HELIX-HELICELLA. 167 



and rather irregularly ribbed-striate ; white, encircled by interrupted 

 chestnut bands, tinted with buff above and around the umbilicus; 

 the upper surface of the spire radially streaked, having a series of 

 white spots at the suture ; whorls 6, slightly convex, slowly regularly 

 increasing, separated by an impressed suture ; the last whorl slightly 

 dilated, inflated and rounded beneath, abruptly and deeply deflected 

 in front. Aperture very oblique, transversely ovate, lunate ; per- 

 istome acute, subdilated, very distinctly lipped with brown within ; 

 the margins converging hardly joined ; basal and columellar mar- 

 gins slightly reflected. (Kob.*) 



Alt. 12, greater diam. 16, lesser 14 mill. 



Near La Senia, on the salt lake of Oran. 



H. affinior Deb., KOBELT, Rossm. Icon. n. f. iv, p. 91, f. 701. 



This species is very closely allied to H. sebkarum, which occurs 

 with it, but is more globose, more evenly sculptured, always hand- 

 somely banded, and the last whorl is much less widened. 



H. SEBKARUM Debeaux. PL 39, figs. 30, 31. 



Shell rather narrowly and deeply umbilicate, depressed-globose, 

 spire depressed-conoid, the apex minute, violaceous ; dull whitish, 

 here and there tinged with light brown ; chalky ; whorls 6, slowly 

 increasing, separated by an impressed suture ; the upper whorls 

 scarcely convex, regularly and sharply striate ; the penultimate 

 whorl more convex, smoother ; the last whorl dilated, compressed, 

 sculptured with short impressed longitudinal lines, closely and 

 strongly ribbed behind the aperture, abruptly deflected in front. 

 Aperture oblique, rather irregularly ovate-rounded, strongly lunate ; 

 the throat varying from chocolate to roseate; peristome acute, 

 slightly dilated, having a strong yellowish-brown lip within ; the 

 upper margin somewhat straightened, lower and basal well arched, 

 the insertions hardly connected. (Kob.*) 



Alt. 11, greater diam. 18, lesser 15 mill. 



La Senia, on the banks of the Sebcha of Oran. 



H. sebkarum Deb., KOBELT, Rossm. Icon. n. f. iv, p. 91, f. 700. 



In coloration, texture and sculpture most nearly allied to H. lute- 

 ata, but also reminding one of small forms of H. subdentata Fer. 

 (Kob.) 



H. CALIDA Kobelt. PI. 38, figs. 8, 9, 10. 



Shell moderately and deeply umbilicate, depressed-trochiform, 

 angulate, rather solid, but little shining ; sculptured all over with 



