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  CONTAGIOUS 
  DISEASES 
  OF 
  THE 
  CHINCH-BUG. 
  

  

  ceeded 
  in 
  getting 
  the 
  fungus 
  established 
  at 
  two 
  widely-located 
  points 
  in 
  Indiana, 
  

   and 
  do 
  not 
  consider 
  it 
  at 
  all 
  difficult 
  to 
  introduce 
  in 
  localities 
  where 
  chinch-bugs 
  are 
  

   abundant, 
  provided 
  the 
  weather 
  is 
  favorable. 
  But 
  if 
  it 
  is 
  ever 
  utilized 
  by 
  the 
  farmer, 
  

   which 
  seems 
  to 
  me 
  to 
  be 
  at 
  present 
  a 
  matter 
  of 
  considerable 
  doubt, 
  it 
  will 
  be 
  only 
  

   after 
  the 
  pest 
  has 
  become 
  very 
  abundant, 
  during 
  the 
  time 
  between 
  the 
  first 
  larval 
  and 
  

   adult 
  stages, 
  and 
  in 
  a 
  wet 
  time. 
  After 
  the 
  Entomophthora 
  has 
  been 
  introduced 
  into 
  

   a 
  certain 
  field, 
  it 
  will 
  become 
  diffused 
  only 
  in 
  proportion 
  as 
  the 
  bugs 
  travel 
  about 
  

   and 
  healthy 
  bugs 
  come 
  in 
  contact 
  with 
  spores 
  from 
  those 
  which 
  have 
  died 
  from 
  the 
  

   disease. 
  This 
  will 
  not 
  be 
  very 
  great 
  until 
  the 
  pupal 
  stage 
  is 
  reached. 
  

  

  The 
  larvae 
  of 
  chinch-bugs 
  seem 
  to 
  in 
  some 
  way 
  understand 
  that 
  while 
  moulting 
  

   they 
  will 
  be 
  well-nigh 
  helpless, 
  and 
  hence 
  hide 
  themselves 
  away 
  in 
  vast 
  numbers 
  in 
  

   secluded 
  places. 
  Under 
  such 
  conditions, 
  the 
  spores 
  thrown 
  from 
  diseased 
  bugs 
  would 
  

   reach 
  a 
  larger 
  number 
  of 
  their 
  fellows. 
  I 
  have 
  found 
  adults 
  but 
  recently 
  moulted 
  

   affected 
  by 
  the 
  Entomophthora. 
  After 
  the 
  bugs 
  acquire 
  wings 
  and 
  scatter 
  themselves 
  

   over 
  the 
  country, 
  the 
  liability 
  to 
  contagion 
  will 
  be 
  again 
  reduced, 
  unless 
  in 
  case 
  of 
  

   very 
  severe 
  invasions, 
  where, 
  from 
  force 
  of 
  numbers, 
  congregating 
  on 
  or 
  about 
  food 
  

   plants 
  becomes 
  a 
  necessity. 
  Hence, 
  the 
  introduction 
  of 
  the 
  fungus 
  among 
  larvae 
  will 
  

   at 
  first 
  proceed 
  but 
  slowly, 
  and 
  only 
  in 
  extreme 
  cases 
  and 
  under 
  favorable 
  conditions 
  

   can 
  it 
  be 
  expected 
  to 
  proceed 
  much 
  more 
  raipdly 
  among 
  adult 
  bugs. 
  In 
  short, 
  the 
  

   only 
  way 
  that 
  this 
  fungoid 
  disease 
  seems 
  capable 
  of 
  being 
  employed 
  in 
  agriculture 
  

   is, 
  by 
  the 
  establishment 
  of 
  some 
  central 
  propagating 
  station 
  to 
  which 
  farmers 
  can 
  

   apply 
  and 
  receive 
  an 
  abundant 
  supply 
  of 
  infected 
  bugs 
  on 
  short 
  notice. 
  By 
  this 
  

   means, 
  they 
  could 
  take 
  advantage 
  of 
  a 
  rainy 
  period 
  of 
  a 
  week 
  or 
  10 
  days, 
  and, 
  if 
  they 
  

   can 
  contrive 
  by 
  sowing 
  plats 
  of 
  millet 
  and 
  Hungarian 
  to 
  mass 
  the 
  bugs 
  in 
  certain 
  

