— a a 
513 
Mippite oF Duck Lake, Oct. 2, 1914, In PoTAMOGETON PECTINATUS 
WEED Fauna, UPPER 9 IncHES (DeEpruH, 4 FT.) 
No. per sq. yard Pounds per acre 
Valvata spp. 373500 2,062.5 
Amnicola limosa 1,500 55.5 
2,421.7 
Planorbis trivolvis 375 262.5 
Physa (small spp.) 75 41.2 
Chironomid larvae (small spp.) 375 26.2 
| 86.2 
Hyalella knickerbockeri 1,500 60.0 
Total 41,325 2,507.9 
Foot or THompson LAKE, WeEsT Sipe, AvuG. 12, 1914, rn PoTAMOGETON PECTINATUS 
WEED Fauna, UPPER 9 INCHES (DEPTH, 3.5 FT.) 
No. per sq. yard Pounds per acre 
Physa (small spp.) 9,600 528.0 
534.6 
Planorbis (small spp.) 120 6.6 
Caenis nymphs 1,920 153.6 
Agrionid nymphs 2,400 1,200.0 
1,953.6 
Chironomid larvae (small spp.) 6,000 420.0 
Hyalella knickerbockeri 4,500 180.0 
Total 24,540 2,488.2 
