The Productivity of Fish Food in Oneida Lake 47 



other animals. Dawson ('11, \). 29) has shown that this is 

 sometimes the case with the fresh-water puhnonate gastropods, 

 none being present where the vegetation had completely occu- 

 pied quiet, pond-like bodies of water. The submergent type of 

 vegetation is of the greater value, providing support and food 

 for animals, aerating the water, and affording shelter for fish 

 and other animals. Many of these plants remain green 

 throughout the winter. The emergent type of vegetation is of 

 value, although secondary to that of the submergent type. The 

 water-lilies afford shade for fish. 



Description of Characteristic Plant Habitats 



Lower South Bay is very rich in plant life, the majority of 

 the species being abundant. In most of the habitats the plants 

 grow in such a manner as to form dense masses, resembling, 

 in miniature, the heavy forests of the land areas. The aquatic 

 vegetation, which alone is here considered, is of two types, 

 emergent and submerged, the former usually bordering the 

 shore while the latter extends into the deeper water. No 

 attempt was made to study the flora exhaustively, only the 

 plants immediately associated with the animal habitats and the 

 conspicuous plants of the shore margin were collected or noted. 



The vegetation may be considered under five heads, arranged 

 according to the character of the habitat, i, low, swampy 

 shores, well protected, mud bottom ; 2, low shores partly pro- 

 tected, clay or sand bottom ; 3, pond-like areas ; 4, sandy or 

 rocky, exposed shores; and 5, the submerged habitats. 



I. Low, Swampy Shores, well Protected. This type of 

 habitat contains such plants as Black Willow and Buttonbush 

 which live on the shore, and Cat-tails, American Bulrush, Bur- 

 reed, Arrow-heads, Pickerel-weed, Duck-weeds, and Loose- 

 strife,* which occupy the- shallow water bordering the shore 

 vegetation. A few species of submerged plants, such as 

 Elodea, Najas, Myriophyllum, and the Pond-weeds Potamoge- 



* The scientific names of these plants will be found in the list of 

 species at the end of this chapter. 



