394 Proceedings Portland Society Natural History 



muddy shores have a much larger variety. Along rocky 

 shores, especially in the larger lakes, such as Alamoosook 

 in Orland (Figure 31) and Megunticook in Camden, the 

 action of waves and ice tends to keep out any plants save 

 perhaps the submersed and floating aquatics. The follow- 

 ing list of species are of most frequent occurrence : 



Equisetum fluviatile Eriocaulon septangulare 



Typha latifolia J uncus militaris 



Sparganium americanum Nuphar variegatum 

 Potamogeton Oakesianus Nymphaea odorata 

 Potamogeton nutans Potentilla palustris 



Sagittaria latifolia var. villosa 



Dulichium arundinaceum Slum cicutaef olium 

 Eleocharis palustris Lysimacliia terrestris 



Scirpus validus Xymphoides lacunosum 



Cladium mariscoides Utricularia vulgaris 



Car ex filiformis var. americana 



Acorus Calamus Lobelia Dortmanna 



Pontederia cordata 



The submersed and floating aquatics cited in this list are 

 usually to be found in all ponds, but the species of the third 

 stage vary in different localities. Perhaps the most fre- 

 quent plant is Carex filiformis, which covers extensive areas 

 and often invades the zone of water lilies (Figures 32 and 

 33). With it are usually associated Potentilla palustris 

 var. villosa and Equisetum fluviatile. Again the pickerel 

 weed (Pontederia cordata) or the bulrush (Scirpus validus) 

 may predominate. In a few instances Cladium mariscoides 

 and Juncus militaris are the most important species. The 

 cat-tail (Typha latifolia) is occasional, but this plant is 

 more typical of small periodic or brackish ponds. On the 

 western side of the Bay the buck bean (Menyanthes tri- 

 foliata) is extremely abundant in the shallow water along 

 muddy pond shores, where it forms extensive mats, some- 

 times to the exclusion of all other species. On the eastern 

 side of the Bay, however, this plant is practically absent. 



