Vol. V No. 18 



November 4, 1915 



JOURNAL 



OP THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOARD OF EDITORS 



Fred. E. Wright William R. Maxon Edson S. Bastim 



oxopHTSiCAii laboratobt natiomal mubkum ssolooical acBvar 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND S^EPTEMBER, WHEN MONTHLY. 



BT THB ' 



WASHINGTON ACADEMY OF SCIENCES 



OFFICE OF PUBLICATION 



THE WAVERLV PKESS 



BALTIMORE, MD. 



