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  BRITISH 
  LEPIDOPTERA. 
  

  

  characters, 
  the 
  Stenoptiliines 
  appear 
  to 
  be 
  the 
  most 
  generalised, 
  the 
  

   Oxyptiliines 
  the 
  most 
  specialised. 
  Chapman 
  considers, 
  however, 
  for 
  

   various 
  reasons, 
  that 
  the 
  Platyptiliines 
  are 
  the 
  most 
  generalised 
  of 
  the 
  

   family. 
  He 
  bases 
  his 
  opinion 
  on 
  the 
  following 
  details 
  : 
  (1) 
  The 
  larval 
  

   tubercles 
  in 
  structure 
  and 
  arrangement 
  come 
  nearest 
  to 
  those 
  of 
  

   the 
  Agdistids. 
  (2) 
  The 
  pupa 
  is 
  nearest 
  to 
  the 
  Agdistids 
  in 
  smooth- 
  

   ness, 
  form, 
  etc., 
  also, 
  though 
  it 
  has 
  the 
  dorso-lateral 
  keels 
  very 
  

   highly 
  marked, 
  they 
  are 
  of 
  the 
  simplest 
  structure 
  and 
  carry 
  no 
  special 
  

   developments 
  of 
  the 
  tubercles 
  on 
  them. 
  (3) 
  The 
  imago 
  has 
  the 
  most 
  

   marked 
  hind-margins, 
  their 
  ancestors, 
  no 
  doubt, 
  had 
  good 
  hind- 
  

   margins 
  ; 
  these 
  fail 
  a 
  good 
  deal 
  in 
  the 
  Stenoptiliids, 
  more 
  so 
  in 
  the 
  

   Oxyptiliids, 
  where 
  they 
  are 
  sometimes 
  very 
  like 
  the 
  Alucitines. 
  

  

  Throughout 
  the 
  family, 
  as 
  already 
  noted, 
  the 
  ovum 
  tends 
  to 
  a 
  rather 
  

   cylindrical 
  outline. 
  The 
  larvae, 
  too, 
  both 
  internal-feeding 
  and 
  external- 
  

   feeding, 
  have 
  a 
  more 
  cylindrical 
  form 
  than 
  those 
  of 
  the 
  Alucitids. 
  

   In 
  the 
  Platyptiliines 
  the 
  larval 
  tubercles 
  are 
  of 
  a 
  very 
  simple 
  character, 
  

   comparatively 
  so 
  also 
  in 
  the 
  Amblyptiliines 
  and 
  Stenoptiliines 
  but 
  

   these 
  develop 
  into 
  more 
  or 
  less 
  complicated 
  warts 
  in 
  the 
  Oxyptilines, 
  

   in 
  which, 
  in 
  its 
  highest 
  forms, 
  i 
  and 
  ii 
  form 
  a 
  single 
  dorsal 
  wart, 
  

   and 
  iii, 
  iv, 
  v 
  and 
  vii 
  are 
  also 
  complicated 
  wart-structures. 
  In 
  the 
  

   Platyptiliids, 
  too, 
  the 
  larvae 
  are 
  characterised 
  by 
  a 
  very 
  general 
  

   clothing 
  of 
  enlarged 
  secondary 
  skin 
  -points 
  or 
  skin-hairs. 
  The 
  simple 
  

   arrangement 
  of 
  the 
  tubercular 
  hairs 
  is 
  of 
  a 
  very 
  generalised 
  character. 
  

