ZIMMERMAN: FORMATIVE INFLUENCES 

 TABLE 3. (Concluded) 



105 



Substances 



Cell elongation 



(epinasty) 



threshold cone. 



mg./g. 



Modification of 



tomato leaves 



threshold cone. 



mg./g. 



CH2COOH 











1 







/\C1 







2,4-DichIorophenoxyacetic acid 



0.015 



0.003 



CI 







CH3CHCOOH 











1 







/XCl 







a — (2,4-Dichlorophenoxy) propionic 0.5 

 \y acid 

 CI 



Inactive 



CH3CH0CHC00H 

 o 



/\C1 



a — (2,4-Dichlorophenoxy) -n-butyric 0.5 

 acid 



CI 



Inactive 



CH2COOH 



I 

 O 



I 

 /\C1 



CI 



CI 



2,4,5-Trichlorophenoxyacetic acid 0.06 



Inactive 



CH.3CHCOOH 



I 



O 

 I 

 /\C1 



CI 



CI 



a — ( 2,4,5-Tr ichlorophenoxy ) 

 propionic acid 



0.03 



Inactive 



CH3CH2CHCOOH 

 O 

 /\C1 



CI 



CI 



a — (2,4,5-Trichlorophenoxy) -n- 

 butyric acid 



0.1 



Inactive 



