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  is 
  small, 
  for 
  food 
  is 
  scarce 
  in 
  the 
  latter 
  part 
  of 
  the 
  summer. 
  This 
  

   insect 
  winters 
  in 
  bunch 
  grass 
  (Aiidropogon 
  scoparius, 
  Michx.), 
  big 
  blue 
  

   stem 
  {A. 
  furcatus, 
  MuhL), 
  false 
  redtop 
  {Triplasis 
  purpurea, 
  Walt.) 
  and 
  

   similar 
  bunch-forming 
  grasses. 
  With 
  the 
  advent 
  of 
  warm 
  weather 
  

   the 
  chinch 
  bugs 
  begin 
  to 
  emerge 
  and 
  leave 
  their 
  winter 
  quarters 
  for 
  

   wheat 
  and 
  other 
  small 
  grains. 
  Here 
  the 
  young 
  are 
  produced 
  and 
  

   reach 
  maturity 
  shortly 
  after 
  harvest 
  time. 
  With 
  the 
  failure 
  of 
  food 
  in 
  

   the 
  small 
  grain 
  field 
  the 
  bugs 
  migrate 
  into 
  adjacent 
  fields 
  of 
  corn 
  and 
  

   sorghum. 
  Here 
  the 
  young 
  produced 
  reach 
  maturity 
  in 
  the 
  autumn 
  

   and 
  estabhsh 
  winter 
  quarters 
  in 
  the 
  grass. 
  Among 
  the 
  natural 
  checks 
  

   to 
  the 
  chinch 
  bug, 
  cUmate 
  is 
  probably 
  the 
  most 
  important, 
  temperature 
  

   and 
  moisture 
  having 
  been 
  shown 
  to 
  exercise 
  a 
  great 
  influence 
  on 
  the 
  

   insect. 
  The 
  low 
  temperatures 
  of 
  mnter 
  diminish 
  the 
  metabohsm 
  and 
  

   lengthen 
  the 
  life 
  of 
  the 
  bug. 
  Specimens 
  have 
  been 
  frozen 
  in 
  ice 
  and 
  

   yet 
  recovered 
  when 
  released. 
  Subjected 
  to 
  a 
  constant 
  temperature 
  

   of 
  90°F. 
  with 
  a 
  humid 
  atmosphere 
  the 
  chinch 
  bugs 
  perish 
  too 
  quickly 
  

   to 
  effect 
  reproduction. 
  They 
  thrive 
  in 
  dry 
  seasons, 
  but 
  die 
  in 
  wet 
  ones, 
  

   60 
  per 
  cent, 
  relative 
  humidity 
  being 
  considered 
  from 
  experiments 
  to 
  

   be 
  most 
  favourable 
  at 
  a 
  temperature 
  of 
  70° 
  F. 
  AVet 
  weather 
  destroys 
  

   the 
  bugs 
  directly 
  and 
  indirectly 
  ; 
  directly 
  by 
  burying 
  the 
  young 
  and 
  the 
  

   eggs 
  ; 
  indirectly 
  by 
  weakening 
  the 
  bug 
  and 
  rendering 
  it 
  more 
  susceptible 
  

   of 
  disease 
  and 
  by 
  encouraging 
  the 
  growth 
  of 
  its 
  fungous 
  parasite, 
  

   Sporotrichum 
  globuliferum, 
  Speg. 
  This 
  fungus 
  and 
  Entomophthora 
  

   (Empusa) 
  aphidis, 
  Hoffman, 
  stand 
  pre-eminent 
  among 
  the 
  enemies 
  

   of 
  the 
  chinch 
  bug. 
  Much 
  work 
  has 
  been 
  done 
  on 
  these 
  fungi, 
  but 
  all 
  

   the 
  really 
  careful 
  experiments 
  agree 
  with 
  the 
  author's 
  results 
  

   in 
  showing 
  that 
  it 
  is 
  not 
  possible 
  by 
  artificial 
  distribution 
  of 
  the 
  fungus 
  

   to 
  hasten 
  materially 
  the 
  progress 
  of 
  the 
  disease. 
  On 
  the 
  whole 
  these 
  

   parasitic 
  fungi 
  are 
  well 
  distributed 
  throughout 
  that 
  part 
  of 
  the 
  United 
  

