 (not of Godwin- Austen). 



"This shell approaches somewhat in its general form to 

 B. mtn/ilfHsis Craven, from Magila, East Africa." (G.-A.). 



