58 
The Food of Fishes. 
per cent, of the food, and Entomostraca of the order 
Ostracoda (Cyprids), twenty-six. As both these iare 
found most abundantly in muddy bottoms, it is evident 
that the fish is, at least at first, a bottom feeder. Traces 
of mollusks appear thus early, as well as a few Ephem- 
erid larvae (five per cent.). The remainder of the food 
was insects * eggs and Daplmids — chiefly Simocephalus 
americanus — (twelve per cent.). Chydorus was found in 
five specimens, but in too small quantity to figure in the 
averages. 
Five specimens were studied between two and three 
inches long. In these the same food characters continue, 
modified somewhat by the introduction of larger objects. 
The Chironomus larvae stand at forty-four per cent., and 
the Cyprids at eighteen per cent. Fourteen per cent, ot' 
Allorchestes and eleven per cent, of Neuroptera larvae 
are the only important elements remaining. Two per 
cent, of young TJnios were noticed. Nearly half of the 
food of two larger specimens, between two and three 
inches long, consisted of mollusks — chiefly Physa. A few 
Chironomi and about equal quantities of Ephemerid 
larvae and Allorchestes were all the remaining food. 
Entomostraca therefore disappear at this point. 
Food of the Adult. 
Forty-six per cent, of the food of the nine adults con- 
sisted of Mollusca, including Planorbis, Amnicola and 
Valvata tricarinata, and six per cent, of undetermined 
bivalves. 
The insect food was twenty per cent, of the whole. 
Crustacea twenty-two per cent., and vegetation twelve 
per cent. Half of the last was Chara, and the remainder 
chiefly Myriopliyllum and Algae. The Crustacea were all 
Allorchestes and Asellus. The insects included a trace of 
Chironomus larvae and a few water-beetles (Hydrophili- 
dae), and the usual Neuroptera larvae, among which case- 
flies of the genus Leptocerus were noticed. 
Not a trace of fishes was found in the stomachs of these 
specimens ; and this fact, together with the large percent- 
age of inolluscan food, constituted the leading alimentary 
peculiarities of the species. 
