American Fisheries Society. 161 
have brought the story thus briefly to your attention. The whole 
subject of the gases dissolved in the waters of the Wisconsin 
lakes is being studied by the Wisconsin Geological and Natural 
0 10 15 20 

lO 
15 
20 
30 
F1G. 12—Trout Lake, Sept. 7, 1906. 
History Survey. We began the study last year and the field 
work is continued during the present season. We shall expect 
to publish at an early date a full account of the results of our in- 
vestigations. 
