p. W. ZIMMERMAN 



177 



The principal modifications induced by active substances are changes 

 in flowering habit, size, shape, pattern, and venation of organs. The blade 

 of the leaf is usually reduced in area, and the veins converge toward the 

 midrib. Clearing of the modified veins, mottling, and other symptoms 

 often cause modifications which may be confused with virus diseases. 

 Leaves often fail to separate from each other, forming large modified 

 organs or cups. Flower buds become tubular where sepals fail to separate, 

 and ovaries frequently develop into seedless fruit. Flowering habit and 

 correlation of organs are modified especially by derivatives of benzoic 



TABLE 2 



Molecular configuration and comparative activity of substituted phenoxyali- 

 phatic acids involving the tomato plant as test object 



