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Vot. 13 March 4, 1923 No. 5 
JOURNAL | 
WASHINGTON ACADEMY 
OF SCIENCES , 
BOARD OF EDITORS 
SIpNEY PAIGE E. D. WriiiaMson E. P. Kruurp 
GEOLOGICAL SURVEY GEOPHYSICAL LABORATORY NATIONAL MUSEUM 
ASSOCIATE EDITORS 
H. V. HarRuan 
BOTANICAL SOCIETY 
S. A. RoHwER 
ENTOMOLOGICAL SOCIETY 
N. Houuister G. W. Stross 
BIOLOGICAL SOCIETY 
W. F. Mecarrs 
PHILOSOPHICAL SOCIETY 
GEOLOGICAL SOCIETY 
J. R. Swanton 
ANTHROPOLOGICAL SOCIETY 
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Entered as Second Class Matter, January 11, 1923, at the post-office at Baltimore, Md., under the 
Act of August 24,1912. Acceptance for mailing at special rate of postage provided for 
é in Section 1103, Act of October 3, 1917. Authorized on July 3, 1018, 
