50 HELIX. 



*** 



H. KRAUSSI, Pfr. PL 10, fig. 30. 



Moderately umbilicated, closely striate, brownish corneous, suture 

 well impressed; whorls 4J; rapidly increasing, the last wide, sub- 

 depressed, deflected in front; peristome simple, acute, columellar 

 margin dilated, reflected. Diam. 29 mill. 



Cape of Good Hope. 



Var. ft. Smaller, thin. Diam. 21 mill. 



H. MARCESCENS, Cox. PL 10, figs. 28, 29. 



Narrowly umbilicated, thin, translucent, a little shining, slightly 

 rugosely striate, and faintly granular, yellowish corneous., with a 

 narrow chestnut sutural band ; whorls 5, slowly increasing, the last 

 wide; peristome acute, the columellar margin dilated and strongly 

 reflected above. Diam. 16 mill. 



Clarence River, N. S. Wales, Australia. 



H. PHYSETA, Ancey. Unfigured. Thibet. 



Group VIII, PLECTOTKOPIS. 



Shell flattened, rather thin, sculpture usually rough, riblike or 

 granular, sometimes with shaggy epidermis, peristome simple, or a 

 little expanded, thickened within, umbilicus wide. 



A group composed of somewhat incongruous elements, charac- 

 teristic mainly of the Chinese and Japanese provinces. The 

 connection with Camsena or Hadra is so close, through some of the 

 species that the separation is rather arbitrary than natural. 



Section I. PLECTOTROPIS, Albers. 1860. 



Shell flat, somewhat lenticular, thin, widely umbilicated, periphery 

 carinate, and shaggy, peristome simple, a little thickened within. 

 Eastern Asiatic. H. MACKENSII, Ads. and Reeve. 



TJiea, Albers, is a synonym. 



Subsection PSEUDIBERUS, Ancey. 1887. 



More coarsely sculptured, peristome thicker and whitish. 

 H. PLECTOTROPIS, Mart. China, Turkestan. 



