BULIMULUS-BOSTRYX-LISSO ACM E. 171 



or blackish-brown, obtuse. Suture impressed. Whorls 5, moder- 

 ately convex, rapidly increasing, the last not descending in front, 

 more convex, inflated, rotund. Aperture slightly oblique, acumin- 

 ate-oval, brown within; peristome acute, unexpanded, margins 

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

 reflexed, half-covering the perforation. Alt. 15, diam. 6 mill. ; 

 aperture 7 mill, long, 4 wide. (Dohrri). 



Peru. 



Bulimulus dewans DOHRN, Malak. Bl., x, 1863, p. 155. PER., 

 Monogr., vi, p. 118. 



The three examples examined agree in the main, but one has the 

 spire somewhat stouter and the last whorl less conspicuously inflated. 

 It is not closely allied to any species known to me. The aperture hap- 

 pens to be formed as in B. stenacme Pfr., which, however, is similar 

 neither in form nor color. The apex is quite obtuse, earliest whorls 

 blue-black or brown, beyond these the rapidly increasing whorls are 

 gray-blue somewhat streaked, the dark brown underlying layer show- 

 ing through in a few places. The suture is rather deeply impressed, so 

 that the spire seems somewhat convex. As far as the middle of the 

 last whorl the breadth increases regularly ; then the whorl becomes 

 swollen and decidedly more convex, giving the shell the appearance 

 of being obliquely produced to the right. The aperture is simple, 

 with sharp lips, dark brown inside, columellar margin narrowly re- 

 flexed, so that the umbilicus is half covered (Dohni). 



B. EXORNATUS Reeve. PI. 50, fig. 55. 



Shell subperforate, ovate-conic, thin, irregularly striate, painted 

 with narrow, denticulate streaks of rufous-corneous and whitish. 

 Spire long-conic, reddish above, the apex rather acute. Whorls 7, 

 moderately convex, the last about three-sevenths the alt, a little 

 compressed at the base. Columella vertical. Aperture slightly 

 oblique, oblong ; peristome simple, acute, the columellar margin nar- 

 rowly reflexed. Alt. 15, diam. 6J mill. ; aperture 6? mill, long, 3 

 wide. (Pfr.). 



Chilon, Bolivia, under dead trunks of cacti (Bridges). 



BuUmiis exornatug REEVE, Conch. Icon., pi. 77, f. 560 (August, 

 1849). PFR., Monogr., in, p. 410. Otostomus (Mormu^ exornatus 

 H. AD., P. Z. S., 1866, p. 442. 



" Of transparent horny texture, neatly marked with opaque white 

 longitudinal lines." Reported from eastern Peru by H. Adams, 

 Bartlett coll. 



