Pietenpol—Visible Spectrum of Wisconsin Lake Waters 589 
To the same general type belong Turtle lake (rated at 93) 
with the Bog Hole near Trout lake (rated 45), Allequash lake, 
Swamp near Trout lake, Nemahbin. The last three were not 
examined for color. 
In a similar way the absorption curves seem to show that the 
color of the following waters are due to a mixture of stains 
somewhat similar to each other and different from that which 
dominates the former set of lakes. 
Fig-. 13. Mean curves for lakes of second type. 6. Devils, Green, 
Marl; 14. Pine, Mouse, Silver. Also unrated lakes. B. Bass 
lake; R. Round lake, 1915; S. lake Superior. 
Table 7 
Color Lakes 
6-8 _ Devils, Green, Marl. 
14___ Mouse, Pine, Silver. 
The absorption curves of this type are not as similar as those 
of the first set; but they show a general agreement, as inspec- 
