﻿136 
  

  

  idae, 
  Siegius 
  and 
  Eriximachus 
  in 
  the 
  Reduviidae, 
  described 
  

   by 
  Distant, 
  and 
  Acanthicus 
  of 
  Laporte 
  in 
  tbe 
  Membracidae. 
  

  

  Hemiptera 
  usually 
  deposit 
  their 
  ova 
  on 
  the 
  surface 
  of 
  leaves 
  

   or 
  twigs, 
  or 
  insert 
  them 
  in 
  slits 
  made 
  in 
  these. 
  The 
  nymphs 
  

   are 
  usually 
  free, 
  but 
  in 
  some 
  groups 
  are 
  concealed 
  in 
  spume 
  or 
  

   in 
  calcareous 
  cases, 
  while 
  a 
  few 
  form 
  galls. 
  They 
  differ 
  from 
  

   their 
  adults 
  principally 
  by 
  the 
  condition 
  of 
  the 
  flight 
  organs, 
  

   which 
  are 
  gradually 
  developed 
  outside 
  the 
  body, 
  forming 
  in 
  the 
  

   ultimate 
  n;}T2iphal 
  instar 
  four, 
  more 
  or 
  less 
  free, 
  pads. 
  Other 
  

   distinctions 
  lie 
  in 
  the 
  number 
  and 
  form 
  of 
  the 
  segments 
  of 
  the 
  

   antennae, 
  labium 
  and 
  legs, 
  the 
  absence 
  of 
  ocelli, 
  the 
  shape 
  of 
  

   the 
  head 
  and 
  nota, 
  and 
  the 
  development 
  of 
  the 
  genitalia. 
  

  

  In 
  the 
  early 
  instars, 
  the 
  abdomen 
  is 
  only 
  feebly 
  chitinized 
  

   and, 
  in 
  some 
  families 
  at 
  least, 
  there 
  are 
  median 
  and 
  lateral 
  

   sternites, 
  with 
  very 
  wide 
  sublateral 
  submembranous 
  parts, 
  the 
  

   sclerites 
  down 
  the 
  middle 
  also 
  being 
  widely 
  separated 
  one 
  from 
  

   another. 
  As 
  the 
  instars 
  progress, 
  the 
  membranous 
  areas 
  

   decrease, 
  till 
  they 
  constitute 
  merely 
  linear 
  separations 
  between 
  

   the 
  segments, 
  in 
  the 
  fifth 
  instar. 
  

  

  In 
  most 
  Hemiptera, 
  there 
  are 
  apparently 
  5 
  nymphal 
  instars. 
  

   It 
  is 
  still 
  often 
  stated 
  as 
  4 
  larval 
  and 
  one 
  pupal, 
  but 
  these 
  are 
  

   terms 
  that 
  have 
  no 
  place 
  rightly 
  in 
  the 
  horismology 
  of 
  the 
  

   Homomorpha. 
  

  

  In 
  the 
  Homoptera, 
  adult 
  or 
  nymphs, 
  there 
  are 
  no 
  odoriferous 
  

   glands 
  though 
  in 
  certain 
  Sternorhynchi 
  there 
  are 
  ''honey- 
  

   glands." 
  In 
  most 
  adult 
  Heteroptera, 
  the 
  orifices 
  of 
  the 
  noto- 
  

   rious 
  odoriferous 
  gland 
  are 
  situated 
  on 
  the 
  metapleura, 
  though 
  

   in 
  some 
  there 
  is 
  a 
  single 
  opening 
  on 
  the 
  metasternum 
  medianly 
  

   and 
  in 
  a 
  few 
  the 
  glands 
  appear 
  to 
  be 
  absent. 
  

  

  In 
  the 
  nymphs 
  of 
  the 
  first 
  series, 
  the 
  openings 
  are 
  placed 
  on 
  

   the 
  (abdominal) 
  tergites 
  and 
  afford 
  valuable 
  classificational 
  

   characters, 
  which 
  have 
  been 
  partially 
  worked 
  out 
  O 
  but 
  

   require 
  much 
  extension. 
  

  

  According 
  to 
  Guide's 
  researches, 
  it 
  may 
  be 
  supposed 
  that 
  the 
  

   Cimicidae, 
  Aradidae, 
  Nabidae, 
  Eeduviidae, 
  Anthocoridae 
  and 
  

   Clinocoridae 
  possess 
  3 
  glands, 
  opening 
  on 
  the 
  fourth, 
  fifth 
  and 
  

   sixth 
  tergites 
  (^) 
  ; 
  of 
  these, 
  the 
  first 
  is 
  paired, 
  having 
  two 
  

   openings, 
  in 
  many 
  of 
  the 
  Cimicidae. 
  In 
  Lygaeidae, 
  Neididae, 
  

  

  (4) 
  In 
  a 
  valuable 
  paper 
  by 
  Guide, 
  entitled 
  "Die 
  Dorsaldriisen 
  der 
  

   Larven 
  der 
  Hemiptera-Heteroptera", 
  1902 
  Ber. 
  Senckenb. 
  Naturf. 
  Ges. 
  

   Frankf. 
  a 
  M. 
  85-136, 
  Plates 
  7-8. 
  

  

  (5) 
  This 
  applies 
  apparently 
  only 
  to 
  the 
  5th 
  instar. 
  

  

  