84 Proceedings of the Ohio State .Icculeniy of Science. 



Secondary species : 



Cyperus strigosus Typha latifolia 



Ilysanthes gratioloides Alisma plantago 



. Hypericum pennsylvanicum Amaranthus hybridus 



Polygonum acre Arctium minus 



Agrostis perennans Acer rubrum seedling 



Gratiola virginiana Ulmus americana seedling 



Erechtites hieracifolia Hibiscus moscheutos seedlings 



Echinochloa walteri Scirpus lacustris 



Eupatorium purpureum Cladophora sp. 

 Roripa palustris 

 americana 



This society is 40 feet wide with the entire surface exposed 

 at the present low water level. Hence the extremely heterogenous 

 collection of plants among the secondary species. Dead Typha 

 latifolia stalks are so abundant in the wstern portion of the 

 zone as to warrant considering it a dominant plant ; but the 

 Typha is not at all abundant in the eastern portion of the zone. 

 Articum minus and Alisma plantago growing close together illus- 

 trate strikingly the submerged and emersed stages of the society 

 and the rapidity with which a new habitat is adopted by plants. 

 That the ground has been recently exposed is evidenced by the 

 fresh masses of Cladophora. 



10. Scirpus lacustris society. This is a fringing zone 40 

 feet wide and extending only about half way across the belt, the 

 surface is partly emersed. There is a 20-foot wide sandy beach 

 scantily clothed with the Scirpus. 



Secondary species : 



Potamogeton natans 



pectinatus 



lonchites 

 Nelumbo lutea 



The pond association along the north shore is represented 

 only by a Nelumbo lutea society. A small bed of Nelumbo 

 lutea borders the Scirpus lacustris society to the north-north- 

 east. The leaves are but few and widely scattered. 



