The Food of Fishes. 51 



tomostraca from the food, the larger size of the insects 

 taken, and the appearance of fishes and crawfishes. 



Among the insects were a large Hydrophilus unknown 

 to me, but nearly as large as H. triangularis^ the larva of 

 Corydalis cornutus^ of Libellula and of some Ephemerid. 

 The fishes composed about thirty-six per cent, of the food. 

 The only recognizable specimens Avere a small Cyprinoid 

 and a young buffalo-fish {Ichthyohus huhalus). Crawfishes 

 and the river shrimp (Palaemonetes) had been eaten by 

 two of the specimens. 



Lepiopomus pallidus, Mit. Common Sunfish. 



This abundant, hardy and voracious species, is found 

 throughout the state, and may l)e regarded as the typical 

 sunfish. It is most plentiful in the larger rivers in cen- 

 tral Illinois, being replaced in poads by Apomotis cyanel- 

 lus. 



Consistently with its wide range and varied habitat, it 

 is a generar feeder for a sunfish, — peculiar only in the fact 

 of its strictly non-predaceous character. Of forty-five 

 specimens examined, only one had eaten a fish, and that 

 one only a single small darter. 



Undifferentiated Centrarchidce. — I introduce here the 

 food of six specimens of this family which were too small 

 for determination. They were too deep for Micropterus, 

 and as they had but three anal spines, could not have 

 been Ambloplites or Pomoxys. They were probably Lep- 

 iopomus pallidus. All were taken from the Illinois Riv- 

 er, — a part of them near La Salle, in July, 1879, — the 

 others from Peoria, in June, 1878. 



The smallest (seven-sixteenths of an inch long) had 

 eaten only Daphniidse. The next in size (one-half inch) 

 contained Cyclops (ninety-eight per cent.) and Cliydorus. 

 Nearly the whole of the food of the remaining four was 

 Daphniidae (ninety-four per cent.), including Daphnia 

 pulex. 



F od of the Yo ting . 



My smallest specimens, five in number, ranging from 

 three-fourths of an inch to one inch, were taken in August, 



