INTRODUCTION. 
Whilst residing in the mansion of my kind and 
hospitable friend, Judge T ait, of Claiborne, Alabama, 
where I was employed in collecting the organic 
remains of the vicinity, I occasionally made excur- 
sions up or down the Alabama river, for the purpose 
of procuring fresh water shells. I have succeeded 
in obtaining some species which I believe to be new, 
and hope to fix by accurate delineations and descrip- 
tions. A careful search for all the species inhabiting 
the Black Warrior at Erie, and again in Jefferson 
county, north of Elyton, together with researches in 
the streams of the Tennessee Valley, have furnished 
other species, several of which I presume to be unde- 
scribed. If in any instance I have thus introduced a 
shell of which a published description already exists. 
I will cheerfully resign the name I may have given 
it apd “render unto Csssar the things which are 
Csesar’s;” but where a claim is made upon such 
shells, merely because the descriptions may have 
been read to the members of some institution, I 
