THE SOILS OF FLORIDA. 
77 
hatcliee River. These formations, although of marine origin, are 
now found at an elevation of ten to twelve or more feet above sea 
level, indicating that during the Pleistocene the whole area of south¬ 
ern Florida was under water, but during or at the close of this 
period a slight elevation occurred which brought this part of the 
peninsula above water level. That this upward movement was gen¬ 
eral for southern and east Florida is indicated by the elevation of 
the coquina rock as far north as St. Augustine, and by the fact that 
marine shell deposits are found, as previously stated, at various 
localities along and near the east coast and in the St. Johns River 
valley. The beginning of the Everglades dates probably from this 
time. 
Pig. 2.—Sketch map of southern Florida showing progress in 
drainage of the Everglades to May, 1911. 
