﻿PACKAra).J 
  

  

  THE 
  WHEAT-THRIPS 
  THE 
  WHEAT-WOEM. 
  

  

  713 
  

  

  Tliey 
  were 
  mostly 
  at 
  rest, 
  reclining 
  at 
  full 
  length 
  on 
  the 
  ytraw, 
  while 
  

   only 
  a 
  few 
  were 
  feeding 
  on 
  the 
  ears." 
  

  

  Larva. 
  — 
  The 
  best 
  marked 
  worms 
  are 
  prettily 
  striped 
  witli 
  sulpliur-yellow 
  and 
  straw- 
  

   yellow, 
  and 
  with 
  light 
  and 
  dark 
  brown, 
  as 
  follows: 
  A 
  broad, 
  dark 
  -brown 
  line 
  along 
  the 
  

   "back, 
  divided 
  along 
  the 
  middle 
  by 
  a 
  hue 
  white 
  line 
  generally 
  obsolete 
  behind 
  ; 
  beneath 
  

   this 
  broad 
  line 
  on 
  each 
  side 
  a 
  straw-yellow 
  line, 
  half 
  as 
  wide 
  ; 
  then 
  a 
  light-brown 
  one 
  of 
  

   the 
  same 
  width 
  as 
  the 
  last, 
  and 
  becoming 
  yellow 
  on 
  the 
  lower 
  edge 
  ; 
  then 
  a 
  narrower 
  

   dark-brown 
  one, 
  containing 
  the 
  white 
  spiracles 
  ; 
  then 
  a 
  sulphur-yellow 
  as 
  wide 
  as 
  the 
  

   third 
  ; 
  then 
  a 
  less 
  distinct 
  light-brown 
  subventral 
  one, 
  the 
  venter 
  being 
  pale 
  yellow. 
  

   The 
  head 
  is 
  large, 
  straw-colored, 
  and 
  with 
  two 
  attenuating 
  brown 
  marks 
  from 
  the 
  top 
  

   to 
  the 
  lower 
  face. 
  The 
  chrysalis 
  is 
  of 
  the 
  ordinary 
  mahogany-brown 
  color, 
  and 
  termi- 
  

   nates 
  in 
  a 
  stout 
  horny 
  point, 
  with 
  a 
  corrugated 
  base. 
  

  

  Adult. 
  — 
  The 
  moth 
  has 
  the 
  front 
  wings 
  straw-colored, 
  with 
  a 
  pale 
  line 
  running 
  along 
  

   the 
  middle 
  to 
  the 
  outer 
  third, 
  and 
  shaded 
  with 
  brown 
  as 
  follows 
  : 
  A 
  shade 
  beneath 
  the 
  

   white 
  line,. 
  intensified 
  at 
  each 
  end 
  where 
  it 
  joins 
  the 
  white; 
  another, 
  along 
  the 
  poste- 
  

   rior 
  border, 
  narrow 
  at 
  apex 
  and 
  broadening 
  to 
  the 
  middle, 
  where 
  it 
  projects 
  along 
  the 
  

   middle 
  of 
  the 
  wing 
  above 
  the 
  white 
  line, 
  fading 
  away 
  toward 
  base, 
  and 
  a 
  fainter 
  shade 
  

   along 
  the 
  front 
  or 
  costal 
  edge, 
  intensifying 
  toward 
  apes. 
  The 
  species 
  is 
  one 
  of 
  th(^ 
  

   smallest 
  of 
  the 
  genus, 
  having 
  but 
  two-thirds 
  of 
  the 
  size 
  of 
  the 
  army-worm. 
  — 
  (Riley.) 
  

  

  The 
  Wiieat-Thrips, 
  iimo</ir(j)S 
  ir 
  itici 
  Yitch. 
  — 
  "Upon 
  the 
  heads 
  and 
  stalks 
  in 
  June 
  

   and 
  July, 
  exhausting 
  the 
  juices 
  of 
  the 
  kernels 
  and 
  rendering 
  them 
  dwarfish 
  and 
  shriv- 
  

   eled 
  ; 
  exceedingly 
  minute, 
  active, 
  long, 
  and 
  narrow 
  six- 
  legged 
  insects, 
  of 
  a 
  bright-yel- 
  

   low 
  or 
  of 
  a 
  shining-black 
  color." 
  — 
  (Fitch.) 
  

