I 



GEOGRAPHY OF CENTRAL FLORIDA 1/9 



poses; and it is hard to draw the Hne between this and some of 

 the low hammocks ah'eady mentioned. 



Salt marsh muck. Along both coasts, in places protected from 

 wave action by outlying or projecting land masses or the shallow- 

 ness of the ocean bottom, are strips or patches of salt or brackish 

 marsh, characterized by coarse grasses and rushes. The soil, a fine 

 silt or muck, would probably be cjuite fertile if it could be raised a 

 few feet above sea-level, but being saturated with salt water twice 

 a day (or all the time in tideless lagoons), little can be done with it. 

 And the marshes of central Florida are doubtless less fertile 

 than those near the mouths of muddy rivers farther north, as shown 

 by the prevalence of the evergreen rush, J uncus Roemerianus, rather 

 than the marsh grass, Spartina glabra, which has larger leaves and 

 renews them every year. 



MISCELLANEOUS SOILS 



Beach and dune sands. On the exposed portions of both coasts, 

 except the greater part of that bordering the Gulf hammock re- 

 gion, the sand has been piled by waves and wind into beaches and 

 low dunes, which are always more or less calcareous, owing to the 

 presence of fragments of sea shells. The sand is usually rather fine, 

 but contains very little silt or clay. Besides numerous mollusks, 

 crustaceans, etc., that live before high tide level, a few gophers 

 and ants make their homes in the beach sand, but salamanders are 

 absent. The available chemical analyses (O, P, Z) seem to indicate 

 that this soil is fairly well supplied with potash and other ingre- 

 dients of fertility, but it is practically worthless for agriculture, 

 on account of its instability, porosity, and lack of organic matter. 



Shell mounds. As already indicated under the head of topog- 

 raphy, these are found in many places along the coast and navi- 

 gable rivers. They consist mostly of shells of oysters and other bi- 

 valves, one kind of shell usually outnumbering all the rest in any 

 one mound. The shells are usually little broken, and therefore 

 contribute little to the soil, which is usually a thin layer of humus, 

 with no sand or clay visible, though some of the mounds have con- 

 siderable sand mixed with the shells. The vegetation seems to be 

 always hammock of some kind, and on the east coast is usually de- 

 cidedly tropical in composition, south of Cape Canaveral at least. 



Limestone cliffs and caves. Outcrops of tolerably pure and 



