144 BULIMULUS-ORTHOTOMIUM. 



Bulimulus (Scutalus) acholus MAB., Bull. Soc. Philomath, de 

 Paris, (8), viii, p. 68 (1895). 



Compare B. montezuma, from which this seems to differ in having 

 fewer whorls and narrower form ; if, indeed the diameter assigned 

 be correct. 



B. COSMICUS J. Mabille. 



Shell covered rimate, ovate, apex attenuated; rather thick, a 

 little opaque, white under a thin deciduous epidermis; rudely, irreg- 

 ularly striate, under the lens seen to be quite conspicuously orna- 

 mented with decurrent impressed lines and compressed granules; 

 spire conoidal, little lengthened, apex minute, obtuse, closely costu- 

 late. Whorls 5, irregularly increasing, (the first moderately, the 

 rest very rapidly) ; suture impressed, deeply separating the embry- 

 onic whorls and obscurely denticulated ; the last whorl large, oblong- 

 ovate, inflated, slightly attenuated at the base, obscurely descend- 

 ing in front. 



Aperture vertical, long ovate, acute above ; peristome patulously 

 reflexed, thickened, the terminations joined by quite a distinct callus ; 

 columellar margin widely expanded, closing the rimation, joining 

 the long arc of the outer lip in an obtuse, wide angle. Columella' 

 twisted, impressed in the middle, then arcuate. Alt. 48, greatest 

 diam. 25 mill. ; aperture with peristome 34 mill, long, 20 wide. 

 (Mabille}. 



Sierras of the south of the Peninsula of Lower California (Diguet). 



Buhnulus (Scutalus} cosmieus MAB., 1. c., p. 68. 



Certainly distinct from anything known in America, if Mabille's 

 measurements are to be trusted. 



B. MONTEZUMA Dall. PI. 19, figs. 56, 57. 



Shell large, ovate-conic, deeply rimate, moderately solid ; whitish 

 with rare livid streaks, or dull brown with occasional darker oblique 

 streaks (no spiral color bands). Lusterless, densely and coarsely 

 granose in spiral series. Whorls 6, the earlier If vertically costu- 

 late ; moderately convex. 



Aperture ovate ; peristome broadly expanded outwardly and be- 

 low ; ends converging; columellar margin very broadly dilated 

 above; columella with a convex fold above. 



Alt. 46, diam. 24 ; alt. of aperture 26? mill. 



Alt. 48, diam. 26 ; alt. of aperture 28 mill. 



Alt. 521, diam. 28 mill. 



Alt. 63, diam. 30 mill. 



