462 Illinois State Lahoratory of Natural History. 



The food of this species as represented by these thirteen 

 specimens, is unusually simple for a catfish, consisting chiefly 

 of bivalve mollusks, larvae of Chironomus and Hexagenia, dis- 

 tillery slops, and accidental rubbish. Fishes are conspicuous 

 by their absence, only a single specimen exhibiting any trace 

 of them. 



Sphserium and Unio made about a fourth of the food, and 

 aquatic insect larvse amounted to one half (Hexagenia thirty- 

 five per cent, and Chironomus fourteen). A hydrophilid and 

 a few terrestrial insects, a few specimens of Vivipara and a 

 Physa, sialid larvae (taken by two), slender leeches eaten by 

 five, and a trace of Potamogeton in one, are the minor ele- 

 ments of this record. One of the specimens, taken in Novem- 

 ber, had eaten eighteen leeches, which made one fourth of its 

 food. It will be noticed that three fourths of the food con- 

 sisted of bivalve mollusks and insect larvae, 



Leptops olivaris, Raf . Mud Cat; Yellow Cat; MoRGA]sr Cat. 



Common in the deeper waters of the larger streams. Ob- 

 tained by us only from the Illinois, Wabash, and Ohio. 



This is one of the largest of the river catfishes, repulsive 

 in appearance, but above the average as food. It is reported 

 by fishermen to feed only upon animal food — chiefly fishes — 

 and such was the case with the two specimens examined from 

 collections made at Quincy in August, 1887. These had fed 

 upon the common river sunfish (Lepomis), several cyprinoids, 

 and an Amiurus four inches long. 



NoTURUS GYRiNUS, Mitch. 



This little catfish, the most abundant of the small species 

 of the family, occurs throughout Illinois, but has been con- 

 fined in our collections mostly to lakes, rivers, and large creeks. 

 It is not by any means restricted to rocky situations, but seems 

 rather to prefer the muddy parts of both the rivers and lakes 

 in which it occurs, 



Thirteen specimens were secured at Pekin and Peoria, 

 from Clear Lake in Kentucky, and from the Fox River in 

 McHenry county. Their food was wholly animal, with the 

 exception of a trace of Algae found in two. This group 



