Vol. VII No. 15 



September 19, 1917 



JOUKNAL 



OF THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOAitD OF EDITORS 

 N. Ernest Dorset Adolph Knopf A. S. Hitchcock 



BOBBAU Or 8TANDABD9 GEOLOGICAL SURVEY BPfcKAC Or PLANT INDCSTB1 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND SEPTEMBER, WHEN MONTHLY 



WASHINGTON ACADEMY OF SCIENCES 



OFFICE OF PUBLICATION 



WILLIAMS & WILKINS COMPANY 



BALTIMORE, MO. 



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



July 16, 1891 



