﻿[79] 
  Notes 
  on 
  Notodonta 
  dictcea. 
  191 
  

  

  enigma 
  to 
  me, 
  to 
  the 
  imago 
  which 
  they 
  produce, 
  which 
  is 
  ap- 
  

   parently 
  identical 
  with 
  the 
  Notodonta 
  dictcea 
  of 
  Europe. 
  

  

  I 
  regret 
  that 
  I 
  have 
  not 
  at 
  hand 
  a 
  detailed 
  description 
  of 
  

   the 
  European 
  larva, 
  to 
  compare 
  with 
  our 
  own. 
  Stephens 
  

   (Illustrations 
  of 
  British 
  Entomology, 
  Haust. 
  II, 
  p. 
  25), 
  says 
  

   of 
  it: 
  "Larva 
  naked, 
  with 
  a 
  small 
  conical 
  protruberance 
  on 
  

   the 
  anal 
  segment 
  ; 
  reddish-brown, 
  green 
  on 
  the 
  sides 
  and 
  

   glossed 
  with 
  violet 
  above, 
  with 
  a 
  black 
  dorsal 
  streak 
  : 
  it 
  feeds 
  

   on 
  poplar, 
  willow 
  and 
  birch, 
  and 
  is 
  found 
  in 
  July 
  and 
  

   September.' 
  ' 
  

  

  Newman, 
  in 
  his 
  History 
  of 
  British 
  Moths, 
  page 
  228, 
  gives 
  

   the 
  following 
  description 
  : 
  ' 
  ' 
  The 
  caterpillar 
  has 
  rather 
  a 
  large 
  

   head, 
  which 
  is 
  very 
  slightly 
  notched 
  on 
  the 
  crown 
  and 
  shin- 
  

   ing, 
  and 
  is 
  of 
  a 
  pale 
  green 
  color. 
  The 
  body 
  is 
  almost 
  uni- 
  

   formly 
  cylindrical 
  until 
  the 
  twelfth 
  segment, 
  which 
  is 
  humped, 
  

   and 
  the 
  hump 
  terminating 
  in 
  a 
  moderately 
  sharp 
  point 
  ; 
  the 
  

   color 
  of 
  the 
  body 
  is 
  whitish 
  or 
  glaucous-green 
  on 
  the 
  back, 
  

   with 
  a 
  broad 
  paler 
  green 
  stripe 
  on 
  each 
  side 
  — 
  and 
  adjoining 
  

   this 
  there 
  is 
  a 
  narrow 
  raised 
  yellow-green 
  stripe, 
  just 
  below 
  

   the 
  spiracles, 
  and 
  touching 
  all 
  of 
  them 
  except 
  that 
  on 
  the 
  

   twelfth 
  segment 
  ; 
  it 
  extends 
  the 
  entire 
  length 
  of 
  the 
  caterpillar, 
  

   terminating 
  in 
  the 
  anal 
  claspers; 
  on 
  the 
  summit 
  of 
  the 
  twelfth 
  

   or 
  hump 
  segment, 
  is 
  a 
  black 
  transverse 
  line. 
  It 
  feeds 
  on 
  the 
  

   sallow 
  (Populus 
  nigra), 
  etc. 
  There 
  is 
  a 
  common 
  variety 
  of 
  

   this 
  caterpillar 
  which 
  is 
  plain 
  brown, 
  without 
  the 
  slightest 
  

   appearance 
  of 
  the 
  lateral 
  stripe; 
  this 
  occurs 
  after 
  the 
  last 
  

   change 
  of 
  skin." 
  

  

  Dr. 
  Speyer 
  writes 
  of 
  the 
  larva 
  of 
  the 
  European 
  N. 
  dictcea 
  : 
  

   It 
  has 
  a 
  tubercle 
  of 
  pyramidal 
  shape 
  on 
  the 
  11th 
  segment, 
  

   which 
  is 
  much 
  more 
  pointed 
  in 
  the 
  younger 
  stages 
  of 
  the 
  larva, 
  

   so 
  as 
  closely 
  to 
  resemble 
  the 
  horn 
  of 
  a 
  Sphinx. 
  The 
  mature 
  

   larva 
  has 
  a 
  strong 
  porcelain 
  lustre, 
  and 
  occurs 
  in 
  two 
  varie- 
  

   ties 
  : 
  one 
  is 
  of 
  a 
  green 
  color 
  with 
  a 
  yellow 
  stripe 
  on 
  its 
  sides, 
  

   and 
  the 
  other 
  is 
  brown 
  without 
  the 
  stripe. 
  It 
  lives 
  on 
  poplar. 
  

  

  Several 
  examples 
  of 
  the 
  American 
  i\T. 
  dictcea 
  were 
  sent 
  by 
  

   Mr. 
  von 
  Meske 
  to 
  Dr. 
  Speyer 
  to 
  compare 
  with 
  the 
  European 
  

   forms. 
  Having 
  made 
  the 
  comparison, 
  he 
  does 
  not 
  doubt 
  that 
  

   they 
  are 
  identical, 
  although 
  the 
  following 
  differences 
  are 
  no- 
  

   ticeable. 
  " 
  The 
  American 
  form 
  has 
  a 
  bent 
  white 
  cross-line 
  on 
  

   the 
  inner 
  part 
  of 
  the 
  brown 
  portion 
  of 
  the 
  anal 
  angle 
  of 
  

   the 
  secondaries, 
  which 
  is 
  not 
  found 
  in 
  the 
  European. 
  In 
  the 
  

   former 
  the 
  interior 
  branch 
  of 
  the 
  median 
  nervure 
  [vein 
  2] 
  has 
  

  

  