484 
7 CoLiectrons, 1- To 3-rT. Zonr, JuLY 22, 238, 1915 
PEKIN TO COPPERAS CREEK DAM 
Number per square yard) Pounds per acre 
Campeloma subsolidum 92.8 278.4 
Lioplax subcarinatus 5.7 6.8 
108.4 292.4 
Vivipara contectoides 1.4 7.0 
Pleurocera sp. 8.5 10.2 
Musculium transversum 135.7 135.7 67.8 67.8 
Leeches (large sp) edi 11.4 
Leeches (small spp.) 52.8 8.9. 
Small oligochaetes 8.5 0.2 
Asellus sp. 17.1 1.6 
116.8 31.2 
Chironomid larvae (large spp.) 8.5 5.6 
Chironomid larvae (small spp.) 15.7 2.1 
Hydropsyche sp. (larva) veal 1.4 
Young crayfishes 1.4 Not valued 
Total 360.9 391.4 
4. CoPpPERAS CREEK DAM Jo HAvANA 
8 CHANNEL CoLLections, Aue. 3, 19, 1915 
CopPpERAS CREEK DAM TO ONE MILE ABOVE LIVERPOOL 
Number per square yard} Pounds per acre 
Campeloma subsolidum 161.7 485.1 
Lioplax subcarinatus 17.7 21.2 
Vivipara contectoides 63.8 263.4 319.0 874.2 
Vivipara subpurpurea 6.5 32.5 
Pleurocera sp. 13.7 16.4 
Musculium transversum 0.3 0.3 0.1 0.1 
Leeches (small spp.) 18.6 3.1 
Asellus sp. 7.2 28.3 0.6 4.0 
Chironomid larvae (small spp.) 2.5 0.3 
Total 292 878.3 
