162 STREPTOSTYLA. 



strong, obtuse plica?, somewhat glossy ; corneous- whitish irreg- 

 ularly painted with chestnut streaks, vanishing in the middle 

 of the last whorl, subvaricose. Spire long, the apex acute; 

 whorls 9, a little convex, the last less than one-third the total 

 length. Columellar lamina thin, twisted, subvertical at the 

 base of the aperture, forming a squarish channel. Peristome 

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

 arching forward slightly, basal margin receding. Length 9.5, 

 diam. nearly 5, aperture 3.5x1.5 mm. (Pfr.). 



Chiapas ( Ghiesbreght, in Cuming coll.). 



Spiraxis duUa PFR., P. Z. S. 1856, p. 378 ; Malak. Bl. 1856, 

 p. 232; Monogr., iv, 580. Streptostyla diibia Pfr., MARTENS, 

 Biologia, p. 90, pi. 5, f. 10. 



Von Martens' figure, copied here, is from the type, the ex- 

 act measurements of which are, length 9.33, diam. 4 mm. 



Subgenus PITTIERIA v. Martens. 



Pittieria v. MARTENS, Biologia Centrali Americana, Moll., 

 p. 617 (January, 1901). 



"In the scheme of coloration and the smooth shining sur- 

 face it agrees with various species of Streptostyla, e. g. S. 

 nigricans and S. mitr&formis ; but the columella is scarcely 

 twisted and at the lower end distinctly truncate. From Glan- 

 dina it differs in the very smooth shell, without granulation, 

 and in the columella not being concavely bent" (Martens). 



51. S. BICOLOR v. Martens. PI. 29, fig. 86. 



Shell turrite, rather solid, very lightly striatulate, glossy; 

 rufous-brown with a wide sulphur-colored subsutural zone. 

 Spire long-conic, the apex rather obtuse. Whorls 7%, the 

 first minute, papilliform, the second globose, both uniform 

 brown, the following whorls regularly increasing, slightly 

 convex, with the suture appressed, margins with a groove; 

 the last whorl slowly tapering at the base, slightly convex, 

 not deflexed in front. Aperture subvertical, elliptical, but 

 angular above and below; peristome simple, obtuse, brown- 

 margined within, the throat gray-bluish ; outer margin slightly 

 arcuate above, more so 'below; basal margin produced in a 



