262 FLORIDA- GEOLOGICAL SURVEY-THIRD ANNUAL REPORT.
and vary so much in appearance, that it is hardly worth while to attempt any general statements about their vegetation, except that grasses and other plants with very narrow leaves always make up the bulk of the vegetation where it is undisturbed. Just why these places are treeless is one of the numerous unsolved problems of Florida geography.
In the northern part of the state shallow depressions in the pine woods almost invariably contain a rather dense growth of trees, as in the cypress, gum, and mayhaw ponds, or more bushes than trees, in which case they are known as bays.
CYPRESS PONDS.
(PLATE 23.1)
Cypress ponds are very abundant in the West Florida limestone region and East Florida flatwoods, and frequent in the northern parts of the Gulf hammock region and South Florida flatwoods, but rare in the lake region and south of latitude 280. They are of various sizes and shapes, but usually approximately circular or slightly elliptical and from one to a hundred acres in extent. In wet weather the water in them may be as much as three feet deep in the middle, while in late spring they are usually dry or nearly so. and it is not an uncommon occurrence for fire to burn through them as it does through the surrounding pine forests. This being the case they are of no importance as sources of peat, but they are of considerable scientific interest as representing a distinct and not very widely distributed (only from South Carolina to Mississippi) type of vegetation.
I have not closely examined any of the cypress ponds of the Gulf hammock region except in winter, but they do not seem to differ much from those in other parts of the state. The following list is made up from notes taken in Jackson, Columbia, Baker, Duval, Clay, Bradford, Alachua, Putnam, St. John's, Orange, Osceola and Pasco Counties.
TREES
Taxodium imbricarium (pond cy- Nyssa biflcra (black gum)
press) Gordonia Lasianthus (bay)
Pinus Elliottii (slash pine) Magnolia glauca (bay)
SMALL TREES OR LARGE SHRUBS
Ilex myrti/olia (yupon) Ihex Cassine (swamp holly)
Nyssa Ogechte (tupelo gum) Cyrilla racemiflora (tyty)
Myrica cerif era (myrtle)