﻿Diptera, 
  Hemiptera 
  and 
  Insects 
  related 
  to 
  Neuroptera. 
  97 
  

  

  Dermaptera, 
  Embiidae 
  and 
  Plecoptera, 
  which 
  constitute 
  

   the 
  Plecopteroid 
  superorder 
  (Jour. 
  N.Y. 
  Ent. 
  Soc, 
  vol. 
  25, 
  

   1917, 
  p. 
  230), 
  and, 
  since 
  the 
  Neuroptera 
  also 
  exhibit 
  many 
  

   features 
  in 
  common 
  with 
  the 
  Embiid 
  and 
  Plecopteron 
  

   members 
  of 
  this 
  same 
  Plecopteroid 
  superorder, 
  I 
  am 
  in- 
  

   chned 
  to 
  consider 
  that, 
  taken 
  as 
  a 
  whole 
  (and 
  not 
  merely 
  

   considering 
  the 
  Neuroptera 
  alone), 
  the 
  Unes 
  of 
  descent 
  

   of 
  the 
  insects 
  of 
  the 
  Neuropteron 
  section 
  would 
  lead 
  back 
  

   to 
  the 
  Plecopteron 
  section 
  more 
  directly, 
  and 
  ultimately 
  

  

  HOMOPTERA 
  

   HEMIPTERA 
  

  

  PEDICULIDAE 
  

  

  MALLOPHAGA 
  

   PSOCIDAE 
  

  

  THYSANOPTERA 
  

   STREPSIPTERA 
  

  

  COLEOPTERA, 
  

   DERMAPTERA 
  

   PLECOPTERA 
  

  

  HYMENOPTERA 
  

  

  SIPHON 
  APTERA 
  

  

  DIPTERA 
  

   MECOPTERA 
  

  

  TRICHOPTERA 
  

   LEPIDOPTERA 
  

  

  rJEUROPTERA 
  

  

  ^EPHEMERIDA 
  

   .PALAEODICTYOPTERA 
  

  

  Fig. 
  2. 
  

  

  through 
  or 
  with 
  them, 
  to 
  ancestors 
  resembhng 
  the 
  insects 
  

   of 
  the 
  Ephemerid 
  section. 
  On 
  this 
  account, 
  I 
  have 
  repre- 
  

   sented 
  the 
  Palaeodictyoptera 
  and 
  Ephemerida 
  as 
  occupying 
  

   positions 
  near 
  the 
  base 
  of 
  the 
  common 
  stem 
  in 
  Fig. 
  2, 
  

   while 
  the 
  Plecoptera 
  and 
  their 
  alhes 
  are 
  shown 
  somewhat 
  

   nearer 
  to 
  the 
  point 
  where 
  the 
  hues 
  of 
  descent 
  of 
  the 
  insects 
  

   related 
  to 
  the 
  Psocidae 
  and 
  Neuroptera 
  have 
  branched 
  off. 
  

   It 
  should 
  be 
  borne 
  in 
  mind 
  that 
  the 
  diagram 
  of 
  the 
  lines 
  

   of 
  descent 
  shown 
  in 
  Fig. 
  2 
  is 
  intended 
  merely 
  to 
  aid 
  in 
  

   visuahsing 
  the 
  relative 
  positions 
  of 
  the 
  insects 
  in 
  question, 
  

   and 
  it 
  does 
  not 
  accurately 
  represent 
  the 
  actual 
  inter- 
  

  

  TRANS. 
  ENT. 
  SOC. 
  LOND. 
  1919. 
  — 
  PARTS 
  I, 
  II. 
  (jULY) 
  H 
  

  

  