51 



together. It made forty per cent, of the food of the wall-eyed 

 pike ; a third that of the black bass ; nearly half that of the com- 

 mon pike or " pickerel " ; two thirds that of the four specimens 

 of golden shad examined ; and a third of the food of the gars. 

 The only other fishes in whose stomachs it was recognized 

 were the yellow cat, Ictalurns natalis, and young white bass, 

 Roccus. It thus seems to be the especial food of the large 

 game fishes and other particularly predaceous kinds. 



The minnow family (Cyprinidae) are in our waters especially 

 appropriated to the support of the half-grown game fishes, and 

 the smaller carnivorous kinds. They were found in the wall- 

 eyed pike, the perch, the black bass, the blue-cheeked sunfish, 

 the croppie,the pirate perch, the pike, the little pickerel, the chub 

 minnow, the yellow cat, the mud-cat, the dog-fish, and the gar. 



Suckers, Catostomatid?e, I determined only from the pike, 

 the sheepshead, the blue-cheeked '=>\xvi^'^{cyanellus), the yellow 

 cat, and the dog-fish {Amid). Buffalo and carp occurred in the 

 pike, the dog-fish, and the above sunfish. 



The ponds and muddy streams of the Mississippi Valley are 

 the native home of molliisks of remarkable variety and number, 

 and these form a feature of the fauna of the region not less 

 conspicuous and important than its leading groups of fishes. 

 VVe might, therefore, reasonably expect to find these dominant 

 groups connected by the food relation ; and consistently with 

 this expectation, we observe that the sheepshead, the catfishes, 

 the suckers, and the dog-fish find an important part of their 

 food in the molluscan forms abundant in the waters which 

 they themselves most frequent. The class as a whole makes 

 about one fourth of the food of the dog-fish and the sheeps- 

 head — taking the latter as they come, half-grown and adults 

 together — about half that of the cylindrical suckers — rising to 

 sixty per cent, in the red horse — and a considerable ratio (four- 

 teen to sixteen per cent.) of the food of the perch, the common 

 catfishes (Amiurus and Ictalurus), the small-mouthed sunfishes, 

 the top minnows, and the shiner (Notemigonus). Notwithstand- 

 ing the abundance of the fresh-water clams or river mussels 

 (Unio and Anodonta), only a single river fish is especially 

 adapted to their destruction, viz., the white perch or sheeps- 



