64 B TRANSACTIONS OF THE WAGNER FREE 



which give us the first unequivocal evidences of the existence of a marine 

 Pliocene formation in the United States east of the Pacific slope, have 

 been fully detailed in the narrative (pp. 27-31), and only require inci- 

 dental mention in this place. They appear in most places as a partially 

 indurated marl or earthy limestone, of a yellowish, buff, or white color, 

 and either largely destitute of organic remains, or so densely charged 

 with them as to constitute a pure shell-rock. At their first visible out- 

 crop, about twenty miles by water above Fort Myers, they barely reach 

 water level, but they gradually rise higher and higher, until some twenty 

 or twenty-five miles below Fort Thompson, their elevation reaches (or 

 reached at the time of our visit) fully six to eight feet, and this elevation 

 is maintained throughout a considerable part of the nearly continuous 

 exposure of some twelve or fourteen miles that immediately precedes 

 the Fort Thompson rapids. At this locality they, in company with the 

 overlying Post-Pliocene Venus bed, disappear beneath the heavy capping 

 of Fort Thompson fresh-water limestone, fully described in the narrative, 

 but there can be no question that their inward extension is still very 

 much greater. 



Inasmuch as the deposits in question have been traced to a point 

 removed by fully 40-50 miles in a direct line from the sea, or to a position 

 one-third across the State, they afford the most conclusive evidence, if 

 any such were still needed, of the utter fallaciousness of the theory that 

 seeks to explain the formation of the peninsula on the assumption of 

 successive coral growths. They, moreover, clearly indicate that one of 

 the last chapters in the history of the formation of the State was practi- 

 cally identical with the series of closing chapters that rounded off the 

 physical history of the eastern border of the United States generally 

 steady sedimentation, slow and gradual upheaval, and absence of specially 

 disturbing forces which might otherwise have interfered with the regular 

 processes attending local organic evolution. 



