﻿BuLLEE. 
  — 
  On 
  Eudynamis 
  taitensis. 
  853 
  

  

  Aet. 
  XLIV. 
  — 
  Beivarks 
  nn 
  (he 
  Lovg-tailrd 
  Cuckoo 
  (Eud}aiamis 
  taiteusis). 
  

   By 
  Walter 
  L. 
  Bullek, 
  C.M.G., 
  Sc.D. 
  

   [Read 
  before 
  tJie 
  WelUngton 
  Philosophical 
  Society, 
  Srcl 
  August, 
  1S78.] 
  

   There 
  is 
  a 
  remarkable 
  phenomenon 
  in 
  the 
  animal 
  world 
  known 
  to 
  naturalists 
  

   as 
  " 
  mimicry," 
  or 
  the 
  law 
  of 
  protective 
  resemblance. 
  It 
  is 
  developed 
  chiefly 
  

   among 
  insects, 
  and 
  particularly 
  among 
  the 
  T^epidopera. 
  Mr. 
  Wallace 
  des- 
  

   cribes, 
  at 
  page 
  205 
  of 
  his 
  enchanting 
  book 
  on 
  the 
  " 
  Malay 
  Archipelago," 
  a 
  

   butterfly 
  which, 
  when 
  at 
  rest, 
  so 
  closely 
  resembles 
  a 
  dead 
  leaf 
  as 
  almost 
  to 
  

   defy 
  detection. 
  The 
  varied 
  details 
  of 
  colouring 
  combme 
  to 
  produce 
  a 
  disguise 
  

   that 
  so 
  exactly 
  represents 
  a 
  slightly 
  curved 
  or 
  shrivelled 
  leaf 
  as 
  to 
  render 
  

   the 
  butterfly 
  quite 
  safe 
  from 
  the 
  attacks 
  of 
  insectivorous 
  birds, 
  except 
  when 
  

   on 
  the 
  wing. 
  The 
  flight 
  of 
  the 
  species, 
  on 
  the 
  other 
  hand, 
  is 
  so 
  vigorous 
  

   and 
  rapid 
  that 
  it 
  is 
  well 
  able 
  then 
  to 
  protect 
  itself. 
  Mr. 
  Wallace 
  adds 
  that 
  

   in 
  many 
  specimens 
  there 
  occur 
  patches 
  and 
  spots, 
  formed 
  of 
  small 
  black 
  

   dots, 
  so 
  closely 
  resembling 
  the 
  way 
  in 
  which 
  minute 
  fungi 
  grow 
  on 
  leaves, 
  

   that 
  it 
  is 
  impossible 
  not 
  to 
  believe 
  that 
  fungi 
  have 
  groAvn 
  on 
  the 
  butterflies 
  

   themselves 
  ! 
  This 
  protective 
  imitation 
  must 
  obviously 
  favour 
  the 
  species 
  in 
  

   the 
  common 
  struggle 
  for 
  existence, 
  and 
  may 
  of 
  itself 
  be 
  sufficient 
  to 
  save 
  it 
  

   from 
  extinction. 
  But 
  there 
  is 
  another 
  kind 
  of 
  "mimicry" 
  where 
  one 
  

   insect 
  which 
  would, 
  on 
  discoverj^, 
  be 
  eagerly 
  devoiu'ed, 
  assumes 
  for 
  similar 
  

   protective 
  purposes 
  a 
  close 
  resemblance 
  to 
  some 
  other 
  insect 
  notoriously 
  

   distasteful 
  to 
  birds 
  and 
  reptiles, 
  and 
  often 
  belonging 
  to 
  a 
  totally 
  different 
  

   family 
  or 
  order. 
  Numberless 
  instances 
  might 
  be 
  given 
  in 
  illustration 
  of 
  

   this 
  singular 
  fact, 
  every 
  department 
  furnishing 
  examples 
  of 
  adaptation 
  more 
  

   or 
  less 
  complete, 
  and 
  all 
  being 
  explainable 
  on 
  the 
  principle 
  of 
  variation 
  

   under 
  natural 
  selection 
  or 
  the 
  " 
  survival 
  of 
  the 
  fittest." 
  Mr. 
  Wallace, 
  

   when 
  exploring 
  in 
  the 
  Moluccas, 
  was 
  the 
  first 
  to 
  discover 
  similar 
  instances 
  

   of 
  mimicry 
  among 
  birds, 
  although 
  the 
  law 
  of 
  protective 
  colouring 
  had 
  long 
  

   been 
  observed 
  to 
  exist 
  in 
  the 
  case 
  of 
  birds' 
  eggs. 
  He 
  gives 
  two 
  very 
  curious 
  

   examples 
  of 
  external 
  resemblance, 
  co-existing 
  with 
  very 
  important 
  struc- 
  

   tural 
  differences, 
  rendering 
  it 
  impossible 
  to 
  place 
  the 
  model 
  and 
  the 
  copy 
  

   near 
  each 
  other 
  in 
  any 
  natural 
  arrangement. 
  In 
  one 
  of 
  these 
  a 
  honey- 
  

   sucker 
  has 
  its 
  colours 
  mimicked 
  by 
  a 
  species 
  of 
  oriole, 
  and 
  the 
  reason 
  is 
  

   thus 
  stated: 
  — 
  ■" 
  They 
  must 
  derive 
  some 
  advantage 
  from 
  the 
  imitation, 
  and 
  

   as 
  they 
  are 
  certainly 
  weak 
  birds, 
  with 
  small 
  feet 
  and 
  claws, 
  they 
  may 
  

   require 
  it. 
  Now, 
  the 
  Tropidorhynchi 
  are 
  very 
  strong 
  and 
  active 
  birds, 
  

   having 
  powerful 
  grasping 
  claws, 
  and 
  long, 
  curved, 
  sharp 
  beaks. 
  They 
  

   assemble 
  together 
  in 
  groups 
  and 
  small 
  flocks, 
  and 
  they 
  have 
  a 
  very 
  loud, 
  

   bawling 
  note, 
  Avhich 
  can 
  be 
  heard 
  at 
  a 
  great 
  distance, 
  and 
  serves 
  to 
  collect 
  

  

  a15 
  

  

  