SECTION X. 



191 



Genus i. Cylindri emarginati, or fuch 

 whofe edge is quite even and fliarp. And 



Genus 2. Cylindri marginati, or fuch 

 whofe edge is not fharp and fmooth, but 

 has a very thick border, which turns over 

 into a very prominent ledge on the back, 

 like to the Helmets. 



The fpecies of this family are many, 

 and very beautiful Shells, 



The twelfth family of the Univalves is 

 the Voluta or Volute. It is very nume- 

 rous in its fpecies, and is the family which, 

 for richnefs and beauty of colouring, fur- 

 paffes all the other families of the Uni- 

 valves, and is reckoned the ornament or 

 capital objedl of coUedions. , The far 

 greater number of Volutes always bear a 

 value ; fome kinds, as the Admirals, &c. 

 have fetched furprizing prices when per- 



fed 



