488 
22 CoLLections, 4- To 7-FT. Zone, Ava. 2, 5, 6, 27, 1915 
Havana To Lagrance Dam (42.5 Mires) 
Number per square yard |} Pounds per acre 
Campeloma subsolidum 48 144.0 
Lioplax subcarinatus 8 9.6 
Vivipara contectoides or subpur- 73 234.8 
purea 16 80.0 
Pleurocera sp. 1 1.2 
Amnicola emarginata 4 0.1 
88 42.1 
Musculium transversum 84 42.0 
Small oligochaetes 9 0.3 
Small leeches ° 8 1.3 
Asellus sp. 1.5 0.1 
31.1 5.7 
Hydropsyche larvae 7.6 1.5 
Hexagenia, etc. (nymphs) 2.5 2.2 
Chironomid larvae (small spp.) 2.5 0.3 
Total 192.1 
20 CoLLectIons, 1- To 3-rT. Zong, Aug. 2, 5, 6, 1915 
Havana TO Lacrance Dam (42.5 Mites) 
Number per square yard 
Pounds per acre 
Campeloma subsolidum 32.0 96.0 
Lioplax subcarinatus 2.3 Piel 
Vivipara contectoides or subpur- 99.3 385.7 
purea 55.0 275.0 
Pleurocera sp. 10.0 12.0 
Amnicola sp. 2.0 0.1 
91.0 44.6 
Musculium transversum 89.0 44.5 
Small oligochaetes trace 
Small leeches 5.5 0.9 
Asellus sp. trace 
Hydropsyche larvae 4.0 18.3 0.8 5.2 
Hexagenia, etc. (nymphs) 3.0 2.7 
Chironomid larvae (small spp.) 5.8 0.8 
Total 208.6 435.5 
