﻿DESCRIPTION 
  OF 
  THE 
  NEUEOPTERA. 
  293 
  

  

  markable, 
  mask-like 
  labium. 
  The 
  abdomen 
  is 
  very 
  long, 
  slender 
  and 
  

   cylindrical; 
  there 
  are 
  eleven 
  uromeres, 
  the 
  eleventh 
  being 
  well 
  repre- 
  

   sented, 
  while 
  the 
  cercopoda 
  are 
  not 
  jointed, 
  but 
  in 
  the 
  form 
  of 
  clampers. 
  

  

  3. 
  Epliemerina, 
  — 
  In 
  the 
  small 
  epicranium, 
  and 
  the 
  large 
  male 
  eyes, 
  the 
  

   Ephemerina 
  resemble 
  the 
  Odonata, 
  though 
  the 
  rudimentary 
  mouth- 
  

   parts 
  are 
  in 
  plan 
  entirely 
  unlike 
  them. 
  So, 
  also, 
  the 
  prothorax 
  is 
  small 
  

   and 
  annular, 
  but 
  the 
  subspherical, 
  concentrated 
  thorax 
  is 
  remarkable 
  for 
  

   the 
  large 
  mesothorax 
  and 
  the 
  small 
  metathorax. 
  Hence 
  the 
  hind 
  wings 
  

   are 
  small 
  and 
  sometimes 
  obsolete. 
  The 
  long, 
  slender 
  abdomen 
  has 
  ten 
  

   uromeres, 
  and 
  bears, 
  besides 
  the 
  two 
  long, 
  filamental 
  multiarticulate 
  

   cercopoda, 
  a 
  third 
  median 
  one. 
  

  

  The 
  larv£e 
  of 
  the 
  lower 
  Odonata 
  and 
  of 
  the 
  Ephemeridse 
  closely 
  ap- 
  

   proach 
  in 
  form 
  those 
  of 
  the 
  Perlidse, 
  showing 
  that 
  the 
  three 
  suborders 
  

   here 
  mentioned 
  probably 
  had 
  a 
  common 
  ancestry, 
  which 
  can 
  be 
  theo- 
  

   retically 
  traced 
  to 
  a 
  form 
  not 
  remote 
  from 
  Oampodea. 
  By 
  reason 
  of 
  the 
  

   general 
  resemblance 
  of 
  the 
  larval 
  forms 
  of 
  these 
  three 
  suborders 
  it 
  would 
  

   be 
  inadvisable 
  to 
  separate 
  the 
  Odonata 
  and 
  Ephemerina 
  from 
  the 
  Pla- 
  

   typtera, 
  although, 
  when 
  we 
  consider 
  the 
  adult 
  forms 
  alone, 
  there 
  would 
  

   appear 
  to 
  be 
  some 
  grounds 
  for 
  such 
  a 
  division. 
  

  

  Order 
  4. 
  NEUEOPTERA. 
  

  

  The 
  head 
  is 
  horizontal 
  and 
  somewhat 
  flattened, 
  except 
  in 
  the 
  Trich- 
  

   optera 
  and 
  Panorpidai, 
  where 
  it 
  is 
  subspherical 
  and 
  vertical. 
  The 
  body 
  

   shows 
  a 
  tendency 
  to 
  be 
  round 
  or 
  cylindrical, 
  the 
  thorax 
  being 
  more 
  or 
  

   less 
  spherical, 
  but 
  there 
  is 
  great 
  diversity 
  in 
  form 
  from 
  the 
  Sialidse 
  to 
  

   the 
  Trichoptera. 
  The 
  mouth-parts 
  are 
  free 
  and 
  the 
  mandibles 
  well 
  de- 
  

   veloped, 
  except 
  in 
  the 
  Trichoptera, 
  where 
  the 
  mandibles 
  are 
  nearly 
  

   obsolete 
  in 
  form, 
  and 
  functionless, 
  thus 
  suggesting 
  or 
  anticipating 
  the 
  

   Lepidoptera. 
  

  

  In 
  the 
  Neuroptera 
  the 
  ligula 
  is 
  entirely 
  unlike 
  any 
  of 
  the 
  foregoing 
  

   and 
  lower 
  groups. 
  It 
  is 
  entire, 
  forming 
  a 
  broad, 
  flat, 
  large, 
  rounded 
  

   lobe; 
  it 
  is 
  largest 
  in 
  Myrmeleon, 
  Ascala]3hus, 
  and 
  Mantispa, 
  but 
  smaller 
  

   in 
  Oorydalis, 
  where 
  it 
  is 
  also 
  narrower, 
  and 
  indented 
  on 
  the 
  front 
  edge. 
  

  

  In 
  Panorpa 
  the 
  ligula 
  is 
  minute, 
  rudimentary 
  (PI. 
  LIX, 
  fig. 
  7). 
  In 
  

   the 
  Trichoptera 
  it 
  is 
  also 
  minute 
  and 
  rudimentary 
  (PI. 
  LIX,. 
  fig. 
  5). 
  

  

  The 
  prothorax 
  is 
  usually 
  (Planipennia) 
  large, 
  broad, 
  and 
  square, 
  but 
  

   is 
  ring- 
  or 
  collar-like 
  in 
  the 
  Trichoptera, 
  being 
  short 
  and 
  small, 
  much 
  

   as 
  in 
  Lepidoptera. 
  Except 
  in 
  the 
  Trichoptera, 
  the 
  meso- 
  and 
  metanotum 
  

   are 
  characterized 
  by 
  the 
  large, 
  cordate 
  prtescutum, 
  and 
  in 
  the 
  Hemero- 
  

   bina 
  the 
  metascutum 
  is 
  partially 
  or 
  (in 
  Ascalaphus) 
  wholly 
  cleft, 
  the 
  

   prsescutum 
  and 
  scutellum 
  meeting 
  on 
  the 
  median 
  line 
  of 
  the 
  thorax. 
  

  

  In 
  the 
  Hemerobina 
  and 
  Sialidse 
  the 
  metathorax 
  is 
  as 
  large, 
  or 
  nearly 
  

   as 
  large, 
  as 
  the 
  mesothorax, 
  and 
  the 
  hind 
  wings 
  are 
  as 
  large 
  as 
  the 
  

   anterior 
  pair. 
  The 
  wings 
  are 
  not 
  net- 
  veined, 
  the 
  type 
  of 
  venation 
  being 
  

   entirely 
  unlike 
  that 
  of 
  the 
  Orthoi3tera 
  and 
  Pseudoneuroptera. 
  The 
  

  

  