﻿Diptera, 
  Hemiptera 
  and 
  Insects 
  related 
  to 
  Neuroptera. 
  117 
  

  

  Certain 
  of 
  the 
  earUer 
  entomologists 
  {e.g. 
  Latreille, 
  1831, 
  

   Newman, 
  1834, 
  etc.), 
  and 
  more 
  recently 
  Banks, 
  are 
  inclined 
  

   to 
  include 
  the 
  Isoptera 
  with 
  the 
  Neuroptera. 
  The 
  Mantidae 
  

   (which 
  belong 
  in 
  the 
  same 
  superorder 
  with 
  the 
  Isoptera) 
  

   also 
  show 
  some 
  affinities 
  with 
  the 
  Neuroptera 
  ; 
  but 
  I 
  am 
  

   inchned 
  to 
  interpret 
  these 
  resemblances 
  as 
  the 
  result 
  of 
  

   the 
  retention 
  of 
  certain 
  primitive 
  features 
  inherited 
  from 
  

   the 
  common 
  Plecopteroid 
  ancestry 
  from 
  which 
  were 
  derived- 
  

   the 
  Isoptera, 
  Mantidae, 
  etc., 
  on 
  the 
  one 
  hand, 
  and 
  the 
  

   Neuroptera, 
  with 
  their 
  alhes, 
  on 
  the 
  other. 
  Through 
  this 
  

   Plecopteroid 
  ancestry, 
  the 
  line 
  of 
  development 
  of 
  the 
  

   Neuroptera 
  leads 
  back 
  ultimately 
  to 
  forbears 
  related 
  to 
  

   the 
  Palaeodictyoptera, 
  and 
  other 
  insects 
  belonging 
  to 
  the 
  

   Ephemerid 
  group 
  (in 
  which 
  the 
  Megasecoptera 
  might 
  also 
  

   be 
  included). 
  The 
  relationship 
  of 
  the 
  Neuroptera 
  to 
  the 
  

   Mecoptera 
  certainly 
  seems 
  very 
  much 
  closer 
  than 
  would 
  

   be 
  indicated 
  by 
  Handhrsch's 
  deriving 
  the 
  Mecoptera 
  from 
  

   Megasecoptera 
  while 
  deriving 
  the 
  Neuroptera 
  from 
  Palaeo- 
  

   dictyoptera 
  ; 
  and 
  the 
  facts 
  of 
  comparative 
  anatomy 
  (not 
  

   based 
  upon 
  the 
  study 
  of 
  wings 
  alone) 
  would 
  certainly 
  appear 
  

   to 
  be 
  more 
  in 
  harmony 
  with 
  the 
  derivation 
  shown 
  in 
  Fig. 
  2, 
  

   in 
  which 
  the 
  lines 
  of 
  descent 
  of 
  the 
  Mecoptera 
  and 
  their 
  

   alhes 
  are 
  represented 
  as 
  quickly 
  merging 
  with 
  that 
  of 
  the' 
  

   Neuroptera, 
  which 
  soon 
  unites 
  with 
  the 
  main 
  stem 
  of 
  the 
  

   Psocidae 
  and 
  their 
  allies 
  to 
  form 
  a 
  main 
  Neuropterous 
  

   group 
  stem. 
  This 
  in 
  turn 
  merges 
  with 
  the 
  hues 
  of 
  develop- 
  

   ment 
  of 
  the 
  Plecopteroid 
  forms, 
  which 
  are 
  later 
  joined 
  by 
  

   the 
  lines 
  of 
  development 
  of 
  the 
  Megasecoptera, 
  Palaeo- 
  

   dictyoptera 
  and 
  other 
  insects 
  belonging 
  to 
  the 
  Ephemerid 
  

   group. 
  

  

  It 
  may 
  be 
  mentioned 
  in 
  closing, 
  that 
  the 
  insects 
  related 
  

   to 
  the 
  Neuroptera 
  fall 
  into 
  two 
  superorders, 
  each 
  of 
  which 
  

   contains 
  some 
  insects 
  very 
  closely 
  alhed 
  to 
  certain 
  members 
  

   of 
  the 
  other 
  superorder; 
  but 
  each 
  group 
  is 
  fairly 
  well 
  

   defined. 
  Of 
  these 
  insects, 
  the 
  Neuroptera, 
  Lepidoptera, 
  

   Trichoptera, 
  Mecoptera, 
  Diptera, 
  Siphonaptera 
  and 
  the 
  

   Hymenoptera 
  (together 
  with 
  their 
  fossil 
  relatives) 
  may 
  be 
  

   grouped 
  in 
  a 
  superorder 
  called 
  the 
  Panneuroptera 
  (Psyche, 
  

   vol. 
  25, 
  1918, 
  p. 
  55), 
  characterised 
  in 
  general 
  by 
  the 
  reten- 
  

   tion 
  of 
  five 
  segments 
  in 
  the 
  tarsi, 
  the 
  division 
  of 
  the 
  meso- 
  

   thoracic 
  coxae 
  by 
  an 
  approximately 
  vertical 
  suture 
  (which 
  

   is 
  present 
  in 
  the 
  lower 
  representatives 
  of 
  the 
  Diptera, 
  

   despite 
  the 
  frequent 
  statements 
  to 
  the 
  contrary 
  — 
  see 
  

   Crampton 
  and 
  Hasey, 
  1915, 
  " 
  The 
  Basal 
  Segments 
  of 
  the 
  

  

  