﻿620 
  REPOET 
  UNITED 
  STATES 
  GEOLOGICAL 
  SURVEY. 
  

  

  progeny 
  of 
  these 
  spread 
  northward 
  in 
  1874, 
  but 
  while 
  fresh 
  swarms 
  

   entered 
  the 
  State 
  in 
  1874 
  from 
  the 
  northwest, 
  they 
  did 
  not, 
  probably, 
  

   add 
  much 
  to 
  the 
  stock 
  of 
  eggs 
  deposited 
  by 
  the 
  Minnesota 
  brood, 
  and 
  

   Mr. 
  Whitman 
  thinks 
  it 
  " 
  probable 
  that 
  the 
  locusts 
  which 
  hatched 
  in 
  

   Minnesota 
  last 
  spring 
  were, 
  to 
  a 
  considerable 
  extent, 
  the 
  descendants 
  

   of 
  the 
  swarms 
  which 
  entered 
  the 
  State 
  in 
  1873." 
  

  

  Mr. 
  Whitman 
  believes 
  that 
  in 
  Minnesota 
  there 
  is 
  not 
  a 
  return-flight 
  

   of 
  freshly-fledged 
  locusts 
  toward 
  the 
  Eocky 
  Mountains, 
  as 
  shown 
  by 
  Mr. 
  

   Riley 
  and 
  others 
  to 
  take 
  place 
  in 
  Nebraska, 
  Kansas, 
  and 
  Missouri. 
  On 
  

   the 
  contrary, 
  " 
  the 
  wind 
  which 
  sweep 
  clear 
  away 
  the 
  hatching-swarms 
  

   of 
  the 
  more 
  southern 
  States 
  carry 
  our 
  own 
  but 
  a 
  few 
  miles 
  from 
  their 
  

   birthplace." 
  He 
  seems 
  to 
  incline 
  to 
  the 
  belief 
  that 
  " 
  some 
  cause 
  for 
  

   the 
  fact 
  that 
  portions 
  of 
  our 
  swarms 
  remain 
  here 
  to 
  breed 
  can 
  be 
  found 
  

   in 
  an 
  early 
  stage 
  of 
  egg-laying. 
  While 
  those 
  observed 
  late 
  in 
  summer 
  

   to 
  fly 
  northwestward 
  did 
  not 
  lay 
  eggs, 
  " 
  on 
  the 
  other 
  hand 
  our 
  own 
  

   (Minnesota) 
  stock 
  were 
  seen 
  in 
  1875 
  to 
  be 
  laying 
  within 
  eight 
  days 
  

   after 
  their 
  liight 
  commenced, 
  and 
  in 
  the 
  places 
  where 
  they 
  first 
  alighted, 
  

   and 
  during 
  the 
  past 
  season 
  the 
  laying 
  had 
  already 
  begun 
  on 
  the 
  3d 
  of 
  

   July, 
  and 
  by 
  the 
  10th 
  had 
  become 
  general 
  in 
  the 
  western 
  part 
  of 
  Kicollet 
  

   County, 
  within 
  a 
  few 
  miles 
  from 
  their 
  hatching-ground, 
  and 
  within 
  two 
  

   weeks 
  from 
  the 
  time 
  when 
  the 
  flying 
  began. 
  This 
  early 
  period 
  of 
  laying 
  

   may 
  be 
  of 
  itself 
  a 
  sufficient 
  cause 
  for 
  portions 
  of 
  our 
  swarms 
  remaining 
  

   here, 
  while 
  the 
  less 
  mature 
  pass 
  on." 
  

  

  From 
  one 
  year 
  to 
  another 
  Mr. 
  Whitman 
  has 
  noticed 
  a 
  natural 
  de- 
  

   crease 
  in 
  the 
  number 
  of 
  locusts 
  breeding 
  in 
  Minnesota 
  : 
  

  

  Numbers 
  of 
  locusts 
  have 
  hatched 
  out 
  and 
  have 
  died 
  without 
  reproducing 
  them- 
  

   selves. 
  In 
  this 
  connection, 
  the 
  State 
  of 
  Minnesota 
  has 
  an 
  advantage 
  over 
  more 
  

   southerly 
  regions, 
  in 
  the 
  fact 
  that 
  we 
  are 
  situated 
  nearer 
  to 
  the 
  breeding-grounds 
  of 
  

   invading 
  swarms. 
  Of 
  these, 
  the 
  earlier 
  comers 
  are 
  more 
  likely 
  to 
  pass 
  over 
  us 
  before 
  

