Vol. V No, 20 



December 4, 1915 



JOURNAL 



OF THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOARD OF EDITORS 



I 



Fred. E. Wright William R. Maxon Edson S. B.vstin 



SEoPBTsiCAi. labobatoby Rational uubbum qbolooical BOBVKr 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND SEPTEMBER, WHEN MONTHLY. 



BT THB 



WASHINGTON ACADEMY OF SCIENCES 



office of publication 



the waverly press 



baltimore, md. 



Entered as eecond-class matter July 14, 1911, at the post office at Baltimore, Marylaad, under the Act oi 



July 16, 1894 