   One 
  of 
  the 
  peculiarly 
  Platyptiliid 
  structures 
  is 
  that, 
  on 
  the 
  prothoracic 
  

   plate, 
  the 
  tubercular 
  hairs 
  show 
  three 
  setae 
  along 
  either 
  side 
  of 
  its 
  

   anterior 
  border, 
  whilst 
  behind 
  each 
  half 
  of 
  this 
  row 
  are 
  three 
  other 
  

   setae, 
  not 
  in 
  a 
  row, 
  the 
  internal 
  one 
  being 
  well 
  in 
  front 
  of 
  the 
  posterior 
  

   border 
  of 
  the 
  plate, 
  the 
  middle 
  one, 
  which 
  is 
  the 
  strongest, 
  being 
  

   further 
  back, 
  but 
  nearer 
  the 
  middle 
  line 
  than 
  the 
  middle 
  hair 
  of 
  the 
  

   front 
  row 
  ; 
  the 
  third 
  rather 
  towards 
  the 
  extreme 
  end 
  of 
  the 
  plate 
  

   than 
  part 
  of 
  a 
  posterior 
  row, 
  and 
  being 
  generally 
  the 
  weakest. 
  In 
  

   Capperia 
  (heterodactyla) 
  it 
  looks 
  as 
  if 
  each 
  hair 
  had 
  subdivided 
  and 
  

   formed 
  a 
  little 
  group 
  of 
  hairs 
  without 
  distribution 
  ; 
  it 
  is 
  also 
  to 
  be 
  

   observed 
  that 
  the 
  larva 
  of 
  this 
  species 
  has 
  no 
  central 
  hairs 
  (?) 
  on 
  the 
  pro- 
  

   thorax, 
  thus 
  following 
  the 
  Platyptiliid 
  type 
  ;* 
  also 
  that, 
  in 
  the 
  larva 
  of 
  

   this 
  species, 
  we 
  find 
  the 
  pale 
  central 
  line 
  (characteristic 
  of 
  the 
  Platyp- 
  

   tiliids) 
  that 
  divides 
  the 
  prothoracic 
  plate, 
  all 
  of 
  which 
  characters 
  

   suggest 
  the 
  Oxyptiline 
  connection 
  with 
  the 
  Platyptiliid 
  stirps. 
  Its 
  

   tubercles, 
  however, 
  are 
  modified 
  (as 
  in 
  the 
  Alucitids) 
  into 
  real 
  warts. 
  

   On 
  the 
  other 
  hand, 
  the 
  larva 
  of 
  Capperia 
  has 
  a 
  secondary 
  tubercle 
  

   behind 
  i 
  and 
  ii 
  on 
  the 
  meso- 
  and 
  metathorax, 
  a 
  very 
  unusual 
  

   character 
  in 
  Platyptiliid, 
  and 
  very 
  usual 
  character 
  in 
  Alucitid, 
  larvae. 
  

   In 
  fact, 
  with 
  the 
  exception 
  of 
  a 
  suspicious 
  mark 
  in 
  Stenoptilia 
  ptero- 
  

   dactyla 
  (fitscus) 
  in 
  this 
  position, 
  which, 
  however, 
  carries 
  no 
  hair, 
  it 
  

   appears 
  not 
  to 
  be 
  present 
  in 
  any 
  Platyptiliid 
  larva 
  examined. 
  It 
  may 
  

   be 
  associated 
  with 
  an 
  external-feeding 
  habit 
  (Chapman). 
  

  

  The 
  Platyptiliid 
  pupae 
  are 
  smooth, 
  and 
  more 
  rounded 
  and 
  cylindrical 
  

   than 
  the 
  Alucitine 
  form. 
  It 
  shows 
  a 
  waist 
  if 
  viewed 
  laterally, 
  but 
  

   has 
  the 
  marked 
  ventral 
  curve 
  at 
  the 
  anal 
  end 
  ; 
  in 
  fact, 
  it 
  shows 
  a 
  

   marked 
  tendency 
  in 
  this 
  direction 
  towards 
  the 
  striking 
  Agdistid 
  pupal 
  

  

  * 
  It 
  is 
  remarkable 
  that 
  the 
  larva 
  of 
  Alucita 
  pentadactyla 
  is 
  the 
  only 
  Alucitine 
  

   species 
  of 
  those 
  examined 
  without 
  these 
  central 
  hairs 
  (Chapman). 
  

  

  