48 ILLINOIS BIOLOGICAL MONOGRAPHS [48 



protection in most of the river systems. I have taken the species, which is 

 common, in all the rivers except the Menomonee, where it is absent. Of the 

 lakes, the smaller bodies of water likeSkidmore ponds, Laura lake and similar 

 ponds, have their logfish in large numbers, and they also occur to a lesser 

 extent in clear lakes, Oconomowoc, Lower Nashotah, as well. In these 

 latter, however, the fish seem not to attain so large a size. In Oconomowoc 

 lake, I get a great many very small logfish in the shore weeds, yet large 

 ones are rare. They attain a weight of a quarter of a pound or a bit more 

 in the Oconomowoc and Fox rivers, but are not prized as a pan fish — for 

 no particular reason it would seem. The food consists of any animal life 

 that happens to be at hand — fish, crayfish, insects, larvae, mollusca. They 

 bite readily on worms, but rarely on minnows, and put up a fight about 

 equal to that of a goodsized rockbass. The fish spawn in June and July, 

 making shallow depressions in the shallow water near the shore — often in 

 rushes. Here the old fish bravely defends its nest against intruders. So 

 strong is the defense reaction that I frequently have caught the fish on 

 the nest with no other equipment than my hands. The eggs are whitish, 

 and very sticky, lying in the nest in a mass. They hatch in 7 to 9 days. 



67. Lepomis euryorus (McKay). McKay's Sunfish. 



The rarest of the sunfish, known to me only from three specimens 

 taken in Oconomowoc lake, on three different occasions, and always at 

 night. Whether this is significant or not I can not say, as the habits of the 

 species are but little known. These fish came from the north shore of the 

 lake, in water less than a foot deep, over gravel bottom, and were taken in 

 a minnow seine along with Microperca punctulata and Labidesthes siccidus. 

 The largest specimen measures 2\ inches long. 



68. Lepomis humilis (Girard). Orange-spotted Sunfish. 



This tiny little sunfish is also rare in Waukesha county, and has been 

 taken by me only from the headwaters of the Fox river at Lannon where 

 it is associated with Esox americanus and Umbra limi. My largest specimen, 

 2f inches long, was a male in full nuptial coloration, taken July 7, 1920, 

 and is one of the most beautiful of our local fishes. I have not taken the 

 species since this date, and a total of only five specimens has come to hand. 

 The food consists of about equal parts of vegetable and animal matter, 

 being composed of bits of Ceratophyllum, Potamogeton and Elodea, with 

 some algae, together with entomostraca, insect larvae, a few tiny mollusca, 

 and some very small crayfish (Crambarus propinquus). I know nothing 

 of its breeding habits. The fish is so small as to be of no economic im- 

 portance. 



69. Lepomis incisor (Cuv. & Valen.). Bluegill; Sunfish. 



Abundant in all the lakes and streams in the county, and by far the 

 commonest of the true sunfish. In the lakes they are found in deep and 



