The Food of Young Fishes. 73 



No very small Labracid^e were found, the youngest being 

 a Morone an inch and a quarter long. Half of the food of 

 this consisted of Entomostraca (chiefly Cladocera), and 

 the other half was minute gizzard-shad. 



A group of forty- three sunfishes (Centrarchida?), from 

 iive-eighths of an inch to two inches long, was made up as 

 follows : — of five specimens of Micropterus under three- 

 fourths of an inch long, two of Ambloplites of the same 

 size, two of 01ia?nobryttus from seven-eighths of an inch 

 to one inch, one of Apomotis an inch in length, nine of 

 Lepioijomus from an inch to an inch and a fourth, nine of 

 Eupomotis from one and a half to two inches, five of Oen- 

 trarchus one inch and under, four of Pomoxys from three- 

 fourth of an inch to an inch and a half, and six indeter- 

 minable specimens, probably Lepiopomus, from seven- 

 sixteenths to five-eighths of an inch long. Ninety-six per 

 cent, of the food of these forty-three specimens consisted 

 of Entomostraca and larvcie of Chironomus, — seventy of 

 the first and twenty-six of the second, — the trivial remain- 

 der consisting of Neuroptera larvae and young Amphipoda 

 with traces of water mites, Corixas and mollusks (the last 

 in Eupomotis). The Entomostraca were forty-two per 

 cent. Cladocera, nineteen per cent. Oopepoda and nine per 

 cent. Ostracoda. 



A single Haploidonotus an inch and an eighth in length, 

 had eaten Chironomus larvct^ (seventy-five i)er cent.) and 

 larvcie of Palingenla hilineata. 



EsociD^. 



I did not have the good fortune to obtain any young of the 

 common pike, and can only report on the food of a single 

 Esox salmoneus an inch and a fourth in length. This speci- 

 men, taken at Pekin, 111., on the 2d of June, had already 

 ])egun its life labor of the elimination of little fishes, these 

 making al)out two-fifths of its food. The remainder con- 

 sisted of Crustacea, composed about equally of young Am- 

 phipoda, Daphniidiie and Lynceid*. The presence of so 

 large a quantity of these minute Entomostraca in the stom- 

 ach of a pickerel of this size, is sufficient evidence that 

 they form the principal part of its food at an earlier age. 