   localities 
  about 
  their 
  fields, 
  they 
  might 
  accomplish 
  something 
  towards 
  warding 
  off 
  

   an 
  invasion. 
  But 
  the 
  possibility 
  of 
  overcoming 
  an 
  invasion 
  after 
  it 
  is 
  fully 
  under 
  

   way, 
  (as 
  is 
  almost 
  sure 
  to 
  be 
  the 
  case 
  during 
  a 
  dry 
  season,) 
  it 
  must 
  be 
  confessed 
  

   is 
  not 
  very 
  encouraging. 
  My 
  failure, 
  after 
  repeated 
  experiments, 
  to 
  produce 
  this 
  

   Entomophthora 
  in 
  the 
  vicinity 
  of 
  La 
  Fayette 
  without 
  the 
  importation 
  of 
  germs 
  is 
  de- 
  

   cidedly 
  against 
  the 
  theory 
  that 
  might 
  be 
  advanced, 
  that 
  the 
  northeastern 
  portion 
  of 
  

   the 
  State 
  was 
  kept 
  free 
  of 
  destructive 
  invasions 
  by 
  reason 
  of 
  this 
  disease 
  brought 
  

   about 
  by 
  wet 
  weather. 
  There 
  is 
  as 
  yet 
  no 
  reason 
  to 
  believe 
  that 
  the 
  disease 
  has 
  ever 
  

   existed 
  in 
  that 
  section 
  of 
  the 
  State. 
  

  

  Before 
  leaving 
  the 
  subject 
  it 
  will 
  be 
  proper 
  to 
  state 
  that 
  in 
  my 
  experiments 
  a 
  

   larva 
  of 
  Crysopa 
  was 
  introduced 
  by 
  accident 
  and 
  passed 
  through 
  the 
  larval 
  stage, 
  

   feeding 
  continually 
  on 
  bugs 
  dying 
  from 
  the 
  effects 
  of 
  the 
  fungus. 
  

  

  In 
  the 
  November, 
  1889, 
  issue 
  of 
  Insect 
  Life, 
  edited 
  by 
  Dr. 
  C. 
  V. 
  Riley 
  and 
  

   his 
  assistants, 
  editorial 
  mention 
  of 
  my 
  own 
  and 
  Doctor 
  Lugger's 
  experiments 
  

   is 
  made. 
  Professor 
  Webster's 
  report 
  had 
  not 
  at 
  this 
  time 
  appeared. 
  The 
  in- 
  

   formation 
  concerning 
  my 
  work 
  was 
  obtained 
  from 
  an 
  article 
  in 
  the 
  Lawrence 
  

   Daily 
  Journal 
  of 
  October 
  2, 
  1889, 
  the 
  article 
  being 
  in 
  no 
  way 
  an 
  attempt 
  at 
  

   a 
  detailed 
  account 
  of 
  my 
  work, 
  being 
  written 
  by 
  a 
  reporter 
  of 
  the 
  paper. 
  

   The 
  notice 
  in 
  Insect 
  Life 
  presumably 
  reflects 
  Doctor 
  Riley's 
  views 
  upon 
  the 
  

   matter. 
  From 
  it 
  I 
  quote 
  as 
  follows 
  : 
  

  

  Ever 
  since 
  Prof. 
  0. 
  Lugger 
  published 
  his 
  apparently 
  favorable 
  results 
  in 
  the 
  same 
  

   direction, 
  something 
  more 
  than 
  a 
  year 
  ago, 
  we 
  have 
  watched 
  the 
  accounts 
  of 
  subse- 
  

   quent 
  attempts, 
  and 
  endeavored 
  to 
  ascertain 
  whether 
  any 
  thoroughly 
  scientific 
  evi- 
  

   dence 
  of 
  the 
  spread 
  of 
  the 
  disease 
  has 
  been 
  established. 
  The 
  matter 
  is 
  of 
  sufficient 
  

   importance 
  to 
  require 
  the 
  most 
  careful 
  weighing 
  of 
  the 
  evidence, 
  as 
  the 
  apparent 
  

   evidence 
  is 
  so 
  easily 
  misconstrued, 
  and 
  the 
  danger 
  of 
  unjustified 
  statement 
  and 
  as- 
  

  

  