Vol. II 



December 4, 1921 



No. 20 



JOURNAL 



OP THE 



WASHINGTON ACADEMY 

 OF SCIENCES 



Robert B. Sosman 



OBOPBTSICAL LABOBATOKT 



BOARD OF EDITORS 

 S. F. Blakb 



BDBBAU OF PLANT OIDUSTST 



SiDNBT PaiGB 



O8OLOOICAL aORVST 



ASSOCIATE EDITORS 



H. V. Hari*an 



BOTANICAL SOCIBTV 



N. HOLLISTBR 



BtOLOOICAL aOCIBTT 



S. A. ROHWBR 



BNTOMOLOOICAL SOdBTt 



P. B. SiLSBSB 



PHXLOSOPRICAL SOCIBTY 



G. W. Stosb 



OBOLOOICAL SOCIBTY 



J. R. SWANTON 



ANTBBOPOLOOICAL SOCIBTY 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND SEPTEMBER, WHEN MONTHLY 



BY THB 



WASHINGTON ACADEMY OF SCIENCES 



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Entered at 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. 



