MEXICAN OPEAS. 215 



basal and outer margins acute. Length 14.5, diani. 2.5, aper- 

 ture 2 x 1.25 mm. (C. &F.}. 



Guatemala (F. Sarg). 



Opeas gladiolus C. &. F., Journ. de Conchyl. xxv, 1877, p. 

 272 ; Moll. Mex. i, p. 604, pi. 26, f . 10. MARTENS, Biologia, p. 

 293, pi. 17, f. 8 ? (Merida, Yucatan). 



This species, of a veiy elongate shape with many nearly 

 flat whorls, seems very distinct from its 'congeners in Mexico 

 and Guatemala. It is not without similarity to 0. colimense, 

 but it is more slender, more subulate, the whorls are more 

 numerous, proportionately smaller, and the aperture is not so 

 large (C. &. F.). 



22. 0. COLIMENSE (Crosse et Fischer). PI. 29, figs. 92, 94. 



' ' Shell with an almost closed umbilical crevice, long-turrited, 

 thin, translucent, with fine longitudinal stria?, pale corneous- 

 whitish, with inconspicuous transverse whitish lines which 

 sometimes disappear. Spire long, the apex obtuse. Suture 

 much impressed, deep, whitish. Whorls 10, not very convex, 

 the first two smooth, the laist much shorter than the spire. 

 Aperture subvertical, oblong-ovate ; peristome simple, unex- 

 panded, the margins distant, the columellar margin a little 

 dilated, basal and outer margins acute. Length 15.5, diam. 

 3.25, aperture 3x2 mm." (C. & F.). 



State of Colima, S. W. Mexico (Xantus, type loc.) ; Cor- 

 dova, State of Vera Cruz (Hoge). 



Stenogyra colimensis C. & F., Journ. de Conch, xvii, 1869, 

 p. 424. Opcas c., C. & F., Miss. Sci. an Mex., Moll, i, p. 603, 

 pi. 26, f. 9. Martens, Biologia, Moll., p. 293. 



This species is notable for its length, the spire tapering 

 regularly as in 0. gracile, but composed of shorter, more con- 

 vex whorls. The spiral whitish lines mentioned by Crosse and 

 Fischer are probably due to incipient disintegration of the 

 cuticle, letting air into it. They are present to some degree 

 on three of the four specimens I have seen, being most con- 

 spicuous on the last whorl. The largest one before me meas- 

 ures, length 14, diani. 3.2, aperture 3 mm., whorls 9%. 



