252 



H Fnfi cassis. 



^ ^M^ IUJCCINUM CORNUTUS. LlHtlCEUS. 



Mawe's Linn. pi. 24, /. 1. 



Lamarck has separated these shells from the Genus 

 Buccinum of Linnaeus, for the following reasons: the 

 form of the aperture being longitudinal, straight, and al- 

 most always dentated on the right side; the flattened 

 side of the columella lip forming a very considerable 

 angle at that side, and the canal being abruptly turned 

 towards the back of the shell : these at once distinguish 

 this genus from that of Buccinum, which has only a 

 notch at the base. The spire of the Cassis is seldom 

 much elevated, often interrupted by thickened bands 

 or varices, obliquely placed, having formed the termi- 

 nations or lips of previous apertures, and constituting 

 the distinguishing character of the first section of this 

 genus, the second not possessing any bands. Shell in- 

 flated, columella plaited or wrinkled transversely, ex- 

 terior nodulous or smooth, spire with bands or nodules 

 only; and the canal at the base always abruptly turn- 

 ed towards the back of the shell. They sometimes at- 

 tain a very large size, and in one species the columella 

 lip projects above the spire, giving a flat, ovate, or tri- 



