491 
5 CHANNEL CoLtections, Auc. 10, 1915 
VALLEY CITY TO KAMPSVILLE 
Number per square yard 
Pounds per acre 
Vivipara subpurpurea 1.0 1.0 5.0 5.0 
Musculium transversum 1.4 0.7 
1.8 1.5 
Young Unionidae 0.4 0.8 
Small oligochaetes 6.2 0.2 
Planarians 2.0 trace 
Hydropsyche larvae 19.0 3.8 
Hexagenia, etc. (nymphs) 0.8 28.8 0.7 5.9 
Chironomid larvae (small spp.) 0.2 trace 
Perlid nymphs 0.2 0.2 
Gomphid nymphs 0.4 1.0 
Total 31.6 12.4 
17 CoLtections, 4- To 7-rT. Zon, AuG. 10, 1915 
VALLEY City To KAMPSVILLE 
Number per square yard 
Pounds per acre 
Campeloma subsolidum | 0.2 0.2 0.6 0.6 
Musculium transversum 12.6 6.3 
: - 14.6 10.3 
Young Unionidae 2.0 4.0 
Small Oligochaeta 4.5 0.1 
Small leeches 0.5 trace 
Planarians 1.0 trace 
Hydropsyche larvae 7.6 19.0 1.5 a rey 
Hexagenia, etc. (nymphs) Bod, Pate 
Chironomid larvae (small spp.) 1.8 0.2 
Gomphid nymphs 0.5 1.2 
Total 33.8 16.6 
