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  BRITISH 
  LEPIDOPTEEA. 
  

  

  in 
  Eucnemidophorus, 
  fairly-developed, 
  and 
  carrying 
  strongly-developed 
  

   halbert-like 
  processes, 
  in 
  Amblyptilia 
  and 
  Marasmarcha). 
  In 
  the 
  

   imaginal 
  characters, 
  the 
  genera 
  Eucnemidophorus 
  and 
  Amblyptilia 
  

   present 
  all 
  the 
  naked-eye 
  appearances 
  of 
  the 
  Platyptiliines, 
  particularly 
  

   in 
  the 
  shape 
  of 
  the 
  fore 
  wing 
  and 
  the 
  dark 
  scale- 
  tuft 
  on 
  the 
  3rd 
  plumule 
  

   of 
  the 
  hindwings, 
  whilst, 
  in 
  these 
  respects, 
  Marasmarcha 
  has 
  undergone 
  

   considerable 
  variation 
  in 
  the 
  direction 
  of 
  the 
  Oxyptilines. 
  

  

  The 
  pupae 
  of 
  Marasmarcha 
  (liinaedactyla) 
  and 
  Amblyptilia 
  (cosmodac- 
  

   tyla) 
  appear 
  to 
  be 
  very 
  similar, 
  inasmuch 
  as 
  they 
  show 
  a 
  marked 
  develop- 
  

   ment 
  of 
  the 
  dorsal 
  ridge, 
  but 
  Bacot 
  says 
  that 
  these 
  processes, 
  carrying 
  

   the 
  tubercles, 
  are 
  really 
  different 
  structurally, 
  and 
  have 
  probably 
  

   reached 
  their 
  present 
  state 
  of 
  perfection, 
  independently, 
  from 
  a 
  primi- 
  

   tive 
  common 
  ground 
  ; 
  this 
  is 
  particularly 
  evidenced 
  by 
  the 
  differences 
  

   in 
  the 
  character 
  of 
  the 
  processes, 
  on 
  the 
  segments 
  following 
  the 
  3rd 
  

   abdominal, 
  being 
  quite 
  as 
  marked 
  as 
  in 
  the 
  more 
  highly-developed 
  

   ones. 
  Chapman 
  observes 
  that 
  the 
  essential 
  structural 
  difference 
  

   between 
  the 
  pupae 
  of 
  the 
  two 
  genera 
  is 
  that, 
  in 
  that 
  of 
  Marasmarcha, 
  

   there 
  is 
  an 
  inner 
  posterior 
  set 
  of 
  humps 
  like 
  those 
  of 
  some 
  Oxyptilid 
  

   pupae. 
  He 
  tbinks 
  that 
  the 
  pupal 
  armature 
  of 
  these 
  may 
  have 
  arisen 
  

   in 
  common, 
  whilst 
  that 
  of 
  Amblyptilia 
  may 
  be 
  an 
  earlier 
  stage 
  of 
  the 
  

   same 
  development 
  (branching 
  off 
  a 
  little 
  in 
  another 
  direction), 
  but 
  is 
  

   more 
  probably 
  a 
  separate, 
  though 
  similar, 
  development. 
  Bacot 
  

   further 
  adds 
  that 
  the 
  pupa 
  of 
  Amblyptilia 
  is 
  nearer 
  the 
  Stenoptiliines 
  

   in 
  slenderness 
  and 
  shape, 
  whilst 
  that 
  of 
  Marasmarcha 
  is 
  less 
  slender, 
  

   and 
  has 
  a 
  less 
  marked 
  dorsal 
  band, 
  inclining 
  rather 
  to 
  the 
  Oxyptilid 
  

   form. 
  

  

  As 
  to 
  the 
  differences 
  in 
  the 
  larval 
  characters, 
  Bacot 
  observes 
  that 
  the 
  

   larvae 
  appear 
  to 
  show 
  greater 
  divergences 
  than 
  the 
  pupae, 
  the 
  secondary 
  

   skin-hairs 
  in 
  Marasmarcha 
  being 
  few 
  in 
  number 
  compared 
  with 
  those 
  

   in 
  Amblyptilia, 
  although 
  both 
  vary 
  much, 
  whilst 
  the 
  depressed 
  scutellar 
  

   spots 
  are 
  not 
  pigmented 
  in 
  the 
  former 
  as 
  in 
  the 
  latter, 
  that 
  of 
  Amblyptilia 
  

   falling 
  in 
  closely, 
  in 
  this 
  respect, 
  with 
  the 
  Stenoptiliines, 
  Marasmarcha, 
  

   on 
  the 
  other 
  hand, 
  being 
  apparently 
  rather 
  more 
  distant 
  therefrom. 
  The 
  

   amount 
  of 
  wart-development 
  places 
  A 
  mblyptilia 
  rather 
  nearer 
  the 
  Adkinia 
  

   species 
  (bipunctidactyla 
  and 
  zophodactylus) 
  , 
  whilst 
  that 
  of 
  Marasmarcha 
  

   runs 
  nearer 
  that 
  of 
  Stenoptilia 
  (pterodactyla) 
  , 
  possibly 
  due 
  to 
  a 
  parallelism 
  

   in 
  the 
  larval 
  habits 
  as 
  exhibited 
  in 
  the 
  amount 
  of 
  external-feeding. 
  

   Chapman 
  says 
  that 
  too 
  much 
  stress 
  must 
  not 
  be 
  placed 
  on 
  the 
  number 
  

   of 
  secondary 
  hairs 
  met 
  with 
  in 
  the 
  larvae 
  of 
  Marasmarcha, 
  because 
  

   some 
  have 
  hardly 
  any, 
  whilst 
  others 
  have 
  quite 
  as 
  many 
  as 
  the 
  larvae 
  

   of 
  Amblyptilia. 
  

  

  We 
  have 
  above 
  referred 
  to 
  the 
  pupal 
  dorsal 
  ridge 
  (or 
  ridges). 
  

   These 
  are 
  peculiar 
  structures, 
  found 
  only 
  in 
  the 
  Platyptiliidae, 
  double 
  

   in 
  character, 
  inasmuch 
  as 
  there 
  is 
  one 
  on 
  either 
  side 
  of 
  the 
  dorsal 
  

   line, 
  arising 
  on 
  the 
  prothorax, 
  and 
  passing 
  backwards 
  as 
  far 
  as 
  

   tubercle 
  ii 
  on 
  the 
  3rd 
  abdominal 
  segment, 
  and 
  then 
  abruptly 
  ceasing. 
  

   They 
  approach 
  the 
  middle 
  line 
  most 
  nearly 
  at 
  the 
  posterior 
  border 
  of 
  

   the 
  mesothorax, 
  and 
  are, 
  perhaps, 
  best 
  seen 
  in 
  the 
  genus 
  Gillmeria; 
  

   they 
  are 
  almost 
  evanescent 
  on 
  the 
  abdominal 
  segments 
  of 
  Platyptilia 
  

   isodactylus, 
  especially 
  of 
  the 
  summer 
  brood. 
  In 
  Marasmarcha 
  liinae- 
  

   dactyla, 
  and 
  the 
  Amblyptiliae, 
  they 
  terminate 
  in 
  the 
  great 
  halbert- 
  

   shaped 
  processes 
  of 
  the 
  3rd 
  abdominal 
  segment, 
  as 
  in 
  the 
  other 
  

   groups, 
  the 
  similar 
  processes 
  on 
  the 
  following 
  segments 
  being 
  isolated, 
  

  

  