PREFACE. xv 



of forming new genera, as suggested by 

 certain modern conchologists. 



Considerable alterations have likewise 

 been made in the descriptions at the head 

 of each genus, which, being founded on a 

 minute examination and comparison of 

 species, it is hoped may render the tech- 

 nical definitions more clear and satisfac- 

 tory, and less difficult to be impressed 

 upon the memory. 



In the list of descriptive terms, the Latin 

 word has been prefixed to the English 

 translation or derivative; because it may 

 occur to ladies, or to others who follow, 

 as an amusement, the pursuit of collecting 

 and arranging shells, and who may be 

 unaquainted with the dead languages, to 

 wish for a reference to some Latin author. 



