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  BRITISH 
  LEPIDOPTERA. 
  

  

  ridge 
  formed 
  by 
  the 
  hairs 
  along 
  the 
  wing-costa, 
  and 
  the 
  fan-hairs 
  of 
  

   iv 
  and 
  v 
  are 
  modified 
  into 
  a 
  similar 
  fan 
  development. 
  It 
  is 
  remarkable 
  

   that 
  the 
  pupa 
  of 
  Porrittia 
  galactodaetyla 
  is 
  of 
  the 
  same 
  type 
  as 
  that 
  

   of 
  Oidaematopkorus 
  lithodactyla, 
  the 
  only 
  differences 
  being 
  that 
  the 
  dorsal 
  

   tubercles 
  are 
  more 
  distinct, 
  and 
  the 
  hairs 
  arising 
  therefrom 
  not 
  so 
  

   definitely 
  in 
  a 
  vertical 
  plane, 
  and, 
  therefore, 
  form 
  less 
  distinctly 
  the 
  

   fan 
  pattern 
  ; 
  the 
  lateral 
  (subspiracular, 
  formed 
  of 
  iv 
  and 
  v) 
  fan-ridge 
  

   is, 
  however, 
  equally 
  well-developed 
  with 
  that 
  of 
  0. 
  lithodactyla, 
  the 
  

   wing-edge 
  having 
  also 
  a 
  strong 
  row 
  of 
  hairs. 
  The 
  pupa 
  of 
  Wheeleria 
  

   megadactyla 
  (spilodactyla) 
  has 
  no 
  dorsal 
  or 
  lateral 
  flanges, 
  but 
  there 
  

   are 
  many 
  secondary 
  hairs, 
  especially 
  along 
  the 
  hind 
  margin 
  of 
  the 
  

   segments, 
  forming 
  a 
  ridge 
  ; 
  tubercle 
  i 
  has 
  two 
  hairs 
  (except 
  on 
  the 
  

   2nd 
  and 
  3rd 
  abdominal 
  segments 
  where 
  it 
  is 
  large 
  and 
  carries 
  several 
  

   strong 
  hairs) 
  ; 
  ii 
  is 
  single-haired 
  ; 
  iii 
  has 
  two 
  large 
  and 
  other 
  smaller 
  

   hairs, 
  whilst 
  iv+v 
  forms 
  one 
  circular 
  boss 
  of 
  hairs 
  ; 
  hairs 
  are 
  also 
  found 
  

   on 
  the 
  wings, 
  antenna? 
  and 
  legs. 
  The 
  pupa 
  of 
  Alucita 
  pentadactyla 
  

   is 
  a 
  hairy 
  one, 
  but 
  of 
  an 
  entirely 
  different 
  type 
  from 
  that 
  of 
  0. 
  litho- 
  

   dactyla 
  ; 
  the 
  tubercles 
  have 
  the 
  hairs 
  disposed 
  in 
  all 
  directions 
  and 
  

   not 
  fanwise, 
  and 
  iii 
  is 
  an 
  important 
  tubercle. 
  The 
  wings 
  and 
  antenna? 
  

   have 
  several 
  rows 
  of 
  hairs, 
  and, 
  except 
  the 
  wing-row 
  of 
  hairs, 
  there 
  is 
  

   no 
  tendency 
  to 
  the 
  formation 
  of 
  a 
  lateral 
  ridge 
  or 
  flange. 
  

  

  As 
  to 
  the 
  evolution 
  of 
  the 
  Alucitid 
  pupa, 
  Chapman 
  notes 
  {antea, 
  

   ii., 
  p. 
  96) 
  that 
  the 
  Alucitids 
  are 
  very 
  exceptional 
  in 
  their 
  pupae. 
  As 
  

   we 
  have 
  noted, 
  they 
  rarely 
  have 
  a 
  cocoon 
  from 
  which 
  to 
  emerge, 
  and 
  

   attach 
  themselves 
  by 
  cremastral 
  hooks 
  to 
  a 
  silken 
  pad 
  that 
  is 
  paralleled 
  

   only 
  in 
  a 
  family 
  with 
  obtect 
  pupa?, 
  viz., 
  that 
  consisting 
  of 
  Hypercallia, 
  

