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 Ely ton, 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 picblished description already exists, 

 I will cheerfully resign the name I may have given 

 it and "render unto Ceesar 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 

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