﻿480 
  Mr. 
  S. 
  B. 
  J. 
  Skertchly 
  on 
  Butterflies 
  Enemies. 
  

  

  Every 
  English 
  entomologist 
  has 
  noticed 
  similar 
  traits 
  among 
  

   moths, 
  as 
  in 
  the 
  Burnets 
  (Zygcena), 
  the 
  Cinnabar 
  (Euchelia 
  

   jacobcea), 
  the 
  Currant 
  (Abraxas 
  grossulariata) 
  . 
  They 
  are 
  all 
  

   nauseous 
  and 
  all 
  very 
  hard 
  to 
  kill. 
  Among 
  butterflies 
  this 
  is 
  . 
  

   well 
  marked 
  in 
  the 
  genus 
  Danais, 
  and 
  their 
  strong 
  vitality 
  I 
  

   have 
  tested 
  in 
  Southern 
  Europe, 
  Northern 
  Africa, 
  the 
  Straits 
  

   Settlements, 
  Borneo, 
  the 
  Celebes, 
  and 
  the 
  Moluccas. 
  I 
  be- 
  

   lieve 
  that 
  a 
  nauseous 
  secretion 
  and 
  strong 
  vitality 
  always 
  

   go 
  together. 
  

  

  Strong 
  vitality, 
  again, 
  is 
  often 
  correlated 
  with 
  long 
  wings, 
  

   but 
  not 
  with 
  all 
  long-winged 
  butterflies. 
  It 
  occurs 
  in 
  Onii- 
  

   thoptera, 
  Hestia, 
  Idea, 
  Tdeopsts, 
  Eujjlosa, 
  and 
  Danais, 
  but 
  not 
  

   in 
  Neptis 
  and 
  Athyma. 
  Danais 
  possesses 
  both 
  round 
  and 
  

   long-winged 
  species. 
  

  

  These 
  may 
  be 
  tl 
  explained 
  " 
  as 
  correlation, 
  but 
  to 
  me 
  that 
  

   is 
  only 
  an 
  evolutionary 
  shibboleth 
  for 
  " 
  it 
  is, 
  but 
  we 
  don't 
  

   know 
  why." 
  

  

  None 
  of 
  these 
  specially 
  protected 
  forms 
  avoid 
  publicity. 
  

   They 
  flap 
  along, 
  quickly 
  or 
  slowly, 
  but 
  always 
  with 
  a 
  jaunty 
  

   " 
  look 
  at 
  me 
  " 
  sort 
  of 
  air, 
  quite 
  different 
  from 
  such 
  round- 
  

   winged 
  creatures 
  as 
  Papilio, 
  Charaxes, 
  Thaumantes, 
  or 
  

   Melanitis. 
  Surely 
  we 
  see 
  here 
  what 
  might 
  be 
  termed 
  osten- 
  

   tatious 
  protection 
  ! 
  

  

  Contrast 
  these 
  cases 
  with 
  low-flying 
  butterflies 
  like 
  our 
  

   English 
  Browns, 
  the 
  Bornean 
  Yjjthima 
  and 
  Mycalesis. 
  They 
  

   flit 
  along, 
  suddenly 
  pitch, 
  close 
  their 
  wings, 
  and 
  are 
  invisible. 
  

   Often 
  they 
  creep 
  down 
  among 
  grass-roots, 
  and 
  I 
  have 
  seen 
  

   Ypthima 
  hide 
  under 
  stones. 
  So 
  with 
  the 
  " 
  Blues 
  " 
  and 
  

   " 
  Purples 
  " 
  out 
  here. 
  They 
  flash 
  in 
  the 
  sunshine 
  or 
  forest 
  

   shade 
  like 
  rapidly 
  revolving 
  blue 
  lamps. 
  They 
  must 
  be 
  

   seen, 
  or 
  the 
  lovers 
  would 
  never 
  meet 
  ; 
  but 
  it 
  would 
  take 
  an 
  

   active 
  bird, 
  as 
  it 
  does 
  a 
  dexterous 
  naturalist, 
  to 
  catch 
  one. 
  

   When 
  they 
  pitch, 
  down 
  goes 
  the 
  upper 
  wing, 
  and 
  only 
  the 
  

   knife- 
  edged 
  lower 
  wing 
  and 
  tip 
  of 
  upper 
  wing 
  are 
  exposed, 
  

   and 
  a 
  sharp 
  eye 
  alone 
  can 
  see 
  them. 
  All 
  these 
  forms 
  are 
  

   easily 
  killed, 
  and 
  they 
  are 
  undoubtedly 
  protected. 
  

  

  Collating 
  these 
  data, 
  the 
  following 
  inferences 
  seem 
  legiti- 
  

   mate 
  : 
  — 
  

  

  1. 
  The 
  almost 
  universal 
  shyness 
  of 
  butterflies 
  indicates 
  

   fear. 
  

  

  2. 
  The 
  way 
  that 
  shyness 
  is 
  expressed 
  shows 
  fear 
  of 
  

   moving 
  objects. 
  

  

  3. 
  The 
  theory 
  of 
  mimicry 
  presupposes 
  («) 
  that 
  danger 
  

   is 
  universal, 
  (b) 
  that 
  some 
  butterflies 
  escape 
  danger 
  by 
  

  

  