187 



sent genus. He had imagined that the shells with a plait- 

 ed column, the aperture without any notch at the base, 

 and the margin smooth and sharp, were river shells; and 

 consequently had formed them into a genus by them- 

 selves, under the name of Conovulus; but, from the sub- 

 sequent observations of M. de Valenciennes, it was dis- 

 covered that they were terrestrial. Lamarck has there- 

 fore united all of the G. Conovulus under the present 

 name. Shell suboval, or oblong; aperture longitudi- 

 nal, contracted, and ear-shaped, quite entire at the base; 

 the margin at the upper part narrowed and disunited, 

 columella with one or more callous plaits; the centre of 

 the right lip thickened, sometimes reflected outwards, 

 and sometimes smooth and sharp. 



Right Lip outwardly reflected. 



Auricula Midae Auricula scarabaeus 



Judae bovina 



Sileni caprella 



leporis myosotis 



felis minima. 



Right Lip plain and sharp. 



Auricula Dombeiana Auricula nitens 

 coniformis monile. 