   reaching 
  the 
  full 
  period 
  of 
  their 
  development, 
  while 
  the 
  later 
  comers 
  are 
  cut 
  off 
  by 
  

   our 
  earlier 
  frosts; 
  and 
  of 
  the 
  eggs 
  which 
  are 
  left 
  with 
  us, 
  being 
  deposited 
  earlier 
  in 
  

   the 
  season, 
  more 
  are 
  likely 
  to 
  hatch 
  in 
  the 
  fall 
  and 
  become 
  harmless. 
  On 
  the 
  other 
  

   hand, 
  the 
  invaders 
  are 
  more 
  likely 
  to 
  mass 
  their 
  forces 
  in 
  more 
  southerly 
  States, 
  reach 
  

   them 
  in 
  full 
  maturity, 
  and 
  remain 
  later 
  in 
  the 
  season, 
  while 
  the 
  eggs, 
  being 
  dej)Osited 
  

   later 
  than 
  ours, 
  remain 
  mostly 
  unhatohed 
  until 
  spring. 
  These 
  considerations 
  enable 
  

   us 
  to 
  understand 
  why 
  certain 
  counties 
  in 
  Missouri, 
  where 
  the 
  locust 
  hatched 
  in 
  1875. 
  

   presented 
  in 
  May 
  such 
  a 
  picture 
  of 
  devastation 
  and 
  desolation 
  as 
  Minnesota 
  has 
  never 
  

   seen 
  in 
  all 
  its 
  locust 
  experience. 
  

  

  The 
  locust 
  has 
  also 
  become 
  shorter 
  lived, 
  and 
  many 
  were 
  killed 
  by 
  

   the 
  Tachina 
  maggot, 
  while 
  of 
  the 
  invading 
  swarms 
  of 
  the 
  present 
  year 
  

   "large 
  numbers 
  of 
  the 
  bodies 
  of 
  the 
  dead 
  could 
  be 
  found 
  in 
  the 
  fields 
  

   early 
  in 
  September," 
  and 
  " 
  large 
  numbers 
  remained 
  alive 
  until 
  they 
  

   were 
  killed 
  by 
  frost, 
  and 
  even 
  then 
  died 
  with 
  eggs 
  unlaid." 
  Another 
  

   effect 
  of 
  naturalization 
  during 
  the 
  last 
  four 
  years, 
  says 
  Mr. 
  Whitman, 
  is 
  

   that 
  "while 
  it 
  has 
  lost 
  some 
  portion 
  of 
  its 
  inclination 
  or 
  its 
  ability 
  to 
  

   migrate, 
  it 
  has 
  also 
  lost 
  somewhat 
  of 
  its 
  gregarious 
  character." 
  Indeed, 
  

   had 
  it 
  not 
  been 
  for 
  the 
  new-comers 
  in 
  1876, 
  " 
  next 
  year 
  would 
  have 
  seen 
  

   the 
  insects 
  so 
  few 
  and 
  so 
  scattered 
  as 
  to 
  be 
  incapable 
  of 
  great 
  damage, 
  

   and 
  they 
  might 
  become 
  in 
  a 
  year 
  or 
  two 
  as 
  flitting 
  and 
  as 
  unnoticeable 
  

   as 
  the 
  red-legged 
  locust 
  that 
  breeds 
  with 
  us 
  every 
  year." 
  Mr. 
  Whitman 
  

   adds 
  that, 
  " 
  in 
  regard 
  to 
  changes 
  in 
  color 
  and 
  appearance, 
  while 
  the 
  

   locusts 
  which 
  hatched 
  in 
  Minnesota 
  last 
  spring 
  had 
  when 
  fully 
  devel- 
  

   oped 
  something 
  of 
  the 
  darkness 
  and 
  dullness 
  of 
  old 
  age, 
  the 
  brightness 
  

   and 
  fierceness 
  of 
  the 
  fresh 
  invaders 
  was 
  apparent 
  to 
  every 
  one." 
  Mr. 
  

   Whitman 
  concludes, 
  and 
  we 
  think 
  the 
  facts 
  reported 
  by 
  him 
  bear 
  out 
  

   his 
  statement: 
  " 
  Nothing 
  is 
  more 
  certain 
  than 
  that 
  we 
  might, 
  by 
  gen- 
  

   eral 
  and 
  continued 
  effort, 
  practically 
  eradicate 
  the 
  offspring 
  of 
  almost 
  

   any 
  one 
  year's 
  invasion; 
  nothing 
  is 
  more 
  probable 
  than 
  tbat 
  in 
  almost 
  

  

  