i5o 



POND COMMUNITIES 



painted turtle {Chrysemys marginata) is abundant, basking on the fallen 

 trees. The geographic turtle and the snapping turtle are found also 

 in the younger phases. Garter-snakes pick up their food along the 

 ponds (Fig. 114), while muskrats, occasional minks, and various aquatic 

 birds (108) feed in the ponds. 



Senescent Pond Inhabitants 



Fig. 109. — A leech with young attached to the ventral side (Placobdella para- 

 sitica) ; natural size. 



Fig. 1 10. — The larva of a netted-winged insect (Chauliodcs rastricomis). 



Fig. hi. — Pupa of the same (slightly enlarged). 



Fig. 112. — A snail {Planorbis trivolvis); natural size. 



Fig. 113. — Common amphipod (Eucrangonyx gracilis) ; twice natural size. 



Fig. 114. — Pond 58 in a dry season, showing dead fish (mud minnows) both 

 on bottom and out of water and in the water. A garter-snake (Thamnophis sp.) 

 feeding on the fish. 



Consocies of logs. — This is the chief place to find the sponge and the 

 polyzoa. Their numbers vary from year to year but they are usually 



