﻿98 
  Dr. 
  G. 
  C. 
  Crampton's 
  Notes 
  on 
  the 
  Ancestry 
  of 
  the 
  

  

  relationships 
  of 
  these 
  insects, 
  since 
  it 
  would 
  require 
  a 
  

   figure 
  of 
  three 
  dimensions 
  to 
  show 
  that 
  one 
  fine 
  of 
  descent 
  

   is 
  in 
  some 
  cases 
  intermediate 
  between 
  several 
  others. 
  

   Furthermore, 
  it 
  would 
  make 
  too 
  comphcated 
  a 
  figure 
  to 
  

   attempt 
  to 
  include 
  in 
  the 
  diagram 
  all 
  of 
  the 
  lines 
  of 
  descent 
  

   of 
  the 
  insects 
  related 
  to 
  the 
  ancestors 
  of 
  the 
  Psocidae 
  and 
  

   the 
  Neuroptera, 
  so 
  that 
  but 
  a 
  few 
  of 
  these 
  have 
  been 
  

   included 
  in 
  the 
  diagram. 
  

  

  Among 
  the 
  most 
  important 
  of 
  the 
  insects 
  omitted 
  from 
  

   the 
  diagram 
  shown 
  in 
  Fig. 
  2 
  are 
  those 
  comprising 
  the 
  

   Blattoid 
  superorder 
  {i. 
  e. 
  the 
  Blattidae, 
  Mantidae, 
  Isoptera, 
  

   Zoraptera 
  and 
  their 
  fossil 
  relatives), 
  whose 
  lines 
  of 
  develop- 
  

   ment 
  may 
  be 
  thought 
  of 
  as 
  extending 
  in 
  a 
  plane 
  perpen- 
  

   dicular 
  to 
  that 
  containing 
  the 
  lines 
  of 
  descent 
  of 
  the 
  

   Psocidae 
  and 
  Neuroptera. 
  Now 
  certain 
  Mantidae, 
  such 
  

   as 
  Mantoida 
  luteola, 
  are 
  very 
  Neuropteron-hke, 
  and 
  certain 
  

   Isoptera 
  resemble 
  the 
  lower 
  Psocidae, 
  such 
  as 
  Archipsocus, 
  

   very 
  strongly, 
  so 
  that 
  it 
  is 
  quite 
  possible 
  that 
  the 
  Blattoid 
  

   superorder, 
  to 
  which 
  these 
  Mantids, 
  Isoptera, 
  etc., 
  belong, 
  

   more 
  nearly 
  represents 
  the 
  group 
  ancestral 
  to 
  the 
  Neuro- 
  

   ptera 
  than 
  the 
  Plecopteroid 
  superorder 
  does. 
  Indeed, 
  the 
  

   Isoptera 
  have 
  even 
  been 
  classed 
  with 
  the 
  " 
  Neuroptera 
  " 
  

   by 
  some 
  entomologists 
  who 
  were 
  apparently 
  impressed 
  with 
  

   their 
  Neuropteron-hke 
  appearance. 
  On 
  the 
  other 
  hand, 
  

   the 
  Embiid 
  and 
  Plecopteron 
  representatives 
  of 
  the 
  Pleco- 
  

   pteroid 
  superorder 
  have 
  likewise 
  been 
  classed 
  as 
  " 
  Neuro- 
  

   ptera 
  " 
  by 
  some 
  entomologists 
  who 
  were 
  apparently 
  im- 
  

   pressed 
  with 
  the 
  Neuropterous 
  affinities 
  of 
  these 
  insects, 
  

   and 
  when 
  one 
  takes 
  into 
  consideration 
  the 
  close 
  relationship 
  

   of 
  the 
  Psocidae 
  to 
  the 
  Coleoptera, 
  Dermaptera, 
  Embiidae 
  

   and 
  Plecoptera 
  (i. 
  e. 
  the 
  Plecopteroid 
  superorder) 
  in 
  

   addition 
  to 
  the 
  marked 
  resemblance 
  of 
  the 
  Neuroptera 
  to 
  

   certain 
  of 
  these 
  insects, 
  there 
  are 
  very 
  good 
  reasons 
  for 
  

   considering 
  the 
  Plecopteroid 
  superorder 
  rather 
  than 
  the 
  

   Blattoid 
  superorder 
  as 
  more 
  nearly 
  representing 
  the 
  group 
  

   which 
  gave 
  rise 
  to 
  the 
  lines 
  of 
  descent 
  of 
  the 
  insects 
  related 
  

   to 
  the 
  Psocidae 
  and 
  Neuroptera. 
  In 
  the 
  foregoing 
  discus- 
  

   sion 
  it 
  should 
  be 
  clearly 
  understood 
  that 
  the 
  Plecopteron 
  

   section, 
  which 
  includes 
  the 
  Blattoid, 
  Orthopteroid 
  and 
  

   Plecopteroid 
  superorders, 
  is 
  a 
  more 
  inclusive 
  designation 
  

   than 
  the 
  Plecopteroid 
  superorder, 
  which 
  constitutes 
  merely 
  

   a 
  portion 
  of 
  the 
  insects 
  included 
  in 
  the 
  Plecopteron 
  section. 
  

  

  It 
  is 
  perhaps 
  a 
  rather 
  unfortunate 
  choice 
  to 
  begin 
  the 
  

   discussion 
  of 
  the 
  ancestry 
  and 
  interrelationships 
  of 
  the 
  

  

  