18 Wisconsin Academy of Sciences, Arts and Letters. 
Trout Lake consists of two parts connected by a compara¬ 
tively narrow but deep channel. The south part is about 4 
kilometers (2.5 miles) long and 2.4 kilometers (1.5 miles) 
wide, while the north part is only about half as large. Both 
parts have a maximum depth of about 80 meters (100 feet). 
Samples of water taken at a station in the deepest portion of 
the south part of the lake showed a considerable amount of 
oxygen in the lower water. Half a meter above the bottom, 
where the lake was 29.5 meters deep, the water contained 0.9 
cubic centimeters of dissolved oxygen per liter, and at 27 meters 
there were 2.1 cubic centimeters, which was a little more than 
a third of the amount found at the surface (5.6 cubic centime¬ 
ters). 
Kawaguesaga Lake is very irregular in outline and consists 
of three basins which are connected by rather narrow channels. 
The eastern part is the largest and deepest, having an area of 
about 2.6 square kilometers (1 square mile) and a maximum 
depth of about 18 meters. An examination of the water of the 
eastern portion showed that it contained only a trace of dissolved 
oxygen at 10 meters and none at all at and below 10.5 meters. 
That is, all of the cold, lower water was devoid of free oxygen. 
Gill nets were set in various parts of Kawaguesaga Lake and 
at various depths also, but no specimens of Mackinaw trout 
were obtained. So far as could be learned, also, it has never 
been caught in this lake by fishermen. This seems to indicate 
that conditions here are unfavorable for it. On the other hand, 
six Mackinaw trout were caught in 24 hours when the gill nets 
were set within about a meter of the bottom in the deepest por¬ 
tion of the south part of Trout lake. Ho specimens of it were 
caught, however, when the nets were set in the warm, upper 
water, but only when they were placed in the cool, lower water 
of the deeper portions. The best results, in fact, were obtained 
by placing the nets near the bottom where the water was nearly 
30 meters deep. 
The fishermen stated that the Mackinaw remains in the deep 
water of Trout Lake during the entire summer, and these results 
confirm their observations for late summer at least, and, so far 
as could be ascertained, there is no evident reason why this 
