58 FLORIDA GEOLOGICAL SURVEY-THIRD ANNUAL REPORT.
The soil in the basoin is prevailingly a gray sand usually darkened by the presence of organic matter. At a depth of from one to two feet the amount of organic matter is reduced, the sand being lighter in color. Sandy clays are reached as a rule at a depth of from two and a half to three feet.
During a season of normal rainfall this basin is occupied by a lake having a -total area of approximately two thousand acres. Following a period of prolonged drought the basin becomes entirely dry, water remaining only at the sink. In times of excessive rainfall the lake overflows at the east end, the water discharged reaching streams tributary to the St. Marks River.
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4 dt Chaires
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Fig. 3.-Lake Lafayette.
This basin has much the character of an elongated valley. The general course of the streams of this part of the county, the shape of the basin and particularly the topography of the surrounding country indicate that (the drainage of this section was originally through these streams into the St. Marks River. The-formation of sinks diverted the drainage to a subterranean course, the west end of the basin having been reduced to a level somewhat lower than the east end. The further enlargement of the basin is being carried on through the formation of sinks along the border. The largest cf the newly formed sinks is found near the present drainage sink.
LAKE MICCOSUKEE
Miccosukee Basin or Lake Miccosukee lies between Leon and Jefferson Counties, the west border of the lake forming the county line. A small arm of the lake, however, near the north end reaches. into Leon County.