Vol. VIII No. 6 



March 19, 1918 



JOURNAL 



OF THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOARD OF EDITORS 

 Adolph Knopf A. S. Hitchcock J. Fkanklin Meyeb 



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WASHINGTON ACADEMY OF SCIENCES 



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Entered as eeeond-class matter July 14, 1911, at the poet office at Baltimore, Maryland, uader the Act of 



July 10, 18M 



