NOTES ON EOCENE MOLLUSCA, WITH DESCRIPTIONS 

 OF SOME NEW SPECIES. 



BY 



T. H. Aldrich. 



SUMMARY OF CONTENTS. 



Introduction 3 



Notes AND Remarks on Eocene Species 4-9 



Heilprin's Species Published in 1880 4-6 



Notes on Various Forms 6-7 



The Genus Ringicula in American lEocene De- 

 posits 7-9 



Descriptions of New Species 9-16 



Gastropoda 9-15 



Pelecypoda 15-16 



Explanation of Plates 1 7-26 



-:o:- 



Introduction. 



This brief paper contains descriptions of a number of small 

 species which the writer has had on hand for many years and 

 now publishes at the suggestion of G. D. Harris. Notes on allied 

 forms, and drawings of some species not heretofore adequately 

 figured, are added. Dr. J. C. McConnell has furnished the il- 

 lustrations. 



