﻿Vol. 
  12 
  March 
  19, 
  1922 
  No. 
  6 
  

  

  JOURNAL 
  

  

  OF 
  THB 
  

  

  WASHINGTON 
  ACADEMY 
  

   OF 
  SCIENCES 
  

  

  BOARD 
  OF 
  EDITORS 
  

   S. 
  P. 
  Blakb 
  Sidnbt 
  Paigb 
  E. 
  D. 
  Wiuiahsok 
  

  

  aOBBAD 
  0» 
  PLAMT 
  DtDUBntT 
  OSOUXIICAI, 
  SCBVav 
  OSOPHTSaCAI. 
  LABOSATOST 
  

  

  ASSOCIATE 
  EDITORS 
  

  

  H. 
  V. 
  Hau^m 
  S. 
  A. 
  RoHWBK 
  

  

  BOTAincAi 
  •oGisrr 
  siiTOMOLoaicAL 
  •oenri 
  

  

  N. 
  HOLUSTBR 
  G. 
  W. 
  Stosb 
  

  

  BIOLOGICAL 
  aoCIBTT 
  OBOLOOICAL 
  ■OCnTT 
  

  

  W. 
  P. 
  MBGG8RS 
  J. 
  R. 
  SWAMTON 
  

  

  PRILOSOPBJCAL 
  •OCIBTT 
  AMTHKOPOLOOICAL 
  aocmrr 
  

  

  PDBUSBBD 
  SSm-lfONTHLT 
  

   BXCBPT 
  IN 
  JULY. 
  AUGUST, 
  AND 
  SBPTSMBBR, 
  WH8N 
  MONTHLY 
  

  

  BT 
  TBR 
  

  

  WASHINGTON 
  ACADEMY 
  QF 
  SCIENCES 
  

  

  OPPICB 
  OP 
  PUBLICATION 
  

  

  211 
  CHURCH 
  8TRBET 
  

  

  EASTON, 
  PA. 
  

  

  Entered 
  as 
  Second 
  Class 
  Matter, 
  January 
  25, 
  1919, 
  at 
  the 
  post-office 
  at 
  Easton, 
  Pa., 
  under 
  the 
  

   Act 
  of 
  August 
  24, 
  1912. 
  Acceptance 
  for 
  mailtng 
  at 
  special 
  rate 
  of 
  postage 
  provided 
  for 
  

   in 
  Section 
  1103, 
  Act 
  of 
  October 
  .3, 
  1917. 
  Authorized 
  on 
  July 
  3, 
  1918. 
  

  

  