102 College of Forestry 
Floating Pond-weed (Potamogeton Clasping-leaved Pond-weed ( Pote~ 
natans). mogeton perfoliatus). 
Animal life is abundant on the leaves and stems of the 
water plants. 
MOLLUSCA. 
Pseudosuccinea columella. Physa ancillaria warreniana. 
Planorbis campanulatus. Physa gyrina. 
XI. Shallow Creek Type, Moving Water, Muddy Bottom. 
Station XVII. In this type of habitat the water is from 
one to two or three feet deep, the current is not rapid and 
the bottom is composed of mud, usually very fine. In places 
the habitat changes to a rapid stream flowing over a stony 
bottom, but again resumes the still pool type when a basin is 
reached. Three species of mollusks were observed, two of 
them being abundant. 
Elliptio complanatus. abundant. Campeloma decisum, abundant. 
Strophitus edentulus, rare. 
XII. Shallow Creek Type, Rapid Water, Stony Bottom. 
Station XVI.* In this type of habitat the bottom is very 
stony, the water is 6 to 15 inches deep, except in occasional 
quiet pools, the current is swift and the water is clear and 
cold. A typical trout stream. Three types of animal life are 
abundant on the rocks and between and under the rocks. 
MOLLUSCA. 
Ancylus tardus, common. 
CRUSTACEA. 
Crawtish (Cambarus bartoni ro- © Crawfish (Cambarus propinquus), 
bustus), common. common. 
INSECTA. 
Water-penny, beetle larve (Psep-  Caddis-fly larve  (Helicopsyche 
henus lecontev) , common. borealis) , common. 
Caddis-fly cases (Neophylax spe-  Stone-fly nymph (Perla species). 
cies), not common. Stone-fly nymph (Acroneuria spe- 
cies). 
