180 BULIMULUS-BOSTRYX-LISSOACME. 



B. PIURANUS Albers. PL 50, figs. 56, 57, 58. 



Shell perforate, acuminate-ovate, rather thin, closely costulate-p lie- 

 ate; dull fulvous, with two encircling brown bands, frequently inter- 

 rupted, and irregularly scattered spots. Spire conic, the apex 

 corneous, acute, smooth. Whorls 7, suture distinct, the earlier con- 

 vex, the last a little shorter than the spire, subangulated around the 

 perforation. Columella straight, slightly receding. Aperture ob- 

 long-ovate, the peristome simple, acute ; right margin arcuate, col- 

 umellar margin reflexed and free. Alt. 20, diam. 9 mill. ; aperture 

 7 mill, long, 4 wide. (Albers). 



Piura, northivestern Peru. 



Bulimus piuranus ALB., Malak. BL, i, 1854, p. 31. PFB., Mon- 

 ogr., iv, p. 491. MOUSSON, Malak. BL, xvi, p. 177. Orthalicus per- 

 icanus H. <fe A. AD., Gen. Rec. Moll., ii, p. 159. 



The specimens before me, two of which are figured, while doubt- 

 less belonging to this species, differ in coloration from Alber's de- 

 scription. One is opaque white, with numerous small corneous- 

 brown maculse and unequally spaced oblique chestnut streaks and 

 an ill-defined peripheral light girdle with traces of several others. 

 Another shell has numerous (6 or 7) girdles formed of more or less 

 coalescent corneous-brown flecks, and no oblique streaks. 



The spire is somewhat attenuated above, formed of quite closely 

 coiled whorls, the apex rather small, but obtuse and smooth. The 

 later 2 or 3 whorls have regular, close rib-striae. Specimens meas- 

 ure: Alt. 19i, diam. 9f, alt. of aperture 8|, width (to outer edge 

 of columella) 6 mill. Alt. 20, diam. 10 ; alt. of aperture 8* mill. 



The species is close to B. striatus King in texture and sculpture, 

 but the spire is much stouter, especially below, as well as longer. 



Mousson records it from Bugua and Amazonas, Colombia, col- 

 lected by Wallis. 



B. ALAUSIENSIS Cousin. PL oO, fig. 59. 



Shell perforated, oval oblong, with slender, conic spire; thin, 

 fragile and subtransparent ; surface grooved with quite strong, irre- 

 gular and noticeably oblique growth-stride ; color dull yellowish- 

 white or clear ashy-gray, visibly marbled, the earlier whorls of a 

 darker shade, which on yellowish individuals is reddish-brown, and 

 on ashy-gray shells is blackish. Whorls 8, moderately convex, 

 slowly and regularly increasing ; suture linear, well-defined. Ear- 

 lier two whorls very small and smooth, forming an acute apex. 

 Last whorl slightly ventricose, with an obsolete median carina. 



