12G Bulletin Wisconsin Natural History Society [Vol. 13, No. 3 
ter part of the day in the country under investigation. These 
trips were not confined to any one time of the day or night, 
though a majority of them were made during the forenoon, 
from 8 to 12 o’clock, and a considerable number of them in the 
early morning, from 5 to 9 o’clock. On these trips, field glasses 
were always carried, and notes of the species of birds and ani- 
mals seen, together with the other necessary data, were made on 
the spot. Wide-necked bottles of alcohol and mason jars were 
found indispensible for collecting small animals. A 44-guage 
double-barreled shot-gun and a camera, together with a long- 
handled water net completed the field equipment. In the labora- 
tory the material collected was assorted and put into vials, 
labeled, and card-indexed for future reference. 
A cknowledgements 
The indoor work was done in the laboratories of the Depart- 
ment of Zoology, University of Wisconsin, under the guidance 
and encouragement of Dr. A. S. Pearse, to whom the writer 
wishes to express his appreciation of the advice and suggestions 
always sq kindly given. To Prof. W. S. Marshall and Mr. 
R. A. Muttkowski the writer is indebted for the determination 
of various species of insects, and to Prof. George Wagner for 
reading the manuscript and offering helpful suggestions. 
II. PHYSICAL FEATURES OF THE INVESTIGATED AREA 
The Lake 
The region selected for investigation lies at the southwest 
corner of Lake Wingra, and about three miles from Madison. 
The lake extends nearly due east and west, and the formation 
where the work was done fronts the lake for a distance of approxi- 
mately one half mile, and extends from the lake in a southerly 
direction for nearly three-quarters of a mile. Within this area 
are found six distinct habitats, or association, namely: the lake, 
marsh, springs, wood, fields, and inland ponds or pools, each 
with its own characteristic biota. It will therefore be advis- 
able to discuss briefly each of these habitats. It should be 
stated that, owing to dredging operations which are at the pres- 
ent time being carried on in various parts of the lake, the forma- 
