63 



readily discerned that the rate of growth was practically the 

 same at each station — about one inch per day. Growth 

 ceased in the latter part of June or early July, when a height 

 of between 90 and 100 inches was reached. Certain differences 

 which the curves present, and which may be due to variations 

 in the depth of water, exposure, or other causes, would be a 

 study in themselves, and will not be considered here. 



This association furnishes the optimum conditions for 

 several birds. About its edges, especially around the ponds, 

 a majority of the Redwings hang their nests. The Coot, 

 the Florida Gallinule, and the Least Bittern are more restricted 

 to this habitat than are any of the other birds. The Virginia 

 Rail and Sora, although showing no very marked preference 

 for this habitat over the following, will be considered here. 

 The Marsh Wren nests here in greater abundance than in the 

 shore-line association, and occasionally the American Bittern 

 also is found. 



Of the mammals, there are none restricted to this habitat. 

 The Weasels {Mustela novehoracensis and M. cicognanii 

 cicognanii) and the Mink (M. vison vison) find here their best 

 foraging ground, although they prefer the presence of a few 

 fallen trees or stumps. Here one may find piles of fish skulls, 

 amphibian bones, and the wings and feathers of marsh birds, 

 which tell of the part played by these animals in the ecology 

 of the marsh. Because of the absence of open water, the 

 conditions here are not quite suited to the needs of the Musk- 

 rat. Frequently, however, by the clearing away of the roots 

 of the cat-tails for the construction of its houses, small ponds 

 are formed and the conditions of associations I and II are 

 thus created. The Meadow Mouse is abundant here, and 

 its nests are built just above the water line. Its habits in 

 this environment are so different from its habits on the dry 

 uplands, that its adaptations would be a study in themselves. 



So far as forage is concerned, the cat-tails offer none except 

 the insects they shelter. Of these, the most important are 

 the weevils, the adults of which furnish a large part of the 

 food supply of the Redwing at all seasons of the year. 



