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  CONTAGIOUS 
  DISEASES 
  OF 
  THE 
  CHINCH-BUG. 
  

  

  gish, 
  moving 
  slowly 
  along, 
  as 
  if 
  stiff 
  and 
  feeble, 
  the 
  abdomens 
  noticeably 
  distended 
  

   and 
  unusually 
  greenish 
  beneath. 
  

  

  Crushing 
  both 
  dead 
  and 
  living 
  examples, 
  and 
  slightly 
  diluting 
  the 
  fluids 
  with 
  dis- 
  

   tilled 
  water, 
  immense 
  numbers 
  of 
  bacteria 
  were 
  apparent, 
  moving 
  without 
  flagellar 
  

   action, 
  unmistakably 
  the 
  same 
  as 
  those 
  studied 
  in 
  1882. 
  Collected 
  in 
  a 
  film 
  on 
  a 
  

   cover 
  glass, 
  dried, 
  flamed, 
  stained 
  with 
  aniline 
  and 
  mounted 
  in 
  balsam, 
  these 
  bacte- 
  

   ria 
  had 
  the 
  appearance 
  of 
  a 
  short- 
  jointed 
  bacillus, 
  with 
  a 
  pale 
  center 
  which 
  did 
  not 
  

   take 
  the 
  stain. 
  If 
  the 
  fluids 
  were 
  not 
  much 
  pressed 
  or 
  agitated, 
  there 
  were 
  usually 
  

   visible 
  many 
  globular 
  masses 
  of 
  these 
  bacilli, 
  looking 
  like 
  free 
  nuclei, 
  but 
  readily 
  

   broken 
  up 
  by 
  repeated 
  pressure, 
  the 
  separate 
  individuals 
  swarming 
  everywhere. 
  

   Sometimes 
  careful 
  crushing 
  in 
  water 
  would 
  enable 
  one 
  to 
  trace 
  the 
  streams 
  of 
  escap- 
  

   ing 
  bacteria 
  to 
  a 
  portion 
  of 
  the 
  alimentary 
  canal 
  protruding 
  through 
  a 
  break 
  in 
  the 
  

   crust. 
  

  

  On 
  the 
  18th 
  of 
  September, 
  I 
  killed 
  carefully 
  and 
  at 
  once 
  dissected 
  a 
  pupa 
  from 
  

   Odin, 
  presenting 
  the 
  symptoms 
  of 
  disease. 
  First 
  crushing 
  on 
  the 
  slide 
  portions 
  of 
  

   the 
  fatty 
  bodies, 
  I 
  recognized 
  a 
  small 
  number 
  of 
  the 
  usual 
  bacilli, 
  but 
  when 
  I 
  isolated 
  

   portions 
  of 
  the 
  gastric 
  coeca 
  transferred 
  to 
  a 
  clean 
  slide, 
  and 
  crushed 
  carefully 
  in 
  

   place, 
  I 
  found 
  the 
  fluid 
  swarming 
  with 
  immense 
  numbers 
  of 
  bacilli; 
  saw 
  others 
  rap- 
  

   idly 
  escaping 
  in 
  streams 
  from 
  the 
  torn 
  tubes 
  or 
  dancing 
  about 
  with 
  them, 
  and 
  

   found 
  the 
  nuclei 
  of 
  the 
  epithelial 
  cells 
  seemingly 
  closely 
  packed 
  with 
  the 
  same 
  bac- 
  

   teria. 
  Curiously, 
  on 
  carefully 
  isolating 
  and 
  crushing 
  on 
  still 
  another 
  slide 
  the 
  an- 
  

   terior 
  part 
  of 
  the 
  alimentary 
  canal, 
  that 
  preceding 
  the 
  coeca, 
  I 
  could 
  not 
  find 
  a 
  

   single 
  microbe. 
  The 
  posterior 
  part 
  contained, 
  however, 
  a 
  moderate 
  number 
  demon- 
  

   strated 
  in 
  the 
  same 
  manner. 
  Another 
  specimen, 
  studied 
  by 
  the 
  same 
  methods, 
  

   contained 
  vast 
  numbers 
  of 
  the 
  characteristic 
  bacillus 
  in 
  the 
  coeca, 
  but 
  none 
  that 
  I 
  

   could 
  clearly 
  recognize 
  in 
  the 
  other 
  parts 
  of 
  the 
  alimentary 
  canal. 
  They 
  were 
  want- 
  

   ing 
  in 
  the 
  Malpighian 
  tubules. 
  

