334 



TABLE I continued. 

 ORGANISMS PER CUBIC METER IN PLANKTON OF ILLINOIS RIVER IN 1898. 



(An asterisk at head of column indicates that all entries in it are based on 

 filter-paper collections.) 



Average . 



1,674 



67 



50 



.57 



388 



86,674 



3,598 ; 



1,768 



