54 



agencies or otherwise, before hatching, and in 3 the young 

 were destroyed before leaving the nest. Seven of the re- 

 mainder were watched to maturity. 



In addition, more or less complete notes were kept on many 

 nests in other parts of the marsh. Besides the observations 

 made in charting these nests, almost daily observations for 

 two seasons were recorded on the migrating birds, especially 

 as they came into the marsh in the evening and left in the 

 morning. Days were spent in studying their actions through 

 binocular field glasses, and for hours at a time individual nests 

 were watched and photographed from a blind at arm's length. 



A discussion of the environment from the standpoint of the 

 plant societies will be considered first. Other phases, includ- 

 ing seasonal changes, will be taken up in connection with 

 corresponding stages in the life history of the bird. Although 

 the zonal arrangement of these societies is best observed 

 about the large ponds in the marshes at the north end of 

 Cayuga Lake, it may be traced quite easily along the Cove 

 and in places along the head of the lake. 



I. The Open-water Association. 



This association, which extends throughout the open and 

 deeper waters of the marsh, is characterized by a number of 

 species of algse and potamogetons which cover the bottom 

 even in the deepest parts. In the shallower portions such 

 plants as Elodea^ Myriophyllum, and Utricularia predominate. 

 The more important plants included in this environment are 

 the following: 



Castalia odorata (Ait.) Woodville & Sweet-scented Water- 

 Wood Uly 



Ceratophyllum demersum L. Hornwort 



Elodea canadensis Michx. Water-weed 



Heteranthera duhia (Jacq.) MacM. Mud Plantain 



Lemna minor L. Duckweed 



Lemna trisulca L. Duckweed 



Marsilea quadrifolia L. European Marsilea 



Myriophyllum spicatum L. Water Milfoil 



