200 IIELICINiE. 



Simson, Pfciff. strangulata, C. B. Adams. 



sinuata, Mull. tridentata, Ferus. 



soror, Ferus. valida, C. B. Adams. 



Sub-gen. labtrinthus, Beck (Lyrostoma, Swains.). 



Shell orbicular, depressed, convex on both sides, last whorl 

 carinated, deflexed at the aperture, scrobiculate externally; aper- 

 ture auriform, ringent; peristome continuous, free, the margins 

 united as far as the umbilicus by an intermediate, cord-like 

 callus, which emits a descending lamina, in the middle, to the 

 inner lip. 



annulifera, Pfeiff. leucodon, Pfeiff. 



auriculina, Petit. otostoma, Pfeiff. 



bifurcata, Desk. plicata, Bom. 



Dunkeri, Pfeiff. quadridentata, Brod. 



isodon, Pfeiff. Tamsiana, Dlcr. 



labyrinthus, Chem. uncigera, Petit. 

 Leprieurii, Petit. 



Sub-gen. isomerta, Albers. 



Shell with the last whorl constricted at the umbilicus ; peri- 

 stome widely expanded ; aperture with two acute teeth, one on 

 the middle of the peristome, the other on the inner lip. 



atrata, Pfeiff. Oreas, Koch. 



faunus, Phil. 



Sub-gen. dentellaria, Schumacher (Lucidula, Swains.). 



Shell imperforate, very rarely umbilicated, solid, globose or 

 conically globose, last whorl anteriorly deflexed, often angu- 

 lated; aperture coai'ctate, often ringent ; peristome thick, ex- 

 panded, the margins variously dentate or tuberculose. 



auridens, Rang. badia, Ferus. 



