198 heliciNjE. 



dilated and flattened above; peristome simple, acute, shortly 

 expanded. 



nemoraloides, C. B. Adams. 



Sub-gen. cokyda, Albers. 



Shell imperforate, depressly or conically globose ; whorls con- 

 vex, the last anteriorly deflexed, excavated at the base about the 

 columella; peristome internally somewhat thickened, the co- 

 lumellar margin dilated, reflexed, appressed. 



alauda, Ferus. pudibunda, Beck. 



avellana, Ferus. strobilus, Ferus. 



indistincta, Ferus. Troscheli, Pfeiff. 



Genus ANOSTOMA, Fischer. 



Shell orbiculate ; spire convex, obtuse ; aperture turned 

 upwards, toothed. 



Si/n. Tomogeres, Montf. Angystoma, 8 chum. 



Ex. A. ringens, Limuvus, pi. 77, fig. 8. 



The great peculiarity of Anostoma is the fact of the last 

 whorl taking a sudden turn and bending the aperture up- 

 wards, so as to present it on the same plane; the animal 

 must walk with the spire of the shell downwards resting on 

 its foot. There are about three species known, found only 

 in Brazil. 



carinatum, Pfeiff. ringens, Linn. 



globulosum, Lam. 



Genus LUCERNA, Humphrey. 



Shell depressly lenticular, or orbiculately conoidal, umbi- 

 licus covered or imperforate ; whorls flattened, the last keeled 



