9
6 62 60
o Gainesville
FIGURE 1.-Florida's rainfall is plentiful.
The lines define zones of equal average yearly rainfall, which ranges from 46 to 64 inches. From "Climate and man," U. S. Department of Agriculture yearbook, 1941.
STREAMS IN NORTHERN AND CENTRAL FLORIDA
The area which will be discussed comprises about 22,000 square miles in the north-central part of Florida, including all or parts of 32 of the State's 67 counties. This area consists principally of low coastal lands divided slightly east of center by Trail Ridge, a series of rolling hills that rise no higher than about 200 feet above sea level.
In few other areas of the United States is the distinction between surface water (streams, lakes, and ponds) and ground water more transient. Also, in few other areas is the land surface more obviously drained in part by movement of water underground. The water of a stream or lake may infiltrate through the bed of that stream or lake and become ground water. Elsewhere, perhaps miles