6 PREFACE BY THE EDITORS. 
In presenting to the public, for the first time, a complete edition 
of Rafinesque, we forbear to express an opinion on the differences 
which have unhappily arisen regarding the adoption of many of his 
generic and specific names. Where the very highest authorities have 
differed so much, it would seem presumptuous in us to make a 
decision. The numerous valuable writings of our author on 
terrestrial and marine Mollusca (universally acknowledged as such, ) 
together with the great interest which has been awakened in his 
descriptions of our Naiades, will doubtless render this volume an 
acceptable addition to Conchological literature. 
Wo. G. BINNEY, 
GEoRGE W. Tryon, JR. 
Philadelphia, May, 1864. 
