176 BULIMULUS-BOSTRYX-LISSOACME. 



Aperture half the total length (more or less), slightly oblique, 

 ovate, white within ; outer lip unexpanded, arcuate ; columellar lip 

 well dilated above. Alt. 14 , diam. 1\ mill. 



Cobija (Cuming), Chili. 



Bulinus pruinosus SOWB., P. Z. S., 1 833, p. 36. Bulimus pruinosus 

 PFR., Monogr., p. 198. KEEVE, Conch. Icon., pi. 20, f. 120. 



The contour varies considerable, and sometimes opaque white, 

 sometimes corneous is the prevailing color. Part of the specimens 

 before me are marked ' Peru," but it is doubtful whether they are 

 from localities now in that State. Others are from Coquimbo. 



B. ROUAULTI Hupe. PL 48, figs. 6, 7. 



Shell perforate, ovate-conic, rather solid, slightly shining, closely 

 striate, and very obsoletely decussated with some rather remote 

 spiral lines. Dull opaque whitish, more or less irregularly macul- 

 ated with pellucid-corneous, or corneous-pellucid with copiously 

 scattered spots and streaks of opaque whitish. Spire conoid, the apex 

 rather acute, corneous, smooth ; suture simple. Whorls 5 to 6, 

 slightly convex, moderately increasing, the last obliquely descend- 

 ing. 



Aperture oval, colored within like the outside, about one-half the 

 shell's length ; peristome simple, acute, the ends joined by a very 

 thin callus ; right margin regularly arcuate, columellar margin 

 dilated and reflexed above, partly closing the perforation ; columella 

 little oblique, lightly arcuate. Alt. 14, diam. 7 mill. (Hidalgo'). 



Chili, at Copiapo (Gay), and Coquimbo, among plants in sandy 

 places (Paz). 



Bulimus rouaulti HUPE in Gay, Historia de Chile, viii, p. 110, pi. 

 3, f. 8 (1854). PFR., Monogr., iv, 478. HIDALGO, Journ. de Conch. 

 1870, p. 54 ; Viaje al Pacifico, p. 86. 



The more lengthened form and the shape of the aperture distin- 

 guish this from B. albicans, which is closely allied. 



B. SIMPLICULUS Pfeiffer. Unfigured. 



Shell perforate, conic-ovate, solid, rugulose-striate, obsoletely de- 

 cussated with spiral lines, when seen under a lens, somewhat shin- 

 ing ; white, with generally scattered pellucid dots. Spire convex- 

 conic, the apex corneous, rather obtuse ; suture minutely crenulated ; 

 whorls 6, moderately convex, the last a little shorter than spire, 

 somewhat rounded at base. 



