﻿LIFE-HISTORY 
  OF 
  AUSTRALIAN 
  MOTH-LACEWTNG, 
  ITHONE 
  FUSCA, 
  NEWMAN. 
  213 
  

  

  fused 
  together. 
  It 
  is 
  shaped 
  rather 
  like 
  an 
  elongated 
  tooth, 
  the 
  outer 
  edge 
  being 
  

   curved, 
  the 
  inner 
  straight. 
  The 
  extreme 
  tip 
  is 
  notched, 
  forming 
  the 
  entrance 
  to 
  a 
  

   deep 
  groove, 
  which 
  can 
  be 
  traced 
  with 
  ease 
  along 
  most 
  of 
  its 
  length. 
  On 
  the 
  outer 
  

   edge, 
  near 
  the 
  base, 
  three 
  strong 
  setae 
  are 
  developed. 
  The 
  labium 
  (text-fig. 
  4) 
  

   consists 
  of 
  a 
  pair 
  of 
  four-segmented 
  palpi 
  with 
  their 
  bases 
  set 
  closely 
  together 
  on 
  the 
  

  

  Fig. 
  4. 
  Ithone 
  fusca, 
  Newm., 
  first 
  

   larval 
  instar, 
  labium 
  ( 
  x 
  208). 
  

  

  underside 
  of 
  the 
  head, 
  below 
  and 
  between 
  the 
  two 
  maxillae 
  ; 
  there 
  is 
  no 
  separate 
  

   basal 
  piece 
  visible. 
  The 
  1st 
  segment 
  is 
  about 
  as 
  long 
  as 
  wide, 
  the 
  2nd 
  a 
  little 
  narrower, 
  

   only 
  slightly 
  more 
  than 
  half 
  as 
  long 
  as 
  wide, 
  the 
  3rd 
  very 
  slightly 
  narrower 
  still, 
  as 
  

   long 
  as 
  wide, 
  and 
  with 
  its 
  basal 
  3rd 
  just 
  slightly 
  constricted 
  off 
  from 
  the 
  rest 
  by 
  a 
  

   faint 
  suture 
  ; 
  this 
  suture 
  indicates 
  the 
  line 
  along 
  which 
  this 
  segment 
  divides 
  into 
  

   two 
  at 
  the 
  next 
  instar, 
  when 
  the 
  palpi 
  become 
  definitely 
  five-segmented. 
  The 
  4th 
  or 
  

   terminal 
  segment 
  is 
  somewhat 
  acorn-shaped, 
  nearly 
  twice 
  as 
  long 
  as 
  broad, 
  and 
  

   longer 
  than 
  the 
  basal 
  segment 
  ; 
  at 
  its 
  apex 
  it 
  carried 
  a 
  set 
  of 
  five 
  small 
  sensory 
  

   organs 
  in 
  the 
  form 
  of 
  short, 
  stiff, 
  cylindrical 
  chitinous 
  projections. 
  Large 
  tactile 
  

   setae 
  are 
  situated 
  as 
  shown 
  in 
  text-fig. 
  4. 
  

  

  Thorax 
  : 
  Prothorax 
  about 
  as 
  long 
  as 
  head, 
  but 
  broader, 
  with 
  a 
  large 
  shield-like 
  

   pronotum, 
  quite 
  smooth 
  and 
  devoid 
  of 
  microtrichia, 
  but 
  carrying 
  10 
  primary 
  setae 
  

   on 
  either 
  side, 
  as 
  shown 
  in 
  text-fig. 
  2. 
  A 
  conspicuous 
  spiracle, 
  the 
  only 
  one 
  present 
  

   on 
  the 
  thorax, 
  is 
  to 
  be 
  seen 
  rather 
  low 
  down 
  at 
  the 
  back 
  of 
  the 
  prothorax 
  on 
  either 
  

   side, 
  in 
  the 
  softer 
  portion 
  lying 
  just 
  in 
  front 
  of 
  the 
  mesothorax 
  ; 
  it 
  is 
  circular, 
  with 
  

   a 
  small 
  central 
  aperture, 
  and 
  measures 
  about 
  0-03 
  mm. 
  in 
  diameter. 
  Meso- 
  and 
  

   metathorax 
  about 
  equal, 
  each 
  shorter 
  than 
  the 
  prothorax, 
  but 
  of 
  about 
  the 
  same 
  

   breadth 
  ; 
  primary 
  setae 
  as 
  shown 
  in 
  text-fig. 
  2. 
  Each 
  of 
  these 
  segments 
  shows 
  

   signs 
  of 
  a 
  transverse 
  division 
  on 
  the 
  notum 
  by 
  a 
  slightly 
  impressed 
  line 
  at 
  about 
  

   two-fifths 
  of 
  the 
  segments' 
  length 
  from 
  the 
  anterior 
  border, 
  similar 
  to 
  that 
  shown 
  

   in 
  abdominal 
  segments 
  1-7. 
  Legs 
  very 
  strongly 
  formed, 
  of 
  burrowing 
  type, 
  with 
  

   large 
  coxae, 
  stout, 
  somewhat 
  curved, 
  forwardly 
  projecting 
  femora, 
  and 
  short 
  tibio- 
  

   tarsi 
  carrying 
  large 
  digging-claws 
  curved 
  backwards. 
  The 
  forelegs 
  are 
  the 
  largest 
  

   and 
  possess 
  the 
  strongest 
  claws 
  ; 
  the 
  middle 
  legs 
  are 
  considerably 
  shorter, 
  the 
  hind- 
  

   legs 
  slightly 
  smaller 
  than 
  the 
  middle 
  ones. 
  The 
  coxae 
  of 
  the 
  forelegs 
  are 
  inserted 
  

   fairly 
  close 
  together, 
  those 
  of 
  the 
  other 
  two 
  pairs 
  much 
  further 
  apart. 
  

  

  Abdomen 
  greatly 
  curved, 
  broadest 
  at 
  base, 
  tapering 
  gradually 
  towards 
  apex. 
  

   First 
  eight 
  segments 
  clearly 
  marked, 
  each 
  with 
  its 
  pair 
  of 
  small 
  circular 
  spiracles, 
  

   of 
  which 
  the 
  first 
  seven 
  are 
  only 
  about 
  half 
  as 
  large 
  as 
  the 
  prothoracic, 
  the 
  Sth 
  a 
  

  

  (6750) 
  p 
  

  

  