﻿702 
  

  

  summer 
  ; 
  the 
  young 
  larva 
  eats 
  out 
  a 
  bud 
  and 
  hibernates 
  in 
  it 
  ; 
  in 
  

   the 
  spring 
  it 
  attacks 
  the 
  young 
  swelHng 
  buds 
  ; 
  as 
  the 
  twigs 
  grow, 
  

   the 
  larva 
  often 
  eats 
  only 
  one 
  side 
  of 
  them, 
  and 
  thus 
  causes 
  a 
  pecuhar 
  

   curved 
  growth, 
  the 
  so-called 
  " 
  Posttorner," 
  which 
  seriously 
  depre- 
  

   ciates 
  the 
  value 
  of 
  the 
  trees 
  ; 
  the 
  larvae 
  pupate 
  early 
  in 
  June. 
  There 
  

   is 
  only 
  one 
  generation 
  in 
  Europe, 
  but 
  as 
  allied 
  species 
  in 
  the 
  U.S.A. 
  

   have 
  two 
  generations 
  annually, 
  it 
  is 
  possible 
  that 
  R. 
  buoliana 
  will 
  

   develop 
  two 
  broods 
  in 
  this 
  climate 
  and 
  thus 
  become 
  doubly 
  injurious. 
  

  

  Hyslop 
  (J. 
  A.). 
  Soil 
  Fumigation. 
  — 
  Jl. 
  Econ. 
  Ent., 
  Concord, 
  vii, 
  no. 
  4, 
  

   August 
  1914, 
  pp. 
  305-312, 
  1 
  table. 
  

  

  An 
  account 
  of 
  experiments 
  to 
  determine 
  whether 
  subterranean 
  

   insects 
  can 
  be 
  effectively 
  destroyed 
  by 
  fumigating 
  the 
  soil 
  with 
  sodium 
  

   cyanide 
  is 
  given. 
  There 
  are 
  at 
  present 
  serious 
  disadvantages 
  in 
  the 
  

   use 
  of 
  this 
  poisonous 
  compound 
  because 
  it 
  kills 
  the 
  beneficial 
  nitrifying 
  

   bacteria 
  of 
  the 
  soil 
  as 
  well 
  as 
  the 
  pest. 
  It 
  is 
  believed, 
  however, 
  that 
  

   the 
  soil 
  contains 
  protozoa 
  which 
  feed 
  on 
  these 
  bacteria 
  and 
  these 
  would 
  

   also 
  be 
  killed 
  by 
  the 
  sodium 
  cyanide, 
  with 
  the 
  result 
  that 
  the 
  newly 
  

   introduced 
  bacteria 
  would 
  flourish 
  more 
  than 
  ever, 
  the 
  soil 
  being 
  

   improved. 
  In 
  Hawaii, 
  where 
  protozoa 
  are 
  very 
  abundant 
  in 
  the 
  

   soil, 
  fumigation 
  with 
  carbon 
  bisulphide 
  has 
  acted 
  as 
  a 
  decided 
  stimulus 
  

   to 
  crops. 
  The 
  sodium 
  cyanide 
  as 
  used 
  in 
  following 
  experiments 
  was 
  

   too 
  expensive 
  for 
  farm 
  use, 
  but 
  it 
  is 
  thought 
  that 
  it 
  can 
  be 
  produced 
  

   in 
  a 
  much 
  cheaper 
  form 
  and 
  can 
  be 
  used 
  in 
  smaller 
  quantities. 
  The 
  

   cyanide 
  used 
  was 
  a 
  mixture 
  containing 
  : 
  Sodium 
  cyanide, 
  74 
  to 
  76 
  

   per 
  cent. 
  ; 
  alkaline 
  chlorides, 
  16-24 
  per 
  cent. 
  ; 
  inert 
  substances, 
  

   2-8 
  per 
  cent. 
  Experiments 
  showed 
  that 
  sodium 
  cyanide 
  cannot 
  be 
  

   placed 
  in 
  the 
  soil 
  with 
  the 
  fertiliser 
  at 
  the 
  time 
  of 
  sowing, 
  nor 
  during 
  

   subsequent 
  cultivation, 
  but 
  must 
  be 
  applied 
  at 
  least 
  forty 
  days 
  pre- 
  

   viously, 
  because 
  this 
  substance 
  was 
  found 
  to 
  be 
  decreasingly 
  poisonous 
  

   up 
  to 
  from 
  twenty-six 
  to 
  forty 
  days 
  after 
  application. 
  Field 
  

   experiments 
  corroborated 
  these 
  results 
  in 
  the 
  laboratory. 
  Wire- 
  worms 
  

   attacking 
  potatoes 
  were 
  found 
  to 
  be 
  effectively 
  destroyed 
  by 
  the 
  use 
  of 
  

   sodium 
  cyanide. 
  On 
  the 
  1st 
  October, 
  the 
  cyanide 
  was 
  placed 
  by 
  

   hand 
  in 
  15 
  potato 
  hills, 
  at 
  the 
  rate 
  of 
  300 
  pounds 
  per 
  acre. 
  On 
  4th 
  

   October 
  when 
  three 
  of 
  the 
  treated 
  hills 
  were 
  examined, 
  the 
  larvae 
  

   were 
  found 
  inactive 
  and 
  died 
  three 
  days 
  later. 
  On 
  9th 
  October, 
  when 
  

   the 
  remaining 
  treated 
  hills 
  were 
  dug 
  out, 
  no 
  living 
  insects 
  were 
  to 
  be 
  

   found 
  above 
  the 
  depth 
  to 
  which 
  the 
  cyanide 
  had 
  been 
  introduced, 
  i.e., 
  

   six 
  inches. 
  

  

  Goodwin 
  (W. 
  H.). 
  Some 
  Factors 
  affecting 
  Results 
  in 
  the 
  Use 
  of 
  High 
  

   Temperature 
  for 
  the 
  Control 
  of 
  Insects 
  injuring 
  Cereal 
  Products. 
  — 
  

  

  JL 
  Econ. 
  Entom., 
  Concord, 
  vii, 
  no. 
  4, 
  August 
  1914,, 
  pp. 
  313-322. 
  

  

  In 
  treating 
  flour 
  mills 
  for 
  the 
  destruction 
  of 
  insect 
  pests 
  affecting 
  

   cereals, 
  the 
  practical 
  value 
  of 
  high 
  temperature 
  at 
  48° 
  C. 
  to 
  50° 
  C. 
  is 
  

   much 
  lessened 
  when 
  the 
  heated 
  atmosphere 
  contains 
  moisture 
  in 
  

   proportions 
  greater 
  than 
  40-50 
  per 
  cent. 
  Experiments 
  show 
  that 
  

   50-55° 
  C, 
  kills 
  all 
  stages 
  of 
  cereal 
  insect 
  pests 
  if 
  they 
  are 
  subjected 
  

   to 
  this 
  temperature 
  for 
  1 
  or 
  2 
  hours. 
  Where 
  moisture 
  is 
  present, 
  an 
  

   increase 
  in 
  the 
  amount 
  of 
  radiating 
  surface 
  is 
  essential 
  and 
  failure 
  to 
  

  

  