LAKE ZuricH, AucustT—OcToseEr, 1916. 
Bottom Fauna 
13 CoLLEcTIONS, LirroRAL ZONE, 1 To 7 Ft. SOME VEGETATION 
Number per square yard | Pounds per acre 
| 
Campeloma subsolidum Ba Shs! cet 9.9 
Pisidium spp. 21.3 0.8 
Amnicolidae 84.5 190.3 4.6 10.0 
Valvatidae 84. 4.6 
Oligochaeta (small spp.) 3.3 0.2° 
Leeches (small spp.) 6.6 pe 
Chironomid larvae (small spp.) 94.6 13.2 
Palpomyia larvae 6.6 0.5 
Corethra larvae 13.4 | 0.5 
Sand-case caddis larvae 38.7 226.6 Ker 49.2 
Polycentropus larvae 1:5 0.3 
Agrionid nymphs 15 0.7 
Sialis larvae 1.5 0.9 
Hexagenia, etc. (nymphs) 25.3: 22.8 
Hyalella knickerbockeri 33.6 1.3 
Total 420.2 69.1 
CrystaL LAKE, AuGusT—OcTosBeER, 1916. 
Bortom Fauna 
6 CoLLections, LirroraAL ZoNE, 1 To 7 FT. SoME VEGETATION 
Number per square yard) Pounds per acre 
Amnicolidae 
Valvatidae 
Planorbis sp. 
Unionidae, young 
58.5 
58.5 
168.0 
bo bo 
SBS ge 
om 
Chironomid larvae (small spp.) 
Ceratopogon larvae 
Hexagenia, etc. (nymphs) 
Libellulid nymphs 
Gomphid nymphs 
Agrionid nymphs 
Caddis larvae (on Chara) 
Sand-case caddis 
Hyalella knickerbockeri 
SSA tenia a Cora Est Gers, 
SomnMmannonn 
bo 
or 
Total 
508.0 
340.0 
» 
Peg ice, aoe ea ees 
ONrPAIOCA ONO 
= 
or 
a 
~ 
40.4 
