Vol. io October 19, 1920 No. 17 



JOURNAL 



OF THE 



WASHINGTON ACADEMY 

 OF SCIENCES 



BOARD OF EDITORS 



J. PRAMKLIM MBYBK ROBBKT B. SoSUAM S. P. BLAXS 



BCBSAO oy B7AMDAXIM OSOPBTnCAL LABOKATOKT BCSBAU OV PLANT DIDCBTBT 



ASSOCIATE EDITORS 



H. V. Haklam S. a. Rohwrk 



BOTAMICAI, lOCntTT BIITOMOI,OOieAI. BOCtBTT 



N. H0U.ISTSR p. B. SII.8B9B 



BioLooicAi, BociSTT PKiMMoraieAi, aoenTT 



SlDNKY PAIGS J. R. SWANTON 



aBOI.OOtCAI. BOCIBTV ANTHBOPObOOICAI. BOCISTV 



PT7BUSHBD SSm-MONTHLT 

 SStCBPT m JULY. AUGUST, AND SBPTBUBBR, WHBN MOMTHLT 



BT THB 



WASHINGTON ACADEMY OP SCIENCES 



OPTICS or PUBUCATION 



211 CHUKCH STKBBT 



BASTON, PA. 



Bntaced aa S«eoad CUaa Matter, Jmnnary 25, 1919. Bt tht poat-^fBc* Bt BBitoa. Pb.. ■adav tht 

 Act of Aagiiat 24, 1912. Acceptance f«r mailiag at Bpedal rate Bf poBtag* prBvlded far ia 

 Secttoa 1103 Act of OetBbcr 3, 1917. Aathatteed bb Jaly 3. 1911 



