﻿202 
  BRITISH 
  LEPIDOPTERA. 
  

  

  to 
  be 
  the 
  gonodactyla 
  of 
  Schiffermiiller 
  and 
  Denis, 
  is 
  of 
  a 
  brownish 
  -grey- 
  

   tint, 
  about 
  as 
  large 
  as 
  P. 
  tetradactyla. 
  The 
  forewing 
  is 
  divided 
  into 
  

   two 
  lobes 
  by 
  a 
  longitudinal 
  fissure 
  for 
  the 
  first 
  third 
  of 
  its 
  length 
  ; 
  at 
  

   the 
  termination 
  of 
  the 
  cleft 
  (on 
  the 
  costa) 
  stands 
  a 
  triangular 
  brown 
  

   spot 
  ; 
  the 
  inner 
  margin 
  of 
  the 
  exterior 
  part 
  (or 
  ' 
  Spitzenlappens 
  ') 
  is, 
  like 
  

   the 
  inner 
  margin 
  of 
  the 
  forewing 
  itself, 
  edged 
  with 
  whitish. 
  The 
  

   hind 
  wings 
  are 
  composed 
  of 
  three 
  plumules, 
  fringed 
  only 
  on 
  their 
  inner 
  

   margins."] 
  

  

  Imago. 
  — 
  21mm. 
  -27mm. 
  Head, 
  thorax 
  and 
  abdomen 
  of 
  the 
  same 
  

   colour 
  as 
  the 
  wings. 
  Anterior 
  wings 
  divided 
  into 
  two 
  lobes 
  ; 
  the 
  apex 
  

   sharply 
  angulated 
  but 
  not 
  much 
  produced 
  ; 
  the 
  ground 
  colour 
  whitish- 
  

   grey, 
  the 
  costal 
  area 
  darker, 
  being 
  sprinkled 
  with 
  dark 
  scales 
  ; 
  the 
  

   inner 
  margin 
  also 
  darker 
  at 
  the 
  base, 
  but 
  paler 
  in 
  centre 
  and 
  towards 
  

   anal 
  angle 
  ; 
  in 
  this 
  pale 
  part 
  there 
  are 
  generally 
  two 
  dark 
  marks 
  on 
  

   the 
  inner 
  margin, 
  variable 
  in 
  shape, 
  one 
  near 
  the 
  centre, 
  the 
  other 
  nearer 
  

   the 
  anal 
  angle 
  ; 
  the 
  central 
  area 
  comparatively 
  clear 
  ; 
  a 
  dark 
  brown 
  

   triangular 
  blotch 
  on 
  costa 
  (just 
  within 
  cleft) 
  is 
  produced 
  almost 
  to 
  

   inner 
  margin, 
  and 
  externally 
  edged 
  by 
  a 
  pale 
  line, 
  forming 
  roughly 
  a 
  

   lunular 
  mark 
  ; 
  a 
  dark 
  shade, 
  hardly 
  to 
  be 
  called 
  a 
  band, 
  crosses 
  the 
  

   two 
  lobes 
  parallel 
  to 
  the 
  outer 
  margin, 
  edged 
  externally 
  by 
  another 
  

   very 
  pale 
  line. 
  Posterior 
  wings 
  divided 
  into 
  three 
  plumules, 
  of 
  a 
  

   greyish 
  -brown 
  colour, 
  with 
  paler 
  fringes, 
  the 
  posterior 
  plumule 
  with 
  a 
  

   distinct 
  tuft 
  of 
  black 
  scales 
  towards 
  the 
  anal 
  angle. 
  

