CONTRIBUTIONS 



TO THE 



TERTIARY FAUNA OF FLORIDA, 



WITH ESPECIAL REFERENCE TO THE 



MIOCENE SILEX-BEDS OF TAMPA 



AND THE 



PLIOCENE BEDS OF THE CALOOSAHATCHIE RIVER. 



BV 



WILLIAM HKALEY DALL, A. M ., 

 Paleontologist to the U. 5. Geological Survey, 



Honorary Professor of Invertebrate Paleontology 

 in Wagner Free Institute of Science. 



?A 



PART III. 



A NEW CLASSIFICATION OF THE PELECYPODA. 