   Anchinia, 
  and 
  their 
  allies. 
  They 
  have 
  preserved 
  three 
  free 
  segments, 
  

   either 
  because 
  they 
  have 
  never 
  had 
  occasion 
  to 
  lose 
  them, 
  but 
  more 
  

   probably 
  because 
  it 
  enables 
  them 
  to 
  make 
  that 
  remarkable 
  somersault 
  

   movement 
  backwards, 
  a 
  movement 
  no 
  doubt 
  useful 
  in 
  repelling 
  

   or 
  frightening 
  enemies. 
  They, 
  as 
  well 
  as 
  the 
  Hypercallias, 
  have 
  

   cremastral 
  hooks 
  on 
  the 
  8th 
  abdominal 
  segment, 
  as 
  well 
  as 
  the 
  usual 
  

   10th, 
  giving 
  an 
  extended 
  and 
  solid 
  hold 
  of 
  the 
  silken 
  pad, 
  and 
  affording 
  

   a 
  special 
  means 
  of 
  meeting 
  the 
  difficulties 
  of 
  the 
  pupal 
  moult. 
  The 
  

   Agdistid 
  pupa? 
  are 
  typically 
  Alucitid 
  in 
  the 
  head 
  sculpturing, 
  in 
  the 
  

   free 
  segmentation, 
  in 
  the 
  method 
  of 
  attachment, 
  and 
  in 
  dehiscence 
  

   (the 
  dorsal 
  headpiece 
  carrying 
  the 
  eyes, 
  etc.) 
  ; 
  they 
  differ, 
  however, 
  in 
  

   being 
  smooth 
  and 
  very 
  elongated. 
  The 
  Alucitid 
  pupa?, 
  on 
  the 
  other 
  

   hand, 
  appear 
  always 
  to 
  be 
  short, 
  very 
  blunt 
  forward, 
  and 
  often 
  to 
  be 
  

   rough. 
  There 
  is 
  a 
  strong 
  tendency 
  to 
  a 
  longitudinal 
  subdorsal 
  ridge 
  

   in 
  the 
  line 
  of 
  the 
  trapezoidal 
  tubercles, 
  and 
  this 
  carries 
  either 
  bundles 
  

   of 
  hairs, 
  or 
  great 
  horns 
  of 
  pupal 
  tissue, 
  the 
  former 
  being 
  more 
  common 
  

   in 
  those 
  species 
  with 
  hairy 
  larva?, 
  the 
  disposition 
  of 
  the 
  hairs 
  on 
  the 
  

   larva? 
  and 
  pupa? 
  being 
  much 
  alike, 
  the 
  horned 
  pupa? 
  being 
  more 
  

   common 
  in 
  those 
  species 
  whose 
  larva? 
  have 
  simple 
  tubercles. 
  The 
  

   pupa 
  is 
  usually 
  fully 
  exposed 
  and 
  generally 
  fixed 
  with 
  its 
  head 
  down- 
  

   wards, 
  although, 
  in 
  some 
  species, 
  it 
  is 
  enclosed 
  in 
  a 
  puparium, 
  e.g., 
  

   Platyptilia 
  yonodactyla, 
  whilst 
  the 
  pupa? 
  of 
  both 
  broods 
  of 
  P. 
  uodactyla, 
  

   and 
  the 
  summer 
  brood 
  of 
  Adaina 
  microdactyla, 
  lie 
  free 
  in 
  the 
  hollow 
  made 
  

   at 
  the 
  end 
  of 
  the 
  tunnels 
  in 
  which 
  they 
  have 
  been 
  feeding. 
  Chapman 
  

   further 
  adds 
  {in 
  lift.) 
  that 
  the 
  important 
  point 
  that 
  the 
  pupal 
  structure 
  

   brings 
  out, 
  as 
  regards 
  the 
  position 
  of 
  the 
  family, 
  is 
  that 
  the 
  allies 
  of 
  

   the 
  Alucitids 
  are 
  to 
  be 
  found 
  among 
  those 
  with 
  similar 
  incomplete 
  

  

  