292 IN LOWER FLORIDA WILDS 



a sea passage existed across the State from lower 

 St. John's River to Tampa Bay. If true we have 

 an answer but the present contour of the land does 

 not very well support the channel theory. 



We do know positively that during early or 

 middle Pleistocene time a considerable subsidence 

 of the State of Florida took place. Dr. E. H. 

 Sellards, formerly our State Geologist, has kindly 

 outlined for me a map showing the shore line of 

 the peninsula after the subsidence. It lay a short 

 distance east of Bradentown, passing south into 

 De Soto County, thence east (just north of the 

 Caloosahatchee River) and northward in about 

 the center of the present State. In a general way 

 the territory east of the St. John's was submerged 

 though there were a couple of long islands in that 

 region. The ocean reached north along the south- 

 ern part of the State almost to the 27th parallel, 

 and as the climate was cooler than at present the 

 opportunity was furnished for migration of Atlan- 

 tic forms into the Gulf. 



Everywhere along the banks of the Disston and 

 other drainage canals in the Everglades the soft 

 excavated Pleistocene rock is filled with the same 

 marine shells now living on the west coast. One 



