﻿THE 
  ARMY 
  WORM: 
  NUMBER 
  OF 
  ANNUAL 
  BROODS. 
  119 
  

  

  among 
  entomologists 
  that 
  there 
  was 
  but 
  one 
  annual 
  brood 
  of 
  the 
  species, 
  

   especially 
  in 
  the 
  Northern 
  States, 
  no 
  absolute 
  evidence 
  of 
  a 
  second 
  brood 
  

   having 
  been 
  obtained." 
  

  

  It 
  is 
  true 
  that 
  Professor 
  Thomas, 
  in 
  the 
  Prairie 
  Farmer 
  of 
  June 
  20, 
  

   1861, 
  expressed 
  his 
  belief 
  in 
  two 
  broods, 
  and 
  in 
  the 
  same 
  periodical, 
  

   August 
  22, 
  1861, 
  made 
  the 
  following 
  statement 
  : 
  

  

  A 
  few 
  years 
  back 
  when 
  tlie 
  Army 
  Worm 
  appeared 
  in 
  this 
  county, 
  after 
  disappear- 
  

   ing, 
  they 
  were 
  again 
  seen 
  on 
  some 
  farms, 
  late 
  in 
  the 
  fall, 
  in 
  considerable 
  numbers. 
  

   In 
  one 
  place 
  they 
  were 
  in 
  such 
  numbers 
  that 
  they 
  cut 
  all 
  the 
  grass 
  in 
  a 
  corn-field 
  and 
  

   even 
  attacked 
  the 
  hard 
  leaves 
  of 
  the 
  ripening 
  corn. 
  

  

  This 
  is 
  evidently 
  from 
  hearsay, 
  and 
  cannot 
  be 
  considered 
  a 
  well- 
  

   authenticated 
  instance, 
  because 
  such 
  accounts 
  in 
  the 
  fall 
  generally 
  re- 
  

   fer 
  to 
  Laphygma 
  friigiperda; 
  yet 
  in 
  1880 
  Thomas 
  says 
  (10th 
  111. 
  Ent. 
  

   Eep., 
  p. 
  27) 
  : 
  

  

  In 
  fact 
  I 
  brought 
  forward 
  absolute 
  evidence 
  of 
  the 
  correctness 
  of 
  this 
  opinion 
  by 
  show- 
  

   ing 
  at 
  least 
  one 
  well-attested 
  case 
  of 
  both 
  the 
  spring 
  and 
  fall 
  broods 
  of 
  the 
  worms 
  ap- 
  

   pearing 
  in 
  this 
  county 
  the 
  same 
  year 
  in 
  large 
  and 
  injurious 
  numbers. 
  

  

  Kirkpatrick 
  had 
  also 
  expressed 
  his 
  belief 
  that 
  there 
  were 
  two 
  broods, 
  

   but 
  with 
  these 
  exceptions 
  entomologists 
  considered 
  the 
  insect 
  one- 
  

   brooded; 
  indeed, 
  Thomas, 
  later, 
  gave 
  up 
  his 
  belief, 
  as 
  he 
  says, 
  and 
  sided 
  

   on 
  this 
  point 
  with 
  Walsh 
  {Prairie 
  Farmer 
  ^ 
  October 
  31, 
  1861, 
  p. 
  293). 
  In 
  

   1880 
  we 
  wrote: 
  

  

  Our 
  experiments 
  in 
  1876 
  proved 
  conclusively 
  that 
  there 
  were 
  always 
  two 
  and 
  some- 
  

   times 
  three 
  generations 
  in 
  the 
  latitude 
  of 
  Saint 
  Louis. 
  The 
  facts 
  that 
  we 
  also 
  re- 
  

   corded 
  as 
  to 
  the 
  remarkably 
  rapid 
  development 
  of 
  the 
  worm, 
  i. 
  e. 
  that 
  it 
  can 
  reach 
  

   full 
  growth 
  within 
  a 
  fortnight 
  after 
  hatching, 
  lent 
  favor 
  to 
  the 
  idea, 
  in 
  our 
  mind, 
  

   that 
  there 
  might 
  be 
  even 
  more 
  generations. 
  Subsequent 
  experience, 
  and 
  especially 
  

   that 
  of 
  the 
  present 
  year, 
  has 
  convinced 
  us 
  that 
  there 
  is 
  usually 
  one 
  other 
  generation 
  

   there, 
  and 
  it 
  is 
  but 
  natural 
  to 
  suppose 
  that 
  there 
  are 
  still 
  more 
  in 
  more 
  southern 
  lati- 
  

   tudes. 
  The 
  moths 
  are 
  to 
  be 
  found 
  laying 
  their 
  eggs 
  as 
  soon 
  as 
  vegetation 
  starts 
  in 
  

   the 
  spring, 
  and 
  there 
  is 
  a 
  succession 
  of 
  broods 
  from 
  that 
  time 
  till 
  winter 
  sets 
  in 
  ; 
  the 
  

   number 
  differing 
  according 
  to 
  latitude 
  and 
  the 
  length 
  of 
  the 
  growing 
  season. 
  Thus, 
  

   Professor 
  Comstock 
  reports 
  it 
  as 
  having 
  been 
  received 
  at 
  the 
  Department 
  of 
  Agricult- 
  

   ure, 
  in 
  the 
  larva 
  state, 
  during 
  every 
  month 
  of 
  the 
  winter 
  of 
  1879-^'80 
  from 
  the 
  South- 
  

   ern 
  States, 
  where, 
  during 
  the 
  mild 
  weather, 
  it 
  was 
  active 
  and 
  injurious 
  to 
  oats 
  and 
  

   other 
  grain. 
  (American 
  Entomologist, 
  v. 
  3, 
  pp. 
  184, 
  185.) 
  

  

  The 
  winter 
  of 
  1880-'81 
  was 
  so 
  severe 
  all 
  over 
  the 
  country 
  that 
  the 
  

   worms 
  were 
  not 
  noticed 
  j 
  but 
  in 
  the 
  winter 
  of 
  1881-'82 
  they 
  again 
  made 
  

   their 
  appearance. 
  

  

  Sod 
  was 
  taken 
  from 
  the 
  Department 
  grounds 
  at 
  Washington 
  and 
  

   placed 
  in 
  breeding 
  cages 
  as 
  food 
  for 
  other 
  larvae 
  shortly 
  before 
  Christmas. 
  

   January 
  3 
  a 
  number 
  of 
  young 
  Army 
  Worms, 
  which 
  had 
  evidently 
  been 
  

   hibernating 
  at 
  the 
  roots, 
  were 
  found 
  feeding 
  upon 
  the 
  grass 
  leaves. 
  Jan- 
  

   uary 
  12 
  an 
  active 
  larva 
  one-third 
  grown 
  was 
  taken, 
  out 
  of 
  doors. 
  Jan- 
  

   uary 
  15 
  another 
  larva 
  which 
  had 
  passed 
  through 
  its 
  second 
  molt 
  was 
  

   found 
  under 
  similar 
  circumstances. 
  The 
  first 
  moth 
  from 
  these 
  larvse 
  

   made 
  its 
  appearance 
  March 
  3. 
  January 
  23 
  the 
  worms 
  were 
  received 
  

   from 
  Ashland, 
  Clay 
  County, 
  Alabama, 
  with 
  the 
  report 
  that 
  they 
  were 
  

  

  