

Vol. VI No. 6 



March 19, 1916 



JOURNAL 



OF THE 



WASHINGTON ACADEMY 



OF SCIENCES 



BOARD OF EDITORS 

 William R. Maxon Edson S. Basttn N. Ernest Dorse* 



NATIONAL MUSEUM GEOLOGICAL SURVEY BUREAU OP STANDARDS 



PUBLISHED SEMI-MONTHLY 

 EXCEPT IN JULY, AUGUST, AND SEPTEMBER, WHEN MONTHLY 



BY THE 



WASHINGTON ACADEMY OF SCIENCES 



OFFICE OF PUBLICATION 



WILLIAMS & WILKINS CO. 



BALTIMORE, MD. 



Entered aa second-olass matter July 14, 1911, at the post office at Baltimore, Maryland, under the Act oi 



July 16. 1S94 



