Bui. 108. U. S. Dept. of Agriculture. 
Plate VI. 
Effect of Substance Extracted from Poor and Good Miami Stony Loam (No. 
1 T, Table IX, and No. 41, Table X) on Wheat Plants. 
(1) Distilled water; (2) distilled water plus material from poor soil containing aldehyde; 
(3) distilled water plus material from good soil showing no aldehyde reactions. 
