﻿PACKARD. 
  J 
  THE 
  GEAIN-APHIS. 
  711 
  

  

  must 
  be 
  cut 
  ofi", 
  tbe 
  virgin 
  females 
  produce 
  winged 
  individuals 
  of 
  both 
  

   sexes, 
  which 
  after 
  pairing 
  die, 
  after 
  depositing 
  their 
  eggs 
  for 
  the 
  spring 
  

   brood. 
  

  

  Our 
  species 
  is 
  oblong-oval 
  shaped, 
  narrowing 
  toward 
  the 
  head, 
  while 
  

   the 
  abdomen 
  behind 
  is 
  swelled 
  out 
  and 
  rather 
  blunt 
  at 
  the 
  end, 
  with 
  a 
  

   rather 
  long 
  ovipositor 
  in 
  tbe 
  female. 
  Its 
  color 
  is 
  green, 
  covered 
  often 
  

   with 
  a 
  reddish-brown 
  bloom. 
  The 
  ends 
  of 
  the 
  antennce, 
  the 
  end 
  of 
  the 
  

   shanks 
  and 
  thighs 
  and 
  the 
  feet, 
  are 
  black. 
  In 
  the 
  young, 
  these 
  parts 
  are 
  

   only 
  smoky 
  or 
  dusky. 
  Length 
  of 
  those 
  with 
  wings 
  about 
  one-tenth 
  of 
  

   an 
  inch. 
  

  

  Dr. 
  Fitch 
  gives 
  in 
  the 
  Boston 
  Courier, 
  interesting 
  observations 
  on 
  

   this 
  aphis. 
  Of 
  its 
  variation 
  in 
  color 
  he 
  says 
  : 
  "One 
  of 
  the 
  most 
  remark- 
  

   able 
  circumstances 
  relating 
  to 
  these 
  insects 
  is 
  the 
  change 
  in 
  their 
  color 
  

   which 
  now 
  began 
  to 
  take 
  place. 
  While 
  they 
  were 
  scattered 
  about 
  upon 
  

   the 
  leaves 
  and 
  stalks 
  of 
  the 
  grain, 
  they 
  were 
  of 
  a 
  bright 
  grass-green 
  

   color. 
  Now 
  orange-yellow 
  or 
  deep 
  tiesh-red 
  individuals 
  began 
  to 
  appear 
  

   among 
  them. 
  This 
  color 
  is 
  so 
  wholly 
  different 
  from 
  green, 
  that 
  these 
  

   orange 
  ones 
  might 
  be 
  suspected 
  to 
  be 
  a 
  different 
  species. 
  But 
  green 
  

   females 
  placed 
  in 
  vials 
  were 
  found 
  next 
  day 
  to 
  have 
  young 
  with 
  them 
  

   of 
  both 
  colors 
  ; 
  some 
  being 
  green, 
  others 
  orange. 
  And 
  a 
  few 
  days 
  later 
  

   other 
  green 
  females 
  were 
  found 
  to 
  have 
  orange 
  young 
  only, 
  no 
  green 
  

   ones 
  being 
  born 
  any 
  longer. 
  It 
  is 
  probably 
  the 
  change 
  in 
  the 
  quality 
  of 
  

   its 
  food 
  which 
  causes 
  the 
  insect 
  to 
  change 
  thus 
  in 
  its 
  color, 
  the 
  jhices 
  

   which 
  the 
  plant 
  elaborates 
  for 
  the 
  growth 
  of 
  its 
  flowers 
  and 
  seeds 
  being 
  

   much 
  more 
  highly 
  refined, 
  nutritious, 
  and 
  dainty 
  than 
  those 
  which 
  cir- 
  

   culate 
  in 
  the 
  stalks 
  and 
  leaves, 
  where 
  the 
  insect 
  first 
  feeds. 
  And 
  it 
  is 
  

   truly 
  curious 
  and 
  wonderful 
  that 
  this 
  green-colored 
  insect, 
  on 
  coming 
  to 
  

   feed 
  on 
  the 
  juices 
  which 
  grow 
  the 
  flowers, 
  begins 
  thereupon 
  to 
  give 
  birth 
  

   to 
  young 
  having 
  a 
  gray 
  orange 
  color 
  similar 
  to 
  that 
  of 
  the 
  flowers." 
  

