﻿49 
  

  

  tory 
  experiments 
  were 
  made 
  chiefly 
  by 
  Mr. 
  Snow 
  and 
  myself. 
  Not- 
  

   withstanding 
  the 
  number 
  of 
  persons 
  engaged 
  upon 
  this 
  work, 
  its 
  

   unity 
  and 
  uniformity 
  througliout 
  the 
  soason 
  were 
  very 
  well 
  main- 
  

   tained 
  by 
  precise 
  directions 
  to 
  each 
  observer 
  and 
  by 
  a 
  systematic 
  

   supervision 
  of 
  its 
  progress. 
  

  

  The 
  regular 
  observations 
  and 
  collections, 
  beginning 
  April 
  i-l 
  and 
  

   ceasing 
  October 
  5, 
  were 
  distributed 
  over 
  selected 
  points 
  in 
  five 
  

   counties, 
  all 
  on 
  the 
  line 
  of 
  the 
  Illinois 
  Central 
  railroad 
  from 
  Cham- 
  

   paign 
  southward; 
  and 
  the 
  same 
  points 
  — 
  in 
  most 
  cases 
  the 
  same 
  fields 
  

   — 
  ^were 
  visited 
  on 
  each 
  trip. 
  These 
  stations 
  of 
  observation 
  were 
  

   Tamaroa, 
  in 
  Perry 
  county: 
  Odin, 
  in 
  Marion 
  county; 
  Edgewood, 
  in 
  

   Effingham 
  county; 
  Mattoon, 
  in 
  Coles 
  county; 
  and 
  Url)ana 
  and 
  Ma- 
  

   homet, 
  in 
  Champaign 
  county, 
  the 
  extreme 
  stations 
  of 
  the 
  series 
  

   being 
  about 
  one 
  hundred 
  and 
  fifty 
  miles 
  apart 
  from 
  north 
  to 
  south. 
  

   This 
  selection 
  proved 
  fortunate, 
  on 
  the 
  whole, 
  as 
  the 
  different 
  sta- 
  

   tions 
  resembled 
  each 
  other 
  closely 
  enough 
  to 
  make 
  it 
  possible 
  to 
  

   compare 
  results 
  to 
  advantage, 
  and 
  yet 
  each 
  had 
  a 
  distinctive 
  char- 
  

   acter 
  of 
  some 
  importance 
  to 
  our 
  purposes. 
  Tamaroa, 
  Odin, 
  and 
  Edge- 
  

   wood 
  are 
  all 
  in 
  the 
  agricultural 
  region 
  commonly 
  known 
  as 
  Southern 
  

   Illinois, 
  but 
  differ 
  considerably 
  in 
  soil 
  and 
  surroundings. 
  The 
  

   country 
  about 
  each 
  was 
  originally 
  prairie, 
  with 
  a 
  light-colored 
  soil 
  

   containing 
  much 
  clay 
  and 
  comparatively 
  little 
  vegetable 
  mold, 
  and 
  

   winter 
  wheat 
  is 
  a 
  leading 
  crop. 
  Mattoon 
  and 
  Urbana 
  a 
  "e 
  in 
  the 
  

   black 
  paririe 
  region 
  of 
  Central 
  Illinois, 
  and 
  little 
  wheat 
  and 
  much 
  

   corn 
  are 
  raised 
  in 
  their 
  vicinity; 
  while 
  Mahomet, 
  although 
  in 
  Cham- 
  

   paign 
  county, 
  is 
  in 
  a 
  district 
  of 
  clay 
  soils, 
  originally 
  woodland, 
  near 
  

   the 
  Sangamon 
  River, 
  where 
  winter 
  wheat 
  is 
  much 
  raised. 
  At 
  the 
  

   four 
  wheat-growing 
  points, 
  the 
  chiiich-bug 
  was 
  very 
  much 
  more 
  

   abundant 
  than 
  at 
  the 
  other 
  two, 
  and 
  in 
  all 
  it 
  was 
  almost 
  completely 
  

   concentrated 
  in 
  early 
  spring 
  in 
  fields 
  of 
  glowing 
  wheat 
  and 
  rye. 
  

  

  The 
  weather 
  of 
  the 
  season 
  was 
  rather 
  unusually 
  wet 
  throughout 
  

   the 
  whole 
  district, 
  and 
  in 
  very 
  marked 
  contrast 
  to 
  the 
  extreme 
  drouth 
  

   of 
  the 
  years 
  just 
  preceding; 
  but 
  the 
  rains 
  fell 
  in 
  showers 
  and 
  in 
  

   rather 
  violent 
  storms 
  of 
  comparatively 
  short 
  period, 
  sometimes 
  with 
  

   intervals 
  of 
  considerable 
  drouth 
  between. 
  For 
  detailed 
  acc-ounts 
  of 
  

   the 
  rainfall 
  and 
  temperature 
  at 
  the 
  points 
  visited 
  which 
  are 
  em- 
  

   bodied 
  in 
  this 
  paper. 
  I 
  am 
  indebted 
  to 
  Mr. 
  Charles 
  E. 
  Linney. 
  

   Observer 
  and 
  Section 
  Director 
  of 
  the 
  Illinois 
  Section 
  of 
  the 
  Climate 
  

   and 
  Crop 
  Service 
  of 
  the 
  Weather 
  Bureau 
  of 
  the 
  L'nited 
  States 
  De- 
  

   partment 
  of 
  Agriculture. 
  

  

  The 
  field 
  observers 
  were 
  instructed 
  to 
  search 
  the 
  selected 
  fields 
  

   carefully 
  on 
  each 
  trip, 
  and 
  to 
  make 
  full 
  notes 
  on 
  the 
  weather 
  at 
  the 
  

   time; 
  on 
  the 
  number 
  and 
  distribution 
  of 
  the 
  bugs; 
  on 
  the 
  relative 
  

   number 
  in 
  each 
  age 
  or 
  stage: 
  on 
  evidences 
  of 
  contagious 
  diseases 
  in 
  

   the 
  fields 
  and 
  on 
  the 
  ages 
  of 
  the 
  bugs 
  principally 
  affected 
  by 
  them 
  ; 
  on 
  

   the 
  direct 
  action 
  of 
  weather, 
  and 
  particularly 
  of 
  rain, 
  in 
  the 
  destruc- 
  

   tion 
  of 
  bugs, 
  young 
  or 
  old; 
  and 
  on 
  the 
  comparative 
  numbers 
  of 
  the 
  

   various 
  ages 
  as 
  observed 
  on 
  successive 
  trips 
  to 
  the 
  same 
  place 
  They 
  

   were 
  also 
  expected 
  to 
  bring 
  to 
  the 
  laboratory 
  collections 
  of 
  dead 
  and 
  

  

  -4 
  

  

  