CONTRIBUTIONS 



Tertiary Fauna of Florida, 



WITH ESPECIAL REFERENCE TO THE 



MIOCENE SILEX-BEDS OF TAMPA 



AND THE 



PLIOCENE BEDS OF THE CALOOSAHATCHIE RIVER. 



BY 



WILLIAM HEALEY DALL, A. M , 



Paleo7itologist to the U. S. Geological Survey, 



Honorary Professor of Invertebrate Paleontology 

 in Wagner Free Institute of Science. 



PART III. 



A NEW CLASSIFICATION OF THE PELECYPODA. 



