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  PROCEEDINGS 
  OF 
  THE 
  FOUJMH 
  ENTOMOLOGICAL 
  MEETING 
  

  

  this 
  was 
  doubtless 
  its 
  condition 
  before 
  tbe 
  evolution 
  of 
  the 
  mimetic 
  

   forms. 
  There 
  is 
  no 
  reason 
  to 
  suppose 
  that 
  the 
  surviving 
  percentage 
  

   of 
  polytes 
  was 
  increased 
  by 
  the 
  presence 
  of 
  the 
  aristolochice 
  model 
  or 
  

   during 
  the 
  growth 
  of 
  the 
  mimetic 
  likeness. 
  All 
  that 
  happened 
  was 
  

   this 
  : 
  — 
  Certain 
  variations 
  formerly 
  unselected, 
  now 
  tend 
  to 
  fall 
  into 
  the 
  

   surviving 
  percentage, 
  and, 
  once 
  started, 
  the 
  further 
  stages 
  of 
  transfor- 
  

   mation 
  were 
  effected 
  in 
  the 
  same 
  way. 
  Each 
  change 
  that 
  suggested 
  

   still 
  more 
  strongly 
  an 
  advertisement 
  common 
  to 
  a 
  far 
  more 
  distasteful 
  

   form 
  would 
  tend 
  to 
  be 
  selected. 
  So 
  too, 
  when 
  polytes 
  spreads 
  beyond 
  

   the 
  range 
  of 
  aristolochice, 
  or 
  when 
  the 
  model 
  for 
  some 
  reason 
  disappears 
  

   from 
  an 
  area 
  in 
  which 
  folytes 
  is 
  abundant, 
  the 
  constitution, 
  not 
  the 
  

   amount, 
  of 
  the 
  surviving 
  percentage 
  is 
  changed. 
  The 
  mimetic 
  pattern 
  

   soon 
  disappears, 
  although 
  the 
  species 
  that 
  bore 
  it 
  remains 
  as 
  abundant 
  

   as 
  before. 
  The 
  survival 
  or 
  extinction 
  of 
  the 
  species 
  is 
  not 
  afiected 
  : 
  

   all 
  that 
  has 
  happened 
  is 
  the 
  survival 
  or 
  extinction 
  of 
  a 
  pattern 
  borne 
  

   by 
  a 
  certain 
  proportion 
  of 
  the 
  individuals 
  of 
  the 
  species. 
  When 
  these 
  

   disappear 
  other 
  individuals 
  with 
  another 
  pattern 
  take 
  their 
  place. 
  It 
  

   is, 
  furthermore, 
  extremely 
  probable 
  that 
  selection 
  is 
  reversed 
  when 
  

   the 
  models 
  are 
  absent, 
  for 
  a 
  female 
  that 
  resembles 
  the 
  male 
  is 
  better 
  

   advertised 
  than 
  one 
  which 
  resembles 
  a 
  non-existent 
  model. 
  Although 
  

   I 
  believe 
  that 
  many 
  mimicking 
  species 
  bear 
  the 
  above-described 
  relation- 
  

   ship 
  to 
  their 
  models, 
  I 
  do 
  not 
  mean 
  to 
  imply 
  that 
  this 
  is 
  always 
  so. 
  

   No 
  doubt 
  there 
  are 
  plenty 
  of 
  mimicking 
  species 
  which 
  depend 
  upon 
  

   the 
  presence 
  of 
  the 
  model 
  for 
  their 
  existence 
  and 
  could 
  not 
  live 
  in 
  areas 
  

   from 
  which 
  the 
  model 
  disappeared." 
  

  

  I 
  should 
  perhaps, 
  add 
  that 
  we 
  can 
  well 
  understand 
  the 
  advantage 
  

   of 
  a 
  mimetic 
  pattern, 
  even 
  when 
  accompanied 
  by 
  great 
  differences 
  in 
  

   flight 
  and 
  behaviour, 
  if 
  we 
  look 
  upon 
  it 
  as 
  an 
  aid 
  to 
  memory 
  of 
  enemies, 
  

   helping 
  them 
  to 
  recall 
  an 
  unpleasant 
  experience, 
  rather 
  than 
  as 
  the 
  

   deceptive 
  resemblance 
  of 
  a 
  palatable 
  eagerly 
  sought-for 
  species 
  to 
  one 
  

   unpalatable 
  and 
  avoided. 
  Furthermore 
  the 
  difference 
  in 
  flight 
  means 
  

   for 
  polytes 
  powers 
  of 
  escape 
  from 
  those 
  enemies 
  which 
  would 
  devour 
  

   it 
  but 
  not 
  its 
  model. 
  

  

  North 
  Kanara 
  District. 
  J. 
  Davidson, 
  T. 
  R. 
  Bell 
  and 
  E. 
  H. 
  Aitken. 
  

   (Vol. 
  X, 
  1895-97, 
  p. 
  580). 
  " 
  P. 
  polytes 
  : 
  This 
  is 
  very 
  common 
  and 
  very 
  

   destructive 
  to 
  orange 
  and 
  lime 
  trees 
  in 
  gardens 
  " 
  

  

  The 
  Konhan. 
  E. 
  H. 
  Aitken 
  and 
  E. 
  Comber. 
  (Vol. 
  XV, 
  1903-04, 
  

   p. 
  52) 
  " 
  Papilio 
  pammon, 
  L. 
  Quite 
  common 
  all 
  over 
  the 
  district. 
  Of 
  

   the 
  several 
  forms 
  of 
  females 
  the 
  polytes 
  type, 
  which 
  resembles 
  P. 
  aris- 
  

   tolochice, 
  is 
  the 
  commonest 
  and 
  the 
  romulus 
  type 
  is 
  not 
  rare, 
  but 
  we 
  

   have 
  no 
  record 
  of 
  the 
  form 
  that 
  is 
  similar 
  to 
  the 
  male." 
  

  

  