ORGANIZATION OF THE UNITED STATES DEPARTMENT OF AGRI- 
CULTURE. 
Secretary of Agriculture Henry C. Wallace. 
Assistant Secretary C. W. Pugsley. 
Director of Scientific WorJ: E. D. Ball. 
Director of Regulatory WorJ: 
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 Melton 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. 
i Nitrogen Research Laboratory F. G. Cottrell, Director. 
on 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 ) Secretary. 
Office of the Solicitor R. W. Williams, Solicitor. 
This bulletin is a contribution from 
Bureau of Plant Industry William A. Taylor, Chief. 
Fruit Disease Investigations Merton B. Waite, Pathologist in Charge. 
39 
additional copies 
OF THIS PUBLICATION MAY BE PROCURED FROM 
THE SUPERINTENDENT OF DOCUMENTS 
GOVERNMENT PRETTNG OFFICE 
"WASHINGTON, D. C. 
AT 
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