334 



BOTANICAL GAZETTE 



[APRIL 



Fig. 2.— Roots from soil fertilized with 5 tons of manure: left to right carbon 

 dioxide treatments of soil were o, 8, and 24 hours per day. 



Fig. 3.— Roots from soil fertilized with single application of complete fertilizer 

 left to right carbon dioxide treatments of soil were o, 8, and 24 hours per day. 



