376 Wisconsin Academy of Sciences^ Arts, and Letters. 
''stations”, from which quantitative collections were made 
(fig. 1); over 350 quantitative hauls were obtained from 
depths of 0-7 meters from these stations. In addition over 400 
qualitative catches were made from about 30 selected habitats 
in various parts and at various depths of the lake. Thus quali¬ 
tative, quantitative, and ecological data were obtained. 
Observations were made in the field and in the laboratory as 
to the criteria of life in Lake Mendota. To ascertain in what 
respects they differed from those of other bodies of water, col¬ 
lections from the following places were made: 
Merrill Spring, Merrill Creek, Pheasant Branch Creek, Six- 
Mile Creek, Yahara River and Swamps, Yahara Spillway, Ya- 
hara Rapids, and Yahara Canal, Tenney Park Lagoon and 
Pond, University Brook, and Picnic Pond, all lying around 
Lake Mendota; 
Lake Monona, its bays and outlet, the Yahara River; 
Yahara Swamps and Lake Waubesa to the south; 
Lake Wingra and its springs and pools to the north and 
south. 
Each place was visited a number of times in different sea¬ 
sons. Over 1,500 additional collections, some of them quanti¬ 
tative, were made from these various bodies of water. 
To the fourth phase, that of the breeding of unknown forms, 
only little time could be given. In general, the breeding was 
restricted to the species of Lake Mendota, known as well as 
unknown forms, the known ones for verification. Except for 
a beetle larva, all of the commoner species were reared suc¬ 
cessfully. A considerable number of species from other wa¬ 
ters was reared thru some or all of the stages. The waters 
about Madison abound with little known aquatic species, and 
offer a fertile field to the investigator. Each pool, spring, 
swamp, and river contains its quota of species whose stages 
are unknown to science. 
The fifth phase, namely the role of insects in fish food, has 
received considerable attention, thanks to an arrangement 
with Professor Pearse, who very kindly turned over to me the 
contents of fish stomachs examined by him. Over 1,700 fish 
stomachs, representing over 25 species of fish, have been ex¬ 
amined and the insect contents specifically and numerically 
determined. In the study of reciprocal food relations prob¬ 
ably several thousand insect stomachs (Chironomidae, Tri- 
