a 
LIBERATION OF ORGANIC MATTER BY Roots oF GROWING PLANTS 19 
Fig. 3. MAIZE PLANTS GROWN IN Fic. 4. PEA PLANT GROWN IN 
STERILE SOLUTION FoR 189 Days STERILE SOLUTION FoR 139 
(Table 1, serial no, 1303) WEES, 
(Table 1, serial no. 1280) 
