208 HELICINiE. 



Sub-gen. corilla, H. and A. Adams (Atopa, Alters, not 



Fabr.). 



Shell often sinistrorsal, widely umbilicated, discoidal, plane 

 above, convex at the base ; last whorl compressed at the side, 

 anteriorly defiexed ; peristome thickened, reflexed, the margins 

 joined by an elevated callus emitting a strong re-entering 

 lamina. 



achatinum, Gray. refugum, Gould. 



erroneum, Alters. Pdvolii, Desk. 



Genus IBERUS, Montfort. 



Shell usually depressly conoidal, umbilicus open or 

 covered ; whorls flattened, often exserted, the last with a 

 keel or an acute margin ; aperture lunate, angular, colu- 

 mellar margin callous, more or less reflexed, appressed. 



Syn. Helicogena, Risso. Trochidea, Brown. Leuco- 

 chroa, Beck. Turricula, Beck. Anomalia, MiihJf. Obelus, 

 Hartm. Trochula, Schltit. Crenea, Albers. Tectula, 

 Lowe. Discula, Lowe. 



Ex. I. Gualterianus, LinnceM, pi. 78, fig. 4. Shell, I. 

 Gaulterianus, fig. 4, a. 



This extensive group is widely distributed, being found in 

 Spain, Sicily, Corsica, Malta, the Canary Islands, the 

 North Coast of Africa, Egypt, Syria, and Madeira. The 

 species of Macularia are from the south of Europe ; 

 Campylcea is almost entirely an European group, being found 

 in Spain, France, Savoy, Dalmatia, Illyria, and the Greek 

 Islands ; the species of Thea and JEyista are from Birmah, 

 China, Loo-Choo, Japan, and the Island of Luzon. The 

 only species of Hclicigona known is a native of the British 

 Islands. 



