152 ZONJTES. 



II. NITIDULA, Dnip. PI. 49, figs. 84-8C. 



Widel} 7 umbilicated, globosely depressed, rather smooth, orange- 

 brown above, whitish below, slightly sinning; whorls 4j, the 



last dilated in front. Diam. 9 mill. 



Europe. 



H. nitida, Friele,is a synonym, and H. lucent, Pult., and 11. 

 Jlelmii, Gilb., are slight varieties. 



II. SIMPLICULA, Morelet. PL 49, figs. 81-89. 



Moderately umbilicated, thin, striulate, scarcely shining, 

 diaphanous, light corneous, whitish below ; whorls 5, slowly 

 enlarging, the last subangulated above, suture deepty impressed, 



columellar margin of aperture very short. Diam. 6'6 mill. 



Portugal. 

 H. JACCETANICA, Bourg. PI. 49, figs. 90-92. 



Subperviously narrowly umbilicated, depressed, convex above, 

 shining, fragile, pellucid, corneous, striulate above, more or less 

 smooth below ; whorls 5, slowty increasing, suture well impressed, 

 last whorl scarcely larger, rounded below. Diam. 5 - 25 mill. 



Montserrat, Catalonia. 

 Is perhaps a var. of H. petronella, Charp. 



II. PURA, Alder. PL 49, figs. 93-91. 



Moderately umbilicated, depressed, ashy-white to light corne- 

 ous, crystalline, lightly striate, very obscurely so except at the 

 suture; whorls 4, rapidly enlarging, suture moderate. 



Diam. 3-4 mill. 



With this species has been confounded the following one as 

 well as several of its S3 T nonyms. 



Yar. LENTICULA, Held. (Figs. 95-91 ) Shell corneous. 



H. RADIATULA, Alder. PL 49, figs. 98-100. 



Moderately umbilicated, depressed, pellucid, shining, closely 

 lightly striulate, corneous ; whorls 4, rapid ty enlarging, the last 

 depressed, suture submargined. Diam. 4-5 mill. 



Circumpolar, Europe, Northern Asia, North 



America from Oregon and Great Slave Lake 



to the Gulf of Mexico. 



One of the commonest species of middle Europe and the 

 United States. It has been confounded with the preceding, but 



