ORGANIZATION OF THE 
UNITED STATES DEPARTMENT OF AGRICULTURE. 
Secretary of Agriculture Henry 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 Economic* 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 Surrey 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 Edwin C. Towell, Acting 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 1 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 
Bureau of Biological Surrey E. W. Nelson. Biologist and Chief. 
Division of Economic Investigations- A. K. Fisher, in Charge. 
60 
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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.— PUB. RES. 57, APPROVED MAY 11, 1922 
