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 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, 



Grain Future- Trading Act Administration . . . .[ Assistant to the Secretary. 



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



This bulletin is a contribution from 



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



Division of Biological Investigations E. A. Goldman, Assistant in Charge 



36 



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