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VEGETATION OF SOUTH FLORIDA 



he-huckleberry, Bejaria racemosa Vent, and coontie,Zamia floridanaDC. The 

 tension line is very sharply drawn between the salt marsh and the saw-palmetto 

 land with a few scattered pines. A difference of 30 cm. in level will make a 

 difference in the vegetation. The pure forest of long-leaf pine, Pinus palustris 

 Mill., begins to give way to a mixed forest of long-leaf pine and slash-pine, 

 Pinus caribaea Morelet at Punta Gorda. South of this station, on Charlotte 

 Harbor, the slash-pine becomes more prominent in the forest until it replaces 

 the long-leaf pine almost entirely in the forest, when the Caloosahatchee River 

 is reached, but the forest north of that river is restricted in width by its division 

 into parts by pine savannas, swamps, salt marshes, and wet prairies. Scattered 

 growths of long-leaf pines, Pinus palustris Mill., continue south of the Caloosa- 

 hatchee River into Lee County on the authority of J. A. Davison, an engineer, 

 as far as Surveyor's Creek, and the tree has been reported at Henderson's 

 Creek, but it is not an important element of the forest, which consists of the 

 slash-pine, Pinus caribaea Morelet and associated species. The Caloosa- 

 hatchee River may be taken as the southern limit of the main forest of the long- 

 leaf pine. 



BANANA HOLE ASSOCIATIONS 



The banana holes, so called because dwarf bananas have been raised in 

 them, are limestone sinks, or pot-holes (Plate III, Figs, i and 2). The pres- 

 ence or absence of water is conditioned by the relative rate of evaporation, on 

 the water-table, and on the season of the year. When the rains are heavy, the 

 drainage of the adjoining pineland is into these limestone depressions, while hi 

 light rains, the water finds its way through the porous oolitic limestone rock 

 into underground channels of drainage. These banana holes have originated 

 as shallow depressions in the limestone rock and through the solvent action of 

 rain water containing carbon dioxide, humic acid and various organic acids, 

 the soft lime rock has been gradually eaten away until no oolitic limestone 

 is left in the holes which communicate with underground solution channels 

 formed coincidently with superficial erosion. Next to the surface, bristling 

 with irregular, pointed projections, the most striking feature of the Biscayne 

 pmeland south of Miami is the presence of innumerable holes and hollows, 

 three decimeters to one meter deep and a meter to fifty meters across. A 

 few of these hollows may owe their origin to original conditions of deposition, 

 some may be due to upheaval of rocks by trees uprooted by the wind, while 



