42 T. L. Lyon anp J. K. WILson 
this material would constitute only a small part of the total organic 
matter. | 
The presence of reducing substances in solutions in which plants hac 
grown was indicated by certain tests, but a number of other reagent 
failed to give reactions. Nitrates were nearly always reduced in thesi 
solutions in the presence of an antiseptic. Boiling the solution did no 
entirely prevent nitrate reduction, but it greatly decreased the rate a 
which reduction proceeded. | 
Peroxidases were always present in solutions in which plants had growr 
Boiling these solutions caused them to give no reaction for peroxidases 
Tests for other oxidizing substances were not sufficiently satisfactory t 
warrant the conclusion that they were present. 
