﻿OBSERVATIONS 
  AND 
  EXPERIMENTS 
  OF 
  1891 
  

  

  I. 
  -GENERAL 
  NOTES 
  AND 
  RESULTS. 
  

  

  The 
  experimental 
  work 
  with 
  chinch-bug 
  infection 
  for 
  the 
  year 
  1891 
  began 
  

   on 
  March 
  23. 
  On 
  this 
  date 
  a 
  lot 
  of 
  live, 
  healthy 
  chinch-bugs, 
  from 
  a 
  field 
  

   in 
  Southern 
  Kansas, 
  was 
  introduced 
  into 
  the 
  infection 
  jars 
  for 
  the 
  purpose 
  of 
  

   testing 
  their 
  condition. 
  Infection 
  had 
  been 
  carried 
  alive 
  through 
  the 
  two 
  

   preceding 
  winters 
  in 
  the 
  laboratory, 
  and 
  it 
  was 
  believed 
  that 
  the 
  third 
  winter 
  

   would 
  prove 
  to 
  be 
  no 
  exception. 
  It 
  was, 
  therefore, 
  with 
  great 
  satisfaction 
  

   that 
  I 
  observed, 
  in 
  a 
  few 
  days 
  after 
  the 
  date 
  above 
  mentioned, 
  that 
  the 
  healthy 
  

   chinch-bugs 
  introduced 
  in 
  the 
  infection 
  cages 
  began 
  to 
  sicken, 
  and 
  in 
  a 
  few 
  

   days 
  more 
  a 
  great 
  majority 
  of 
  them 
  were 
  dead, 
  while 
  the 
  portion 
  of 
  the 
  same 
  

   lot 
  of 
  healthy 
  bugs 
  which 
  had 
  been 
  placed 
  in 
  check 
  jars, 
  under 
  the 
  same 
  con- 
  

   ditions 
  except 
  as 
  to 
  exposure, 
  remained 
  in 
  a 
  condition 
  of 
  vigorous 
  health. 
  It 
  

   was 
  observed, 
  however, 
  that 
  when 
  the 
  laboratory 
  temperature 
  was 
  lowered, 
  a 
  

   longer 
  time 
  was 
  required 
  for 
  the 
  fatal 
  result. 
  

  

  From 
  the 
  fact 
  that 
  the 
  year 
  1890 
  had 
  been 
  a 
  dry 
  year, 
  and 
  in 
  many 
  parts 
  

   of 
  the 
  State 
  a 
  year 
  of 
  serious 
  drouth, 
  the 
  bacterial 
  infection 
  had 
  predomi- 
  

   nated 
  in 
  both 
  field 
  and 
  laboratory 
  experiments. 
  The 
  spring 
  of 
  1891, 
  there- 
  

   fore, 
  found 
  our 
  laboratory 
  provided 
  chiefly 
  with 
  bacterial 
  infection. 
  I 
  had 
  

   not, 
  up 
  to 
  this 
  time, 
  enjoyed 
  an 
  opportunity 
  of 
  experimenting 
  with 
  either 
  the 
  

   bacterial 
  or 
  fungus 
  infections 
  in 
  the 
  early 
  part 
  of 
  the 
  season. 
  The 
  first 
  field 
  

   experiments 
  in 
  1889 
  and 
  1890 
  were 
  not 
  made 
  until 
  after 
  the 
  middle 
  of 
  June. 
  

   It 
  was, 
  therefore, 
  very 
  problematical 
  whether 
  the 
  bacterial 
  infection 
  could 
  be 
  

   successfully 
  used 
  in 
  the 
  spring 
  months. 
  The 
  first 
  applications 
  for 
  infection 
  

   by 
  farmers 
  were 
  made 
  in 
  the 
  last 
  week 
  of 
  April. 
  The 
  infection 
  desired 
  by 
  

   these 
  applicants 
  was 
  for 
  use 
  in 
  wheat 
  fields, 
  and 
  up 
  to 
  this 
  time 
  no 
  experi- 
  

   ments 
  had 
  been 
  made 
  for 
  the 
  introduction 
  of 
  infection 
  in 
  wheat 
  fields. 
  It 
  

   was 
  found 
  that 
  the 
  bacterial 
  infection 
  was 
  not 
  well 
  adapted 
  to 
  the 
  destruc- 
  

   tion 
  of 
  chinch-bugs 
  in 
  the 
  field 
  in 
  the 
  months 
  of 
  April 
  and 
  May, 
  when 
  the 
  

   nights 
  were 
  cool 
  and 
  sometimes 
  frosty, 
  and 
  the 
  atmosphere 
  was 
  in 
  general 
  

   moist 
  on 
  account 
  of 
  abundant 
  rainfall. 
  I 
  found, 
  however, 
  that 
  the 
  compara- 
  

   tively 
  few 
  experiments 
  in 
  the 
  field 
  with 
  the 
  white-fungus 
  infection 
  (Sporo- 
  

   trichum) 
  in 
  April 
  and 
  May 
  were 
  almost 
  without 
  exception 
  successful, 
  resulting 
  

   in 
  the 
  general 
  destruction 
  of 
  the 
  chinch-bugs 
  in 
  the 
  wheat 
  fields. 
  

  

  Early 
  in 
  May 
  a 
  very 
  serious 
  difficulty 
  threatened 
  disaster 
  to 
  the 
  work 
  of 
  

   the 
  Station. 
  The 
  demand 
  for 
  infection 
  from 
  the 
  farmers 
  was 
  so 
  great 
  that 
  it 
  

   became 
  impossible 
  to 
  furnish 
  an 
  adequate 
  supply 
  with 
  the 
  means 
  for 
  the 
  

   propagation 
  of 
  infection 
  which 
  were 
  then 
  at 
  my 
  command. 
  The 
  infection 
  

   jars 
  at 
  that 
  time 
  were 
  of 
  small 
  size, 
  consisting 
  of 
  ordinary 
  jelly 
  glasses 
  with 
  

  

  (13) 
  

  

  