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Aquatic Societies 



Pond societies — The kind of associations we now come 

 to discuss are typically represented in ponds, but they 

 occur also in any bodies of standing fresh water, that 

 are not too deep for growth of bottom herbage, nor too 

 exposed to wind and wave for the growth of emergent 



Fig. 19.S. Where marsh and pond meet. The head of "the cove" at the Cor- 

 nell Biological Field Station. Beds of spatterdock backed by acres of cat- 

 tail flag. Neguena valley in the distance. 



aquatics along shore. The same forms will be found 

 in ponds, lagoons, bayous, sheltered bays and basin- 

 like expansions of streams. The bordering aquatics 

 will tend to be arranged in zones, as discussed in the 

 preceding pages, according to the closeness of their 

 crowding. 



1. The shoreward zone of emergent aquatics will 

 include, in our latitude, species of cat-tail (Typha), of 



