146 Wisconsin Academy of Sciences, Arts, and Letters, 
Table 6. Belation of the number of species of Mollusca to the character of 
the bottom in LaTce Winnebago. 
Boulder 
Gravel 
Sand 
Mud 
Vegetation 
22 
35 
40 
23 
25 
Table 7, Comparison of the molluscan faunas of three different lakes. 
Oneida, N. Y.* 
Maxinkuckee, Ind.f 
Winnebago, Wis. 
Unionidae . 
14 
14 
12 
Sphaeriidae . 
27 
41 
35 
Pleuroceridae . 
1 
10 
1 
Amnicolidae . 
11 
4 
9 
Valvaiidae . 
3 
2 
6 
Viviparidae . 
3 
3 
2 
Physidae ... 
4 
2 
6 
Planorbidae . 
10 
7 
12 
Lymnaeidae . 
9 
6 
10 
Ancylidae . 
3 
4 
1 
Total. 
85 
93 
94 
*Baker, 1918. 
tEverman and Olark, 1920. 
