﻿XV 
  

  

  I 
  have 
  made 
  drawings 
  of 
  the 
  pupa 
  which 
  are 
  reproduced 
  on 
  

   Plate 
  A. 
  It 
  will 
  be 
  seen 
  that 
  there 
  is 
  at 
  the 
  anterior 
  end 
  a 
  

   large 
  more 
  or 
  less 
  roimded 
  mass 
  of 
  somewhat 
  nodular 
  struc- 
  

   ture, 
  from 
  which 
  project 
  two 
  curved 
  and 
  bluntly 
  pointed 
  

   processes 
  suggestive 
  of 
  mandibles. 
  But 
  perhaps 
  the 
  most 
  

   curious 
  development 
  is 
  that 
  of 
  a 
  double 
  ridge 
  of 
  chitin, 
  the 
  

   significance 
  of 
  which 
  is 
  only 
  realised 
  from 
  a 
  frontal 
  view, 
  when 
  

   it 
  is 
  seen 
  to 
  give 
  the 
  appearance 
  of 
  two 
  backwardly 
  directed 
  

   antennae. 
  The 
  extreme 
  " 
  waspishness 
  " 
  of 
  the 
  general 
  effect 
  

   is 
  doubtless 
  much 
  enhanced 
  when 
  the 
  structure 
  is 
  viewed 
  in 
  

   its 
  natural 
  position 
  at 
  the 
  entrance 
  to 
  the 
  burrow. 
  It 
  will 
  be 
  

   observed 
  that 
  the 
  formation 
  is 
  so 
  arranged 
  that 
  when 
  the 
  

   pupa 
  is 
  lying 
  on 
  its 
  dorsal 
  surface 
  the 
  wasp 
  head 
  is 
  in 
  the 
  

   natural 
  position, 
  ?'. 
  e. 
  with 
  the 
  mandibles 
  pointing 
  downwards. 
  

   It 
  would 
  be 
  interesting 
  to 
  know 
  if 
  the 
  pupa 
  always 
  lies 
  in 
  

   this 
  position 
  in 
  the 
  hole. 
  Moreover, 
  the 
  roughened 
  surface 
  

   of 
  the 
  head 
  gives 
  a 
  remarkable 
  resemblance 
  to 
  compound 
  

   eyes. 
  

  

  It 
  may 
  be 
  remarked 
  that 
  since 
  the 
  burrow 
  is 
  plugged 
  with 
  

   silk 
  the 
  wasp-like 
  mask 
  cannot 
  be 
  seen 
  in 
  any 
  case. 
  This 
  is 
  

   true, 
  but 
  it 
  would 
  be 
  of 
  service 
  to 
  the 
  pupa 
  at 
  the 
  critical 
  

   moment 
  between 
  forcing 
  off 
  the 
  silk 
  plug 
  and 
  the 
  emergence 
  

   of 
  the 
  moth. 
  Also 
  many 
  pupae 
  of 
  this 
  habit 
  protrude 
  slightly 
  

   from 
  the 
  burrow 
  for 
  an 
  appreciable 
  period 
  before 
  the 
  imago 
  

   emerges, 
  and 
  this 
  probably 
  happens 
  in 
  the 
  present 
  case. 
  

   It 
  should 
  be 
  noted, 
  however, 
  that 
  a 
  certain 
  wasp 
  makes 
  use 
  

   of 
  the 
  deserted 
  burrows 
  of 
  these 
  and 
  allied 
  wood 
  -boring 
  

   larvae, 
  whilst 
  there 
  is 
  a 
  tree 
  cricket 
  which 
  preys 
  upon 
  the 
  

   pupae, 
  and 
  thus 
  the 
  species 
  is 
  probably 
  protected 
  from 
  the 
  

   cricket 
  by 
  its 
  resemblance 
  to 
  the 
  wasp.' 
  The 
  other 
  allied 
  

   species 
  all 
  have 
  a 
  roughened 
  cap 
  to 
  the 
  pupa, 
  probably 
  used 
  

   in 
  pushing 
  out 
  the 
  silk 
  .plug, 
  but 
  none 
  exhibits 
  even 
  an 
  ap- 
  

   proximation 
  to 
  this 
  wasp-like 
  formation. 
  It 
  is 
  one 
  of 
  those 
  

   structures 
  for 
  which 
  it 
  seems 
  impossible 
  to 
  account 
  on 
  any 
  

   theory 
  of 
  mutation. 
  It 
  is 
  hoped 
  that 
  further 
  observations 
  

   will 
  be 
  made, 
  especially 
  on 
  the 
  habits 
  of 
  the 
  wasps 
  which 
  use 
  

   these 
  burrows, 
  and 
  the 
  predaceous 
  crickets. 
  It 
  should 
  not 
  be 
  

   difficult 
  to 
  discover 
  whether 
  the 
  pupae 
  are 
  in 
  reality 
  protected 
  

   by 
  their 
  disguise. 
  

  

  