  

  Dr. 
  Fitch 
  noticed 
  several 
  years 
  ago 
  in 
  wheat-fields 
  a 
  green 
  plant-louse, 
  

   though 
  it 
  was 
  not 
  common. 
  

  

  In 
  East 
  Hampden, 
  Mass., 
  "a 
  plant-louse 
  of 
  a 
  pale 
  brick-red 
  color 
  was 
  

   extremely 
  numerous" 
  in 
  1860 
  ; 
  so, 
  also, 
  a 
  "red 
  insect" 
  on 
  the 
  oats 
  in 
  jJ^^ew 
  

   York 
  was 
  sent 
  him. 
  We 
  thus 
  know 
  the 
  insect 
  we 
  are 
  to 
  speak 
  of 
  was 
  

   overrunning 
  the 
  fields 
  in 
  some 
  places 
  last 
  summer. 
  

  

  " 
  Early 
  in 
  May 
  last, 
  when 
  rye 
  and 
  winter- 
  wheat 
  were 
  but 
  a 
  few 
  inches 
  

   out 
  of 
  the 
  ground, 
  I 
  met 
  with 
  this 
  insect 
  more 
  numerous 
  than 
  any 
  other 
  

   in 
  every 
  -part 
  of 
  every 
  grain-field 
  in 
  my 
  neighborhood. 
  Toward 
  the 
  

   close 
  of 
  that 
  month 
  specimens 
  having 
  wings 
  began 
  to 
  occur. 
  By 
  in- 
  

   closing 
  them 
  singly 
  in 
  vials, 
  I 
  found 
  that 
  the 
  winged 
  female 
  usually 
  gave 
  

   birth 
  to 
  four 
  young 
  lice 
  in 
  twenty 
  four 
  hours, 
  while 
  those 
  without 
  wings 
  

   produced 
  eight 
  within 
  the 
  same 
  time." 
  

  

  The 
  grain-aphis 
  became 
  noticed 
  the 
  ISth 
  July 
  in 
  New 
  Jersey, 
  then 
  in 
  

   the 
  New 
  England 
  States. 
  Probably 
  very 
  few 
  farms 
  in 
  Maine 
  escaped 
  

   its 
  presence. 
  About 
  the 
  first 
  of 
  August 
  I 
  noticed 
  them 
  on 
  a 
  farm 
  about 
  

   thirty 
  miles 
  above 
  Mattawamkeag, 
  on 
  the 
  Penobscot 
  Eiver. 
  Also 
  on 
  

   farms 
  on 
  the 
  lakes 
  that 
  form 
  the 
  headwaters 
  of 
  the 
  Penobscot 
  and 
  Al- 
  

   leguash 
  Kivers, 
  and 
  on 
  the 
  Alleguash 
  and 
  Saint 
  John. 
  I 
  also 
  heard 
  of 
  

   its 
  occurrence 
  in 
  great 
  numbers 
  on 
  the 
  Saint 
  John 
  in 
  New 
  Brunswick. 
  

   Like 
  the 
  army-worm, 
  while 
  abundant 
  on 
  some 
  fields, 
  others 
  were 
  entirely 
  

   free 
  from 
  its 
  attacks. 
  

  

  The 
  injury 
  this 
  aphis 
  does 
  is 
  to 
  lessen 
  the 
  weight 
  of 
  the 
  grain, 
  which 
  

   of 
  course 
  is 
  a 
  matter 
  of 
  great 
  consequence. 
  The 
  constant 
  draining 
  of 
  

   the 
  sap 
  that 
  flows 
  into 
  the 
  ear 
  causes 
  it 
  to 
  be 
  very 
  light, 
  if 
  not 
  withered 
  

   and 
  worthless. 
  

  

  