Voi,. lo D^c^MB^R 4, 1920 No. 20 



JOURNAL 



OF THB I 



WASHINGTON ACADEMY 

 OF SCIENCES 



BOARD OF EDITORS 



J. PRAMKI,IM MSTBE ROBBKT B. S08MAV S. P. BtAQ 



BOKSAO OV BTAMDAKDa 080PHTUCAI, LABOBATOKV BUKBAD 0» tUAlUt nOUSTST 



ASSOCIATE EDITORS 



H. V. Haklam S. a. RohwHr 



BOTAMICAt BOCniTT BMTOltOUKIieAI. BOCISTT 



N. HomSTBR p. B. SIL8BBS 



BIOLOGICAL BociBTT mLoeopncAi Moetmn 



Sn>NBY PaIGB J. R. SWANtOM 



OBOLOoicAL soeiBrr AaxnopoLooiCAii tocnrT 



PUBLISHED Stm-UONtHLT ^ 



SZCBPT m JXTLY, AUGUST, AND SSPTHMBBR, WBBN UOMTHLT i 



BT THS I 



WASHINGTON ACADEMY OP SCIENCES J 



OPVtCS 09 PUBUCATION 



an CHUKCH sntBST 



SASTON, PA. 



Bntered u Sacond Clan Matter, January 25, 1919, at the port-affiet at Baataa, Pa., aadar the 

 Act of Aagiut 24, 1912. Acceptance for nailing at ipecial rate of poatage provided for is 

 SecttoB 1103 Act of October 3. 1917. Aathoriaed on Jalj 3. 191t 



