40 ECOLOGICAL RELATIONS OF THE FLORA. 



Transition Species: 



Spartina cynosuroides. 

 Carex muhlenhergii. 

 Rubus hispidus. 

 Desmodium paniculatum. 

 Apios tuberosa. 

 Hypericum perforatum. 

 Hypericum kalmianum. 

 Teucrium canadense. 

 Solidago graminifolia. 

 Solidago juncea. 



Reed Swamp Formation — Phragmites Association: The type studied 

 was an expanse of grassy meadow probably a mile square situated 

 at the base of the Point. It was principally covered by tall grasses 

 and was studded with clumps of bushes, and the zones* were the same 

 as in the younger stage of the formation, although the dominant species 

 had changed with the conditions. This meadow evidently represented 

 an old bay, cut off from Wild Fowl Bay by a sand spit and subsequently 

 filled by inwash and the accumulation of vegetal debris, the history 

 being revealed quite as plainly by the vegetation as by the physio- 

 graphy. 



The Phragmites association follows the Juncus, Scirpus, and 

 Carex associations. At Long Lake we saw the encroachment 

 of the swamp plants in the open water. With the filling of such a lake 

 the Scirpus association disappeared, the Carex stools gave way to the 

 rhizome propagation of Phragmites and the swale resulted. The 

 process was an elimination of the more h^^droph^^tic societies and kept 

 pace with the disappearance of the open water. At the time studied 

 the general elevation was just about at lake level, but the formation of 

 "woody islands" had begun, as was shown by the clumps of trees 

 and shrubs that differentiated the grassy plain. (Plate VI a ) 



The plants did not grow close together and xerophytic structures 

 were common. Holes sunk at various parts of this swamp showed 

 black amorphous peat to the depth of more than two feet. Roots 

 and stems were also found to this depth, showing that the substratum 

 was built partly by living plants and was not merely a silt deposit. 



^Editor's Note. — This paper having been written before the rulinps on nomenclature bv the 

 Brussel's congress were made the word zone is used throughout in the sense of girdle or belt as 

 now used in Ecologj'. 



