262 



OHIO BIOLOGICAL SURVEY 



Fig. 8. Blephariglottis iJaramoena Growing; in a Weedy Bottomland with Mixed Vegetation in 



which Agrimonia is Prominent. 



Even when themselves undisturbed, no other associations show so 

 quickly the effects of the changes in the land around them as the 

 bottom-lands. The periodical freshets are very et^icient carriers of seeds 

 from place to place. It is obvious that any change in the vegetation 

 at one place will change the character of the seeds carried down stream 

 into other unchanged societies. In the original condition of the coun- 

 try the seeds thus brought in by the freshets would represent largely 



