■ The Productivity of Fish Food in Oneida Lake 131 



Table No. 33. Population of Vkgetation, Habitat No. CXXVI 



Mollusks 



Ancyltts parallclus 4 specimens 



Associated animals 

 Hirudinea 



Glossiphonia fiisca 2 



Trichoptera 



Caddis-fly larva I 



Dipt era 



Chironomid larvae 2 



5 specimens 



The total animal population of the .submerged and floating 

 vegetation as calculated for the 1916 survey, aggregates 

 9,463,428 mollusks and 355,954 associated animals, a total 

 population of 9,819,382. It is probable that a far greater 

 animal population occupies the area covered by the vegetation 

 than is here indicated. The unit areas are too few (a total 

 of 10) in number to include the entire area- as v^as done w^ith 

 the bottom fauna, the units of which were much more numer- 

 ous. As stated on a previous page, the results of the survey 

 of vegetation were somewhat unexpected, the amount of Hfe 

 falling short of that recorded for the animal life among the 

 plants of the outlet at Brewerton in the fall of 191 5. It is 

 possible that the extensive use of the vegetation in the outlet 

 may be due to the lateness of the season or perhaps to the 

 difference of location. A study of this phase of the subject 

 in Lower South Bay at different seasons would help to solve 

 the problem. 



In connection with the use of the higher plants as food by 

 invertebrate animals, the results of investigations on Potoma- 

 togen by Moore ('15, p. 284) are of interest. Sixteen species 

 of animals were found on 9 species of plants and the majority 

 of animals were observed to eat the tissue of the plants. The 

 groups observed were as follows : 



