OF NEW SOUTH WALES. 291 



This species closely resembles H. Penolensis, Cox, but differs 

 particularly in its coarser ribbing, in its coloration and by the 

 presence of transverse strias. 



Dimensions. — Diameters '15, and 1-4, height '125 of an inch. 



Habitat. — Among herbage on the slopes of the Cape Nor- 

 thumberland cliffs ; also fossilized in the same rocks which are 

 indurated blown sands of Pleistocene age. Numerous examples. 



Helix arenicola. 



Shell umbilicated, depressly-globose ; spire moderately raised, 

 ornamented with strong and somewhat regular curved stria?, 

 passing into ribs, very minutely transversely striated and 

 granulated ; color semi-transparent horn ; whorls 4|, rounded, 

 gradually increasing, suture impressed ; aperture rounded, entire ; 

 lip simple, columella margin everted ; base convex, slightly 

 shining, striated ; umbilicus broad, exposing all the whorls. 



Seems to have some affinity with H. Microsmos, Cox, but 

 differs in its wide umbilicus ; it closely resembles the European 

 H. rupestris, but the spire is more elevated, the whorls rounder, 

 of smaller size, and the riblets not so coarse. 



Dimensions. — Diameters '085 and '08, Height '065 of an inch. 



Habitat. — About roots of shrubs on the sand-dunes, Holdfast 

 Bay, and Surveyor's Point, Yorke's Peninsula ; and among rocky 

 debris, River Murray cliffs at Mannum. Numerous examples. 



