﻿112 
  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  As 
  this 
  table 
  was 
  intended 
  only 
  to 
  illustrate 
  the 
  chapter 
  on 
  chronology? 
  

   it 
  does 
  not 
  indicate 
  the 
  years 
  of 
  invasion 
  of 
  the 
  temporary 
  region. 
  We 
  

   therefore 
  call 
  attention 
  to 
  the 
  fact 
  that 
  the 
  years 
  of 
  great 
  locust 
  invasions 
  

   of 
  these 
  regions, 
  to 
  which 
  we 
  shall 
  chiefly 
  limit 
  the 
  present 
  discussion 
  7 
  

   were 
  1876, 
  1874, 
  and 
  1866. 
  The 
  year 
  1864 
  was 
  also 
  marked 
  by 
  the 
  ap- 
  

   pearance 
  of 
  numerous 
  invading 
  swarms 
  in 
  the 
  northwest, 
  but 
  the 
  locust 
  

   distribution 
  was 
  nothing 
  like 
  so 
  general 
  over 
  the 
  west 
  as 
  in 
  1866. 
  Accord- 
  

   ing 
  to 
  Mr. 
  Alexander 
  Taylor, 
  1855 
  was 
  also 
  a 
  noted 
  locust 
  year, 
  especially 
  

   in 
  the 
  intermontane 
  area, 
  on 
  the 
  Pacific 
  slope, 
  and 
  in 
  Mexico 
  ; 
  but 
  he 
  

   speaks 
  also 
  of 
  them 
  as 
  abundant 
  in 
  that 
  and 
  the 
  following 
  year 
  in 
  

   Nebraska, 
  Kansas, 
  and 
  Minnesota 
  Territories. 
  As 
  the 
  meteorological 
  

   records 
  that 
  reach 
  back 
  as 
  far 
  as 
  1855 
  are 
  too 
  meager 
  to 
  be 
  of 
  any 
  real 
  

   value, 
  we 
  shall 
  of 
  necessity 
  confine 
  our 
  investigations 
  to 
  the 
  period 
  

   embracing 
  1864, 
  1866, 
  1874, 
  and 
  1876. 
  

  

  The 
  following 
  table 
  of 
  rainfall 
  for 
  the 
  years 
  1860-1866, 
  at 
  the 
  stations 
  

   named 
  is 
  taken 
  chiefly 
  from 
  Schott's 
  Table 
  of 
  Eatios. 
  205 
  The 
  figures, 
  

   except 
  in 
  the 
  bottom 
  line, 
  are 
  the 
  ratios 
  of 
  the 
  rainfall 
  in 
  the 
  different 
  

   years 
  mentioned, 
  to 
  the 
  mean 
  annual 
  rainfall 
  of 
  the 
  station 
  named 
  at 
  

   the 
  head 
  of 
  the 
  column. 
  The 
  bottom 
  line 
  shows 
  the 
  mean 
  rainfall 
  in 
  

   inches 
  at 
  the 
  different 
  stations. 
  A 
  few 
  omissions 
  in 
  Schottfs 
  table 
  have 
  

   been 
  filled 
  out 
  from 
  the 
  record 
  in 
  the 
  Eeports 
  of 
  the 
  Agricultural 
  Depart- 
  

   ment: 
  

  

  Table 
  I. 
  — 
  Eatios 
  of 
  rainfall 
  for 
  the 
  years 
  1860-1868. 
  

  

  

  

  

  

  

  

  

  to 
  

  

  

  i 
  

  

  © 
  

   3 
  

  

  

  a 
  

  

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  Year. 
  

  

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  1 
  

  

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  • 
  

  

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   a 
  

  

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  . 
  

