Juday—Quantitative Studies of Fauna in Lake Mendota. 493 
Table 17. Live 'weight and dry weight of the various forms found in 
the intermediate zone of Lake Mendota. These results are hosed on thes 
averages numbers indicated for the 8 - - 20 - meter region in table 16, with 
the ' exception of Corethra. The figures given for Corethra larvae are 
based upon the April crop. The live weights of Pisidium and Sialis were 
not determined, and they are not included, therefore, in the total under 
live weight. Compare with table 15. 
Live Weight 
Dry Weight 
Kilograms 
per 
Hectare 
Pounds 
per 
Acre 
Kilograms 
per 
Hectare 
Pounds 
per 
Acre 
Oligochaeta . 
24.5 
21.8 
4.6 
4.1 
Pisidium ... 
2.7 
2.4 
Sialis ... 
0.8 
0.7 
Ohironomus .. 
141.4 
120.1 
22.8 
20.3 
Corethra .. 
186.4 
166.3 
16.0 
14.3 
1.1 
Protenthes . 
7.3 
6.5 
1.3 
Total... 
359.6 
320.7 
48.2 
42.9 
