Voi,. 9 February 19, 1919 No. 4 



JOURNAL 



OF THE 



WASHINGTON ACADEMY 

 OF SCIENCES 



BOARD OF EDITORS 



A. S. HITCHCOCK J. Franklin Meyer R. B. Sosman 



BUREAU OP PLANT INDUSTRY BUREAU OP STANDARDS GEOPHYSICAL LABORATORY 



ASSOCIATE EDITORS 



N. HOLUSTER S. A. ROHWER 



BIOLOGICAL SOCIETY ENTOMOLOGICAL SOCIETY 



J. B. Norton J. R. Swanton 



BOTANICAL SOCIETY ANTHROPOLOGICAL SOCIETY 



Sidney Paige - F. B. Silsbee 



GEOLOGICAL SOCIETY PHILOSOPHICAL SOCIETY 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND SEPTEMBER, WHEN MONTHLY 



BY THE 



WASHINGTON ACADEMY OF SCIENCES 



OFFICE OF PUBLICATION 



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E ASTON, PA. 



Entered as Second Class Matter, January 25, 1919, at the post-office at Easton, Pa., under the 

 Act of August 24, 1912. Acceptance for mailing at special rate of postage provided for in 

 Section 1103, Act of October 3. 1917. Authorized on July-3. 1918 



