TRANSACTIONS OF WAGNER 
VEGETATION OF SOUTH FLORIDA 
158 
comes within 3o dm. (1 foot) of low water level in Rock Creek near Lostmans 
River. In short, outcrops of bed rock are found around the main part of the 
Everglades from Jupiter River to Ft. Shackleford, with no important inter- 
ruption except between Lostmans River and the farthest west of the rocky 
keys beyond Long Key (Everglades). In this break, one of the natural drain- 
age outlets of the Everglades, rock does not on the average lie more than 
3 feet below the level of low water. Sanford* believes that the term sink is 
not accurate, because the area is too large; the rock floor too flat. He 
believes that the Everglades occupy a series of comparatively shallow rock 
hollows, the partial contour of which will be indicated when the soundings 
are given which indicate the depth of the muck. 
The underlying rock is nearly horizontal, dipping slightly toward the south, 
but does not denote any sudden upheaval (Text Fig. 2). Its surface is irregular, 
being full of pot-holes, deep fissures, varied by irregular and jagged ridges and 
seams. It is not stratified, but is homogeneous in character and is rotten, 
porous and susceptible of being easily excavated. This rock foundation was 
at one time the bed of an inland sea, or ancient lake which has been filled in 
its southern part to form the present Everglades. The entire basin has been 
filled to the level of the marginal rims with a deposit of sand and muck, so that 
the surface of the Everglades is now a plane with a gentle slope from north to 
south. On the other hand, Sanfordf suggests that the Everglades owe their 
existence primarily to an abundant rainfall and to the slight elevation of 
southern Florida. He thinks that even if there were no basin structure 
whatever and were the bed rock surface absolutely flat along an east-west line, 
the present rainfall, the sluggish drainage and the luxuriant growth of vegeta- 
tion would result in a marsh forming in the center of the peninsula from Lake 
Okeechobee. In short, he thinks the Everglades resemble in origin the Dis- 
mal Swamp of North Carolina and Virginia. 
Character of the Everglade Soil.—The peat found throughout the larger 
part of the Everglades rests on rock, sand, or marl. In places, soundings indi- 
cate more than one peat bed, with sand between (Text Fig. 2). The relations 
of peat and sand to the bed rock west of Ft. Lauderdale are shown in the ac- 
companying generalized section along the drainage canal, based on data fur- 
nished by J. H. Newman, engineer (Text Fig. 2). The map of the Everglades 
* Sanford, Samuel: Second Annual Report, Florida State Geological Survey, 1909: 192. 
t Sanford, Samuel: Second Annual Report, Florida State Geological Survey, 1909: 193. 
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