DRYM^EUS LEIOSTRACUS. 95 



Aperture oblique, small, showing the external pattern within ; 

 peristome thickened, white or tinted, expanded, the columellar mar- 

 gin triangularly dilated above ; columella straight and vertical above. 



Alt. 25, diam. 13, length of aperture 11 mill. 



Alt. 26, diam. 12, length of aperture 10 mill. 



Alt. 20, diam. 10^, length of aperture 9 mill. 



Forests of Prov. Bahia, Brazil (Spix). 



Bulimus zebra SPIX, Testae. Bras. p. 8, pi. 7, f. 5 (not of Brug.). 

 DESH. in Lam., An. s. Vert, viii, p. 242. Helix zebra MORI- 

 CAND, Mem. Geneve, vii, p. 432 Bulimulus onager BECK, Index 

 Moll. p. 64 (1838), based upon Spix's B. zebra. Bulimus onager 

 REEVE, Conch. Icon. pi. 45, f. 284 DESH. in Fer., Hist., p. 73, 

 pi. 145, f. 10, 11. PFR., Conchyl. Cab. p. 167, pi. 50, f. 9, 10; 



Monogr. ii, 107; iii, 342; iv, 403; vi, 50 Bulimus vittattis KCSTER, 



Conch. Cab., pi. 16, f. 16. 



D. onager is allied to D. vimineuf, but the aperture is entire and 

 rounded below, while in the other species it is produced and effuse at 

 the lower outer part. 



The typical form (fig. 16) has longitudinal stripes, usually quite 

 irregular and often bifurcating near the suture, but extending to the 

 base. This varies to forms having a small uniform brown tract 

 around the columella, or enlarged to cover half or even all of the 

 base. 



Color-var. subtuszonata n. v. (fig. 17). Base with a wide white 

 zone, bounded by dark bands above and below. In this form the 

 longitudinal stripes are generally broad and bold, and the shell is 

 frequently larger than the typical form, attaining a length of 28 mill. 



D. VIMINEUS (Moricand). PI. 14, figs. 18, 19, 20. 



Shell perforate, oblong-pyramidal, rather solid ; white or whitish, 

 with longitudinal stripes of purple-brown extending from suture to base, 

 some of them often accompanied by ochre-colored stripes ; with 

 sparsely irregularly scattered dark dots, which are translucent by 

 transmitted light. Surface smooth except for slight growth lines, 

 somewhat shining. Spire high, the apex somewhat obtuse. Whorls 

 7, moderately convex, the last obscurely angular at the periphery, in 

 front. 



Aperture oblique, chestnut-colored and streaked within, more or 

 less produced at the outer basal portion, like a wide, shallow channel 