   States 
  subject 
  to 
  chinch 
  bug 
  outbreaks 
  and 
  cause 
  great 
  epidemics 
  when 
  

   temperature 
  and 
  moisture 
  become 
  favourable. 
  An 
  average 
  tempera- 
  

   ture 
  of 
  75° 
  F. 
  and 
  a 
  moisture 
  close 
  to 
  saturation 
  are 
  most 
  favourable 
  

   to 
  the 
  activity 
  of 
  S. 
  globuliferum. 
  Among 
  animals 
  the 
  chinch 
  bug 
  

   has 
  few 
  natural 
  enemies. 
  No 
  internal 
  parasite 
  is 
  known 
  to 
  attack 
  it. 
  

   The 
  lady-birds, 
  Megilla 
  maculata, 
  de 
  G., 
  CoccineUa 
  sanguinea, 
  L., 
  

   Hippodamia 
  convergens, 
  Guer., 
  H. 
  glaeialis, 
  F., 
  H. 
  13-punctata, 
  L., 
  

   and 
  two 
  species 
  of 
  Scymnus, 
  and 
  Chrysopa 
  plorabunda, 
  Fitch, 
  have 
  been 
  

   recorded 
  as 
  its 
  foes. 
  The 
  flower 
  bug 
  (Triphleps 
  insidiosus, 
  Say) 
  and 
  

   Milyas 
  cinctus, 
  F., 
  have 
  been 
  knowTi 
  to 
  destroy 
  the 
  pest. 
  Twice 
  the 
  

   false 
  chinch 
  bug 
  (Nysius 
  angustatus, 
  Uhl.) 
  has 
  been 
  observed 
  feeding 
  

   on 
  the 
  nymphs 
  in 
  the 
  field 
  ; 
  and 
  Harpalus 
  compar, 
  Lee, 
  Euarthrus 
  

   sodalis, 
  Lee, 
  and 
  Anisodactylus 
  harpaloides, 
  Laf., 
  have 
  been 
  seen 
  

   feeding 
  on 
  bugs 
  of 
  all 
  ages. 
  A 
  centipede 
  and 
  Gryllus 
  sp. 
  feed 
  on 
  adults 
  ; 
  

   the 
  ant, 
  Solenopsis 
  molesta, 
  Say, 
  was 
  observed 
  carrying 
  off 
  chinch 
  bug 
  

   eggs, 
  and 
  Monomorium 
  minimum 
  carrying 
  bugs 
  of 
  all 
  sizes. 
  Among 
  

   birds 
  the 
  chief 
  enemies 
  are 
  the 
  quail, 
  prairie 
  chicken, 
  red- 
  winged 
  black- 
  

   bird, 
  catbird, 
  brown 
  thrush, 
  meadow-lark, 
  house 
  wren, 
  tree 
  swallow, 
  

   homed 
  lark 
  and 
  fiicker. 
  These 
  are 
  not 
  efficient 
  enemies. 
  In 
  a 
  single 
  

   year 
  the 
  chinch 
  bug 
  damages 
  crops 
  worth 
  millions 
  of 
  dollars 
  and 
  may 
  

   greatly 
  reduce 
  the 
  wheat 
  and 
  absolutely 
  destroy 
  the 
  corn 
  and 
  sorghums 
  

   of 
  the 
  individual 
  farmer. 
  As 
  the 
  result 
  of 
  many 
  tests 
  it 
  has 
  been 
  found 
  

   that 
  twice 
  during 
  the 
  year 
  the 
  chinch 
  bug 
  may 
  be 
  destroyed 
  — 
  while 
  

   passing 
  from 
  wheat 
  and 
  other 
  small 
  grains 
  into 
  adjacent 
  fields 
  of 
  corn 
  

  

  