﻿224 
  BRITISH 
  LEPIDOPTERA. 
  

  

  hindwings 
  are 
  similar 
  in 
  tint, 
  rusty- 
  brown, 
  and 
  the 
  fringes 
  of 
  each 
  

   feather 
  are 
  light 
  yellow 
  at 
  base 
  and 
  darker 
  at 
  apex, 
  but 
  in 
  a 
  less 
  marked 
  

   degree 
  than 
  in 
  ochrodactyla, 
  in 
  which 
  the 
  fringes 
  have 
  a 
  spotted 
  

   appearance 
  from 
  the 
  strong 
  contrast 
  of 
  the 
  bright 
  yellow 
  and 
  dark 
  

   brown 
  ; 
  in 
  correspondence 
  with 
  this, 
  the 
  scale-tuft 
  on 
  the 
  3rd 
  feather 
  

   of 
  the 
  hindwing 
  is 
  sharply 
  marked 
  with 
  dark 
  brown 
  in 
  ochrodactyla, 
  

   whilst 
  it 
  only 
  shows 
  a 
  slight 
  darkening 
  in 
  colour 
  in 
  pallidactyla. 
  He 
  

   agrees, 
  however, 
  with 
  Miihlig 
  (Stett. 
  Ent. 
  Zeitg., 
  1863, 
  p. 
  213) 
  that 
  the 
  

   most 
  essential 
  difference 
  occurs 
  in 
  the 
  colour 
  of 
  the 
  hind-legs 
  ; 
  in 
  ten 
  

   specimens 
  of 
  pallidactyla 
  examined, 
  the 
  two 
  terminal 
  unspurred 
  joints 
  

   are 
  unicolorous 
  yellowish-white, 
  whilst 
  the 
  two 
  upper 
  spurred 
  joints 
  

   are 
  unicolorous 
  rusty-brown, 
  with 
  white 
  spurs 
  ; 
  only 
  towards 
  the 
  knee 
  

   (trochanter) 
  does 
  the 
  colour 
  become 
  gradually 
  lighter. 
  Staintonadds 
  [Ent. 
  

   Mo. 
  Mag., 
  ii., 
  pp. 
  137-138) 
  that, 
  in 
  ochrodactyla, 
  the 
  apex 
  of 
  the 
  anterior 
  

   wings 
  is 
  more 
  prolonged, 
  more 
  falcate 
  than 
  in 
  pallidactyla 
  (bertr 
  -ami), 
  and 
  

   the 
  brown 
  scales 
  on 
  the 
  hind 
  margin 
  of 
  the 
  third 
  feather 
  of 
  the 
  posterior 
  

   wings 
  should 
  be 
  more 
  distinct. 
  The 
  best 
  character 
  is, 
  however, 
  furnished 
  

   by 
  the 
  hindlegs 
  ; 
  in 
  bertrami 
  the 
  tibiae 
  are 
  slightly 
  browned, 
  but 
  the 
  tarsi 
  

   are 
  spotless 
  whitish 
  ; 
  in 
  ochrodactyla 
  (dichrodactylus) 
  the 
  tibiae 
  are 
  brown 
  

   at 
  the 
  middle 
  and 
  apex, 
  and 
  there 
  is 
  a 
  brown 
  spot 
  at 
  the 
  end 
  of 
  the 
  

   1st 
  tarsal 
  joint. 
  These 
  three 
  dark 
  spots 
  have, 
  in 
  bred 
  specimens, 
  a 
  

   very 
  conspicuous 
  appearance 
  (Stainton). 
  Jordan 
  writes 
  (Ent. 
  Mo. 
  Mag., 
  

   xviii., 
  pp. 
  75-6) 
  that 
  a 
  specimen 
  of 
  ochrodactyla, 
  bred' 
  from 
  Tanacetiuii 
  t 
  

   from 
  Scarborough, 
  in 
  his 
  possession, 
  has 
  a 
  most 
  decided 
  black 
  spot 
  just 
  

   above 
  and 
  near 
  the 
  end 
  of 
  the 
  split, 
  and 
  surmises 
  that 
  Packard's 
  

   cervinidactylus 
  (Ann. 
  Lye. 
  N. 
  Y., 
  x., 
  p. 
  266) 
  may 
  have 
  been 
  described 
  

