STIZOSTEDION AMEBICAN PIKE-PERCHES 273 



half-way to vent; pectorals 1.8 to 2.1 in head. Scales 12-14, 80-89, 19-25; 

 lateral line usually complete, some pores occasionally extending on caudal 

 fin; scales on cheeks as a rule sparse. 



Although taken by us but thirty-nine times from sixteen 

 localities, and rare except in a few favorable situations where 

 the water is clear and the current swift, this species is generally 

 distributed in Illinois. It is a far-ranging species, of predomi- 

 nant northern distribution, occurring from Hudson Bay and the 

 Saskatchewan River through New Brunswick and New England 

 to the Potomac and north Georgia, and westward through all 

 the Great Lakes and the Ohio basin to Alabama and Minnesota. 

 It is preferably, however, a lake fish, and is most abundant in 

 the Great Lakes, particularly in Lake Erie. 



It is essentially a piscivorous fish, but also feeds, according 

 to Jordan and Evermann, upon crawfishes when in shallow 

 water. Ten specimens examined by us had eaten nothing but 

 fishes, half of them the hickory-shad (Dorosoma) . Minnows and 

 sunfishes were also noticed. From a single wall-eyed pike caught 

 in Peoria Lake, ten specimens of gizzard-shad were taken, each 

 from three to four inches long. As this is a very thin, high fish, 

 with a serrate belly, these were about as large as a wall-eyed 

 pike can easily swallow, and we may, by a very moderate esti- 

 mate of its requirements, conclude that at least six hundred 

 fishes of this size would be required for its maintenance during 

 one year. Reckoning the average life of a pike at three years, 

 the smallest reasonable estimate of food for each pike-perch 

 would fall somewhere between eighteen hundred and three 

 thousand fishes, and a hundred pike-perch such as should each 

 year be taken along a few miles of a river like the Illinois would 

 require 180,000 to 300,000 fishes for their food. Probably no 

 fish in our streams is able to meet so tremendous a demand 

 except the hickory-shad so abundant in the food of this pike 

 unless the European carp, generally introduced since these 

 observations were made, may be an equally acceptable victim. 

 The wall-eyed pike is a swift and vigorous swimmer, capable 

 of overtaking a black bass. 



It reaches a maximum length of about three feet, and a 

 weight of twenty-five pounds, but examples of this size are very 

 rare. According to Jordan and Evermann, it probably does 

 not average more than ten pounds in the Great Lakes. It 

 prefers clear water with a clean and hard bottom, and is not 

 often found in streams or lakes with a bottom of mud. In the 



