ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 
AGRICULTURE. 
Secretary of Agriculture Henby 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, Chief. 
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 laboratory F. G. Cottrell, Director. 
Division of Accounts and Disbursements A. Zappone. Chief. 
Division of Publications John L. Cobbs, Jr., Chief. 
Library Claribel R. Barnett, 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 ___! Chester 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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