﻿art. 
  20 
  THE 
  APHID 
  GENUS 
  AMPHOBOPHOEA 
  MASON 
  5 
  

  

  cornicles. 
  In 
  Megoura 
  they 
  are 
  practically 
  the 
  same 
  thickness 
  from 
  

   the 
  base 
  to 
  the 
  center, 
  after 
  which 
  they 
  narrow 
  to 
  the 
  flange. 
  This 
  

   often 
  gives 
  the 
  center 
  the 
  appearance 
  of 
  a 
  slight 
  bulge. 
  In 
  Amphor- 
  

   ophora 
  the 
  cornicle 
  narrows 
  considerably 
  between 
  the 
  base 
  and 
  the 
  

   swollen 
  central 
  portion, 
  giving 
  an 
  actual, 
  conspicuous 
  dilation. 
  

  

  In 
  the 
  tables 
  of 
  measurements 
  the 
  first 
  line 
  for 
  each 
  specimen 
  refers 
  

   to 
  the 
  left 
  side, 
  such 
  as 
  left 
  antenna 
  or 
  left 
  cornicle. 
  

  

  When 
  a 
  species 
  is 
  described 
  from 
  one 
  specimen 
  only, 
  this 
  speci- 
  

   men 
  is 
  designated 
  as 
  the 
  type. 
  

  

  When 
  a 
  species 
  is 
  described 
  from 
  several 
  specimens, 
  all 
  from 
  the 
  

   same 
  colony, 
  these 
  specimens 
  are 
  designated 
  as 
  cotypes, 
  and 
  there 
  

   is 
  no 
  type. 
  

  

  When 
  a 
  species 
  is 
  described 
  from 
  several 
  specimens 
  taken 
  from 
  

   different 
  colonies, 
  either 
  in 
  the 
  same 
  or 
  different 
  localities, 
  the 
  speci- 
  

   mens 
  from 
  one 
  colony 
  are 
  designated 
  as 
  cotypes, 
  those 
  from 
  the 
  

   other 
  colonies 
  as 
  paracotypes. 
  

  

  The 
  following 
  keys 
  will 
  help 
  to 
  separate 
  the 
  species. 
  It 
  has 
  been 
  

   necessary 
  to 
  omit 
  betae 
  from 
  the 
  keys 
  as 
  no 
  specimens 
  were 
  avail- 
  

   able 
  for 
  study 
  and 
  the 
  published 
  description 
  does 
  not 
  give 
  sufficient 
  

   details. 
  

  

  KEY 
  TO 
  ALATE 
  VIVIPAROUS 
  FEMALES 
  5 
  

  

  1 
  . 
  Cornicles 
  distinctly 
  reticulated 
  2 
  

  

  Cornicles 
  not 
  reticulated, 
  often 
  imbricated 
  at 
  tip 
  15 
  

  

  2. 
  Cornicles 
  shorter 
  than 
  segment 
  III 
  of 
  antennae 
  3 
  

  

  Cornicles 
  equal 
  to 
  or 
  longer 
  than 
  segment 
  III 
  11 
  

  

  3. 
  Segment 
  III 
  of 
  antennae 
  light 
  colored 
  corylina 
  (Davidson). 
  

  

  Segment 
  III 
  of 
  antennae 
  dark 
  colored 
  4 
  

  

  4. 
  Segment 
  IV 
  longer 
  than 
  V 
  5 
  

  

  Segment 
  IV 
  shorter 
  than 
  V 
  10 
  

  

  5. 
  Cornicles 
  not 
  longer 
  than 
  width 
  of 
  head 
  through 
  eyes 
  6 
  

  

  Cornicles 
  considerably 
  longer 
  than 
  width 
  of 
  head 
  through 
  eyes 
  8 
  

  

  6. 
  Segment 
  IV 
  with 
  sensoria 
  brittenii 
  (Theobald). 
  

  

  Segment 
  IV 
  without 
  sensoria 
  7 
  

  

  7. 
  Cauda 
  with 
  about 
  six 
  lateral 
  hairs. 
  Cornicles 
  very 
  broad. 
  

  

  essigwanai, 
  new 
  name. 
  

   Cauda 
  with 
  about 
  two 
  lateral 
  hairs. 
  Cornicles 
  more 
  slender 
  (On 
  Acon- 
  

  

  itum) 
  aconiti 
  (v. 
  d. 
  Goot). 
  

  

  S. 
  Ill 
  with 
  a 
  row 
  of 
  about 
  16 
  sensoria 
  vaccinii, 
  new 
  species. 
  

  

  Antennae 
  with 
  numerous 
  senoria 
  9 
  

  

  9. 
  V 
  with 
  14-15 
  senoria 
  hayhursti, 
  new 
  species. 
  

  

  V 
  with 
  5-10 
  sensoria 
  mitchelli, 
  new 
  species. 
  

  

  10. 
  Smallest 
  diameter 
  of 
  cornicle 
  one-half 
  of 
  widest 
  diameter 
  (On 
  Spiraea). 
  

  

  spiraecola 
  (Patch). 
  

   Smallest 
  diameter 
  of 
  cornicle 
  two-thirds 
  of 
  widest 
  diameter 
  (On 
  Rubus). 
  

  

  reticulata, 
  new 
  species. 
  

  

  11. 
  IV 
  with 
  sensoria 
  brittenii 
  (Theobald). 
  

  

  IV 
  without 
  sensoria 
  12 
  

  

  6 
  Roman 
  numerals 
  refer 
  to 
  the 
  number 
  of 
  the 
  segment 
  of 
  the 
  antenna, 
  as 
  segment 
  III. 
  

  

  