32 UNIVERSITY OF WISCONSIN STUDIES 



Ameiurus melas (Rafinesque), black bullhead 



Nine adults, most of them taken from trot-lines set in the 

 slews joining the lake near its outlet, were examined, June 25 to 

 July 14. Length: 122-282; average 232. Food: fish 13.5; 

 chironomid larvae .9; Helea larvae .4; mayfly nymphs 2.5; 

 Sialis nymphs .6; dragon-fly nymphs .4; caddis fly larvae .6; 

 Leptocerus larvae and cases 1.4; dytiscid larvae .4; Corixa .6; 

 crayfish 29.5; Hyalella .5; Daphnia 9.9; Chydorus .1; Eury- 

 cercus .9; Leptodora 2.5; ostracods .1; Planorbis 2; plants 2.5; 

 Arcella-like seeds .3; filamentous algae 19.9; diatoms 8.4; des- 

 mids .6; sand .4; mud .6. One specimen contained no food. 



On July 7 a young specimen was caught in a dip net. It 

 measured 37 mm. in length and had eaten: chironomid larvae 

 25; Ceriodaphnia 20; Cyclops 50; ostracods 5. 



Ameiurus natalis (Le Seur), yellow bullhead 



Ten adults were examined on July 6 and 8. Length: 234- 

 417; average 285. Food: fish 57.8; crayfishes 26.1; Daphnia 2.6; 

 ostracods 1.1; Planorbis .5; brow seeds 2.2; filamentous algae 

 2.2; sand .2; unknown 6.7. One specimen contained no food. 



Ameiurus nebulosus (Le Seur), speckled bullhead 



Three adults, caught in slews on trot-lines, were examined on 

 July 7 and 10. Length: 258-306; average 286. Food: a nestling 

 bird 15; minnows 11.7; midge pupae 1.7; insect remains .3; 

 crayfishes 38.8; ostracods .2; Valisneria 33.3; fuzzy discoidal 

 seeds .1. 



Five young individuals caught at the margin of a slew with 

 a dip net were examined on July 7. Length: 27-36; average 31. 

 Food: chironomid larvae 18; water mites 1; Hyalella .4; Cerio- 

 daphnia 27; Eurycercus 8.6; Chydorus 6.2; Alona .6; Bosmina 

 7.4; Cyclops 16.4; ostracods 13; sand 1.4. 



Boleosoma nigrum (Rafinesque), Johnny darter 



Ten specimens of this little darter were examined; June 29 

 to July 9; all being caught with a seine on sandy beaches. 

 Length: 26-50; average 34. Food: chironomid larvae 78; Helea 

 larvae 3; a maggot 2; Cyclops 3.5; ostracods 13; sand .5. 



