378 
Journal of Agricultural Research 
Vol. II, No. s 
elude that “oxidase” and “oxygenase” are practically lacking in em¬ 
bryonic organs and that their concentration in these plants rises during 
growth and diminishes again when growth has stopped. They draw 
their conclusions entirely from the quantity of C 0 3 liberated by the 
Fig. i.—R ate of development of the aerial portion of potato plants and mean rate of development of all the 
single shoots in one hill. 
plant organs under different conditions. It seemed of great interest, 
therefore, to find out what relation the concentrations of the oxidases 
present in the pressed-out sap of a plant bear to the state of development 
of the same plant. 
