ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 

 AGRICULTURE. 



Secretary of Agriculture Heney C. Wallace. 



Assistant Secretary C. W. Pugsley. 



Director of Scientific Work E. D. Ball, 



Director of Regulatory Work 



Weather Bureau Charles F. Marvin, Chief. 



Bureau of Agricultural Economics Henry C. Taylor, Chief. 



Bureau of Animal Industry John R. Mohler, Chief. 



Bureau of Plant Industry William A. Taylor, Chief. 



Forest Service W. B. Greeley, Chief. 



Bureau of Chemistry Walter G. Campbell, Acting Chief. 



Bureau of Soils Milton Whitney, Cliief. 



Bureau of Entomology L. O. Howard, Chief. 



Bureau of Biological Survey E. W. Nelson, Chief. 



Bureau of Public Roads Thomas H. MacDonald, Chief. - 



Fixed-Nitrogen Research Lal}oratory F. G. Cottrell, Director. 



Division of Accounts and Disbursements A. Zappone, Chief. 



Division of Publications John L. Cobbs, Jr., Chief. 



Library Claribel R. Baenett, Librarian. 



States Relations Service A. C. True, Director. 



Federal Horticultural Board C. L. Marlatt, Chairman. 



Insecticide and Fungicide Board J. K. Haywood, Chairman. 



Packers and Stockyards Administration "IChester Morrill, Assistant to the 



Grain Future-Trading Act Administration J Secretary. 



Office of the Solicitor R. W. Williams, Solicitor. 



This bulletin is a contribution from the 



Bureau of Plant Industry William A. Taylor, Chief. 



Office of Crop Physiology and Breeding 



Investigations Walter T. Swingle, Physiologist 



in Charge. 

 36 



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