﻿BRITISH 
  LEPIDOPTERA. 
  

  

  well 
  up, 
  the 
  better-grown 
  larvae 
  appear 
  to 
  attack 
  the 
  head, 
  but 
  do 
  not 
  

   often 
  seem 
  to 
  eat 
  the 
  heart 
  out 
  of 
  the 
  rising 
  bloom-stalk 
  until 
  

   fullgrown. 
  Sich 
  writes 
  : 
  " 
  On 
  May 
  19th, 
  1904, 
  I 
  found 
  five 
  larvae 
  in 
  

   stems 
  of 
  yarrow, 
  at 
  Chiswick, 
  on 
  a 
  bank 
  close 
  to 
  the 
  river 
  Thames. 
  

   Two 
  of 
  these 
  were 
  in 
  the 
  penultimate 
  instar. 
  One 
  of 
  them, 
  about 
  

   to 
  change 
  its 
  skin, 
  was 
  resting 
  head 
  upwards 
  in 
  the 
  shoot 
  of 
  yarrow 
  

   at 
  the 
  axil 
  of 
  a 
  leaf. 
  The 
  larva 
  chooses 
  this 
  angle 
  (where 
  the 
  leaf 
  

   springs 
  from 
  the 
  stem) 
  to 
  enter 
  the 
  stem 
  ; 
  it 
  does 
  not 
  bore 
  very 
  deeply 
  

   into 
  the 
  stem, 
  preferring 
  to 
  come 
  out 
  and 
  make 
  a 
  fresh 
  hole 
  rather 
  

   than 
  go 
  down 
  to 
  the 
  roots. 
  The 
  interior 
  of 
  the 
  yarrow 
  stem 
  is 
  rather 
  

   soft, 
  and 
  very 
  juicy, 
  where 
  the 
  larva 
  likes 
  to 
  feed. 
  The 
  excrement 
  is 
  

   thrown 
  up 
  in 
  a 
  heap 
  at 
  the 
  entrance 
  of 
  the 
  burrow. 
  In 
  the 
  

   penultimate 
  instar, 
  the 
  larva 
  has 
  dark 
  purplish-brown 
  stripes, 
  which 
  

   harmonise 
  very 
  well 
  with 
  the 
  similarly 
  coloured 
  young 
  stems 
  of 
  the 
  

   yarrow. 
  The 
  youugest 
  shoots 
  of 
  the 
  yarrow 
  are 
  green, 
  but 
  they 
  are 
  

   often 
  ornamented, 
  when 
  older, 
  with 
  deep 
  red-brown 
  lines. 
  In 
  the 
  final 
  

   instar, 
  the 
  larva 
  loses 
  all 
  the 
  purple 
  colour, 
  being 
  at 
  first 
  of 
  a 
  

   somewhat 
  olive 
  tint, 
  but, 
  as 
  it 
  approaches 
  maturity, 
  it 
  becomes 
  paler 
  

   and 
  clearer 
  green, 
  and 
  has 
  a 
  less 
  solid 
  appearance. 
  One 
  was 
  fullgrown 
  

   on 
  May 
  21st, 
  and 
  another 
  produced 
  a 
  parasite 
  on 
  the 
  same 
  day 
  ; 
  the 
  

   last 
  of 
  the 
  larvae 
  spun 
  up 
  June 
  9th." 
  Barrett 
  says 
  the 
  larvae 
  feed 
  in 
  

   shoots 
  of 
  yarrow, 
  apparently 
  preferring 
  the 
  central 
  shoot, 
  and 
  eating 
  

   downwards 
  towards 
  the 
  root, 
  and 
  Porritt 
  adds 
  that, 
  when 
  fullgrown, 
  the 
  

   larva 
  leaves 
  the 
  shoot 
  for 
  pupation. 
  The 
  larva 
  of 
  G. 
  pallid 
  actyla, 
  he 
  says, 
  is 
  

   rather 
  an 
  external 
  than 
  an 
  internal 
  feeder, 
  and 
  its 
  habits 
  vary 
  much 
  from 
  

   those 
  of 
  G.ochrodactyla; 
  it 
  feeds 
  on 
  Achillea 
  millefolium 
  and 
  A. 
  ptarmica, 
  

