254 



ILLINOIS ACADEMY OF SCIENCE 



realize that the actual amount of heat received during a 

 season by bottomland plants is very much less than that 

 received by upland plants and may be an extremely im- 

 portant environmental factor. 



SO' 



IS' 



70' 



hS' 



\>0' 



i5' 



SO' 







FlS-U.SoU Xeniperixutes 4t 12 iyiches 