  

  Examples 
  collected 
  September 
  19, 
  in 
  corn 
  fields 
  at 
  Albion, 
  in 
  Edwards 
  county, 
  

   contained 
  sometimes 
  more 
  and 
  sometimes 
  fewer 
  of 
  these 
  bacteria, 
  and 
  occasionally 
  

   none; 
  others 
  from 
  Ashley, 
  obtained 
  at 
  the 
  same 
  time, 
  were 
  moderately 
  infested; 
  and 
  

   examples 
  from 
  Edgewood, 
  received 
  September 
  22, 
  contained 
  them, 
  if 
  at 
  all, 
  in 
  

   numbers 
  so 
  small 
  that 
  I 
  could 
  not 
  satisfy 
  myself 
  of 
  their 
  presence. 
  Specimens 
  from 
  

   Mascoutah, 
  sent 
  September 
  22, 
  contained 
  a 
  variable 
  number, 
  vast 
  quantities 
  oc- 
  

   curring 
  in 
  some 
  and 
  relatively 
  few 
  in 
  others. 
  Their 
  apparently 
  greater 
  number 
  in 
  

   pupas 
  than 
  in 
  imagos 
  was 
  possibly 
  due 
  to 
  the 
  greater 
  ease 
  and 
  thoroughness 
  with 
  

   which 
  the 
  relatively 
  soft 
  bodies 
  of 
  the 
  former 
  could 
  be 
  crushed 
  on 
  the 
  slide. 
  

  

  Bugs 
  received 
  from 
  Bond 
  county 
  October 
  3 
  were 
  similarly 
  examined, 
  and 
  found 
  

   in 
  similar 
  condition. 
  Of 
  three 
  pupa? 
  crushed, 
  the 
  first 
  contained 
  an 
  extraordinary 
  

   number, 
  the 
  second 
  a 
  scarcely 
  inferior 
  abundance, 
  and 
  the 
  third 
  only 
  a 
  moderate 
  

   quantity. 
  Cultures 
  made 
  from 
  the 
  first 
  of 
  the 
  above 
  were 
  completely 
  successful, 
  and 
  

   gave 
  conclusive 
  evidence 
  as 
  to 
  the 
  character 
  and 
  life-history 
  of 
  this 
  bacillus. 
  

  

  On 
  the 
  other 
  hand, 
  and 
  finally, 
  three 
  adults 
  collected 
  at 
  Golconda, 
  on 
  the 
  Ohio 
  

   river, 
  October 
  4, 
  contained 
  no 
  bacteria 
  that 
  I 
  could 
  recognize. 
  If 
  present 
  at 
  all, 
  

   the 
  number 
  was 
  certainly 
  very 
  small. 
  

  

  From 
  the 
  foregoing 
  it 
  is 
  apparent 
  that 
  this 
  bacillus 
  was 
  unequally 
  but 
  abundantly 
  

   distributed 
  throughout 
  the 
  region 
  where 
  the 
  chinch-bug 
  had 
  reached 
  its 
  culminating 
  

   point 
  last 
  year, 
  but, 
  on 
  the 
  other 
  hand, 
  its 
  absence 
  in 
  specimens 
  from 
  Pope 
  county, 
  

   where 
  the 
  insect 
  was 
  more 
  destructive 
  this 
  year 
  than 
  last, 
  is 
  of 
  special 
  interest 
  and 
  

   significance. 
  

  

  The 
  numerous 
  bacterial 
  cultures 
  made 
  from 
  these 
  insects, 
  completely 
  successful 
  

   in 
  both 
  fluid 
  and 
  solid 
  media, 
  may 
  best 
  be 
  reported 
  elsewhere. 
  It 
  is 
  sufficient 
  to 
  say 
  

   that 
  they 
  showed 
  this 
  chinch-bug 
  microbe 
  to 
  be 
  a 
  bacillus, 
  flagellate 
  in 
  fluid 
  cultures, 
  

  

  