April, 1908.] The Vegetation of Cedar Point. 335 



The fades of this formation exhibit more or less zonation. 

 Castalia ttiberosa generally forms a Consocies in the deeper part 

 of the habitat of the formation while the shallower part of the 

 formation often has alternating Nymphaea advena Consocies and 

 Nelumho lutea Consocies. Over a large part of the habitat, 

 however, the facies are mingled to such an extent that the con- 

 socies structure is not evident. 



The Pontederia cordata Society is not ordinarily of large ex- 

 tent but the plant usually appears in dense ecological famiHes 

 and communities. This Society is usually associated with the 

 Nymphaea advena and the Nelumho lutea Consocies in the shal- 

 lower water of the habitat. 



Fig. 19. The Nelumbo lutea Consocies mingled in the left background 

 with the Pontederia cordata Society. The general background being the 

 Phragmites phragmites Consocies of the Marsh Formation. In the third 

 cove south of Biemiller's Cove. 



The Utriailaria vulgaris Society determines a quite conspicu- 

 ous aspect in midsummer in some of the little bays and inlets 

 opening off from the larger body of the cove into the marsh, — 

 usually in water of not more than six or eight inches in depth 

 with a deep semi-liquid muck bottom. 



The Zizania aquatica Society determines a conspicuous au- 

 tumnal aspect almost throughout the whole formation except, 

 perhaps, in the very deepest part. During midsummer this 



