SOME FLORIDA LAKES AND LAKE BASINS.

tahoochee formation or the Tampa formation. The drain from the lake as it approaches the sink passes through a narrow gorge cut in this limestone.
About one-half mile farther south (Sec. 14) another sink is found. This third sink receives the flow from Mill Creek, a small stream draining considerable territory lying south of the Seaboard Air Line Railway and east of Lloyds.
During a season of excessive rains these sinks are unable to carry away the water. Under these conditions the overflow from Lake Miccosukee as well as from 'Mill Creek ultimately findL- its escape by flowing to the south-west past Lloyds to the St. Marks River.
The surface in Miccosukee Basin is covered with muck to a varying depth. Borings put down near the north end of the basin, out from the margin of the drain, indicated the presence of muck for a depth of from six inches to one foot. Beneath the muck in this part of the basin was found a gray sand. This sand is underlaid, at a variable depth, by the usual red sandy clay. At the south end of the lake the sand is largely absent, (the muck which is from one to three or more feet deep resting, so far as observed, directly upon the red clay.
Lake M,iccosukee probably represents a basin developed by solution near the headwaters of streams originally tributary to the St. Marks River. Previous to the formation of Miccosukee Basin the drainage of this part of the country doubtless passed through small streams, to the south past the present village of Lloyds, -thence to the Gulf through the St. Marks River. The lake basin since its formation has enlarged to the north-west, the lowest part of the basin now being found near the sink in the north-west corner.
Mill Creek which now enters from the south and disappears through a sink a few miles north of Lloyds illustrates the reversal of flow of a stream due to the formation of a sink- This stream, previous to the formation of the sink, flowed south-west to the St. Marks River. At the present time it flows north and enters the sink. At times of excessive rainfall the sink is unable to carry off the water and the stream under these conditions flows in its earlier course to the St. Marks River.
ALLIGATOR LAKE.
Alligator Lake lies in the central part of Columbia County, from one and a half to two miles southeast of Lake City. The lake basin has a total area of about I,OOO acres. Numerous smaller lakes occur to the west and north of this large lake. ,The stur-

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