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  PROCEEDINGS 
  OF 
  THE 
  FOURTH 
  ENTOMOLOGICAL 
  MEETING 
  

  

  Insectary 
  conditions, 
  however, 
  when 
  one 
  caterpillar 
  was 
  confined 
  with 
  

   several 
  pairs 
  of 
  parasites, 
  it 
  has 
  been 
  found 
  that 
  as 
  many 
  as 
  400-500 
  

   eggs 
  may 
  be 
  laid 
  on 
  one 
  host. 
  But 
  in 
  cases 
  like 
  these 
  the 
  number 
  of 
  

   parasites 
  is 
  so 
  disproportionately 
  large 
  that 
  the 
  caterpillars 
  soon 
  succumb 
  

   to 
  their 
  attack 
  and 
  the 
  grubs 
  consequently 
  die 
  before 
  coming 
  to 
  maturity. 
  

   No 
  such 
  case 
  has 
  been 
  recorded 
  among 
  naturally 
  parasitized 
  caterpillars 
  

   where 
  on 
  account 
  of 
  their 
  small 
  number 
  and 
  consequence 
  abundance 
  of 
  

   food 
  supply 
  they 
  mature 
  and 
  come 
  out 
  to 
  spin 
  cocoons 
  outside 
  the 
  body 
  

   of 
  the 
  host. 
  It 
  has 
  not 
  been 
  possible 
  to 
  determine 
  the 
  exact 
  length 
  of 
  

   the 
  egg 
  stage 
  as 
  the 
  eggs 
  hatch 
  inside 
  the 
  body 
  of 
  the 
  host. 
  It 
  may 
  be 
  

   said 
  here 
  that 
  egg 
  laying 
  is 
  always 
  done 
  on 
  very 
  young 
  host 
  cater- 
  

   pillars 
  during 
  the 
  first 
  and 
  second 
  instars 
  only. 
  

  

  Larva. 
  A 
  full 
  grown 
  larva 
  is 
  5-5 
  mm. 
  long 
  and 
  1-5 
  mm. 
  wide, 
  thickest 
  

   at 
  the 
  middle 
  narrowing 
  to 
  a 
  point 
  at 
  the 
  anterior 
  end 
  and 
  bluntly 
  

   rounded 
  at 
  the 
  posterior 
  where 
  beyond 
  the 
  last 
  abdominal 
  segment 
  there 
  

   is 
  an 
  elongated 
  oval 
  pouch-like 
  appendage 
  about 
  1 
  mm. 
  long 
  with 
  a 
  con- 
  

   striction 
  in 
  between 
  it 
  and 
  the 
  abdomen 
  [Plate 
  XXVII, 
  Fig. 
  2 
  (S)]. 
  

   There 
  are 
  fourteen 
  segments 
  in 
  the 
  body 
  besides 
  the 
  pouch 
  and 
  the 
  

   head 
  is 
  retractile. 
  The 
  colour 
  of 
  a 
  young 
  larva 
  is 
  milky 
  white 
  but 
  as 
  

   it 
  grows 
  the 
  middle 
  portion 
  of 
  the 
  body 
  becomes 
  gradually 
  darker 
  until 
  

   in 
  the 
  full 
  grown 
  stage 
  it 
  becomes 
  very 
  dark 
  with 
  the 
  two 
  sides 
  opaque 
  

   white. 
  Within 
  the 
  body 
  of 
  the 
  host 
  they 
  remain 
  mainly 
  confined 
  in 
  the 
  

   abdominal 
  area 
  and 
  as 
  stated 
  before 
  they 
  never 
  mature 
  if 
  there 
  are 
  too 
  

   many 
  of 
  them 
  within 
  one 
  host. 
  The 
  factors 
  determining 
  the 
  length 
  of 
  

   this 
  stage 
  are 
  temperature 
  and 
  humidity. 
  In 
  December 
  and 
  January 
  the 
  

   length 
  of 
  the 
  egg 
  and 
  larval 
  stages 
  varies 
  from 
  28 
  to 
  34 
  days 
  in 
  January 
  

   and 
  in 
  February 
  it 
  has 
  been 
  found 
  to 
  be 
  25 
  days. 
  But 
  the 
  gradually 
  

   rising 
  temperature 
  in 
  spring 
  exerts 
  its 
  stimulating 
  influence 
  on 
  its 
  vital 
  

   functions 
  and 
  reduces 
  the 
  period 
  to 
  17 
  days 
  in 
  March 
  and 
  still 
  further 
  to 
  

   12 
  days 
  in 
  April. 
  

  

  Pwpa. 
  When 
  a 
  larva 
  matures 
  it 
  punctures 
  the 
  skin 
  of 
  the 
  host 
  and 
  

   gradually 
  makes 
  its 
  way 
  out 
  until 
  the 
  skin 
  round 
  the 
  aperture 
  sits 
  as 
  a 
  

   collar 
  on 
  the 
  constriction 
  between 
  the 
  abdomen 
  and 
  the 
  pouch 
  of 
  the 
  

   emerging 
  larva 
  and 
  it 
  is 
  held 
  firmly 
  in 
  position 
  so 
  as 
  to 
  be 
  able 
  to 
  spin 
  

   its 
  cocoon. 
  Then 
  it 
  commences 
  to 
  spin 
  small 
  loops 
  just 
  in 
  front 
  of 
  the 
  

   head, 
  by 
  moving 
  it 
  in 
  different 
  directions 
  and 
  gradually 
  extends 
  it, 
  over 
  

   the 
  head, 
  backwards 
  and 
  sideways 
  until 
  the 
  anterior 
  half 
  of 
  the 
  body 
  

   is 
  covered 
  with 
  the 
  half 
  formed 
  cocoon 
  [Plate 
  XXVII, 
  Fig. 
  1 
  (4)]. 
  The 
  

   larva 
  then 
  stops 
  spinning 
  and 
  continues 
  to 
  wriggle 
  and 
  twitch 
  its 
  body 
  

   until 
  the 
  pouch 
  is 
  extracted 
  out, 
  which 
  by 
  this 
  time 
  is 
  reduced 
  to 
  half 
  

   its 
  original 
  size. 
  It 
  then 
  turns 
  completely 
  round, 
  i.e., 
  the 
  posterior 
  end 
  

   is 
  thrust 
  into 
  the 
  half-formed 
  cocoon 
  and 
  the 
  head 
  is 
  brought 
  towards 
  

  

  