HELIX ELEVATA. 



DESCRIPTION. 



Shell pale horn-color ; spire elevated : ivhorls seven, re- 

 gularly rounded: umbilicus none: aperture somew^hat 

 angulated : labrum dilated, reflected, pure w^hite at base 

 and pressed to the body whorl, abruptly narrovv^ed on the 

 inner edge beneath the middle, arid continuing thus nar- 

 rowed to the superior termination, leaving a projecting 

 angle behind the middle : labium with a large, robust, very 

 oblique, subarquated, pure white tooth. 



SYNONYMS. 



H. ELEVATA, Nob. Joum. Acad. Nat. Sc. Vol. 2, p. 1 54. 

 H. Knoxvileina ? Feruss. Tabl. Syst. p. 33. 



OBSERVATIONS. 



This shell occurs not unfrequently in many parts of the 

 Western States. When descending the Ohio with Major 

 Long's exploring party I first observed it in the vicinity 

 of Cincinnati. It is related to thyroidus, Nob. by the 

 tooth on the labium ; but this tooth is much more rubust ; 

 it differs more essentially by its much more elevated spire, 

 and by the supeiior half of the dilated lip being abruptly 



