MuWwwski—The Fauna of Lake Mendota. 
387 
from the lake. Enemies, behavior, and other factors may in¬ 
fluence the complex and distribution of the fauna, but usually 
in combination with one of the major factors already discussed. 
PART II. QUANTITATIVE AND QUALITATIVE SUR¬ 
VEY OF MACROFAUNA 
In the following pages I have not attempted to give the de¬ 
tails of the quantitative work. In all of the tables I have merely 
noted the final averages. Thus, if a species occurred in 20 out 
of 50 catches, the latter number was used to average it, and 
from this the total has been computed. In a number of instan¬ 
ces, however, the total average was so obviously inconsistent 
with the actual representation, that the totals had to be revised 
and raised or lowered arbitrarily, according to the findings 
of the qualitative catches. This was especially the case with 
the Hydroptilid caddisflies. These occur in the lake^^'Tor a very 
short period. But since it was impossible to visit all of the 
stations during the time of their maximum, the final averaged 
total was proportionately much too low. Hence a lower num¬ 
ber was used as a basis for average for these and some other 
species. In general, however, the averaging was strictly ad¬ 
hered to. 
The Macroflora of Lake Mendota 
Because of their importance as a substratum and as a food 
supply, it seems advisable to give a list of the larger plants in 
the lake. I am indebted to Professor Denniston for the use of 
certain tables showing the distribution of the plants in Lake 
Mendota. The following is a list of the species taken: 
1. From Shore line and Rachion. 
Cladophora glomerata L. 
2. From Plant Zone. True lake species which are quite gen¬ 
eral in their distribution. All are submerged plants. 
Potamogeton pectinatus L. 
‘ ‘ zosteraefolius Sebum. 
richardsonii Bennett. 
‘ ‘ lucens L. 
alp inns Balbis (a rarer species). 
“ amplifolius Tuckerm. 
