ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 
AGRICULTURE. 
Secretary of Agriculture___________-_______- Henry C. WALLACE. 
PESO IEG SCUR CLOT ee a en C. W. PUGSLEY. 
Director of Scienttfie: Works... > Bare 
Purecior of Regulatory Werle... =. 
TET Ge es Ba) RET | aa ac” Sc CHARLES F. Marvin, Chief. 
Bureau of Agricultural Economics_________ _ Henry C. Taytor, Chief. 
Burcau. of Animal Industry: ~ = JOHN R. Mouter, Chief. 
ECA Of ENGI ANOUSET YS Wiitiam A. Tayntor, Chief. 
PEE ORE SCT UUCE oe oS = a a W. B. GREELEY, Chief. 
eC OT CCIUESEI one eee eS WALTER G. CAMPBELL, Acting Chief. 
SALE MILIO NOLS eaten te agg EE Mitton WHITNEY, Chief. 
Bureau of Hntomotogy=-— = L. O. Howarp, Chief. 
Bureau of Biological Survey. — = E. W. NELSON, Chief. 
PUTCO OF PIUUEC FROGWS =. ee eee Se THoMAS H. MaAcDonatp, Chief. 
Fized Nitrogen Research Laboratory______- F. G. CotTrett, Director. 
Division of Accounts and Disbursements____ A. ZAPPONE, Chief. 
Duwasion of Publications_2_ 23 eee JOHN L. Cogss, Jr., Chief. 
TRENT EU aE 8 Se eer CLARIBEL R, BARNETT, Librarian. 
States hetations Service___.__.- a A. C. TRvuE, Director. 
Pederal Hortieuliurat Board. > C. L. Margiatt, Chairman. 
Insecticide and Fungicide Board__________- J. K. Haywoop, Chairman. 
Packers and Stockyards Administration_____ CHESTER Morrit., Assistant to the 
Grain Future Trading Act see Secretary. 
Oyice Of the-Noherterss R. W. WrittaMs, Solicitor. 
This bulletin is a contribution from— 
PALE CEL: Of CRENUISUT AY. — — = ee W. G. CAMPBELL, Acting Chief. 
Miscellaneous Division__________-_-___- J. K. Haywoop, Chief. 
27 
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OF THIS PUBLICATION MAY BE PROCURED FROM 
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GOVERNMENT PRINTING OFFICE 
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AT 
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PURCHASER AGREES NOT TO RESELL OR DISTRIBUTE THIS 
COPY FOR PROFIT.—PUB. RES. 57, APPROVED MAY lI, 1922 
V 