  

  Tbe 
  wheat-thrips 
  in 
  this 
  country 
  also 
  occurs 
  on 
  the 
  onion, 
  and 
  is 
  

   described 
  more 
  fully 
  under 
  tbe 
  head 
  of 
  onion-insects. 
  It 
  represents 
  the 
  

   Phl(cothri2)s 
  cenalium 
  of 
  Europe, 
  which 
  does, 
  at 
  times, 
  extensive 
  injury 
  to 
  

   the 
  wheat, 
  gnawing 
  and 
  puncturing 
  the 
  seed, 
  causing 
  it 
  to 
  shrink 
  and 
  

   become 
  what 
  the 
  farmers 
  call 
  "])ungled." 
  It 
  also 
  gnaws 
  the 
  young- 
  

   stalks 
  just 
  above 
  the 
  knots, 
  causing 
  the 
  ear 
  to 
  become 
  abortive^ 
  

   Another 
  species 
  common 
  on 
  wheat 
  in 
  New 
  York, 
  in 
  June, 
  is 
  the 
  Three- 
  

   banded 
  Thrips 
  {Coleothrips 
  trifasciata) 
  of 
  Fitch. 
  It 
  is 
  nearly 
  double 
  the 
  

   size 
  of 
  the 
  wheat-thrips, 
  being 
  0.07 
  inch 
  in 
  length, 
  and 
  is 
  black 
  ; 
  the 
  dark 
  

   wings 
  having 
  three 
  broad 
  white 
  bands 
  across 
  them, 
  while 
  the 
  antennae 
  

   arise 
  close 
  together, 
  "and 
  are 
  composed 
  of 
  only 
  five 
  principal 
  joints, 
  

   of 
  which 
  the 
  two 
  first 
  are 
  short, 
  and 
  a 
  third 
  thicker 
  than 
  the 
  others, 
  

   which 
  are 
  long 
  and 
  cylindrical, 
  the 
  last 
  one 
  gradually 
  tapering 
  to 
  a 
  slen- 
  

   der 
  point, 
  its 
  apical 
  portion 
  being 
  divided 
  into 
  small 
  indistinct 
  segments." 
  

  

  The 
  Wheat- 
  Worm, 
  Anguilhda 
  triiici 
  Bauer. 
  — 
  Filling 
  the 
  cavities 
  of 
  a 
  grain 
  of 
  wheat, 
  

   a 
  white 
  fibrous 
  substance, 
  formed 
  by 
  gluten 
  into 
  balls 
  of 
  a 
  silky 
  nature, 
  which 
  

   instantly 
  dissolve 
  in 
  water 
  and 
  exhibit 
  hundreds 
  of 
  minute 
  worms, 
  causing 
  the 
  dis- 
  

   ease 
  called 
  ''ear-cockle" 
  or 
  "purples." 
  

  

  Although 
  this 
  worm 
  has 
  not 
  yet 
  been 
  observed 
  in 
  America 
  so 
  far 
  as 
  

   I 
  am 
  aware, 
  it 
  is 
  not 
  improbable 
  that 
  this 
  disease 
  occurs 
  with 
  us, 
  though 
  

   not 
  yet 
  detected. 
  I 
  abstract 
  the 
  

   following 
  account, 
  often 
  word 
  for 
  

   word, 
  from 
  Curtis's 
  " 
  Farm 
  Insects." 
  

   Mr, 
  Curtis 
  took 
  his 
  description 
  of 
  

   the 
  worm 
  and 
  its 
  habits 
  from 
  

   Bauer's 
  notes 
  contained 
  in 
  Pro- 
  

   fessor 
  Henslow's 
  " 
  Report 
  on 
  the 
  

   Diseases 
  of 
  Wheat."* 
  

  

  " 
  The 
  eggs 
  are 
  taken 
  up 
  by 
  the 
  

   sap 
  from 
  the 
  infected 
  grain 
  which 
  

   may 
  have 
  been 
  planted, 
  and 
  hatch 
  

   in 
  the 
  stalk 
  as 
  well 
  as 
  in 
  the 
  seed. 
  

   The 
  largest 
  worms 
  are 
  -^ 
  inch 
  long 
  

  

  at 
  least, 
  of 
  a 
  yellowish-white 
  color, 
  

   and 
  not 
  so 
  transparent 
  as 
  the 
  

   young 
  worms. 
  Their 
  heads 
  are 
  

  

  Fig. 
  8. 
  — 
  Young 
  Wheat-Worm, 
  greatly 
  magni- 
  

   fied, 
  a, 
  section 
  of 
  a 
  grain 
  exhibiting 
  some 
  

   worms 
  and 
  multitudes 
  of 
  eggs, 
  magnified 
  ; 
  

   J) 
  an 
  egg 
  containing 
  a 
  worm 
  ready 
  to 
  hatch. 
  

   (From 
  Curtis, 
  after 
  Bauer.) 
  

  

  Journal 
  of 
  the 
  Royal 
  Agricultural 
  Society, 
  vol. 
  ii, 
  p. 
  19. 
  

  

  