﻿112 
  

  

  resolved 
  to 
  try 
  one 
  more. 
  At 
  ttat 
  one 
  I 
  found 
  forty-six 
  pupae 
  of 
  Ennoraos 
  illunaria, 
  

   and 
  three 
  of 
  Pcecilocampa 
  Populi 
  ! 
  

  

  " 
  No 
  pupa-hunler 
  can 
  hope 
  for 
  success, 
  unless 
  he 
  have 
  a 
  good 
  stock 
  of 
  patience 
  

   and 
  perseverance. 
  He 
  must 
  not 
  mind 
  cold 
  hands, 
  wet 
  feet, 
  or 
  an 
  aching 
  back 
  ; 
  for 
  

   although 
  these 
  are 
  drawbacks, 
  yet 
  is 
  the 
  pursuit 
  (to 
  me) 
  quite 
  exciting, 
  when 
  success- 
  

   ful, 
  and 
  it 
  will 
  reward 
  the 
  seeker, 
  not 
  merely 
  of 
  Lepidoptera, 
  but 
  also 
  of 
  all 
  the 
  other 
  

   orders 
  of 
  insects. 
  

  

  "The 
  longer 
  I 
  continue 
  to 
  dig 
  for 
  pups, 
  the 
  more 
  convinced 
  T 
  am 
  that 
  one 
  of 
  the 
  

   causes 
  of 
  the 
  periodical 
  uncertainty 
  in 
  the 
  appearance 
  of 
  many 
  insects 
  is 
  their 
  inabili- 
  

   ty, 
  under 
  certain 
  circumstances, 
  to 
  force 
  their 
  way 
  through 
  the 
  earth. 
  As 
  I 
  have 
  re- 
  

   marked, 
  on 
  a 
  former 
  occasion, 
  severe 
  frost 
  following 
  protracted 
  rain 
  will 
  have 
  this 
  ef- 
  

   fect, 
  as 
  also 
  will 
  great 
  heat. 
  I 
  once 
  had 
  a 
  singular 
  illustration 
  of 
  this. 
  Digging 
  at 
  

   the 
  roots 
  of 
  an 
  elm, 
  I 
  turned 
  up 
  a 
  large 
  lump 
  of 
  baked 
  clay. 
  On 
  breaking 
  it, 
  I 
  found 
  

   no 
  fewer 
  than 
  sixteen 
  pupae 
  of 
  Taeniocampa 
  instabilis 
  imbedded 
  in 
  it 
  : 
  the 
  shells 
  were 
  

   quite 
  brittle, 
  and 
  on 
  opening 
  them 
  I 
  found 
  the 
  insect 
  perfectly 
  developed, 
  but 
  dead. 
  

   Another 
  cause 
  which 
  tends 
  to 
  make 
  insects 
  scarce 
  or 
  uncertain 
  in 
  their 
  appearance, 
  is, 
  

   of 
  course, 
  the 
  Ichneumon, 
  that 
  foe 
  to 
  the 
  entomologist. 
  The 
  havoc 
  committed 
  by 
  them 
  

   would 
  appear 
  incredible 
  to 
  those 
  who 
  have 
  not 
  witnessed 
  their 
  destructive 
  powers 
  as 
  I 
  

   have, 
  while 
  digging 
  for 
  piipoe. 
  Take, 
  for 
  example, 
  Lithosia 
  rubricollis. 
  At 
  Guiting 
  

   I 
  found 
  the 
  pupae 
  of 
  this 
  insect 
  by 
  hundreds. 
  It 
  is 
  no 
  exaggeration 
  to 
  say 
  that 
  three- 
  

   fifths 
  at 
  least 
  of 
  these 
  had 
  been 
  destroyed 
  by 
  Ichneumons, 
  Their 
  empty 
  pupa-cases, 
  

   with 
  the 
  circular 
  opening 
  always 
  made 
  by 
  the 
  Ichneumon, 
  lay 
  scattered 
  about 
  by 
  do- 
  

   zens 
  ; 
  and 
  I 
  have 
  repeatedly 
  liberated 
  the 
  parasite 
  itself 
  in 
  turning 
  up 
  the 
  sod. 
  

