76 ODONTOSTOMUS. 



Doering's original description is as follows: Shell fusiform-cylin- 

 drical, slender, rather solid, opaque, ashen-buff, closely whitish- 

 costulate; spire long-turreted, rather obtuse. Whorls 10^, slightly 

 convex, the last scarcely one-fourth the total length, pale in front. 

 Peristome white, thickened, the margins joined by a compressed 

 callus. Length 17-19, diam. 3f-4, aperture with peristome 4 mill, 

 long, 3^ wide (Doer.}. 



O. ACONJIGASTANUS Doering. 



Shell rimate, fusiform-turreted, pellucid, very closely striate ; 

 brown, variegated with close opaque-white striae, frequently with 

 longitudinal, brown-reddish spots, sometimes interrupted. Spire 

 turreted, the apex attenuated, rather obtuse. Whorls 12, a little 

 convex, the first uniform corneous-brown, nearly smooth, the rest 

 variegated, closely striate with white ; last whorl nearly one-fourth 

 the length, impressed at the side, two-crested at the base. Aperture 

 oval quadrangular, contracted by 5 teeth ; peristome white, expanded, 

 rather acute, the margins joined by a depressed, sublamelliform pari- 

 etal callus; columellar margin reflexed. Length 18-21, width 5 

 mill.; aperture witli peristome 4 to 5 mill, long, 3^ wide (Doer.}. 



Argentina : Sierra de Aconjigasta. 



0. aconjigastanus DOER., Periodico Zool. ii, pt. 4, p. 245 (1877). 



Differs from 0. charpentieri Grat. by the more numerous, slightly 

 convex whorls and brown color; from 0. maculosus Doer, by the 

 more swollen, wider form, closer whitish striae, and subsolute peri- 

 stome. 



O. CHARPENTIERI (< Grateloup ' Pfr.). PI. 12, figs. 75, 76, 77. 



Shell rimate-subperforate, fusiform-oblong, very delicately striatu- 

 late, corneous whitish, not pellucid ; spire turreted, the apex some- 

 what obtusely attenuated. Whorls 10, scarcely convex, the last 

 slightly exceeding one-fourth the length, with pits at the base and 

 side behind the aperture. Aperture oblong-oval, 5-toothed : one on 

 the parietal wall, a second horizontal lamella on the columella, the 

 third tooth basal', fourth and fifth small, within the right margin. 

 Peristome simple, the margins joined by a thin callus, right margin 

 narrowly expanded, columellar 'margin widely reflexed. 



Length 20; diam. 5-f, length of aperture 6, width 4 mill. 



Length 21, diam. 6 mill. (Hidalgo). 



