BULIMULUS-BOSTRYX-LISSOACME. 189 



ing the perforation. Length 16-20, diam. 9-10 mill.; aperture 9- 

 10* mill, long, 5-6 wide. (Doer.'). 



Sierra de Cordoba, Argentina. 



Bulimulus centraiis DOER., Bol. Acad. Nac. Cien. Rep. Argent., 

 iii, p. 69 (1879). 



Has much affinity with B. apodemetes, with which it lives associ- 

 ated, the form being a miniature of that species; but last whorl 

 longer, its surface smooth. Differs from B. albus in the longer con- 

 tour, and from B. rouaulti in not having the last whorl obliquely 

 descending. Jaw with 13-14 slightly curved riblets, those toward 

 the median part much narrower; basal margin serrate. Teeth in 

 nearly straight transverse series. 



B. VENTAXENSIS n. Sp. PI. 1, fig. 8. 



Shell narrowly perforate, ovate-conic, thin ; closely and obliquely 

 streaked with blackish, brown and pale olive-brown, the earlier 

 whorls lighter ; shining. Surface sculptured with rather coarse and 

 unequal growth-wrinkles. Spire short conic, the apex smooth, white, 

 and obtuse at the rather small tip. Whorls 54, slightly convex. 



Aperture oblique, about half the shell's length, whitish and show- 

 ing the streaks within ; peristome thin, unexpanded and acute, the 

 outer lip regularly arcuate ; columella straightened, descending to- 

 ward the left, the columellar margin reflexed and triangularly ex- 

 panded, flattened, and applied closely over the umbilical area, leav- 

 ing a narrow chink open. 



Alt, 21, diam. 104; alt. of aperture 11 mill. 



Alt. 22, diam. 11 ; alt. of aperture 10* mill. 



Alt. 194, diam. 104 ; alt. of aperture 10 mill. 



Sierra de la Ventana, prov. Buenos Ayres, Argentina. 



As thin a shell as the allied B. apodemetes, but very much more 

 slender and with darker coloring. 



B. COXOSPIRUS Doering. Unfigured. 



Shell perforate, ovate-conic, rather solid ; whitish, opaque ; nearly 

 smooth, densely and irregularly striated. Spire perfectly conical, 

 the apex obtuse. Whorls 5, rather flat, the last more convex, a 

 little longer than the spire ; columella obsoletely folded. Aperture 

 subvertical, oval, pale brown within, shining; peristome simple, 

 obtuse, very narrowly subexpanded, columellar lip somewhat dilated, 



