INSECTS IN RELATION TO OTHER ANIMALS 28 1 



also the raccoon, which is to some extent insectivorous. 

 Monkeys are omnivorous but devour many kinds of insects. 



With these hasty references, we may pass at once to the 

 subject of the insect food of fishes and birds. 



Insects in Relation to Fishes. Insects constitute the 

 most important portion of the food of adult fresh water fishes, 

 furnishing forty per cent.' of their food, according to Dr. 

 Forbes, from whose valuable writings the following extracts 

 are taken. 



' The principal insectivorous fishes are the smaller species, 

 whose size and food structures, when adult, unfit them for the 

 capture of Entomostraca, and yet do not bring them within 

 reach of fishes or Mollusca. Some of these fishes have pecu- 

 liar habits which render them especially dependent upon insect 

 life, the little minnow Phenacobius, for example, which, ac- 

 cording to my studies, makes nearly all its food from insects 

 (ninety-eight per cent.) found under stones in running water. 

 Next are the pirate perch, Aphredoderus (ninety-one per 

 cent.), then the darters (eighty-seven per cent.), the croppies 

 (seventy-three per cent.), half-grown sheepshead (seventy- 

 one per cent.), the shovel fish (fifty-nine per cent.), the chub 

 minnow (fifty-six per cent.), the black warrior sunfish (Chceno- 

 bryttus) and the brook silversides (each fifty-four per cent.), 

 and the rock bass and the cyprinoid genus Notropis (each 

 fifty-two per cent. ) . 



''' Those which take few insects or none are mostly the mud- 

 feeders and the ichthyophagous species, Amia (the dog-fish) 

 being the only exception noted to this general statement. 

 Thus we find insects wholly or nearly absent from the adult 

 dietary of the burbot, the pike, the gar, the black bass, the wall- 

 eyed pike, and the great river catfish, and from that of the 

 hickory shad and the mud-eating minnows (the shiner, the fat- 

 head, etc.). It is to be noted, however, that the larger fishes 

 all go through an insectivorous stage, whether their food 

 when adult be almost wholly other fishes, as with the gar and 

 the pike, or molluscs, as with the sheepshead. The mud- 



