PREFACE 



THE following pages are in continuation of the work on the Tertiary 

 Fauna of Florida which was published in the preceding parts of this 

 volume. As it was thought by persons interested that the title of the work 

 insufficiently indicated its present scope, it has been supplemented by one or 

 two explanatory lines on the title-page. 



When this work was begun the scheme included chiefly a description of 

 the entire invertebrate fauna of the Pliocene beds of the Caloosahatchie, the 

 silex beds of Ballast Point, and other Floridian localities explored by Mr. 

 Joseph Willcox, Professor Heilprin, the writer, and others, with such refer- 

 ences to allied forms as might be necessary for the proper elucidation of the 

 material. 



As time went on, however, the interest aroused by the explorations of 

 the Wagner Institute and its friends, and by the United States Geological 

 Survey in Florida and adjacent parts of the Coastal Plain, resulted in bringing 

 in a constantly increasing mass of material. In particular, the existence of 

 Upper Oligocene beds in Western Florida, containing hundreds of species 

 many of which were new, added two populous invertebrate faunas to our 

 Tertiary series. It was found that a number of the species belonging to these 

 beds had been described from the Antillean Tertiaries. Hence it became 

 necessary, in order to put the work on a sound foundation, not only to review 

 the species of any given group known to occur in the United States, but also 

 to extend the revision to the Tertiaries of the West Indies. 



Owing to the chaotic condition of our Tertiary Paleontology, especially 

 the Post-Eocene faunas, this work has involved an enormous amount of 

 drudgery, occupying the writer's leisure to an extent not anticipated at the 

 outset. It is believed that the results will be beneficial in clearing the way 

 for subsequent students and putting the nomenclature on a more permanent 

 and reliable basis. The clearing up of the stratigraphical relations of many 

 of the older species is quite as important as the description of the numerous 



