﻿51 
  

  

  [libernating 
  jjjeneration 
  were 
  generally 
  perishing. 
  The 
  onlj' 
  exten- 
  

   sive 
  and 
  important 
  epidemic 
  of 
  contagious 
  disease 
  observed 
  was 
  that 
  

   nt 
  Mahomet, 
  where 
  the 
  green 
  muscardine 
  affected 
  for 
  a 
  time 
  in 
  July 
  

   fully 
  ninety 
  per 
  cent, 
  of 
  the 
  chinch-bugs 
  in 
  the 
  tield. 
  Observations 
  

   made 
  in 
  that 
  month 
  also 
  hint 
  at. 
  but 
  do 
  not 
  demonstrate, 
  the 
  presence 
  

   of 
  a 
  bacterial 
  malady. 
  

  

  There 
  is 
  no 
  doubt 
  of 
  the 
  destruction 
  of 
  a 
  large 
  number 
  of 
  young 
  

   chinch-bugs 
  by 
  violent 
  flooding 
  rains, 
  especially 
  such 
  as 
  may 
  wash 
  

   them 
  down 
  into 
  the 
  mud. 
  Kggs 
  are 
  i^robably 
  thus 
  destroyed 
  in 
  

   even 
  greater 
  numbers, 
  the 
  young 
  hatching 
  from 
  them 
  in 
  the 
  mud 
  be- 
  

   ing 
  unable 
  to 
  make 
  their 
  evScaj^e; 
  and 
  the 
  facts 
  justify 
  the 
  suspicion 
  

   that 
  very 
  wet 
  weather 
  tends 
  in 
  some 
  way 
  to 
  diminish 
  the 
  reproduc- 
  

   tive 
  activity 
  of 
  the 
  adults. 
  Death 
  by 
  immediate 
  drowning, 
  even 
  by 
  

   long-continued 
  rains, 
  was 
  not 
  clearly 
  proved 
  by 
  these 
  observations. 
  

   On 
  the 
  other 
  hand, 
  it 
  was 
  not 
  disproved, 
  but 
  it 
  is 
  rendered 
  prac- 
  

   tically 
  certain 
  by 
  laboratory 
  experiments 
  described 
  in 
  my 
  Eighth 
  

   Report 
  as 
  State 
  Entomologist, 
  that 
  for 
  1893 
  and 
  1894 
  (pages 
  178 
  and 
  

   183), 
  by 
  which 
  it 
  was 
  shown 
  that 
  newly 
  hatched 
  chinch-bugs 
  can- 
  

   not 
  withstand 
  submersion 
  much 
  over 
  two 
  hours 
  as 
  a 
  rule; 
  that 
  those 
  

   of 
  the 
  second 
  molt 
  may 
  begin 
  to 
  die 
  within 
  five 
  hours 
  and 
  will 
  prac- 
  

   tically 
  all 
  perish 
  within 
  nine; 
  that 
  even 
  pupte 
  may 
  be 
  drowned 
  by 
  

   eight 
  hours" 
  submersion, 
  others 
  living 
  for 
  at 
  least 
  thirteen 
  hours; 
  

   and 
  that 
  some 
  adults 
  at 
  least 
  will 
  be 
  killed 
  by 
  twelve 
  hours' 
  con- 
  

   tinuous 
  submersion, 
  although 
  some 
  may 
  survive 
  nearly 
  twenty-four. 
  

  

  Fuller 
  details 
  of 
  our 
  observations 
  and 
  experiments 
  are 
  herewith 
  

   given, 
  first 
  under 
  a 
  summary 
  statement 
  for 
  each 
  observing 
  station, 
  

   and, 
  following 
  this, 
  in 
  a 
  detailed 
  abstract 
  of 
  field 
  and 
  laboratory 
  

  

  notes. 
  

  

  SUMMARY 
  STATEMENT 
  FOR 
  EACH 
  OBSERVING 
  STATION. 
  

  

  At 
  Tamaroa 
  the 
  chinch-bugs 
  were 
  already 
  out 
  of 
  their 
  winter 
  quar- 
  

   ters 
  by 
  April 
  27, 
  and 
  concentrated 
  mainly 
  in 
  fields 
  of 
  wheat, 
  in 
  which 
  

   they 
  were 
  very 
  abundant. 
  The 
  ground 
  here 
  was 
  well 
  stocked 
  with 
  

   eggs, 
  but 
  few 
  or 
  no 
  young 
  had 
  yet 
  appeared. 
  The 
  common 
  fungus 
  

   of 
  white 
  muscardine 
  (Sporotrichum) 
  was 
  everywhere 
  present 
  in 
  

   small 
  quantity 
  on 
  chinch-bugs 
  and 
  other 
  dead 
  insects. 
  Repeated 
  

   heavy 
  rains 
  in 
  May 
  and 
  June 
  were 
  followed 
  by 
  some 
  increase 
  in 
  the 
  

   number 
  of 
  these 
  fungus-covered 
  chinch- 
  bugs, 
  and 
  green 
  muscardine 
  

   (Entomophthora) 
  also 
  ai)peared 
  among 
  them 
  in 
  a 
  small 
  way 
  early 
  in 
  

   June. 
  The 
  number 
  of 
  eggs 
  and 
  young 
  was 
  very 
  much 
  smaller 
  as 
  

   the 
  season 
  progressed 
  than 
  the 
  heavy 
  attack 
  upon 
  the 
  wheat 
  in 
  

   spring 
  gave 
  reason 
  to 
  expect. 
  Some 
  of 
  the 
  young 
  were 
  certainly 
  

   killed 
  directly 
  by 
  the 
  rain, 
  which 
  washed 
  them 
  off 
  their 
  food 
  plants 
  

   and 
  imbedded 
  them 
  in 
  the 
  mud, 
  and 
  doubtless 
  a 
  very 
  considerable 
  

   proportion 
  of 
  both 
  young 
  and 
  eggs 
  were 
  thus 
  effectually 
  disposed 
  of. 
  

   A 
  few 
  adults 
  of 
  the 
  hibernating 
  generation 
  were 
  still 
  alive 
  and 
  breed- 
  

   ing 
  May 
  28. 
  

  

  The 
  number 
  appearing 
  upon 
  the 
  outer 
  rows 
  of 
  corn 
  after 
  wheat 
  

   harvest 
  was 
  here 
  so 
  small 
  as 
  to 
  indicate 
  an 
  enormous 
  destruction 
  of 
  

   the 
  progeny 
  of 
  the 
  hibernating 
  generation, 
  or 
  a 
  very 
  general 
  diminu- 
  

  

  