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Fresh-water Biology 



II. Animals — with notes on size, relative abundance, feeding habits, stages or 

 ages found, habitats and special adaptations, and activities. 



A. Vertebrates — fishes— others. 



B. Invertebrates. 



(a) Free swimming. 



(b) On the surface. 



Walking on the surface. 

 Lying in the surface film. 

 Suspended from the surface film. 



(c) On the vegetation (and on other supports). 



Sessile forms. 

 Free ranging forms. 

 Tube dwellers. 



(d) On the bottom. 



Sprawlers. 

 Burrowers that dig. 

 Burrowers that squeeze through. 

 Tube dwellers. 



3. Make this diagram over to suit the pond studied. Write in the names of the 

 most t>-pical forms of each stratum. 



