186 FISHES OF ILLINOIS 



Their mutual rivalries might hence result to their common 

 disadvantage except for a partial avoidance of competition by a 

 difference of local and ecological preference. Our collection 

 data indicate for this species a strong preference for muddy 

 water, its frequency coefficient for streams with a mud bottom 

 being 1.72. Consistent with this fact is its distribution in the 

 lower Illinoisan glaciation. We have found it in all our river 

 basins,, including the Michigan drainage area and the north- 

 eastern glacial lakes, but have not taken it in the extreme north- 

 western part of the state. It has also been absent in our collec- 

 tions from the main streams of the Wabash, the Ohio, and the 

 Mississippi, and from the short creeks of the Mississippi bluffs. 

 It seems with us to be more abundant southward, and has 

 occurred with the greatest frequency in the streams of the 

 Wabash Valley. 



It is generally distributed from Lakes Erie and Huron and 

 the smaller lakes of Ontario to North Carolina and the Florida 

 peninsula, the Alabama River, and Texas. It occurs also in 

 the Arkansas River and up the Missouri to South Dakota. It 

 is one of the commonest and best known bullheads through- 

 out its range. 



As illustrated by the food of a dozen specimens, this species 

 has the habits of a scavenger. One of these fishes had gorged 

 itself with the waste of a fish boat, and one had made the 

 greater part of its last meal from the remnants of a dead cat. 

 Three of these specimens had eaten fishes taken alive, and four 

 others had eaten crawfishes. May-fly larvae and a few water- 

 snails were the only other objects worth mentioning. Seven 

 young specimens, from two to three and a half inches long, had 

 fed principally on Entomostraca, the remainder of their food 

 being chiefly small mollusks and insect larvae. 



This fish is distinguished from the brown bullhead (A. 

 nebulosus) only by the more observant of our fishermen, some of 

 whom call it " greaser" or " slick bullhead," its skin being very 

 thin, and the fish, in consequence, particularly hard to dress. 

 Its maximum weight is !J/ to 2 Ib. 



The yellow bullhead spawned at Havana in May in 1898 

 (Craig). Females with ripe spawn were seen in market at 

 Meredosia on May 24, 1900 (Large). In the words of Dr. 

 Jordan these fishes are "small, but good eating," as we have 

 ourselves proven. 



