188 
BULLETIN OF THE BUREAU OF FISHERIES 
The following table gives the amounts of dissolved organic nitrogen and carbon 
found in the several waters: 
Table 2 . — Dissolved organic nitrogen and carbon in lake water 
[In milligrams per liter of lake water] 
Depth, 
in 
meters 
Date 
Residue 
N 
C 
Ratio, 
N: C 
LAKES 
Mendota 
0 
Oct. 18,1922 
152.0 
0.438 
4.00 
n 9.i 
Do 
0 
Dec. 5, 1922 
176.2 
.484 
7.95 
1:16.4 
Do - 
0 
Feb. 28,1923 
183.0 
.554 
6.31 
1:11.4 
Do - 
0 
July 24,1923 
135.0 
.407 
7.36 
1:18.1 
Do 
0 
Sept. 21, 1923 
129. 1 
.372 
4.48 
1:12.1 
Do - 
0 
Oct. 24,1923 
126.3 
.289 
5. 96 
1:20.6 
Do 
0 
Apr. 23,1924 
119.5 
.335 
5.89 
1:17.6 
Do - - - 
0 
June 18,1924 
169.0 
.307 
5. 58 
1:18.2 
Do — 
20 
Julv 21,1922 
136.7 
.314 
4. 84 
1:15.7 
Do 
20 
Sept. 26, 1922 
162.8 
.304 
4. 69 
1:15.4 
Do - 
20 
Feb. 28,1923 
166.5 
.559 
6. 14 
1:11.0 
Do 
20 
July 24,1923 
129.2 
.404 
5. 85 
1:14.5 
Do - 
20 
Sept. 21, 1923 
131.0 
.376 
5.72 
1:15.2 
Do - 
20 
June 25, 1924 
172.1 
.357 
6. 37 
1:17.8 
.393 
5. 80 
1 : 15. 2 
0 
Dec. 20,1923 
30.8 
.426 
9.41 
1:22.1 
Devils - - - 
0 
July 11,1923 
46.6 
.219 
3.02 
1:14.0 
Do 
0 
Oct. 27,1923 
33.3 
.302 
4. 02 
1:13.3 
Geneva 
0 
July 16,1923 
114.0 
.337 
4. 52 
1:13.4 
Green - 
0 
July 18,1923 
143.7 
.310 
3.95 
1:12.8 
Do 
0 
Oct. 16,1923 
138.0 
.296 
6.51 
1:22.0 
Kegonsa 
0 
July 20,1923 
101.4 
.730 
7. 33 
1:10.0 
Madeline 
0 
Dec. 12,1923 
59.5 
.455 
5.26 
1:11.6 
Michigan 
0 
Feb. 28,1924 
96.4 
.143 
3.24 
1:22.7 
Monona - 
0 
Juno 28, 1923 
141.9 
.712 
7. 92 
1:11.1 
0 
July 6,1923 
132. 6 
.550 
8.20 
1:14.9 
Turtle 
0 
Jan. 18,1924 
66.3 
.490 
13. 22 
1:27.0 
Waubesa - 
0 
July 20,1923 
107.2 
.744 
7.11 
1: 9.6 
Wingra - 
0 
June 26, 1923 
199.9 
.722 
9.52 
1:13.2 
RIVERS 
Wisconsin 1 
0 
July 30,1923 
82.9 
.487 
15.23 
1:31.3 
Do - 
0 
Nov. 21, 1923 
85.1 
.394 
9.85 
1:25.0 
Yahara 3 
0 
July 6,1922 
684.0 
.372 
9.58 
1:25.8 
1 At Prairie du Sac Dam. 3 Above Lake Mendota. 
Of the lakes listed in the table, Monona, Waubesa, and Kegonsa are in the same 
chain as Mendota. Wingra is a small and shallow lake about 1 mile south of Mendota. 
It is largely surrounded by marsh. Rock Lake is about 22 miles east of Madison, 
Green Lake is about 55 miles north, and Geneva Lake is about 57 miles southeast of 
Madison. All these are typical hard-water lakes of southeastern Wisconsin, ranging 
in depth from Wingra (3 meters) and Kegonsa (12 meters) to Mendota (24 meters), 
Geneva (43 meters), and Green (68 meters). Wingra is the smallest of this group 
(about 1 square mile); Geneva has an area of 8.8 square miles; Green has 11.5 
square miles; and Mendota has 15.2. Devils Lake (360 acres) is the only soft-water 
lake in southeastern Wisconsin, occupying a drift basin in the gorge of the quartzites 
of the Baraboo Range, about 30 miles northwest of Madison. Bass, Turtle, and 
Madeline Lakes are small soft-water lakes or lakelets of northeastern Wisconsin. 
Full statistics for all of these lakes may be found in Bulletin XXVII of the Wisconsin 
Geological Survey (Juday, 1914). The Wisconsin River traverses the State from 
north to south, carrying a high-colored water with low mineral content; the Yahara 
is the stream connecting the Madison lakes, and its water is much like that of the 
