﻿196 
  EEPOET 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  injury 
  it 
  did 
  to 
  the 
  elms 
  and 
  other 
  shade 
  trees, 
  but 
  because 
  it 
  was 
  con- 
  

   tinually 
  spinning 
  down 
  on 
  persons 
  who 
  happened 
  to 
  be 
  passing 
  under- 
  

   neath 
  the 
  infested 
  trees. 
  

  

  Practical 
  considerations 
  that 
  result 
  from 
  the 
  differences^ 
  

   IN 
  the 
  TWO 
  SPECIES. 
  — 
  The 
  illustration 
  of 
  the 
  differences 
  between 
  the 
  

   two 
  species 
  of 
  Canker 
  Worms 
  may 
  seem 
  unimportant 
  and 
  trivial 
  to 
  the 
  

   horticulturist, 
  however 
  much 
  they 
  may 
  interest 
  the 
  entomologist. 
  Yet 
  

   it 
  is 
  of 
  much 
  practical 
  importance 
  to 
  know 
  liow 
  to 
  make 
  the 
  distinc- 
  

   tion. 
  From 
  present 
  knowledge 
  of 
  the 
  subject, 
  it 
  is 
  highly 
  probable- 
  

   that, 
  just 
  as 
  the 
  moths 
  of 
  the 
  one 
  species 
  appear 
  mostly 
  in 
  early 
  springy 
  

   and 
  of 
  the 
  other 
  mostly 
  late 
  in 
  the 
  fall, 
  so 
  each 
  is, 
  in 
  a 
  general 
  sense^ 
  

   confined 
  to 
  particular 
  plants 
  (though 
  not 
  exclusively 
  so), 
  the 
  Spring 
  

   species 
  preferring 
  our 
  fruit 
  trees, 
  and 
  the 
  Fall 
  species 
  preferring 
  the 
  

   elm. 
  Thus 
  the 
  time 
  to 
  put 
  forth 
  our 
  efforts 
  to 
  catch 
  and 
  destroy 
  the 
  

   wingless 
  moths 
  will 
  vary 
  according 
  to 
  the 
  nature 
  of 
  the 
  tree 
  to 
  be 
  pro- 
  

   tected 
  and 
  the 
  insect 
  to 
  be 
  dealt 
  with. 
  

  

  "In 
  the 
  case 
  of 
  the 
  Spring 
  species, 
  the 
  eggs 
  being 
  secreted, 
  for 
  the 
  

   most 
  part, 
  under 
  loose 
  bark, 
  the 
  scraping 
  of 
  the 
  tree 
  and 
  otherwise 
  

   cleansing 
  it 
  of 
  dead 
  leaves, 
  cocoons, 
  larva-cases, 
  &c., 
  a 
  short 
  time 
  before 
  

   the 
  hatching 
  of 
  the 
  worms, 
  or 
  before 
  the 
  buds 
  of 
  the 
  tree 
  commence 
  ta 
  

   open, 
  will 
  prove 
  an 
  effectual 
  preventive 
  measure 
  j 
  as 
  thereby 
  many 
  of 
  

   the 
  eggs 
  will 
  be 
  destroyed. 
  Moreover, 
  a 
  tree 
  kept 
  clean 
  of 
  loose 
  bark 
  

   will 
  be 
  less 
  subject 
  to 
  its 
  attacks. 
  The 
  same 
  argument 
  will 
  not 
  apply 
  

   to 
  the 
  Fall 
  species, 
  which 
  attaches 
  its 
  eggs 
  in 
  any 
  exposed 
  position. 
  It 
  

   would 
  seem, 
  also, 
  that 
  the 
  mode 
  of 
  trapping 
  the 
  moths 
  will 
  have 
  to 
  be 
  

   somewhat 
  modified, 
  according 
  to 
  the 
  species 
  to 
  be 
  dealt 
  with 
  ; 
  for 
  while 
  

