322 FISHES OP ILLINOIS 



nois than in either of the other sections, and about equally 

 frequent in the Illinois River and in the Mississippi. 



In its general distribution it contrasts strongly with its com- 

 panion species, the white bass, the latter being northern in its 

 range and the present species southern. It occurs throughout 

 the Mississippi Valley northward to the latitude of Cincinnati 

 and St. Louis, southward to New Orleans, and westward to the 

 Kansas River. Its most northerly localities in this state are 

 Green River in Henry county and the Illinois River at Ottawa, 

 in La Salle county. 



This fish reaches a length of twelve to eighteen inches and a 

 weight of one to five pounds, although it does not ordinarily 

 exceed a pound or two. It is common in the market catches at 

 Havana, Meredosia, and Peoria, but hardly ever of a weight of 

 more than half a pound. The catch of the yellow and the white 

 bass together from the Illinois River in 1899, made up, no doubt, 

 mainly of the present species, amounted to 92,931 pounds. It 

 takes live bait readily, and will rise to the fly, and is considered 

 by some anglers as scarcely inferior to the black bass as a game 

 fish. It has been introduced by the State Fish Commission of 

 Pennsylvania into several of the rivers of that state. 



What little is known of its food indicates an insectivorous 

 habit, adults feeding on aquatic larvae, especially those of May- 

 flies, together with small crustaceans and terrestrial insects. 



The yellow bass spawned in May at Havana in 1899. 



FAMILY SCUENIDJC 



THE DRUMS 



Body compressed, more or less elongate; scales thin, usually ctenoid; 

 head scaled; lateral line continuous, extending on caudal fin; skeleton osseous; 

 vertebrae 22 to 32 (about); ventrals thoracic, I, 5; dorsals confluent or sep- 

 arate, the spines depressible into a more or less perfect groove; anal spines 

 1 or 2; caudal usually not forked; no mesocoracoid ; gill-membranes separate, 

 free from isthmus; branchiostegals 7; pseudobranchise usually large, present 

 in most genera; gill-rakers present; preopercle serrate or not; opercle usually 

 ending in 2 flat points; mouth small or large; premaxillary protractile; no 

 supplemental maxillary; chin usually with pores, sometimes with barbels; 

 no teeth on vomer, palatines, pterygoids, or tongue; no incisors; lower pha- 

 ryngeals separate or united, the teeth conic or molar; ear-bones or otoliths 

 very large; pyloric caeca usually rather few; air-bladder usually large and 

 complicated (occasionally wanting); special drumming muscles developed in 

 abdominal wall of many species, their function being to produce sounds by 

 the impact of their vibrations on the air-bladder. 



