200 



WET FOREST COMMUNITIES 



Subterranean-ground stratum: The nymphs of the seventeen-year 

 cicada and the two-year cicada together with earthworms are always 

 numerous. The latter comes out on the ground under a log and ascends 

 under the bark of dead trees during wet weather. 



On the ground one finds slugs (Agriolimax campestris). Under 

 leaves, logs, and bark are snails (Circinaria concava, Polygyra profunda, 



Representatives of the Flood-Plain Forest Animal Communities 



Fig. 151. — A caterpillar (Symmerista albifrons) on the leaf of the soft maple; 

 natural size. 



Fig. 152. — The common land sowbug (Porcellio rathkei); twice natural size. 

 Fig. 153. — The scorpion fly (Panorpa venosa); much enlarged. 

 Fig. 154. — A sphinx caterpillar, from Virginia creeper; natural size. 

 Fig. 155. — The unicorn larva from dogwood; enlarged. 



Pyramidula alternata, and Polygyra clausa, and rarely thyroides). Land 

 sowbugs are common (Fig. 152). Of the centipedes we note the long 

 ground form {Geophilus sp.) and sometimes the large millipede (Spiro- 



