﻿REMEDIES 
  AGAINST 
  CANKER 
  WORMS. 
  183 
  

  

  species 
  were 
  not 
  devoloped 
  unless 
  in 
  a 
  very 
  early 
  stage 
  of 
  the 
  embryo.'' 
  

   Specimens 
  of 
  the 
  larvae 
  were 
  gathered 
  by 
  him 
  June 
  15. 
  

  

  Mr. 
  Mann 
  found 
  the 
  larvae 
  descending 
  from 
  elm 
  and 
  apple 
  trees 
  on 
  

   the 
  17th 
  of 
  June, 
  1872. 
  

  

  It 
  is 
  a 
  singular 
  fact 
  that 
  the 
  larva 
  undergoes 
  but 
  two 
  molts 
  exclu. 
  

   sive 
  of 
  that 
  which 
  takes 
  place 
  underground 
  in 
  the 
  transformation 
  to 
  

   the 
  chrysalis. 
  

  

  Season 
  of 
  pupation. 
  — 
  The 
  chrysalis 
  is 
  not 
  formed 
  till 
  about 
  a 
  month 
  

   after 
  the 
  larva 
  has 
  entered 
  the 
  ground. 
  

  

  Food-plants. 
  — 
  This 
  species 
  is 
  found 
  more 
  particularly 
  on 
  the 
  elm, 
  

   and 
  occurs 
  also 
  on 
  the 
  apple, 
  but 
  in 
  our 
  experiments 
  upon 
  larvae 
  kept 
  

   in 
  confinement, 
  in 
  1875, 
  we 
  did 
  not 
  perceive 
  that 
  the 
  larvae 
  had 
  any 
  pref- 
  

   erence 
  for 
  one 
  over 
  the 
  other 
  of 
  the 
  leaves 
  of 
  elm, 
  apple, 
  and 
  cherry, 
  

   though 
  they 
  evidently 
  relished 
  peach 
  leaves 
  the 
  least, 
  and 
  rejected 
  them 
  

   when 
  the 
  other 
  three 
  kinds 
  could 
  be 
  had. 
  

  

  One 
  or 
  the 
  other 
  species 
  — 
  it 
  is 
  uncertain 
  which 
  — 
  attacks 
  the 
  maple. 
  

  

  REMEDIES 
  AND 
  PREVENTIVE 
  MEASURES 
  APPLICABLE 
  TO 
  BOTH 
  

  

  SPECIES. 
  

  

  It 
  may 
  be 
  laid 
  down 
  as 
  a 
  maxim 
  that 
  no 
  injurious 
  insect 
  can 
  be 
  com- 
  

   batted 
  successfully 
  without 
  a 
  thorough 
  knowledge 
  of 
  its 
  habits 
  and 
  

   transformations. 
  This 
  knowledge 
  having 
  been 
  conveyed 
  in 
  the 
  preced- 
  

   ing 
  pages, 
  we 
  will 
  now 
  consider 
  what 
  are 
  the 
  proper 
  remedies 
  for 
  the 
  

   ravages 
  of 
  these 
  insects. 
  The 
  absence 
  of 
  wings 
  in 
  the 
  female 
  gives 
  us 
  

   at 
  once 
  a 
  i)ower 
  over 
  her 
  which 
  is 
  half 
  the 
  victory 
  ; 
  and 
  anything 
  that 
  

   will 
  prevent 
  her 
  ascending 
  the 
  trunk 
  will, 
  in 
  a 
  great 
  measure 
  (but, 
  as 
  

   we 
  shall 
  see 
  presently, 
  not 
  entirely), 
  x)reserve 
  the 
  tree 
  from 
  the 
  ravages 
  

   of 
  the 
  worm. 
  

  

  In 
  the 
  following 
  account 
  the 
  author's 
  previous 
  writings 
  have 
  been 
  

   largely 
  drawn 
  upon, 
  and 
  parts 
  in 
  quotation 
  marks 
  not 
  accredited 
  are 
  

   taken 
  therefrom. 
  The 
  remedies 
  are 
  appropriate 
  for 
  either 
  species 
  here 
  

   considered, 
  though 
  they 
  should 
  be 
  applied 
  most 
  assiduously 
  either 
  in 
  

   spring 
  or 
  autumn, 
  according 
  to 
  the 
  species 
  to 
  be 
  dealt 
  with. 
  

  

  STICKY 
  SUBSTANCES. 
  

  

  IsTumerous 
  indeed 
  have 
  been 
  the 
  devices 
  — 
  patented 
  or 
  unj)atented 
  — 
  

   which 
  have 
  at 
  different 
  times 
  and 
  in 
  different 
  parts 
  of 
  the 
  country 
  been 
  

   used 
  to 
  accomplish 
  the 
  desired 
  end 
  5 
  and 
  every 
  year 
  our 
  agricultural 
  

   journals 
  report 
  individual 
  experiments 
  with 
  some 
  one 
  or 
  other 
  of 
  these 
  

   devices 
  — 
  some 
  favorable 
  and 
  others 
  adverse. 
  Those 
  most 
  generally 
  in 
  

   use 
  have 
  consisted 
  of 
  some 
  application 
  of 
  a 
  sticky 
  nature 
  to 
  the 
  trunk 
  of 
  

   the 
  tree, 
  whereby 
  the 
  feet 
  of 
  the 
  moth 
  maybe 
  encumbered 
  and 
  from 
  which 
  

   she 
  may 
  be 
  unable 
  to 
  escape. 
  Various 
  substances 
  have 
  been 
  used 
  for 
  

   this 
  purpose, 
  of 
  which 
  I 
  will 
  mention 
  tar, 
  bird-lime, 
  refuse 
  sorghum 
  mo- 
  

   lasses, 
  printers' 
  ink, 
  slow-drying 
  varnishes, 
  and 
  melted 
  india-rubber; 
  this 
  

   last 
  always 
  retaining 
  its 
  soft 
  viscid 
  state, 
  while 
  the 
  rest 
  become 
  dry 
  and 
  

   hardened 
  by 
  exposure 
  to 
  the 
  air. 
  

  

  