140 .EAST AFRICAN HOMORUS. 



12. H. MAMBOIENSIS (Smith). PI. 60, fig. 83. 



Shell elongate, subulate, somewhat club-shaped ; white, cov- 

 ered with a yellowish and streaked epidermis. "Whorls 10, 

 a little convex, slowly increasing, striated with oblique, deli- 

 cate growth-lines and under a lens seen to be sculptured with 

 close microscopic spiral lines. Suture oblique, rather deep; 

 apex mamillar. Aperture whitish, subovate, a little acuminate 

 above and below, one-fourth the total length; columella arcu- 

 ate, covered with a thin white callous, abruptly truncate in 

 front ; lip thin, regularly curved. Length 46, diam. 13.5 mm. ; 

 aperture 11.5 long, 6.5 wide (Smith). 



East Africa: on the plains within 50 miles of Mamboya 

 (Last) ; Lukwangule Mt., in central Uluguru (Stuhlmann). 



Stenogyra (Subulina) mamboiensis SM., Ann. and Mag. 

 N. H. (6), vi, 1890, p. 158, pi. 5, f. I6.Homorus m., KOB., 

 C. Cab. p. 104. Subulina (Subulona) m., MARTENS, Beschalte 

 Weichthiere, p. 119, with varieties niiida and circumstriata, 

 pi. 5, f. 10. 



An egg from one of the specimens is elongate-ovate and 

 5 mm. in length (Smith). It differs from S. castanea chiefly 

 by the attenuation of the early whorls, producing a cylindric 

 summit. Two varieties are described by Prof, von Martens, 

 as follows : 



Var. nitidus Martens. 



Cuticle strongly glossy, pale yellow with numerous dark 

 brown streaks; suture from the fifth to seventh whorls on- 

 ward, distinctly accompanied by a furrow, producing a 

 grp.nose sutural border. Only 2 specimens, probably not 

 full grown, agreeing in size, length 29, diam. 9, aperture 

 8 mm. long, -l^wide; whorls 7 to 8; and a larger but badly 

 preserved shell. Migere in Butumbi, in old forest (Dr. 

 Stuhlmann). 



Var. circwmstriatus Martens. PL 60, fig. 82. 



Cuticle dark brown, with lighter, yellowish streaks, not 

 glossy; very distinctly and sharply striate spirally. Length 

 32, diam. 11 mm. ; aperture 10 mm. long, 5 wide ; whorls 10. 



