220 ENTOMOLOGY 



ally in the pirate perch, the brook silversides, and the stickleback, in 

 which they averaged forty-five per cent. They amounted to about one 

 third the food of fishes as large and important as the red horse and the 

 river carp, and made nearly one fourth that of fifty-one buffalo fishes. 

 They appear further in considerable quantity in the food of a number of 

 the minnow family (Notropis, Pimephales, etc.), which habitually fre- 

 quent the swift waters of stony streams, but were curiously deficient in 

 the small collection of miller's thumbs (Cottidae) which hunt for food in 

 similar situations. The sunfishes eat but few of this important group, 

 the average of the family being only six per cent. 



" Larvae of aquatic beetles, notwithstanding the abundance of some 

 of the forms, occurred in only insignificant ratios, but were taken by fifty- 

 six specimens, belonging to nineteen of the species, more frequently by 

 the sunfishes than by any other group. The kinds most commonly 

 captured were larvae of Gyrinidae and Hydrophilidae; whereas the adult 

 surface beetles themselves (Gyrinus, Dineutes, etc.) whose zigzag- 

 darting swarms no one can have failed to notice were not once en- 

 countered in my studies. 



"The almost equally well-known slender water-skippers (Hygro- 

 trechus) seem also completely protected by their habits and activity 

 from capture by fishes, only a single specimen occurring in the food of 

 all my specimens. Indeed, the true water bugs (Hemiptera) were gener- 

 ally rare, with the exception of the small soft-bodied genus Corisa, 

 which was taken by one hundred and ten specimens, belonging to twenty- 

 seven species, most abundantly by the sunfishes and top minnows. 



"From the order Neuroptera [in the broad sense] fishes draw a larger 

 part of their food than from any other single group. In fact, nearly a 

 fifth of the entire amount of food consumed by all the adult fishes exam- 

 ined by me consisted of aquatic larvae of this order, the greater part of 

 them larvae of day flies (Ephemeridae) , principally of the genus Hexa- 

 genia. These neuropterous larvae were eaten especially by the miller's 

 thumb, the sheepshead, the white and striped bass, the common perch, 

 thirteen species of the darters, both the black bass, seven of the sunfishes, 

 the rock bass and the croppies, the pirate perch, the brook silversides, 

 the sticklebacks, the mud minnow, the top minnows, the gizzard shad, 

 the toothed herring, twelve species each of the true minnow family and 

 of the suckers and buffalo, five catfishes, the dog-fish, and the shovel 

 fish, seventy species out of the eighty-seven which I have studied. 



"Among the above, I found them the most important food of the 

 white bass, the toothed herring, the shovel fish (fifty-one per cent.), and 



