April, 1908.] 



The Vegetation of Cedar Point. 



333 



Facies: Potamogctoji perfoliatus , 

 Potantogeton lonchites, 

 Potamogeton pusillus. 

 Principal Species: 



Vallisneria spiralis , 

 MyriophyUum spicatum . 

 Secondary Species: 

 Potamogeton natans, 

 Potamogeton amplifolius , 

 Naias flexilis, 

 Castalia tuber osa, 

 Scirpus validus, 

 Ceratophyllum demersum. 



Potamogeton foliosus, 

 Potamogeton zosteriaef alius, 

 Philotria canadensis, 

 Nymphaea advena, 

 Nelumho lutea, 



Fig. 17. A Pontederia cordata Society along the submerged bar at the 

 south end of Biemiller's Cove. The Typha latifolia Consocies of the 

 Phragmites-Typha Marsh Formation in the background. 



The mass of vegetation comprising this formation is altogether 

 quite large and the water is often so thoroughly filled up with it 

 that, looked at from above, the space appears completely taken 

 up by the vegetation in the middle and lower depths. The con- 

 ditions are very good for the accumulation of considerable de- 

 posits of vegetable debris and for straining out suspended sedi- 

 ments in the water, or for obstructing to some extent floating 

 debris, so as to finally lead to its deposition on the bottom. Un- 

 der conditions of stable equilibrium, as to the relative position 

 of water level and the land, this formation could be expected 