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  to 
  

  

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  ■s 
  

  

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  t< 
  

  

  

  ?, 
  

  

  '£ 
  

  

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  T3 
  

  

  > 
  

  

  

  Ph 
  

  

  Ph 
  

  

  N 
  

  

  p 
  

  

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  zo 
  

  

  fr 
  

  

  to 
  

  

  to 
  

  

  to 
  

  

  s 
  

  

  < 
  

  

  I860 
  

  

  1.22 
  

   1.29 
  

  

  .66 
  

   .90 
  

  

  .77 
  

   .74 
  

  

  .80 
  

   1.15 
  

  

  i'66" 
  

  

  .71 
  

   .90 
  

  

  .61 
  

   .86 
  

  

  .56 
  

   1.34 
  

  

  1.08 
  

   1.35 
  

  

  .07 
  

   .77 
  

  

  .68 
  

   .92 
  

  

  .78 
  

  

  1861 
  

  

  ].02 
  

  

  1862 
  

  

  .57 
  

  

  1.17 
  

  

  .89 
  

  

  1.05 
  

  

  1.24 
  

  

  1.04 
  

  

  .93 
  

  

  .86 
  

  

  .66 
  

  

  .87 
  

  

  1.13 
  

  

  .95 
  

  

  1863 
  

  

  .69 
  

  

  .73 
  

  

  .72 
  

  

  1.01 
  

  

  .88* 
  

  

  .88 
  

  

  .96 
  

  

  1.16 
  

  

  .77 
  

  

  1.00* 
  

  

  .81 
  

  

  .87 
  

  

  1864 
  

  

  .48 
  

  

  .56 
  

  

  .74 
  

  

  .75 
  

  

  .86 
  

  

  .79 
  

  

  .51 
  

  

  .61 
  

  

  .97 
  

  

  .85t 
  

  

  .87 
  

  

  .73 
  

  

  1865 
  

  

  1.00 
  

   1.00 
  

  

  1.36 
  

   1.00* 
  

  

  1.06 
  

   1.00 
  

  

  1.08 
  

   1.08 
  

  

  .80 
  

  

  1.11 
  

  

  .99 
  

  

  1.61 
  

   1.52 
  

  

  .94 
  

   1.15 
  

  

  i."i(>" 
  

  

  .93t 
  

   1.03t 
  

  

  1.33 
  

   1.36 
  

  

  1.02 
  

  

  1866 
  

  

  1.13 
  

  

  

  

  Annual 
  mean 
  in 
  inches. 
  

  

  25.11 
  

  

  25.69 
  

  

  41.96 
  

  

  32.24 
  

  

  42.88 
  

  

  42.18 
  

  

  31.74 
  

  

  28.62 
  

  

  17.34 
  

  

  25.55 
  

  

  30.48 
  

  

  31.25 
  

  

  * 
  Ratio 
  of 
  the 
  nearest 
  stations 
  for 
  the 
  year. 
  Those 
  of 
  1866, 
  Fort 
  Ripley 
  and 
  Fort 
  Ridgley 
  are 
  the 
  

   average 
  within 
  less 
  than 
  . 
  01 
  of 
  those 
  stations 
  in 
  Minnesota 
  west 
  of 
  the 
  Mississippi, 
  

   t 
  Ratios 
  of 
  the 
  Bellevue 
  records. 
  

  

  A 
  careful 
  study 
  of 
  this 
  table 
  brings 
  out 
  several 
  interesting 
  facts, 
  of 
  

   which 
  we 
  may 
  mention 
  the 
  following 
  as 
  most 
  important. 
  The 
  mean 
  

   ratio 
  of 
  1864 
  is 
  the 
  smallest 
  of 
  the 
  series, 
  and 
  as 
  all 
  the 
  ratios 
  for 
  that 
  

   year 
  fall 
  below 
  the 
  average 
  of 
  the 
  several 
  stations, 
  it, 
  so 
  far 
  as 
  dryness 
  

   is 
  concerned, 
  was 
  favorable 
  to 
  the 
  increase 
  and 
  migrations 
  of 
  the 
  locusts; 
  

   and, 
  as 
  heretofore 
  stated, 
  they 
  did 
  appear 
  in 
  portions 
  of 
  the 
  Northwest, 
  

  

  206 
  Tables 
  and 
  Results 
  of 
  the 
  Precipitations 
  of 
  Raiu 
  and 
  Snow 
  in 
  the 
  United 
  States, 
  147-152. 
  

  

  