Abstract
1n the autumn of 1933 Miss Agatba Griffin (3) studied the influence of interrupted translocation on loss of chlorophyll in leaves before autumn coloration. During the course of the observation, it was noted that a gall on the vein of leaves of Quercus alba produced strikingly similar results as cutting of a vein, i. e., in both cases the area above the cut or gall growth lost its chlorophyl1 first and turned strikingly red several weeks before the portion below the cut or gall discolored. It was at that time assumed and substantiated by superficial examination that the gall induced some sort of modification in the conducting tissue of the leaf, thus affecting translocation. To investigate the nature of this modification in the vascular tissues is the specific aim of the present study.
