Vol. VIII Ko. 12 



June 19, 1918 



JOUENAL 



OF THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOARD OF EDITORS 

 Adolph Knopf A.S.Hitchcock J. Franklin Metbb 



QBOLOOICAL BUBVKT bURBAi; OP PLANT IMDUBTBT BUBSAO OF STANDABD» 



PUBLISHED 8EM-M0NTHLY 

 EXCEPT IN JULY, AUGUST. AND SEPTEMBER, WHEN MONTHLY 



BT TBB 



WASHINGTON ACADEMY OF SCIENCES 



OFFICE OF PXTBUCATION 

 WILLIAMS & WILKINS COMPANY 

 < BALTIMOBB, MD. 



Eotered aa second-class matter July 14, 1911, at the post o£Bce at Baltimore, Maryland, under the Act of 



July 16, 1894 



