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VOLUME 8 JULY, 1922 NUMBER 7 1 1 
I ;| 
PROCEEDINGS | ] 
OF THB I 1 I 
National Academy | j 
OF Sciences | j 
OF THE I I 
UNITED STATES OF AMERICA I t 
^ EXECUTIVE COMMITTEE 
Edwin Bidwbll Wilson, Managing Editor 
Raymond Pbarl Vsrnon Kbllogg 
PUBUSHBD MONTHLY | 
Publication Office: Eschenbach Printing Company, Easton, Pa. 1 
Editorial Office: Harvard School of Public Plealth, Boston 17 J 
Home Office of the Academy: Washington, D. C. | 
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jBoterad as second-class matter June 21, 1920, at the postoffice at Easton, Pennsylvania, under the act off August 24, 1912. 
jAcceptance for mailinar at spcdai rate of postage provided for in section 1103, Act of October 3, 1917. Authorized June 18, 1920. 
Price per annum, $5.00 
