ZIMMERMAN: FORMATIVE INFLUENCES 



103 



TABLE 3. Molecular Configuration and Comparative Activity of Phenoxy and 

 Substituted Phenoxy Compounds 



Substances 



Cell elongation Modification 



(epinasty) of tomato leaves 



threshold cone. threshold cone. 

 mg./g. mg./g. 



CHoCOOH 

 O 



Phenoxyacetic acid 



20 



Inactive 



CH3CHCOOH 

 O 



a — -(Phenoxy) propionic acid 



CH3CH2CHCOOH 

 O 



o — ( Phenoxy )-u-butyric acid 



CHoCOOH 



I 



6 



I 

 Aci 



o-Chlorophenoxyacetic acid 



1 



0.25 



CH3CHCOOH 

 O 



a — ( 2- Chlorophenoxy) propionic acid 1 



Inactive 



CH3CH2CHCOOH 



I 



o 



A" 



I J a — (2-Chlorophenoxy) -n-butyric acid 1 Inactive 



