CONCHOLOGY. |09 



C. lahyrinthus. The winding Carocolla. 



Species discoid, umbilicaled, with the aperture toothed. 



3. Anostoma. Two species. 

 An extraordinary shell, sometimes called the antique lamp 

 from its form. 



Shell orbicular, the spire convex and obtuse; aperture 

 round, toothed within, grinning, turned upward to the spire ; 

 margin reflected. 



Anostoma depressa. Anostoma globulosa. 



A. depressa. The depressed Anostoma. 



Sub-globular, depressed and sub-carinated in its circumfer- 

 ence, not umbilicated ; aperture rpund, the margin contin- 

 ued by a callosity, toothed, thickened, and turned towards 

 the back of the shell. 



A. globulosa. The globular Anastoma. 



Globose, with two small punctures, one on each side of 

 the lip ; slightly carinated, smooth, and white ; margin re- 

 flected. 



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 oper- 

 culum horny, complete, sometimes calcareous externally. 

 Hehcina Neritella. Helicina fasciata. 



H. striata. H. viridis. 



H. Neritella. The Nerite-shaped Helicina. PI. 1 9, fig. 4. 

 Species yellowisji white, finely striated, the edge reflect- 

 ed in a roll. 



