82 ODONTOSTOMUS. 



thickened; peristome thick. Length 12-13, diam. 3-4, aperture 

 with peristome 3^ mill, long, 2 wide (Doer., Boletin). 



Argentina : Sierra de Cordova, on the western slope, on the hills 

 of Calera around the town of Cordova, etc. 



0. tumulorum DOER., Bol. Acad. Cienc. Cord., p. 456 (1875); 

 Periodi<:o Zoologico, i, pt. 3, p. 187 (1875). 13. tumulorum Doer., 

 Ivors., Nachrbl.. 187G, p. 7 PFR., Monogr., viii, p. 611. 



Doering's more extended description follows: 



Shell rimate, cylindric-fusiform, small, the apex attenuated, obtuse, 

 rather solid, closely and very minutely striate, nearly smooth, slightly 

 shining ; corneous-whitish, variegated with pellucid-corneous. Spire 

 fusiform-turreted, a little obtuse. Whorls 9, a trifle convex, the first 

 huff-corneous, nearly smooth, the rest whitish, variegated with pellucid- 

 corneous spots, the last whorl pellucid corneous ornamented with 

 close whitish stria?, one-fourth the total length. Scrobiculate at the 

 side and base, the latter shortly two-crested. Aperture suboval, con- 

 tracted by 5 teeth : a compressed one in the middle of the parietal 

 margin, the second horizontal, twisted, on the columella, a third 

 within the base, the fourth, compressed, and fifth small, close together 

 within the outer lip (Doer., Per. Zool.). 



Length 12, diam. 3^, length of aperture 3^, width 2f mill. 



Length 13^, diam. 4, length of aperture 3|, width 2 mill. 



O. PUCURANUS Doering. 



Shell rimate, cylindric-fusiform, brown-corneous or grayish-brown, 

 slightly shining, closely, minutely striate, usually variegated with 

 whitish, interrupted, irregular stria:-. Spire fusiform-turreted, the 

 apex a little obtuse ; suture deep. AVhorls 9, a trifle convex, the 

 last about one-fourth the total length, shortly two-crested at the base, 

 scrobiculate at the side. Aperture somewhat angularly suboval, 

 contracted by 5 teeth : one in the middle of the parietal wall, a second 

 twisted tongue-shaped one on the colnmella, the third la sal, fourth 

 and fifth small, within the outer lip. Peristome white, thick, the 

 margins joined by a compressed, lamelliform callus ; right margin 

 shortly arcuate above, narrowly expanded below, columellar margin 

 more widely reflexed. (Doer., Per. Zool.) 



Length 12^, diam. 3^, length of aperture 3^, width 2^ mill. 



Length 14, diam. 3^, length of aperture 3^, width 2^ mill. 



Length 14^, diam. 4, length of aperture 3^, width 2| mill. 



