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  the 
  hindwing 
  of 
  the 
  ^ 
  , 
  this 
  suffusion, 
  combined 
  with 
  unusual 
  

   breadth 
  of 
  border, 
  occasionally 
  leaves 
  only 
  a 
  minute 
  area 
  of 
  the 
  

   ground 
  colour 
  visible. 
  On 
  the 
  other 
  hand 
  it 
  will 
  be 
  seen, 
  in 
  the 
  

   series 
  I 
  exhibit 
  this 
  evening, 
  that 
  in 
  Swiss 
  and 
  even 
  more 
  markedly 
  

   in 
  Italian 
  specimens, 
  the 
  ground 
  colour, 
  especially 
  in 
  the 
  ? 
  s, 
  fills 
  

   the 
  larger 
  part 
  of 
  the 
  area 
  of 
  the 
  wing, 
  an 
  effect 
  enhanced 
  by 
  the 
  

   much 
  lighter 
  colour 
  of 
  the 
  suffusion 
  itself. 
  With 
  regard 
  to 
  the 
  

   underside, 
  the 
  only 
  noticeable 
  colour-variation 
  on 
  the 
  forewing 
  is 
  the 
  

   greater 
  or 
  less 
  extent 
  to 
  which 
  the 
  FJ 
  rebia-like 
  band 
  just 
  inside 
  the 
  

   margin 
  is 
  visible. 
  In 
  some 
  specimens 
  there 
  is 
  no 
  trace 
  of 
  it, 
  in 
  

   others 
  it 
  is 
  clearly 
  visible 
  just 
  round, 
  or 
  just 
  above, 
  the 
  eye-spot, 
  

   while 
  in 
  some 
  it 
  is 
  clearly 
  indicated 
  all 
  down 
  the 
  wing 
  ; 
  in 
  one 
  

   specimen 
  of 
  my 
  series 
  (unfortunately 
  slightly 
  damaged) 
  it 
  is 
  very 
  

   pronounced. 
  On 
  the 
  hindwing 
  the 
  presence 
  or 
  absence 
  of 
  strong 
  

   contrast 
  between 
  the 
  light 
  and 
  dark 
  portions 
  gives 
  rise 
  to 
  wide 
  

   variation. 
  In 
  the 
  Tavistock 
  specimens 
  it 
  is 
  very 
  marked, 
  whilst 
  in 
  

   the 
  Italian 
  it 
  is 
  very 
  slight, 
  the 
  normal 
  dark 
  colouring 
  being 
  only 
  a 
  

   shade 
  or 
  two 
  darker 
  than 
  the 
  lighter 
  portion. 
  In 
  the 
  little 
  Spanish 
  

   specimen 
  exhibited, 
  this 
  approximation 
  of 
  the 
  two 
  shades 
  is 
  carried 
  

   still 
  further. 
  In 
  the 
  <? 
  s 
  from 
  near 
  Lake 
  Maggiore 
  the 
  darker 
  

   colour 
  so 
  far 
  invades 
  the 
  area 
  of 
  the 
  lighter 
  as 
  almost 
  to 
  obliterate 
  it. 
  

   By 
  far 
  the 
  most 
  remarkable 
  mode 
  of 
  variation 
  is 
  however 
  the 
  

   spotting 
  of 
  both 
  wings 
  and 
  on 
  both 
  surfaces. 
  Normally 
  there 
  is 
  on 
  

   each 
  side 
  of 
  the 
  forewing 
  a 
  single 
  black 
  double-pupilled 
  spot, 
  and 
  on 
  

   the 
  upper 
  side 
  of 
  the 
  hindwing 
  a 
  single-pupilled 
  spot 
  near 
  the 
  anal 
  

   angle, 
  not 
  unusually 
  accompanied, 
  especially 
  in 
  the 
  ? 
  , 
  by 
  another 
  

   small 
  spot 
  in 
  the 
  next 
  inter-neural 
  space 
  above 
  it. 
  On 
  the 
  under- 
  

   side 
  of 
  the 
  hindwing 
  is 
  a 
  variable 
  number 
  of 
  white 
  points, 
  the 
  most 
  

   conspicuous 
  of 
  which 
  are 
  usually 
  those 
  in 
  the 
  2nd, 
  5th 
  and 
  6th 
  

   interneural 
  spaces 
  counting 
  from 
  the 
  costa. 
  The 
  variation 
  in 
  

   spotting 
  may 
  be 
  either 
  in 
  the 
  direction 
  of 
  addition 
  or 
  diminution. 
  

   The 
  double-pupilled 
  eye-spot 
  on 
  the 
  forewing 
  frequently 
  has 
  the 
  

   lower 
  pupil 
  almost, 
  and 
  sometimes 
  quite, 
  obliterated 
  both 
  above 
  and 
  

   below 
  ; 
  occasionally 
  the 
  upper 
  pupil 
  also 
  disappears, 
  forming 
  the 
  ab. 
  

   caeca, 
  Tutt 
  ; 
  the 
  anal 
  eye-spot 
  on 
  the 
  hindwing 
  is 
  not 
  infrequently 
  

   wanting 
  in 
  the 
  g 
  ; 
  sometimes 
  also 
  the 
  black 
  spot 
  disappears 
  

   leaving 
  a 
  conspicuous 
  white 
  pupil. 
  Instances 
  may 
  be 
  seen 
  in 
  the 
  

   series 
  I 
  exhibit, 
  and 
  more 
  pronounced 
  instances 
  of 
  the 
  conspicuous 
  

   white 
  spot 
  are 
  in 
  the 
  collection 
  exhibited 
  here 
  by 
  Mr. 
  Stiff'. 
  

  

  When 
  extra 
  spots 
  appear 
  on 
  the 
  forewing 
  it 
  is 
  remarkable 
  that 
  

   two 
  are 
  considerably 
  more 
  frequent 
  than 
  one. 
  These 
  appear 
  in 
  the 
  

   two 
  interneural 
  spaces 
  next 
  below 
  the 
  usual 
  spot 
  ; 
  they 
  vary 
  in 
  size 
  

   from 
  the 
  smallest 
  dots 
  to 
  large 
  well-pupilled 
  eye-spots, 
  but 
  very 
  

   small 
  spots 
  are 
  sometimes 
  pupilled 
  and 
  fairly 
  large 
  ones 
  occasionally 
  

   blind 
  ; 
  generally 
  speaking 
  the 
  lower 
  spot 
  is 
  the 
  larger 
  if 
  there 
  is 
  any 
  

   difference 
  in 
  size, 
  but 
  this, 
  which 
  might, 
  for 
  reasons 
  referred 
  to 
  later, 
  

   have 
  been 
  expected 
  to 
  occur 
  almost 
  universally, 
  is 
  by 
  no 
  means 
  an 
  

   invariable 
  rule. 
  When 
  only 
  one 
  extra 
  spot 
  occurs 
  it 
  may 
  be 
  either 
  

  

  