FREE INSTITUTE OF SCIENCE 



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VEGETATION OF SOUTH FLORIDA 



It will be noted that five of the species enumerated above have been placed 

 as both water and animal distributed. With abundance of water, as in times 

 of inundation, they are carried by water currents; with a less amount, or no 

 water at all, they are probably carried by animals. A consideration of four 

 of these plants follows. The saw-grass, Cladium eff usum, has obovoid achenes, 

 somewhat corky at the summit. The buttonbush, Cephalanthus occidentals, 

 has small fruits at length splitting from the base upward into two to four 

 closed, one-seeded portions. The false loosestrife, Isnardia natans, has a many- 

 seeded capsule, while the mermaid-weed, Proserpinaca platycarpa, has a bony, 

 three-angled, three-seeded, nut-like fruit. Where the water is in motion, these 

 plants, along with Sagittaria lancifolia, undoubtedly have their fruits distributed 

 by water currents, and perhaps they have been carried from banana hole to 

 banana hole in seasons when the pineland was flooded with water, or they have 

 fallen to the mud of these shallow water pools and have been carried away 

 incased in the mud on the feet, beaks, and feathers of ducks, herons, swal- 

 lows, and other frequenters of such wet places. 



HAMMOCK VEGETATION 



The examination of the vegetation of the banana holes has suggested the 

 possible origin of the hammocks which form such a conspicuous element in 

 the landscapes of South Florida. The moisture content of the soil plays a 

 most important part in the distribution of the plants. The typic everglade 

 species are aquatic plants; the typic pineland species grow in extremely dry 

 soil during the dry season, while the vegetation of the banana holes and 

 hammocks is decidedly mesophytic, but the character of the hammock is 

 conditioned upon the water content of the soil. We can distinguish, therefore, 

 two kinds of hammocks, viz., high hammocks (Plate V, Fig. 2) and low ham- 

 mocks (Plate VI, Fig. 2). The high hammocks are found under the conditions 

 of soil and surface described in the foregoing paragraph. The low hammocks 

 .are those which occur along the margins of many lakes and streams (Plate VI, 

 Fig. i) and in some of the low swampy areas not connected with any running 

 water or lakes. These low hammocks appear to have generally more sandy 

 soil than the high hammocks. 



