BULIMULUS-BOSTRYX-LISSOACME. 159 



margin dilated above, vaultingly reflexed, half-covering the umbil- 

 icus. {Hidalgo}. 



Alt. 29, diam. 14 mill. (Hid.). 



Alt. 26, diam. 12 mill. ; aperture 14 mill, long, 6 wide inside. 



Quito (Delattre) ; Ibarra and Otavalo (Martinez) ; Pasto (Leh- 

 man n), Ecuador. 



Bulimus quitensis PFR., P. Z. S., 1847, p. 230 ; Monogr.,ii, p. 182. 

 REEVE, Conch. Icon., pi. 48, f. 317. HIDALGO, Viaje al Pacifico, 

 p. 130, pi. 7, f. 5-8 ; Journ. de Conchyl., 1870, p. 63. DKR., Jahrb. 

 d. D. M. Ges., ix, 1882, p. 379. 



Hidalgo describes the following varieties of coloring : 



Var. : Shell brown, generally somewhat violaceous on the spire, 

 not streaked or indistinctly so, the aperture entirely blackish-brown 

 within (figs. 18, 19). 



Var. : Shell almost unicolored, whitish. 



The figure given by Reeve is said by Hidalgo to represent a 

 slightly deformed individual, the subangulate character of the basal 

 lip being abnormal. Figures 16, 17 represent the ordinary form. 



The shell resembles B. catlowicePfr., and as the apex is unknown, 

 it may prove to be a Scutalus. I have not seen the species. 



B. CEROPLASTA n. sp. PI. 50, figs. 38, 39. 



Shell perforated, ovate-conic, thin, somewhat translucent, waxen 

 white. Surface shining, with irregular fine wrinkles of growth. 

 Spire stout, conical, the apex obtuse, smooth. Whorls 6, the first 

 obtuse above with comma-shaped apical pit, the next very convex ; 

 following whorls moderately convex. 



Aperture irregularly ovate, narrow above, one-half the length of 

 shell, white within. Outer lip gently and regularly arcuate, thin 

 and acute. Columella straight, vertical, its edge broadly and flatly 

 dilated, appressed above the umbilical perforation. Parietal wall 

 convex, with a very light callus. 



Alt.- 19?, diam. 10, alt. of aperture 9 mill. 



Alt. 20i, diam. 10, alt. of aperture 10 mill. 



Balsas, valley of Maranon River t Peru (H. W. Webb). 



The wax-like texture of this species is unusual in the group, 

 although equally thin species inhabit Argentina. The inornate sur- 

 face, straight (or even convex) columellar edge, and very narrow 

 umbilicus are other characteristic features. 