   attacking 
  the 
  top 
  of 
  a 
  young 
  shoot, 
  eating 
  out 
  the 
  heart 
  and 
  feeding 
  

   downwards 
  for 
  a 
  short 
  distance 
  into 
  the 
  tender 
  young 
  stem, 
  then 
  leaves 
  

   it 
  to 
  attack 
  another 
  young 
  shoot 
  in 
  the 
  same 
  manner. 
  Larvae 
  were 
  to 
  

   be 
  found 
  at 
  Higham 
  until 
  May 
  26th, 
  1904, 
  when 
  most 
  were 
  fullfed 
  

   (Ovenden) 
  ; 
  larvae 
  found 
  fullfed 
  on 
  June 
  6th, 
  1900, 
  pupated 
  from 
  

   June 
  12th, 
  at 
  Hazeleigh 
  (Raynor) 
  ; 
  larvae 
  of 
  various 
  sizes 
  from 
  Tilly 
  - 
  

   coultry, 
  June 
  25th, 
  1885, 
  fed 
  up 
  and 
  pupated 
  in 
  due 
  course, 
  the 
  first 
  

   moth 
  not 
  emerging 
  until 
  July 
  24th, 
  1885 
  (Porritt). 
  Kaltenbach, 
  who 
  

   first 
  discovered 
  the 
  larvae 
  on 
  the 
  Continent, 
  found 
  them 
  on 
  May 
  15th, 
  

   1857, 
  on 
  Achillea 
  ptarmica, 
  at 
  Aachen 
  (Aix), 
  living 
  solitarily 
  at 
  first, 
  

   between 
  the 
  united 
  top 
  leaves, 
  but 
  later 
  boring 
  into 
  the 
  stem, 
  the 
  delicate 
  

   pink 
  pith 
  of 
  which 
  they 
  eat 
  out 
  to 
  the 
  depth 
  of 
  an 
  inch, 
  the 
  presence 
  of 
  

   the 
  larva 
  being 
  very 
  apparent 
  from 
  the 
  black 
  mass 
  of 
  frass 
  which 
  

   it 
  turns 
  out 
  from 
  an 
  especially-made 
  ejection 
  opening 
  (Pflanzenfeinde, 
  

   pp. 
  347-8). 
  

  

  Larva. 
  — 
  First 
  instar 
  (somewhat 
  grown, 
  July 
  21st, 
  1904) 
  : 
  Rather 
  

   short, 
  thick-set, 
  with 
  round, 
  black, 
  polished 
  head, 
  paler 
  brownish 
  

   scutellum 
  and 
  anal 
  plates. 
  Body 
  pale 
  yellow, 
  of 
  even 
  thickness, 
  the 
  

   skin 
  smooth 
  and 
  shiny 
  with 
  a 
  peculiar 
  yellow 
  spotting, 
  as 
  if 
  it 
  had 
  

   little 
  globules 
  of 
  fat 
  beneath 
  it. 
  No 
  spicules 
  visible 
  with 
  an 
  1-inch 
  

   objective, 
  hairs 
  tapering; 
  the 
  incisions 
  of 
  segments 
  clear 
  and 
  sharp; 
  

   spiracles 
  somewhat 
  raised; 
  the 
  position 
  of 
  the 
  tubercles 
  seems 
  quite 
  

   normal 
  for 
  the 
  group 
  ; 
  on 
  the 
  meso- 
  and 
  metathorax 
  i 
  and 
  ii 
  are 
  near 
  

   together, 
  i 
  slightly 
  in 
  front 
  and 
  inside 
  ii 
  ; 
  iii 
  and 
  iv 
  close 
  together, 
  v 
  

   alone, 
  in 
  usual 
  position 
  below. 
  The 
  hairs 
  of 
  the 
  same 
  colour 
  as 
  the 
  

   body, 
  very 
  indistinct. 
  The 
  positions 
  of 
  the 
  tubercles 
  on 
  the 
  abdominal 
  

   segments 
  appear 
  to 
  be 
  as 
  usual 
  (but 
  the 
  light 
  is 
  not 
  good 
  enough 
  for 
  

  

  