Sub-globular, depressed and sub-carinated in its circumference, not umbilicated; aperture round, the margin continued by a callosity, toothed, thickened, and turned towards the back of the shell.
A. globulosa. The globular Anostoma.
Globose, with two small punctures, one on each side of the lip; slightly carinated, smooth, and white; margin reflected.
4. Helicina. Four species.
A terrestrial shell, distinguished from the Helix by its transverse callous columella; depressed and diminished in thickness at the lower part.
Shell sub-globular or conoid, spire low, a little depressed; aperture semi-ovate, modified by the last turn of the spire; the edge of the aperture sharp or a little reflected in a roll, the left edge enlarged at its base in a large callosity, which entirely covers the umbilicus and joins obliquely with the columella, which is twisted and a little projecting; the operculum horny, complete, sometimes calcareous externally.
Helicina Neritella.
H. striata.
H. fasciata.
H. viridis.