   Dr. 
  LeBaron 
  found 
  the 
  tin 
  and 
  rope 
  trap 
  described 
  above 
  so 
  effectual 
  

   with 
  the 
  Spring 
  Canker 
  Worm, 
  it 
  does 
  not 
  appear 
  to 
  afford 
  a 
  coinplete 
  

   barrier 
  to 
  the 
  Fall 
  species, 
  judging 
  from 
  the 
  following 
  notes, 
  kindly 
  fur- 
  

   nished 
  by 
  Mr. 
  Mann. 
  It 
  will 
  be 
  noticed 
  that 
  Mr. 
  Mann 
  used 
  zinc 
  instead 
  

   of 
  tin, 
  from 
  its 
  less 
  liability 
  to 
  rust. 
  

  

  Nov. 
  8, 
  1873. 
  Warm 
  last 
  night, 
  with 
  rain, 
  \vhich 
  still 
  continues. 
  Found 
  25 
  9 
  and 
  

   one 
  ^pometaria. 
  Found 
  4 
  of 
  the 
  $ 
  above 
  the 
  LeBaron 
  zinc 
  band. 
  

  

  Nov. 
  9. 
  Found 
  2^, 
  37 
  ^ 
  pometaria 
  ; 
  2$ 
  above 
  the 
  zinc 
  band. 
  

  

  Nov. 
  12. 
  Snow 
  last 
  night, 
  followed 
  by 
  cold 
  sleet. 
  Found 
  ^^pomeiaria, 
  1 
  above^ 
  

   the 
  zinc. 
  

  

  Nov. 
  15. 
  Only 
  6 
  <$ 
  pometaria 
  ; 
  none 
  above 
  the 
  band. 
  Last 
  three 
  days 
  freezing 
  cold^ 
  

   hut 
  not 
  stormy. 
  

  

  Nov. 
  18. 
  Several 
  days 
  of 
  rain 
  and 
  snow. 
  1 
  <$ 
  pomctaiia. 
  

  

  Nov. 
  22. 
  6 
  2,2 
  $pometana. 
  

  

  Dec. 
  4. 
  Yesterday 
  thawing; 
  to-day 
  also. 
  The 
  weather 
  since 
  Nov. 
  22 
  has 
  been 
  cold,, 
  

   with 
  occasional 
  snow, 
  and 
  the 
  ground 
  has 
  been 
  frozen, 
  and 
  I 
  have 
  failed 
  to 
  lind 
  any 
  

   Anisoptei'ijx 
  pomeiaria 
  ; 
  but 
  to-day 
  I 
  caught 
  11 
  ^ 
  , 
  102 
  $ 
  , 
  2 
  9 
  above 
  the 
  zinc 
  band. 
  I 
  have 
  

   no 
  doubt 
  that 
  the 
  smallness 
  of 
  the 
  number 
  ol 
  9 
  found 
  above 
  the 
  bands 
  of 
  zinc 
  is 
  due 
  

   to 
  my 
  promptness 
  and 
  diligence 
  in 
  detecting 
  aud 
  destroying 
  them 
  before 
  they 
  have 
  

   had 
  time 
  to 
  mount 
  the 
  tree 
  ; 
  because, 
  according 
  to 
  the 
  theory 
  on 
  which 
  the 
  experiment 
  

   was 
  tried, 
  the 
  9 
  ought 
  to 
  be 
  found 
  on 
  the 
  outside 
  of 
  the 
  strips, 
  if 
  their 
  ascent 
  has 
  been 
  

   prevented 
  by 
  them; 
  while 
  in 
  fact 
  (excluding 
  those 
  found 
  on 
  the 
  house 
  or 
  fence, 
  &c.)y 
  

   the 
  majority 
  of 
  the 
  9 
  have 
  been 
  caught 
  before 
  they 
  reached 
  the 
  bands; 
  further, 
  be- 
  

  

  