82 College of Forestry 



but merely forage there when there is Httle or no sunHght " 

 is interesting, and may be true for small bodies of water, but 

 not for larger ones, w^here these animals have been observed 

 to crowd the algse or other plants on the surface, in direct 

 sunlight,, even during the hot days of summer. This has been 

 noted not only in Oneida Lake but in other lakes. Four genera 

 of Cladocera, three of Copepoda, one of Isopoda, and two of 

 Amphipoda were collected. A few nymphs of Ephemerida 

 and Odonata were noted as well as one genus, Corisa, of 

 Hemiptera. Larvae of Diptera, especially Chironomus, were 

 abundant, though, curiously enough, mosquito larvae were nota- 

 bly rare. Several larval beetles as well as adults were col- 

 lected, among them Hydroporiis, Creniphilus, and Helophorus. 



The dominant or principal forms of this algal community 

 are, among the algae, Spirogyra, Mougeotia, and Zygnema, 

 which constitute the " blankets." In Oneida Lake, Cladophora, 

 Spirogyra, and Qidogoniuni were the dominant genera. Among 

 the larger animals Cyclops and the larvae of Chironomus were 

 most abundant. Quantitative valuations of the animals of 

 these pools would be of value for comparison with those of 

 Lower South Bay. 



As stated by Piatt ('15, p. 761) "the population of the 

 ' blanket-algae ' has its producers and its consumers, its hunters 

 and its hunted, each readily exchanging roles as occasion de- 

 mands," and the same condition has been shown to be true, 

 on a larger scale, of the Oneida Lake algal communities. The 

 significant fact brought out in this study, as in the investiga- 

 tions made at Lower South Bay, is that the presence of fila- 

 mentous algae in abundance profoundly affects the animals, 

 providing a food supply of sufficient amount to meet the 

 requirements of a large population of herbivorous animals, 

 which, in their turn, provide for the predaceous animals of 

 the habitat. 



The conditions necessary for the abundant growth of algae 

 are admirably met in Lower South Bay, and as a result the 

 algal flora is abundant in both species and individuals, the 

 entire bottom of the bay being covered with plants of this 

 group. Not only the bottom, but the higher vegetation itself 



