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  BRITISH 
  LEPIDOPTERA. 
  

  

  and 
  Adkinia 
  bipunctidactyla, 
  in 
  the 
  earliest 
  shoots 
  of 
  their 
  focdplants, 
  

   although 
  it 
  must 
  be 
  confessed 
  that 
  they 
  grow 
  very 
  rapidly 
  in 
  their 
  final 
  

   stadia 
  and 
  are 
  also 
  double- 
  brooded. 
  The 
  size 
  of 
  the 
  larva 
  of 
  P. 
  

   calodactyla 
  (zetter 
  steel 
  tii) 
  in 
  spring 
  also 
  suggests 
  a 
  possibility 
  of 
  very 
  early 
  

   spring- 
  (if 
  not 
  winter-) 
  feeding. 
  Still 
  the 
  larvae 
  all 
  appear 
  to 
  go 
  into 
  

   winter-quarters 
  in 
  their 
  second 
  instar. 
  On 
  the 
  other 
  hand, 
  the 
  larvae 
  

   of 
  Stenoptilia 
  fascus, 
  Marasmarcha 
  lunaedactyla, 
  etc., 
  appear 
  to 
  remain 
  

   quite 
  tiny 
  until 
  comparatively 
  late 
  in 
  the 
  spring, 
  and 
  then 
  to 
  feed 
  up 
  

   pretty 
  quickly. 
  Amblyptilia 
  cosmodactyla 
  (acanthodactyla) 
  and 
  A. 
  

   punctidactyla 
  are 
  striking 
  exceptions 
  to 
  this 
  rule, 
  hybernating 
  as 
  

   imagines 
  and 
  laying 
  their 
  eggs 
  apparently 
  in 
  May 
  and 
  June 
  of 
  the 
  

   following 
  year. 
  

  

  Subfamily 
  : 
  Platyptiliin^. 
  

   Tribe 
  : 
  Platyptiliidi. 
  

  

  This 
  tribe 
  is 
  readily 
  recognised 
  in 
  the 
  imaginal 
  stage, 
  by 
  the 
  

   squared 
  outline 
  of 
  the 
  apical 
  area 
  of 
  the 
  forewings, 
  the 
  two 
  lobes 
  of 
  

   which 
  are 
  so 
  far 
  similarly- 
  shaped 
  that 
  each 
  has 
  a 
  distinct 
  and 
  well- 
  

   developed 
  anal 
  angle. 
  In 
  the 
  hindwings 
  the 
  plumules 
  are 
  differently 
  

   shaped, 
  the 
  first 
  fissure 
  being 
  markedly 
  less 
  than 
  the 
  second, 
  whilst 
  

   the 
  third 
  plumule 
  usually 
  carries 
  a 
  tuft 
  of 
  black 
  scales 
  on 
  its 
  hind- 
  

   margin. 
  

  

  "Whether 
  we 
  are 
  accurate 
  in 
  treating 
  these 
  as 
  the 
  most 
  generalised 
  

   of 
  the 
  Platyptiliids 
  or 
  not 
  may 
  be 
  open 
  to 
  question. 
  In 
  the 
  larval 
  stage, 
  

   this 
  tribe 
  most 
  distinctly 
  has 
  the 
  least 
  specialised 
  tubercles, 
  and 
  the 
  

   setae 
  are 
  of 
  the 
  simplest 
  form. 
  It 
  is 
  possible 
  that 
  the 
  earliest 
  plume 
  

   species 
  had 
  larvae 
  that 
  were 
  miners, 
  and 
  that 
  Agdistines 
  and 
  Alucitines 
  

   have 
  specialised 
  farthest 
  away 
  from 
  them 
  as 
  external-feeders 
  in 
  different 
  

   directions, 
  whilst 
  the 
  Stenoptiliids, 
  etc. 
  , 
  retain 
  the 
  habit 
  in 
  the 
  early 
  larval 
  

   stages 
  and 
  specialise 
  in 
  their 
  tubercles 
  towards 
  the 
  Alucitines 
  in 
  the 
  later 
  

   stadia; 
  the 
  Oxyptilids 
  retain, 
  within 
  their 
  limits, 
  larvae 
  of 
  internal-feeding 
  

   habit 
  when 
  young 
  and 
  external 
  when 
  older, 
  and 
  others 
  that 
  are 
  entirely 
  

   external-feeders. 
  Among 
  the 
  Platyptiliids 
  (sens, 
  rest.) 
  we 
  have 
  those 
  

   that 
  have 
  remained 
  miners 
  and 
  have 
  remained 
  simple 
  in 
  their 
  armature 
  

   in 
  consequence. 
  Then, 
  with 
  regard 
  to 
  the 
  secondary 
  hairs, 
  one 
  also 
  

   finds 
  the 
  Platyptiliids 
  differing 
  from 
  the 
  rest 
  ; 
  in 
  the 
  other 
  groups 
  

   these 
  (whether 
  scattered 
  on 
  skin 
  or 
  supplementary 
  in 
  tubercular 
  warts) 
  

   are 
  true 
  hairs, 
  whilst 
  in 
  the 
  Platyptilias 
  they 
  are 
  merely 
  enlarged 
  skin- 
  

   points 
  and 
  not 
  true 
  hairs. 
  

  

  It 
  is 
  to 
  be 
  noted 
  that 
  the 
  larvae 
  of 
  Fredericina 
  have 
  no 
  secondary 
  

   skin-hairs, 
  in 
  that 
  of 
  Platyptilia 
  (isodaetylus) 
  they 
  are 
  wanting 
  on 
  the 
  pale 
  

   areas, 
  whilst 
  in 
  Gillmeria 
  (jjallidactyla) 
  they 
  are 
  numerous. 
  Another 
  

   very 
  important 
  larval 
  character 
  is 
  that, 
  on 
  the 
  meso- 
  and 
  metathorax, 
  

   tubercles 
  i 
  and 
  ii 
  have 
  separate 
  hairs, 
  and 
  are 
  placed 
  in 
  transverse 
  line 
  

   across 
  thorax, 
  as 
  in 
  Agdistids, 
  whilst 
  in 
  all 
  the 
  other 
  Platyptiliines 
  

   (Evcnemidophorns, 
  Amblyptilia, 
  etc.), 
  i 
  and 
  ii 
  are 
  conjoined 
  on 
  thorax 
  

   on 
  either 
  side 
  of 
  median 
  line 
  ; 
  again, 
  iv 
  and 
  v 
  present 
  separate 
  hairs 
  

   on 
  a 
  single 
  plate, 
  not 
  showing 
  the 
  conjoined 
  bases 
  of 
  Eucnemidoplwrus, 
  

   Amblyptilia 
  and 
  Adkinia, 
  nor 
  the 
  further 
  developed 
  wart-like 
  structure 
  

   of 
  Stenoptilia 
  ; 
  further, 
  the 
  accessory 
  post-spiraculars 
  are 
  both 
  absent 
  

   throughout 
  the 
  Platyptilias, 
  nor 
  are 
  there 
  any 
  enlarged 
  secondary 
  

   hairs, 
  whilst 
  the 
  assumed 
  higher 
  Platyptiliids 
  present 
  at 
  least 
  some 
  

   traces 
  of 
  them, 
  being 
  least 
  developed 
  apparently 
  in 
  Adkinia 
  zopJw- 
  

   dactylus. 
  

  

  