41] STUDY OF SOUTHERN WISCONSIN FISHES— CAHN 41 



burrows. Their food is anything that may come to hand: they feed 

 almost wholly on animal matter, alive or in any stage of decomposition, 

 fish, crayfish, and any refuse they can find. Notwithstanding, an excellent 

 pan fish. 



46. Ameiurus nebulosus (Le Sueur). Brown Bullhead. 



By far the least common of the native bullheads, taken by me only 

 in Oconomowoc, Ashippun and Laura lakes, in the Oconomowoc river 

 near its entrance into Rock river and in the Pewaukee river near its en- 

 trance into the Fox river, and only sparingly here. They seldom attain 

 a length of more than fourteen inches, and are not ordinarily separated 

 from the preceding species by fishermen. A good table fish, whose diet 

 is entirely animal food, but much less of the scavenger type. 



47. Ameiurus melas (Raf.). Black Bullhead. 



This is an abundant species in all of the soft-bottomed lakes and muddy 

 streams. It is characteristic of small ponds. I have caught dozens in the 

 Skidmore ponds and the small pot-holes near Okauchee lake. They live 

 among submerged vegetation, and a characteristic sight of June and July 

 is the little balls of young bullheads herded about by the adult, up near 

 the surface of the water and along the shoreline. The nests are made either 

 at the base of the weed beds, or under the overhanging banks. The old 

 fish are very solicitous about their young, and attack any small fish that 

 approaches the family school. On being disturbed the little black babies 

 disappear into the weeds in every direction, but soon come together again 

 in deeper water. The smallest of our bullheads, seldom exceeding 6 or 8 

 inches, and hence of little food value. 



48. Leptops olivaris (Raf.). Mud-cat. 



Like Ictalurus punctatus, the mud-cat has recently been introduced 

 from the Mississippi overflows and is thriving in Nagawicka and Ocono- 

 mowoc lakes. There are, apparently, only a few of these large catfish in 

 the lakes, and I have no evidence of their spawning. One of these fish, 

 weighing 16 pounds, was caught on August 7, 1923, in Nagawicka lake, the 

 bait being "night-crawlers." 



49. Noturus flavus (Raf.) Stonecat. 



I have taken this little fish in two localities: the headwaters of the 

 Fox river near Lannon, and the Oconomowoc river at Stonebank. The 

 stonecat is a fish of clear water and fast current exclusively, living under 

 stones in the midst of the fastest riffles and rapids. Habitually headed 

 upstream, the fish are very quick in their movements, and escape almost 

 miraculuously under a minnow sein. The food seems to be entirely ani- 

 mal matter, largely insects and Chironomus larvae, though small mollusca 

 are sometimes found in the stomach. I have twice found in the stomach 

 a considerable number of Planarians. 



