194 HELICID^E. 



russet ; whorls more than five, with numerous raised, 

 oblique, equidistant striae ; aperture shaped like a horse- 

 shoe ; lip equally reflected, regularly arcuated, describ- 

 ing two-thirds of a circle, with a depression behind its 

 reflection ; within the aperture, on the outer side of the 

 whorl, are two prominent, white teeth, the lower near 

 the base conical, the upper more compressed and placed 

 farther within ; columella with an oblique tooth or fold 

 projecting towards the centre of the aperture, and con- 

 nected by slightly raised, curved lines of callus with the 

 superior and inferior extremities of the lip ; base of 

 the shell showing about one and a half volutions of the 

 spire. 



Greatest transverse diameter more than one-third of 

 an inch, common size less than one-fourth. 



GEOGRAPHICAL DISTRIBUTION. Found hitherto in 

 Illinois, Ohio, Georgia, Alabama, Florida, Kentucky, 

 Tennessee, and Texas. Though not common, it seems 

 to be a widely spread species. 



It is oftenest found in the States bordering upon the 

 Gulf of Mexico. 



REMARKS. This peculiar and interesting shell has 

 been hitherto rare in collections, and is therefore but 

 little known. Some specimens are entirely flat on the 

 upper surface, in some the striae of the whorls are dis- 

 tinct on the upper and lower surfaces, in others only on 

 the upper, leaving the lower surface smooth. The outer 

 whorl is occasionally carinated. The aperture is usually 



