ECOLOGICAL RELATIONS OF THE FLORA. 



39 



Scirpiis americanus. 

 Scirpus validus. 

 J uncus halticus littoralis. 

 Carex lupulina. 

 Salix nigra. 

 Mimidus ringens. 

 Lycopus americanus. 

 Cephalanthus occidentalis. 

 Eupatorium purpureum. 

 Eupatorium perfoliatum. 

 Quadrats* were laid out and a frequency count made with the follow- 

 ing results: 



Quadrats. 



Plant. 



Equisetum sylvaticum. . . . 



Carex filiformis 



Phragmites communis . . . . 



Scirpus validus 



Juncus halticus littoralis . 



Salix nigra 



Lycopus americanus 



Cephalanthus occidentalis . 

 Eupatorium purpureutn . . 

 Solidago juncea . 



Totals. 



1 

 40 



1 

 45 



1 

 25 



1 



ii: 



35 

 8 

 1 



35 



84 



4 

 35 



3 

 30 



1 

 20 

 10 



4 



15 

 4 

 1 



55 



Av. 



1 



32 



4 



2 



28 

 



10 

 2 



1 



] 



81 



Assuming that there were 80 to 100 plants to the sc^uare meter in this 

 association, if the individuals were evenly spaced each would have had 

 100 sq. cm. at its disposal. 



Where the xerophytic societies were establishing themselves by ad- 

 vance from the dunes surrounding the lagoon, the following plants 

 commonly found higher on the bank were the vanguard .in the in- 

 vasion. Many of these plants persisted in the helophytic society and 

 became prominent in the meadows — e. g., Hypericum kalmianum. 



♦The meter quadrats were made at typical localities by staking out a four meter rope in 

 the form of a square. The counts were made by pulling up the plants, and in cases of great 

 discrepancy in the size of the individuals, the number was obtained by lumping the small 

 plants and using the average leaf surface as a gauge. This lumping is but a rougii method 

 and can give only approximate results, but if a number of quadrats are taken and an average 

 of results made, the error will be largely effaced and the numbers obtained will indicate a fair 

 type. For example, although there is an excessive development of a species at one location 

 this is quite likely to be offset by a weaker showing at some other and the average will indicate 

 the general condition. In selecting quadrats the aim was to seek similar conditions where 

 the species were about of tlie same age. No attempt was made to have the quadrats include, 

 all the species listed for a place. The numbers obtained, therefore, indicate in each case what 

 may be expected at typical locations in such associations. 



