﻿Rusk: 
  Protoplasmic 
  streaming 
  

  

  429 
  

  

  

  

  TABLE 
  I 
  

  

  

  

  ' 
  

  

  V 
  

   4 
  

  

  Elodea 
  

  

  » 
  

  

  

  w 
  

  

  Fraction 
  N 
  

  

  No. 
  of 
  cells 
  

  

  Average 
  dis- 
  

  

  Rate 
  per 
  100 
  mi-. 
  

  

  % 
  Acceleration 
  

  

  % 
  Retardation 
  

  

  ZnS04 
  

  

  tested 
  

  

  tance 
  in 
  microns 
  crons 
  in 
  seconds 
  

  

  of 
  normal 
  

  

  of 
  normal 
  

  

  1 
  

  

  o.oooo 
  

  

  137 
  

  

  105.30 
  

  

  1 
  

  

  16.83 
  

  

  

  

  

  

  O.OO02 
  

  

  23 
  

  

  96.80 
  

  

  14.66 
  

  

  12.88 
  

  

  J 
  

  

  0.0003 
  

  

  25 
  

  

  104.50 
  

  

  14-33 
  

  

  14.85 
  

  

  

  0.0005 
  

  

  12 
  

  

  136.15 
  

  

  15-75 
  

  

  6.42 
  

  

  

  O.OOIO 
  

  

  12 
  

  

  99-05 
  

  

  16.45 
  

  

  2.26 
  

  

  _^ 
  _^ 
  

  

  0.0015 
  

  

  14 
  

  

  105.90 
  

  

  18.12 
  

  

  

  7.66 
  

  

  0.0020 
  

  

  19 
  

  

  120.50 
  

  

  17.26 
  

  

  

  2.56 
  

  

  Fig. 
  2 
  it 
  will 
  be 
  seen 
  that 
  very 
  weak 
  zinc 
  sulphate 
  solutions, 
  

   0.0004 
  ^ 
  to 
  0.0015 
  ^f 
  do 
  accelerate 
  the 
  movement 
  in 
  Chara 
  cells. 
  

   The 
  concentration 
  at 
  which 
  the 
  greatest 
  acceleration 
  was 
  observed 
  

   is 
  o.ooi 
  N, 
  the 
  acceleration 
  being 
  20.58 
  per 
  cent 
  of 
  the 
  normal 
  

  

  0.0 
  OCR 
  N 
  

  

  0,0005N 
  

  

  0.O610N 
  

  

  0.0015 
  N 
  

  

  O^GOiiiON 
  

  

  c 
  

  

  0,0003 
  M 
  

  

  Fig. 
  I. 
  Graph 
  showing 
  per 
  cent 
  acceleration 
  (above 
  "Normal" 
  line) 
  and 
  retar- 
  

   dation 
  (below 
  ''Normal" 
  line) 
  of 
  movement 
  in 
  Elodea 
  cells 
  by 
  solutions 
  of 
  zinc 
  sul- 
  

   phate. 
  

  

  rate. 
  Acceleration 
  becomes 
  less 
  below 
  this 
  strength 
  until 
  at 
  

   0.0003 
  N 
  there 
  is 
  no 
  effect 
  at 
  all. 
  Acceleration 
  also 
  falls 
  off 
  as 
  

   the 
  strength 
  increases, 
  until 
  at 
  0.002 
  N 
  there 
  is 
  no 
  effect. 
  Higher 
  

   concentrations 
  were 
  not 
  investigated. 
  

  

  