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VEGETATION OF SOUTH FLORIDA 



Charlotte Harbor, Pine Sound, San Carlos Bay (at the mouth of the Cal- 

 oosahatchee River) , Estero Bay, and a number of the smaller lagoons. Parts 

 of the mainland, as at Naples and at Horse Point and Chaise Point, are washed 

 by waves of the Gulf of Mexico. South of Cape Romano, the shore line is 

 deeply embayed. Here we find the coast an intricate maze of flats covered 

 with red-mangrove thickets which are intersected with tortuous channels of 

 shallow water. This type of shore line continues to Cape Sable, where sandy 

 deposits take the place of the mud flats. This short geographic description 

 of South Florida will serve as a statement of the position of the most salient 

 features upon the map. 



PHYSIOGRAPHY 



It remains, however, to give a few facts in line with modern physio- 

 graphic study. The coast of South Florida is characterized to a great extent 

 by growing coral reefs, which extend along the coast for over 200 miles and 

 are found nowhere else in the continental limits of the United States. The 

 South Florida mainland has all the aspects of infancy. Drainage is sluggish, 

 lakes, shallow ponds, and sloughs are common. The interior is a marsh and 

 the river systems and stream valleys are not well defined. The short rivers 

 that flow from the Everglades into the Atlantic Ocean are characterized by 

 rapids where they flow from the 'Glades. This aspect of infancy is due, ac- 

 cording to Sanford,* to two operative causes, one the actual recent deposition 

 of the beds, consolidated and unconsolidated, and the other, the slight eleva- 

 tion of the deposits above tide level since deposition. The rocks have had 

 relatively little time to suffer erosion, and this erosion has been delayed be- 

 cause the surface has been too flat to allow clear streams, sediment free, an 

 opportunity to erode valleys and establish well-marked drainage systems. 

 The present Florida mainland, as shown by Dall and others, is the top of a 

 great submarine plateau, the eastern edge of which is near the present shore 

 line, but the western edge extends many kilometers gulfward. The slope of the 

 southern land mass is due to the reaction, or play, of forces between land and 

 water, so that it is inconstant. The shore line topography has a varied look. 

 Its form in places is that of infancy; in other places, of youth, or adolescence. 

 Here and there are found cuspate forelands (projecting capes), fringing sand 



* Sanford, Samuel: The Topography and Geology of Southern Florida. Second Annual Re- 

 port, Fla. Geol. Surv., igog: i7g. 



