The Relation of Mollusks to Fish in Oneida Lake’ 158 
CHAPTER IV. MOLLUSKS AS FOOD FOR FISH. 
excepting the work of Forbes (1878-1888 ), whose studies 
on the food of fresh water fishes were epoch-making, the 
scarcity of literature relating to this important subject is 
noteworthy. Volumes have been published on the taxonomy, 
distribution, commercial importance, and methods of secur- 
ing the fishes of our inland waters, but in the discussion on 
fish-culture, little attention has been given to the subject of 
the food of our native fish. The studies which are recorded 
in the previous pages have shown the amount and character 
of one kind of fish food (the Mollusca) now living in Oneida 
Lake, and its distribution in relation to the aquatic plants 
and to the general physical environment. 
Prof. Forbes recognized the importance of these studies 
when he said (1888, p. 477): “ Among the purely practical 
results to be anticipated, [from the study of fresh water ani- 
mals | are a more accurate knowledge of the conditions favor- 
able to the growth and multiplication of the more important 
species; the ability to judge intelligently on the fitness of 
any body of water to sustain a greater number or a more 
profitable assemblage of fishes than those occurring there 
spontaneously ; guidance as to the new elements of food and 
circumstances which it will be necessary to supply to insure 
the suecessful introduction into any lake or stream of a fish 
not native there; and a clear recognition of the fact that intel- 
ligent fish culture must take into account the necessities of 
the species whose increase is desired, through all ages and 
all stages of their growth, at every season of the year, and 
under all varieties of condition likely to arise. We should 
derive, in short, from these and similar researches, a body of 
full, precise and significant knowledge to take the place of 
the euess-work and empiricism upon which we must other- 
wise depend as the basis of our efforts to maintain the supply 
of food and the incitement to healthful recreation afforded 
by the waters of the State.” 
The fresh-water fishes may be divided into five groups 
according to the dominance of the kind of food: 1, insect 
