STROPHOCHEILUS-BORUS. 35 



S. PACHYCHILUS Pfeiffer. PI. 12, figs. 63, 64. 



Shell ovate-oblong, whitish, rather solid ; whorls 4-44, the apical 

 one planorboid ; nepionic shell of 2 2 whorls, spirally striated, some 

 of the stride beaded, distinctly crenulated at the suture ; post-nepio- 

 nic whorls 1 , not regularly crenulated at suture, wrinkle-striate, finely 

 spirally granulated or with the granulation obsolete. Aperture 

 ovate, white within; peristome isabelline, the ends approaching; 

 outer lip slightly expanded and very much thickened on its face ; 

 columella regularly concave ; umbilical chink narrow. 



Alt 35, diam. 20 mill. ; alt. of aperture 2(H mill. 



Questa de Arenas, Huasco, Chili (Bridges). 



Bulitnus pachychilus PFR., P. Z. S. 1842, p. 186 ; Symbols ii, p. 

 48 ; Monogr. ii, p. 46 ; Conchyl. Cab. p. 251, pi. 68, f. 6, 7. PHIL. 

 Abbild. u. Beschreib. i, p. 57, pi. 1, f. 14. MARTENS, Novit. Couch, 

 v, p. 22. 



The thickened lip and obsolescence or irregularity of the cren- 

 ulation of the suture on last whorl, distinguish this species from its 

 nearest ally, S. crenulatus. The nepionic shell moreover, is not 

 evenly spirally striate as in crenulatus, but has larger, granulated, 

 spirals at intervals, with smooth finer ones between them. It in- 

 habits a dry region, and is doubtless a modification of the rosaceus 

 and crenulatus type. 



S. BRLDGE8I Pfeiffer. PL 2, figs. 4, 5, 6. 



Shell slender, elongated-ovate, rather thin light brownish with 

 usually a fleshy tint on the spire. AVhorls 4, the upper two form- 

 ing a smoother but delicately spirally lirulate nepionic portion, first 

 whorl sinking at the obtuse apex, sutures deep, smooth, becoming 

 shallower on later whorls. Post-nepionic whorls 2}, densely but 

 rather obsoletely decussate-granulate. Aperture ovate, over half 

 the shell's length, oblique ; peristome flatly reflexed, wide, whitish, 

 thin, the ends converging, connected by a short but usually rather 

 heavy, thin-edged whitish parietal callus; columella utterly foldless, 

 dilated above, vaulted over the moderately large umbilicus. 



Alt. 20*-22, diam. 11 J mill.; aperture, alt. 12 mill. 



Province Huasco, Chili (Bridges). 



JS. bridgesi PFR, P. Z. S. 1842, p. 186 ; Symbols ii, p. 4:} ; Con- 

 chyl. Cab. pi. 68, f. 10, 11 ; Monogr. ii, p. 47. PHIL., Abbild. u. 

 Beschreib. i, p. 58, pi. 1. f. 15. 



