﻿LIFE-HISTORY 
  OF 
  AUSTRALIAN 
  MOTH-LACEWING, 
  ITHONE 
  FUSCA, 
  NEWMAN. 
  215 
  

  

  delta, 
  epsilon 
  and 
  rho. 
  I 
  have 
  used 
  the 
  condition 
  of 
  this 
  pinaculum 
  as 
  a 
  convenient 
  

   diagnostic 
  character 
  for 
  determining 
  the 
  first 
  three 
  instars, 
  as 
  may 
  be 
  seen 
  from 
  text- 
  

   figs. 
  5-7. 
  Below 
  the 
  dotted 
  line 
  microtrichia 
  are 
  very 
  weakly 
  developed 
  for 
  a 
  space, 
  

   this 
  area 
  always 
  including 
  pi 
  ; 
  but, 
  lower 
  down, 
  they 
  again 
  come 
  more 
  into 
  evidence. 
  

  

  Fig 
  

  

  Ithone 
  fusca, 
  Xevvm., 
  first 
  larval 
  instar 
  ; 
  diagram 
  of 
  

   chaetotaxy 
  of 
  metathorax 
  (Th 
  3 
  ) 
  and 
  first 
  two 
  abdominal 
  

   segments 
  (Abj, 
  Ab 
  2 
  ), 
  to 
  show 
  positions 
  of 
  primary 
  setae, 
  

   with 
  Fracker's 
  notation 
  ; 
  P 
  3> 
  coxa 
  of 
  hind 
  leg. 
  

  

  Secondary 
  setae 
  of 
  the 
  type 
  which 
  appears 
  on 
  the 
  metathorax 
  in 
  the 
  second 
  instar 
  

   are 
  already 
  present 
  on 
  the 
  anal 
  papilla 
  at 
  the 
  first 
  instar, 
  and 
  the 
  end 
  of 
  the 
  abdomen 
  

   is 
  conspicuously 
  more 
  hairy 
  than 
  the 
  rest 
  of 
  it 
  ; 
  so 
  that 
  we 
  are 
  justified 
  in 
  considering 
  

   segment 
  10 
  as 
  already 
  specialised 
  in 
  this 
  larva. 
  

  

  During 
  the 
  first 
  instar, 
  the 
  larvae 
  grow 
  considerably, 
  the 
  prothorax 
  and 
  back 
  of 
  

   the 
  head 
  swelling 
  out 
  with 
  the 
  other 
  segments. 
  But 
  this 
  instar 
  can 
  always 
  be 
  recog- 
  

   nised 
  by 
  the 
  comparatively 
  large 
  size 
  of 
  the 
  head, 
  the 
  small, 
  circular 
  spiracles, 
  and 
  

   the 
  presence 
  of 
  the 
  primary 
  setae 
  only 
  on 
  the 
  thorax 
  and 
  first 
  eight 
  abdominal 
  segments. 
  

  

  Second 
  Larval 
  Instar 
  (Plate 
  iv, 
  fig. 
  3 
  

  

  text-fig. 
  

  

  6). 
  

  

  The 
  second 
  larval 
  instar 
  superficially 
  resembles 
  the 
  first, 
  except 
  for 
  its 
  larger 
  size 
  

   and 
  the 
  comparatively 
  smaller 
  size 
  of 
  the 
  head 
  in 
  relation 
  to 
  the 
  prothorax. 
  

   The 
  head 
  is 
  more 
  swollen 
  below 
  the 
  bases 
  of 
  the 
  maxillae, 
  and 
  there 
  is 
  a 
  distinct 
  

   beginning 
  of 
  the 
  tendencv, 
  so 
  noticeable 
  in 
  the 
  later 
  instars, 
  for 
  the 
  mouth-parts 
  

   to 
  turn 
  upwards. 
  The 
  labial 
  palps 
  are 
  definitely 
  five-segmented. 
  The 
  three 
  pairs 
  of 
  

   legs 
  are 
  more 
  nearly 
  equal 
  in 
  size 
  than 
  in 
  the 
  first 
  instar. 
  The 
  spiracles 
  are 
  greatly 
  

   enlarged, 
  and 
  of 
  a 
  broad 
  oval 
  shape, 
  with 
  the 
  aperture 
  in 
  the 
  form 
  of 
  a 
  wide 
  slit 
  ; 
  

  

  (6750) 
  

  

  p2 
  

  

  