1 52 BULIMULUS-BOSTR YX-PERON^EUS. 



Aperture oblong-oval; peristorne simple, acute, straight; col- 

 umellar margin reflexed, half covering the perforation. Alt. 17-19, 

 diam. 6J-7 mill.; aperture, length 6, width 3J mill. (Doer.}. 

 Sierra de Belen, prov. Catamarca, Argentina (Dr. Hieronymus). 



PeroncBus calchaquinns DOER., Bol. Acad. Nac. Cien. Rep. Ar- 

 gent., iii, p. 64 (1879). 



Readily distinguished from famatinus by the color and size ; the 

 aperture is relatively smaller, columellar margin a little more nar- 

 rowly reflexed, whorls more convex, etc. 



B. FAMATINUS Doering. 



Shell rimate, thin, fusiform-turrited, longitudinally rather closely 

 postulate, opaque whitish (or rarely with a few corneous streaks) ; 

 spire long, the apex a little attenuated, slightly obtuse. Whorls 7, 

 the earlier yellowish, smooth ; last whorl slightly exceeding one- 

 third the length. Columella simple ; aperture oblong, oval ; per- 

 istome simple, straight ; columellar margin narrowly reflexed, partly 

 closing the perforation. Length 19, diam. 6 mill. ; length of apert- 

 ture 6-62, width 4 mill. (Doering). 



Sierra de la Rioja, at about 2000 meters alt., between Rioja and 

 Chilecito, Prov. Rioja, Argentina (Stelzner). 



PeronoKUs famatinus DOER., Bol. Acad. Nac. Cien. Rep. Argent., 

 iii, p. 63. 



The jaw has 12 narrow plaits. Teeth in straight transverse series. 

 It is thus a true Bulimulus. 



Group of rhodacme. 



B. RHODACME Pfeifler. PI. 46, fig. 54. 



Shell openly rimate, narrowly long-ovate, rather solid. White, 

 with irregular pellucid or pink inoculation, often suffused ivith a rose- 

 ate blush on the spire, sometimes unicolored white. Surface lusterless, 

 with rude, irregular growth-strife, sparsely decussated, or bearing gran- 

 ules in spiral series. Spire conic, with slightly convex outlines, the 

 apex obtuse. Whorls 6, the upper ones very convex with deep sutures, 

 the lower two less convex, suture slightly and irregularly crenulate ; 

 the apical 1J whorls smooth, corneous or roseate. Last whorl not 

 compressed below. 



