130 OXYSTYLA, MEXICO, ETC. 



ing, white inside; peristome simple, white, the terminations joined 

 by a thin callus of the same color; columellar margin dilated, ap- 

 pressed, basal and outer margins slightly thickened. Alt. 53, diam. 

 30, longest axis of the aperture 28 mill. ( C. fy F.) 



Orizaba, prov. Vera Cruz, Mexico (Berendt). 



Orthalicus leucochilus C. & F., Journ. de Conchyl. xvii, p. 423 

 (1869); Miss. Scient. Mex., Moll. p. 459, pi. 18, f. 7, 7a. 



In the single specimen before me (fig. 38), from the original local- 

 ity and collector, the second whorl is yellowish, and there are some 

 very faint broad yellowish streaks behind the outer lip. It resem- 

 bles 0. longa var. strebeli in the coarse surface folds, but not in the 

 shape of either spire or columella. There is one greenish-gray varix 

 on the back of the last whorl, and another bluish one at the begin- 

 ning of the penultimate whorl. It apparently belongs to the group 

 of 0. longa. 



O. PONDEROSA (Strebel). PI. 19, figs. 14, 15, 16, 17. 



Shell thick, hardly shining, apparently without cuticle, embryonal 

 whorls black shading into dark brown, often with a violaceous tinge. 

 Ground-color dirty whitish, with a yellowish tint above, the last whorl 

 more or less reddish brown. On the third whorl longitudinal brown 

 stripes begin, rapidly becoming broad, angularly broken and forked 

 above, sharply defined against the ground-color, but on the last whorl 

 frequently losing in intensity and becoming of a grayish tint, and 

 giving place to continuous streaks or entirely disappearing, so that 

 only the ground-color and the narrow black-brown or dark brown 

 varix-streaks remain, these being bordered behind by a brownish- 

 gray or greenish-gray streak, and near the aperture often crowded. 

 The earlier whorls usually show traces of one band and the last whorl 

 of three indistinct ones. Peristome broadly bordered inside with 

 black-brown, fading though brownish-purple to the white of the in- 

 terior. Sculpture of more or less coarse flat folds, so that the shell 

 appears irregularly, more or less coarsely striated ; toward the suture, 

 where the color is lighter, the folds are sharply developed. Spiral 

 grooves weak, often mingled with coarser furrows, and weak mallea- 

 tion. Columella very strong, short, white, and vertical. 



Alt. 64, diam. 39.6, aperture 33.6 mill., whorls 7. 



Alt. 50.7, diam. 35.2, aperture 30.8 mill., whorls 6. 

 Western Mexico : San Bias, State of Jalisco (Wessel, in coll. Dun- 