  

  " 
  It 
  may 
  be 
  asked 
  — 
  ' 
  How 
  do 
  you 
  know 
  the 
  species 
  of 
  those 
  pupae 
  which 
  are 
  as 
  yet 
  

   undisclosed 
  ?' 
  To 
  this 
  I 
  would 
  answer, 
  chiefly 
  by 
  experience. 
  As 
  a 
  general 
  princi- 
  

   ple, 
  it 
  is 
  not 
  difficult 
  to 
  decide 
  to 
  what 
  fomily 
  a 
  pupa 
  belongs. 
  A 
  Bombyx 
  may 
  some- 
  

   times 
  be 
  known 
  at 
  once 
  by 
  its 
  form, 
  which 
  nevertheless 
  varies 
  considerably. 
  More- 
  

   over, 
  all 
  Bombyces 
  form 
  a 
  web 
  or 
  cocoon, 
  at 
  least 
  all 
  those 
  with 
  which 
  I 
  am 
  acquainted 
  

   in 
  the 
  pupa 
  slate. 
  This, 
  however, 
  is 
  by 
  no 
  means 
  a 
  decisive 
  criterion, 
  as 
  some 
  Noctuae 
  

   (Acronycta) 
  and 
  Geometrae 
  (Tephrosia) 
  do 
  the 
  same. 
  Still, 
  I 
  think 
  a 
  Bombyx 
  maybe 
  

   known 
  with 
  tolerable 
  certainty, 
  if 
  attention 
  be 
  paid 
  to 
  the 
  following 
  peculiarities: 
  — 
  1. 
  

   A 
  web 
  or 
  cocoon. 
  2. 
  The 
  bulky 
  form 
  of 
  the 
  pupa, 
  which 
  is 
  almost 
  invariably 
  either 
  of 
  

   a 
  nearly 
  uniform 
  thickness 
  throughout, 
  and 
  round, 
  or 
  else 
  stout 
  to 
  the 
  middle 
  and 
  ra- 
  

   pidly 
  tapering 
  to 
  a 
  point. 
  3. 
  The 
  form 
  of 
  the 
  antennae 
  (which 
  is 
  an 
  excellent 
  criterion) 
  

   and 
  the 
  invariable 
  shortness 
  of 
  the 
  wing-cases 
  : 
  to 
  this 
  I 
  call 
  particular 
  attention. 
  Tb 
  

   genus 
  Lithosia, 
  of 
  which, 
  however, 
  I 
  know 
  only 
  two 
  species 
  in 
  the 
  pupa 
  state, 
  is 
  an 
  

   exception 
  to 
  some 
  of 
  these 
  rules. 
  Examjtles 
  of 
  the 
  rounded 
  form 
  will 
  occur 
  to 
  every 
  

   one, 
  as 
  Orgyia 
  potatoria, 
  Cerura 
  bifida, 
  C. 
  furcula, 
  &c. 
  As 
  an 
  example 
  of 
  the 
  taper- 
  

   ing 
  form 
  I 
  may 
  mention 
  Orgyia 
  Coryli. 
  Some 
  of 
  the 
  genera, 
  also, 
  among 
  the 
  Bom- 
  

   byces 
  may 
  readily 
  be 
  distinguished 
  by 
  the 
  form 
  of 
  the 
  pupae 
  ; 
  I 
  may 
  mention 
  in 
  parti- 
  

   cular 
  Notodonta. 
  I 
  think 
  I 
  could 
  instantly 
  detect 
  a 
  pupa 
  of 
  that 
  genus 
  from 
  its 
  form. 
  

   I 
  have 
  either 
  reared 
  or 
  found 
  in 
  pupa, 
  Notodonta 
  Camelina, 
  Chaonia, 
  Dicta-a, 
  Dic- 
  

   tceoides, 
  Dodona^a, 
  Dromedarius 
  trepida 
  and 
  Ziczac. 
  In 
  all 
  these 
  (with 
  the 
  exception 
  

   of 
  Camelina, 
  which 
  slightly 
  difler.s) 
  the 
  pupa 
  is 
  round 
  of 
  a 
  nearly 
  uniform 
  thickness, 
  

   rounded 
  at 
  the 
  anal 
  extremity, 
  and 
  ribbed. 
  

  

  " 
  The 
  genus 
  Lithosia 
  is 
  quite 
  different. 
  The 
  pupae 
  which 
  I 
  have 
  had 
  (L. 
  rubricol- 
  

   lis 
  and 
  aureola) 
  are 
  short 
  and 
  stout, 
  expanding 
  somewhat 
  in 
  the 
  middle, 
  and 
  tapering 
  

   slightly 
  towards 
  each 
  end. 
  

  

  \i 
  \i!.H. 
  1804 
  1' 
  

  

  