ORGANIZATION OF THE UNITED STATES DEPARTMENT OF 
AGRICULTURE. 
SCCRELOTY Of AAGTICUILUTE® 222222) 5a. - eos lee Henry C. WALLACE. 
Missvsant Sccreltunyae. 9285.22... 2..... C. Ws PUGSLEY- 
DIRECHOE OF CICNDIILC WOT 2. = 215. .025--- - EK. D. Batu. 
Director of Regulatory Work. .....-..-.---- 
UCU CRU UNU fo S ORS 5 is CHARLES F. Marvin, Chief. 
Bureau of Agricultural Economics......... HENRY C. Taytor, Chief. 
urea of Ammoal Endustry. <0. 2-.2--- =. : JoHN R. Mower, Chief. 
Bureau of Plant Industry.....- tae ee Wiiuram A. Tayior, Chief. 
MOT EST DS CRINGE pre ae Re eS oe W. B. GREELEY, Chief. 
EremeOy CROMISTY ocean oe Se WALTER G. CAMPBELL, Acting Chief. 
ERGOT Oi ONG ere ere Sai se ds Mitton Wuitney, Chief. 
BRUTE OF FENIOMOLOGY): «222... 22222. o L. O. Howarp, Chief. 
Bureau of Biological Survey......-...-..... E. W. Netson, Chief. 
UTERUS OFF Whe ROCKS. 52 s2.. 2. eo THomas H. MacDona tp, Chief. 
Fized- Nitrogen Research Laboratory. .....-- F. G. Corrrett, Director. 
Division of Accounts and Disbursements. .... A. ZApPone, Chief. 
DDSI Of PUDICANONS soon ee ee Ls Joun L. Cosas, Jr., Chief. - 
MVOROTY Sac Seis Oe ri Gd ES Ss were CLARIBEL R. BaRNneET?, Librarian. 
iNiatcs RClALIONS SETDICE. 3 2aee en 2... ... A. C.-TRuet, Derector. 
Federal Horticultural Board...............- C. L. Maruart, Chairman. 
Insecticide and Fungicide Board.....-.-.---. J. K. Haywoop, Chairman. 
Packers and Stockyards Administration..... . ee Morri.1, Assistant to the Sec- 
Grain Future Trading Act Administration. .) retary. 
Waijicesof the SOuCcHtOr o.. 3S ess eee. R. W. Witturams, Solicitor. 
This bulletin is a contribution from the— 
PPCRIE OF Pig POMUSiY ce Neon cio. 3. os 2s 25 2-~--s---- WILLIAM A. TAYtor, Chief, 
Office of Sowl-Fertility Investigations. OswaLD SCHREINER, Biochemist in Charge. 
31 
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A 
