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I VOLUME 8 SEPTEMBER, 1922 NUMBER 9 
I PROCEEDINGS 
-I OF the: 
I National Academy 
I 
1 OF Sciences 
1 
I OF THE 
I UNITED STATES OF AMERICA 
I 
M 
m 
m 
EXECUTIVE COMMITTEE 
Edwin Bidwei.Iv Wii^son, Managing Editor 
Raymond Peari. Vernon Kei.i.ogg 
1 PUBLISHED MONTHLY M 
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g Publication Office : Eschenbacli Printing Company, Easton, Pa. g 
I Editorial Office: Harvard School of Public Health, Boston 17 | 
1 ^ Home Office of the Academy: Washington, D. C. 1 
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Entered as second-class matter June 21, 1920, at the postoflSce at Easton, Pennsylvania, under the act oi August 24, 1912. 
Acceptance for mailing at special rate of postage provided for in section 1103, Act of October 3, 1917. Au^orized June 18, 1920. 
Price per annum, $5.00 
