480 
3 CHANNEL COLLECTIONS, JULY 28 AND Ave. 19, 1915 
Pror14 NARROWS 
Number per square yard| Pounds per acre 
Campeloma subsolidum 3.3 9.9 
Lioplax subcarinatus 0.6 0.7 
23.2 46.3 
Vivipara contectoides 3.3 16.5 
Pleurocera sp. 16.0 19.2 
Musculium transversum 1.0 1.0 0.5 0.5 
Leeches (small spp.) 11.3 1.9 
13.3 21 
Caddis larvae (small spp.) 2.0 0.2 
Total 37.5 48.9 
4 CHANNEL COLLECTIONS, JuLY 28 AND Ave. 19, 1915 
Lower Lake, Opposite EAGLE PAcKET LANDING 
Number per square yard} Pounds per acre 
Campeloma subsolidum 26.0 78.0 
Lioplax subcarinatus 37.0 44.4 
134.7 391.6 
Vivipara contectoides* 48.2 241.0 
Pleurocera species 23.5 28.2 
Musculium transversum 1.5 7 0.7 
5.0 3.1 
Sphaerium stamineum 3.5 2.4 
Oligochaeta (small spp.) 17.5 0.6 
Leeches (small spp.) 29.0 48.0 4.9 5.6 
Caddis larvae (small spp.) ab 0.1 
Total 187.7 400.3 
* A small number of V. subpurpurea included. 
