482 
2. Foot oF Peorta LAKE (WESLEY) TO PEKIN 
4 CHANNEL CoLLEcTIONS, JULY 22 anp Ave. 19, 1915 
WESLEY TO PEKIN 
Number per square yard| Pounds per acre 
Campeloma subsolidum 49.0 147.0 
Lioplax subcarinatum 15.0 18.0 
87.7 224.6 
Vivipara subpurpurea 8.2 41.0 
Pleurocera sp. 15.5 18.6 
Musculium transversum 16.7 16.7 8.3 8.3 
Leeches (small spp.) 61.5 10.4 
Chironomid larvae (small spp.) 50.0 ~ 129.0 7.0 20.9 
Hydropsyche sp. (larva) 17.5 3.5 
Total 233.4 253.8 
4 CoLLecTIons, 4- To 7-FT. Zonn, Aue. 19, 1915 
‘ WESLEY TO PEKIN 
Number per square yard| Pounds per acre 
Campeloma subsolidum 10.5 31.5 
Vivipara subpurpurea 4.5 20.0 22.5 60.0 
Pleurocera species 5.0 6.0 
Musculium transversum 270.0 135.0 
272.5 136.7 
Sphaerium stamineum 2.5 1.7 
Leeches (small spp.) - 55.0 9.3 
56.5 9.6 
Hydropsyche sp. (larva) 1.5 0.3 
“Total 349.0 2063 
