The Three-Toed Horse

The period of deposition of Eocene sediments in the Florida peninsular was followed by a gentle earth movement that resulted in raising a limited portion of the Eocene sea bottom forming an island or islands, while other portions remained submerged. As representative of Oligocene time in Florida there have been recognized three formations. The sediments of this period were for a time quite similar to those of the Eocene, predominately calcareous. This is particularly shown by the limestones termed the Marianna and Glendon.

Toward the close of the period, however, there were evidently some slight shiftings that caused the bringing in of more sandy calcareous deposits to which the term Byram marl is assigned. These more sandy sediments of late Oligocene time might be taken as a precursor of conditions to follow, for the Miocene of Florida is made up of considerably less pure limestone, shell and phosphatic marls, fine grained sands and clays.

The physical characteristics of the several formations making up the Miocene suggest that the sea was becoming shallower and that the shoreline was not far removed. This appears to have been particularly true of the deposits of middle and upper Miocene time. That there were shiftings, or slight movements within and during the period itself is borne out in a study of some of the deposits, especially the different zones in the richly fossiliferous shell marls and in the beds of fuller's earth which are separated by a sandstone stratum. Fuller's earth, as no doubt is generally known, is a variety of clay used in the filtering and refining of mineral, animal and vegetable oils and fats. In the United States it was first commercially produced in Florida in 1895. Since that year Florida has been one of the leading states of the Union in the production of this material.

Phosphatic limestones of this age have very recently proven their commercial value in the production of a pleasing building stone, used most effectively for interior finishes. To this the distinctive trade name of "Floridene Stone" has been given. In addition to the commercial value, the Miocene is also of more than ordinary scientific interest for the reason that the earliest known land mammals not only from Florida but also from the eastern part of the United States have been obtained from these deposits. These include the remains of a flesh-eating mammal related to the recent dogs and wolves, an early rhinoceros, a small camel, a miniature deer-like animal, the commonly called "giant pig", and the three-toed horse. Mention should also be made of the finding of rather complete remains of the early dugong in the deposits containing the beds of fuller's earth in Gadsden County.