HELIX. 69 



Subsection V. PSEUDOCAMPYL^EA, Hesse. 1884. 



A Grecian group, including species with sub-continuous peristome. 



H. PELLTTA, F4r. Grecian Archipelago. 

 Subsection VI. ELONA, H. and A. Adams, 1855. 



Shell planorboid, spire involute, apex immersed, H. QUIMPERIANA, 

 Fer. Sterna, Albers. 1850 (non Linn.), is a synonym. 



Subsection VII. CHILOTREMA, Leach. 1820. 



Lenticular, strongly carinated, aperture basal, sub-horizontal, 

 transversely oval, the reflected lip continuous, angular. 



H. LAPICIDA, Linn. 



Helicogona, Risso. 1826, Latomus, Fitz. 1833, Lenticula, Held. 

 1837, and Vortex, Moquin-Tandon. 1855, are synonyms. 

 Section III. ARIONTA, Leach, 1820. 



Shell perforate, rather thin, turbinately globose ; whorls 6, convex, 

 peristome lipped, columellar lip dilated near the umbilicus. 



H. ARBUSTORUM, Linn. 



Europe, California. Different as are these habitats the mollusks 

 and shells appear to be intimately related : they are geographically 

 isolated, the whole of the United States east of the Rocky Mountains 

 possessing no representative of the group. 



Section IV. EURYSTOMA, Albers, 1850. 



Narrowly umbilicated, globosely depressed, calcareous ; whorls 5, 

 the last deflected near the aperture, convex below ; peristome widely 

 lipped, its extremities approximating, joined by a callus. H. VIT- 

 TATA, Mull. Ceylon. 



Eyrystoma, Morch. 1852, is a synonym. 



Group IX, ARIONTA, Leach, 1820. 



Section I. LYSINOE, Adams, 1855. 

 H. FIDELIS, Gray. PI. 15, figs. 94-96. 



Moderately umbilicated, rugosely striated with impressed spiral 

 lines, light yellowish or brownish above, lower surface dark chestnut, 

 sometimes uniformly black, with a peripheral chestnut band ; whorls 

 7, rounded ; periphery thickened, simple above, reflected below. 

 Diam. 34 mill. 



Northern California, Oregon, Washington Terr. 

 H. Nuttalliana, Lea is a synonym. 



