4-8 
The Food of Fishes. 
pi bottom., near Bird’s Point, Missouri. Two of these, 
one inch long and under, taken in September 1879, had 
eaten only Bosmina longirostris and Cyclops. Insect 
food first appears in specimens one and one-half inches 
long. Eight specimens, between one and three inches 
long, six of which were taken from a lake in the Illinois 
bottoms, near Pekin, in October, 1879, and two from a 
lake in Kentucky, near Cairo, Illinois, had eaten about 
forty per cent. Entomostraca, thirty per cent. Neurop- 
tera larvae, and thirty per cent. Corixas and Diptera 
larvae. Daphnia pulex, Simocephalus americanus, Bos- 
mina longirostis , Chydorus, Pleuroxus and Cyclops, were 
among the Entomostraca. Corixa alternata was found 
among the Hemiptera. Most of the Diptera (i. e., fifteen 
per cent.) were larval Chironomus. 
Food of the Adult. 
Six adults from rivers, streams and lakes in central 
and southern Illinois, show the usual change in food, 
carried farther than in the preceding species. Entomos- 
traca disappear — except a few Chydorus in a single spec- 
imen — and fishes become the principal reliance, amount- 
ing to forty-seven per cent, of the food. Corixas, larvae of 
Palingenia bilineata, and some terrestrial Coleoptera — 
Anomala binotata — which made half the food of one 
specimen, are the remaining items. 
The especially piscivorous habit of this species is 
probably related to the size of its mouth, which is much 
the largest among the sunfishes proper. A similar rela 
tion has already been noticed between the two black bass. 