  

  Variation. 
  — 
  The 
  newly-emerged 
  imagines 
  differ 
  considerably 
  in 
  

   ground 
  colour 
  and 
  intensity 
  of 
  markings 
  ; 
  some 
  are 
  distinctly 
  whitish 
  - 
  

   grey 
  in 
  ground 
  colour, 
  others 
  strongly 
  reddish-ochreous, 
  whilst 
  many 
  

   are 
  strongly 
  suffused 
  with 
  a 
  rosy 
  tint. 
  The 
  strength 
  of 
  the 
  markings, 
  

   too, 
  varies 
  considerably, 
  some 
  being 
  faintly, 
  others 
  quite 
  darkly, 
  

   marked. 
  In 
  some 
  specimens, 
  principally 
  of 
  the 
  early 
  brood, 
  the 
  

   ground 
  colour 
  is 
  slaty-grey, 
  the 
  markings 
  very 
  rich 
  brown, 
  the 
  costal 
  and 
  

   inner 
  margins 
  much 
  speckled 
  with 
  ochreous, 
  and 
  thus 
  these 
  specimens 
  

   somewhat 
  resemble 
  the 
  more 
  richly 
  marked 
  F. 
  calodactyla. 
  On 
  the 
  

   whole, 
  there 
  is 
  much 
  more 
  variation 
  in 
  the 
  first 
  than 
  in 
  the 
  second 
  broody 
  

   the 
  specimens 
  of 
  the 
  early 
  brood 
  being, 
  generally, 
  much 
  redder 
  and 
  

   more 
  strongly 
  marked 
  than 
  those 
  of 
  the 
  later 
  brood, 
  a 
  pale 
  whitish-grey 
  

   example 
  being 
  rare 
  in 
  the 
  spring 
  brood, 
  whilst 
  in 
  the 
  autumnal 
  brood 
  

   a 
  reddish 
  or 
  ochreous 
  specimen 
  is 
  of 
  rare 
  occurrence, 
  almost 
  all 
  being 
  

   conspicuously 
  pale. 
  Not 
  only 
  are 
  the 
  second 
  brood 
  examples 
  paler 
  r 
  

   but 
  they 
  are 
  generally 
  smaller 
  and 
  not 
  so 
  decidedly 
  marked, 
  the 
  earlier 
  

   specimens 
  of 
  this 
  brood 
  especially 
  having 
  a 
  bleached 
  appearance 
  ; 
  the 
  

   colour 
  too 
  appears 
  to 
  be 
  of 
  a 
  more 
  uniform 
  grey, 
  and 
  the 
  markings 
  also 
  

   are 
  less 
  sharp 
  than 
  in 
  most 
  specimens 
  of 
  the 
  first 
  brood, 
  the 
  bleached 
  

   appearance 
  being 
  possibly 
  due 
  to 
  the 
  fact 
  that 
  the 
  larvae 
  hurry 
  through 
  their 
  

   changes 
  compared 
  with 
  those 
  of 
  the 
  first 
  brood. 
  There 
  is 
  also 
  a 
  great 
  

   deal 
  of 
  variation 
  in 
  size, 
  those 
  of 
  the 
  early 
  brood 
  being 
  generally 
  the 
  

   larger, 
  although 
  very 
  large 
  and 
  very 
  small 
  examples 
  occur 
  in 
  both 
  

   broods. 
  Borgmann 
  notes 
  that 
  he 
  reared 
  examples 
  from 
  larvae 
  in 
  the 
  

   flowerheads 
  of 
  Tussilago 
  at 
  Cassel, 
  in 
  1878, 
  that 
  were 
  nearly 
  one-third 
  

   larger 
  than 
  the 
  autumnal 
  specimens. 
  There 
  appears 
  to 
  be 
  little, 
  if 
  

   any, 
  fixed 
  sexual 
  variation 
  in 
  colour 
  or 
  size. 
  Some 
  individuals, 
  one 
  

   notices, 
  have 
  only 
  one, 
  or 
  neither, 
  of 
  the 
  two 
  dark 
  spots 
  normally 
  present 
  

   on 
  the 
  inner 
  margin 
  ; 
  some 
  have 
  a 
  dark 
  shading 
  at 
  the 
  exterior 
  edges 
  of 
  

   the 
  cleft 
  in 
  the 
  anterior 
  wings, 
  whilst 
  others 
  are 
  without 
  it, 
  and 
  yet 
  again 
  

  

  