Juday—Quantitative Studies of Fauna in Lake Mendota. 489 
Table 10. Results of the chemical analyses of the different insect 
larvae. The results are! stated in percentages of the dry weight. 
Larva 
Nitrogen 
Crude 
Protein 
(N x 6.25 ) 
Ether 
Extract 
(Fat) 
Crude 
Fiber 
(Chitin) 
Ash 
Chironomus . 
7.36 
46.00 
8.00 
5.76 
5.14 
Corethra . 
10.74 
67.12 
9.45 
6.15 
7.96 
Sialis . 
S.07 
50.44 
18.50 
3.77 
4.86 
Table 11. The first part of this table shows the average number of 
Corethra larvae per square meter of bottom at station II during the 
different months of the year. In all months except January and Febru¬ 
ary the numbers represent averages of two to nine samples . The second 
part gives the averages by months for the five deep-water stations. The 
third part indicates the results for station I. 
Monthly Averages for Station II 
Monthly Averages for Five Deep-water Stations 
1916.... 
8,900 
7,460 
18,600 
13,110 
22,800 
14,250 
1917.... 
17,960 
14,890 
14,700 
13,650 
13,800 
7,480 
7,200 
2,500 
2,060 
1,800 
1918.... 
Monthly Averages for Station I 
1916.... 
7,350 
7,970 
5,850 
4,520 
3,160 
3,350 
8,560 
3,000 
14,700 
6,700 
1917.. .. 
1918.. .. 
14,475 
11,730 
10,970 
9,500 
15,100 
11,310 
5,245 
1,200 
1,175 
1,550 
600 
8,680 
5,020 
