34 T. L. Lyon anp J. K. WiItson 
for the data shown in table 4, but the growth of the maize plants in thel 
sterile flasks also was less. The quantity of inorganic matter and of 
organic matter appears to decrease and increase at the same periods if) 
credence is to be given to the data from the last two flasks opened. The 
TABLE 4. Torat Orcanic Matter AND NITROGEN PRESENT IN SOLUTIONS AT SUCCESSIVE 
Sraces IN THE GRowTH OF Maize 
iKandlofaplantivs eto e eee eee Maize Maize Maize Maize 
Serialinoie ys een eae eee ee ane 1 2 3 Ls 
Date of setting plant in flask.......... June 28 | June 28 June 28 June 28} 
Date of removing plant from flask. .... Aug. 3 Aug. 16 Aug. 30 Sept. 2( 
Growing period (days)..... meet ek see 36 49 63 84 | 
Dry matter in plant (milligrams).......| 10,200.0 | 24,100.0 32 ,200.0 65 ,000.( 
Volume of solution at harvest (cubic 
Centimeters eee eee cee 6,200.0 | 6,950.0 2,850.0 2,790.4 
Condition*of solutions ..9m--< so ee Sterile Sterile | Contaminated Mold) 
Nitrogen as nitrates in solution (milli- j 
STAINS) ite percent ean as eee fe ees 32.4 Trace 0.0 0.6 
Inorganic matter in solution (milligrams)| 1,333.0 | 1,056.4 310.6 460 <) 
Organic matter in solution (milligrams) 291.4 284.9 76.9 2518 
data for inorganic matter were probably not influenced by the infectio1) 
of flask no. 3, and this shows a gradual decrease in amount up to th 
sixty-third day of growth and then an increase at maturity, indicating ¢ 
liberation of salts from the plant. Such liberation must, of course, hay) 
been by way of the roots. Admitting, then, that inorganic matter may be 
removed by the action of rainfall on the leaves, of which the investigation! 
of Le Clerc and Breazeale leave little doubt, there appear to be at leag| 
two means by which this material may be liberated by the plant. 
REDUCING AND OXIDIZING SUBSTANCES LIBERATED BY PLANT ROOT q 
While many investigations have been made of the oxidizing and reducin), 
enzymes in plants, very few have been undertaken for the purpose ( 
ascertaining whether any of these bodies appear in the substratum j 
which the roots of plants are immersed. It was thought that the steri) 
different kinds and of different stages of growth were produced, woul}, 
permit of a series of tests for these substances under conditions the} 
would exclude contamination from the seed or from outside source) 
