﻿( 
  xxxviii 
  ) 
  

  

  upon 
  the 
  stem 
  and 
  leaves 
  of 
  their 
  food-plant. 
  Mr. 
  Poulton 
  

   said 
  that 
  he 
  had 
  also 
  found 
  that 
  dark 
  cocoons 
  may 
  be 
  formed 
  

   in 
  spite 
  of 
  the 
  excessive 
  disturbance 
  caused 
  by 
  an 
  investiga- 
  

   tion 
  into 
  the 
  mode 
  of 
  construction. 
  Mr. 
  Bateson's 
  results, 
  

   if 
  due 
  to 
  disturbance, 
  are 
  not 
  necessarily 
  destructive 
  of 
  the 
  

   conclusions 
  previously 
  arrived 
  at. 
  The 
  glittering 
  pupae 
  of 
  

   V.anessidcB 
  may 
  be 
  produced, 
  in 
  healthy 
  individuals, 
  by 
  exposing 
  

   the 
  mature 
  larvffi 
  to 
  white 
  or 
  gilt 
  surroundings, 
  but 
  they 
  are 
  

   also 
  caused 
  by 
  the 
  presence 
  of 
  parasites. 
  In 
  the 
  case 
  of 
  E. 
  

   lanestris 
  it 
  must 
  be 
  freely 
  admitted 
  that 
  Mr. 
  Bateson's 
  results 
  

   prove 
  that 
  the 
  evidence 
  previously 
  relied 
  upon 
  is 
  insufficient, 
  

   and 
  further 
  indicate 
  that, 
  if 
  the 
  species 
  is 
  sensitive 
  to 
  the 
  

   <;olour 
  of 
  its 
  surroundings 
  in 
  the 
  manner 
  hitherto 
  assumed, 
  its 
  

   susceptibility 
  is 
  not 
  nearly 
  so 
  great 
  as 
  was 
  supposed. 
  Further 
  

   experiments 
  must 
  show 
  whether 
  any 
  trace 
  of 
  susceptibility 
  to 
  

   colour 
  exists. 
  

  

  Mr. 
  Poulton 
  further 
  stated 
  that 
  in 
  such 
  experiments 
  upon 
  

   this 
  and 
  other 
  species 
  it 
  would 
  be 
  well 
  to 
  test 
  Mr. 
  Bateson's 
  

   suggestion 
  by 
  frequently 
  disturbing 
  and 
  insufficiently 
  feeding 
  

   larvae, 
  which 
  are 
  then 
  allowed 
  to 
  spin 
  on 
  the 
  food-plant 
  ; 
  

   ■furthermore, 
  in 
  the 
  case 
  of 
  colours, 
  it 
  would 
  be 
  ad-sdsable 
  

   to 
  employ 
  more 
  natural 
  backgrounds 
  than 
  paper, 
  muslin, 
  &c. 
  

   Earth, 
  sand, 
  peat, 
  chalk, 
  coal, 
  leaves 
  and 
  twigs 
  of 
  various 
  

   tints 
  and 
  shades, 
  might 
  be 
  used. 
  It 
  must 
  also 
  be 
  admitted 
  

   that 
  the 
  evidence 
  in 
  the 
  case 
  of 
  Halias 
  prasinana, 
  Liparis 
  

   nuriflua, 
  and 
  Piuinia 
  cratagata, 
  which 
  appeared 
  sufficient 
  when 
  

   ■Mr. 
  Newman's 
  results 
  with 
  E. 
  lanestris 
  seemed 
  to 
  be 
  con- 
  

   vincing, 
  is 
  now 
  inadequate, 
  and 
  new 
  experiments, 
  upon 
  a 
  

   far 
  larger 
  scale, 
  must 
  be 
  conducted. 
  Mr. 
  Poulton 
  thought 
  

   that 
  in 
  the 
  case 
  of 
  Saturnia 
  carpini, 
  Mr. 
  Bateson's 
  evidence 
  is 
  

   weaker, 
  and 
  that 
  which 
  supports 
  the 
  earlier 
  conclusions 
  

   stronger, 
  than 
  in 
  the 
  case 
  of 
  E. 
  lanestris. 
  At 
  the 
  same 
  time, 
  

   it 
  is 
  by 
  no 
  means 
  impossible 
  that 
  starvation 
  or 
  extreme 
  

   disturbance 
  may 
  tend 
  to 
  produce 
  light 
  cocoons, 
  even 
  if 
  these 
  

   •are 
  also 
  caused 
  by 
  light 
  surroundings. 
  The 
  harmony 
  between 
  

   the 
  colour 
  of 
  these 
  cocoons 
  and 
  their 
  surroundings 
  had 
  been 
  

   -observed 
  by 
  many 
  naturalists. 
  Mr. 
  Poulton 
  remarked 
  that 
  

   •Mr. 
  A. 
  K. 
  Wallace 
  alluded 
  to 
  it 
  in 
  ' 
  Tropical 
  Nature,' 
  and 
  

   ■that 
  Mr. 
  W. 
  H. 
  Harwood, 
  of 
  Colchester, 
  had 
  called 
  his 
  

  

  