420 CRAFTS 



likely from the processes affected that many terminal systems are involved. 



Considering tissue differentiation, certain herbicides are able to alter the 

 processes involved to the extent of greatly modifying structure. Typical 

 chemicals exerting such formative effects are the phenoxy compounds, tri- 

 chloro-benzoic acid, maleic hydrazide, T.C.A., Dalapon, amino triazole, and 

 the chloroacetamides. Typical plants are cotton, Tokay grapes, black-eyed 

 peas, certain cereals, and a wide array of weeds. 



Finally, with the increasing interest in experimental morphology, it seems 

 possible that these and other yet undiscovered chemicals may be used com- 

 paratively to analyze differentiation processes and eventually to characterize 

 and explain them. Such chemical tools have the advantage over surgical pro- 

 cedures of being absorbed, translocated, and eventually metabolized by intact 

 plants. 



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Crafts, A. S. 1945. A new herbicide, 2,4-dinitro 6 secondar>' butyl phenol. Science 

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