   from 
  such 
  a 
  specimen. 
  He 
  further 
  states 
  that 
  this 
  is 
  the 
  brightest 
  in 
  

   a 
  long 
  series, 
  and 
  has 
  long 
  falcate 
  anterior 
  wings, 
  whilst 
  on 
  the 
  other 
  

   hand, 
  a 
  type 
  from 
  Miihlig, 
  the 
  author 
  of 
  the 
  name 
  dichrodactylus 
  (for 
  

   the 
  Tanacetum 
  feeder), 
  is 
  very 
  light 
  in 
  colour, 
  and 
  the 
  anterior 
  lobe 
  

   truncate, 
  without 
  any 
  approach 
  to 
  the 
  falcate 
  form 
  of 
  the 
  former 
  speci- 
  

   men. 
  He 
  says 
  that 
  he 
  cannot 
  see 
  any 
  distinct 
  dividing 
  line 
  between 
  the 
  

   richly 
  fawn-yellow 
  specimens 
  with 
  falcate 
  wings, 
  and 
  the 
  pale 
  straw- 
  

   coloured 
  insects 
  with 
  the 
  apex 
  as 
  square 
  as 
  in 
  gonodactyla 
  ; 
  the 
  extremes 
  

   of 
  the 
  series 
  look 
  most 
  distinct, 
  but 
  the 
  gradations 
  are 
  such 
  as 
  to 
  make 
  

   it 
  very 
  difficult 
  to 
  draw 
  the 
  boundary 
  line. 
  He 
  quotes 
  Stainton, 
  who 
  

   says 
  (Ent. 
  Mo. 
  Mag., 
  ii., 
  p. 
  138) 
  that 
  " 
  the 
  best 
  character 
  is 
  furnished 
  

   by 
  the 
  hindlegs, 
  for, 
  in 
  bertrami 
  the 
  tibiae 
  are 
  slightly 
  browned, 
  but 
  the 
  

   tarsi 
  are 
  spotless 
  whiti 
  sh, 
  whilst 
  in 
  dich 
  rodactylus 
  the 
  tibiae 
  are 
  brown 
  at 
  the 
  

   middle 
  and 
  apex, 
  and 
  there 
  is 
  a 
  brown 
  spot 
  at 
  the 
  end 
  of 
  the 
  1st 
  tarsal 
  

   joint." 
  He 
  further 
  notes 
  that 
  Heinemann 
  makes 
  (Schmett. 
  Deutsch., 
  

   ii., 
  p. 
  784) 
  "bertrami 
  very 
  close 
  to 
  dichrodactyla, 
  but 
  that 
  theforewings 
  

   of 
  the 
  former 
  are 
  less 
  sharply 
  pointed, 
  all 
  the 
  brownish-red 
  dusting 
  

   paler, 
  the 
  spots 
  before 
  the 
  division 
  pale, 
  often 
  entirely 
  wanting, 
  the 
  

   lines 
  at 
  the 
  hind 
  border 
  finer, 
  whilst, 
  on 
  the 
  3rd 
  feather 
  of 
  the 
  hind- 
  

   wing, 
  the 
  black 
  scales 
  behind 
  the 
  middle 
  are 
  either 
  less 
  or 
  wanting 
  ; 
  

   the 
  legs 
  are 
  yellowish-white, 
  the 
  tibiae 
  of 
  the 
  forelegs 
  are 
  brown 
  at 
  the 
  

   end, 
  in 
  the 
  hind 
  tibiae 
  the 
  reddish-brown 
  colour 
  is 
  equally 
  spread 
  from 
  

   the 
  middle 
  to 
  the 
  end." 
  Jordan 
  states 
  that 
  these 
  slight 
  distinctions 
  

   seem 
  certainly 
  inconstant 
  in 
  apparently 
  fine 
  examples, 
  and 
  further 
  

   adds 
  that 
  he 
  has 
  a 
  specimen 
  from 
  Walsingham 
  before 
  him, 
  from 
  a 
  pupa 
  

   found 
  on 
  Artemisia 
  campestris, 
  which 
  has 
  for 
  bertrami 
  remarkably 
  

   pointed 
  wings. 
  Sang, 
  who 
  knew 
  the 
  species 
  better 
  perhaps 
  than 
  an)" 
  

  

  