78 ODONTOSTOMUS. 



0. pop anus DOER., Perioclico Zool. ii, pt. 4, p. 244 (1877). 



This species has the coloration of 0. charpentieri, but differs 

 sufficiently by its larger size, less convex whorls, etc. The differ- 

 ences from the following species have been indicated below. It was 

 found on the trachytic hill of Yerba Buena. 



O. ACHALANUS Doering. 



Shell rimate, fusiform or fusiforrn-turreted, the apex somewhat 

 obtuse ; subpellucid, brownish-ashen, closely wrinkle-striate ; orna- 

 mented with whitish, opaque, irregular striae and some irregular, 

 longitudinal, corneous-brown spots. Spire fusiform-turreted, the 

 apex a little attenuated, somewhat obtuse. Whorls 9 to 10, a trifle 

 convex, the first whorl a little convex, uniform buff-brown, delicately 

 striate, the rest sculptured with irregular, rugulose, opaque, close 

 strias, usually rugulose-sculptured with obsolete, slightly impressed, 

 spiral lines ; last whorl from one-fourth to one-third the shell's 

 length, a trifle convex, more or less calcareous around the aperture, 

 scrobiculate-compressed at the side, two-crested at the base. Aperture 

 subangulate, quadrangular-ovate, contracted by 5 teeth ; two lamelli- 

 form teeth within the left margin, a third at the base, fourth and 

 fifth smaller, within the right margin ; peristome white, expanded, 

 somewhat acute, thickened within, the right margin subangular 

 above, columellar margin a little reflexed ; margins joined by a 

 parietal callus. Length 21-27, width 6-7 mill.; aperture with peris- 

 tome 6 mill, long, 4^ wide (Doer.}. 



Argentina : Sierra, de Achala (Quebrada de Musi). 



0. achalanus DOER., Periodico Zoologico : Organo de la Sociedad 

 Zoologica Argentina, ii, pt. 4, p. 243 (Cordoba, 1877). 



0. martensi is much more ventricose, with more convex whorls. 

 0. popanus is more nearly related, but the present species is 

 narrower, with less angular aperture, the base less pinched and 

 more oval, etc. 



O. MACULOSUS Doering. 



Shell rimate, cylindric-fusiform, long-turreted, thin, closely 

 wrinkle-striate; corneous brown, streakedly maculate with irregular, 

 obsolete whitish stria?, Spire turreted, a little obtuse. Whorls 10, 

 a little convex, the last one-fourth the total length, slightly im- 

 pressed at the side, the base obsoletely two-crested. Aperture sub- 



