1 
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VOLUME 2 DECEMBER, 1916 NUMBER 12 
PROCEEDINGS I 
I 
OF THE I 
National Academy | 
OF Sciences | 
1 
OF THE i 
UNITED STATES OF AMERICA 
/ 
EDITORIAL BOARD 
Arthur A. Noyes, Chairman Edwin B. Wilson, Managing Editor | 
Arthur L. Day, Home Secretary George E. Hale, Foreign Secretary 1 
J. J, Abel J. M. Coulter W. H. Holmes | 
W. B. Cannon C. B. Davenport J. P. Iddings 1 
J. McK. Cattell Simon Flexner R. A. Millikan 
J, M. Clarke E. B. Frost E. H. Moore 
E. G. CoNKLiN R. G. Harrison Alexander Smith 
Publication Office: Williams & Wilkins Company, Baltimore 
;Editona> Office: Massachusetts Institute of Technology, Cambridge 
Home Office of the Academy: Washington, D. C. 
Entered aa second-class i^atter at the Post Office at Baltimore, Md., vuder the Act of August 24, 3912 
