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 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. 0. 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 Edwin C. Powell, Acting Chief. 
Library Clarlbel 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 "I 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 Chemistry Walter G. Campbell, Acting Chief. 
Miscellaneous Division J. K. Haywood, in Charge. 
Bureau of Entomology L. 0. Howard, Chief. 
Fruit Insect Investigation A. L. Quaintance, Entomologist in 
Charge. 
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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.— PUB. RES. 57, APPROVED MAY 11, 1922 
