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  of 
  the 
  cocoons 
  were 
  affected. 
  Some 
  40-50 
  per 
  cent, 
  of 
  the 
  cocoons 
  

   were 
  also 
  infested 
  by 
  parasites, 
  the 
  description 
  of 
  which 
  is 
  held 
  over. 
  

   The 
  author 
  mentions 
  that 
  in 
  August 
  1913 
  he 
  found 
  empty 
  fresh 
  

   cocoons 
  with 
  holes 
  gnawed 
  in 
  them, 
  which 
  are 
  attributed 
  to 
  some 
  

   predaceous 
  insect. 
  The 
  larvae 
  in 
  the 
  cocoons 
  pupate 
  in 
  spring, 
  and 
  

   the 
  sawfly 
  emerges 
  about 
  a 
  fortnight 
  later, 
  usually 
  during 
  May. 
  

   Oviposition 
  starts 
  a 
  fortnight 
  after 
  the 
  issue 
  of 
  the 
  imago. 
  The 
  eggs 
  

   are 
  deposited 
  in 
  two 
  lines 
  on 
  the 
  topmost 
  buds 
  of 
  young 
  shoots 
  of 
  larch, 
  

   also 
  under 
  the 
  tender 
  bark 
  of 
  the 
  upper 
  part 
  of 
  the 
  shoots 
  ; 
  the 
  

   author's 
  observations 
  do 
  not 
  confirm 
  the 
  view 
  that 
  the 
  higher 
  branches 
  

   are 
  preferred 
  by 
  the 
  females 
  for 
  oviposition, 
  but 
  it 
  appears 
  that 
  on 
  the 
  

   sides 
  of 
  the 
  trees 
  exposed 
  to 
  the 
  sun 
  and 
  sheltered 
  from 
  the 
  wind, 
  the 
  

   percentage 
  of 
  infested 
  branches 
  is 
  greater. 
  The 
  eggs 
  are 
  found 
  also, 
  

   although 
  more 
  seldom, 
  in 
  the 
  cavities 
  of 
  the 
  bark, 
  where 
  they 
  are 
  

   laid 
  in 
  fines 
  parallel 
  to 
  the 
  direction 
  of 
  the 
  cracks. 
  The 
  eggs 
  hatch 
  

   about 
  the 
  end 
  of 
  the 
  first 
  week 
  in 
  May, 
  and 
  the 
  young 
  larvae 
  attack 
  

   the 
  more 
  tender 
  needles. 
  Later 
  they 
  congregate 
  and 
  form 
  large 
  nests 
  

   containing 
  as 
  many 
  as 
  40 
  individuals, 
  but 
  after 
  the 
  fourth 
  moult 
  (there 
  

   being 
  five 
  in 
  all) 
  the 
  larvae 
  feed 
  separately. 
  The 
  young 
  larvae 
  chng 
  

   closely 
  to 
  the 
  needles 
  and 
  cannot 
  be 
  dislodged 
  even 
  by 
  violent 
  shaking, 
  

   but 
  the 
  older 
  larvae 
  let 
  themselves 
  fall 
  readily. 
  The 
  greatest 
  damage 
  

   to 
  the 
  trees 
  is 
  done 
  in 
  the 
  first 
  half 
  of 
  July, 
  when 
  the 
  percentage 
  of 
  

   full-grown 
  larvae 
  is 
  greatest. 
  The 
  measures 
  employed 
  against 
  

   N. 
  erichsonii 
  are 
  : 
  — 
  (1) 
  sticky 
  bands 
  on 
  the 
  tree-trunks 
  in 
  order 
  to 
  

   prevent 
  the 
  return 
  to 
  the 
  trees 
  of 
  the 
  larvae 
  which 
  have 
  fallen 
  down 
  ; 
  

   this 
  remedy 
  gave 
  excellent 
  results 
  and 
  its 
  average 
  cost, 
  including 
  the 
  

   renewal 
  of 
  the 
  bands, 
  is 
  about 
  Id. 
  per 
  tree 
  ; 
  (2) 
  the 
  destruction 
  of 
  the 
  

   cocoons 
  by 
  the 
  removal 
  and 
  burning 
  of 
  the 
  vegetable 
  debris 
  on 
  the 
  

   ground 
  ; 
  and 
  (3) 
  disinfecting 
  this 
  debris 
  with 
  carbon 
  bisulphide, 
  either 
  

   by 
  means 
  of 
  an 
  injector, 
  or 
  by 
  placing 
  in 
  the 
  fitter 
  small 
  baUs 
  of 
  cotton 
  

   waste 
  moistened 
  with 
  this 
  chemical. 
  

  

  Aihalia 
  spinarum 
  has 
  done 
  considerable 
  damage 
  to 
  turnips 
  in 
  some 
  

   locafities 
  round 
  Moscow, 
  The 
  first 
  generation 
  is 
  on 
  the 
  wing 
  in 
  the 
  

   beginning 
  of 
  June, 
  but 
  the 
  larvae 
  of 
  the 
  second 
  generation 
  are 
  more 
  

   injurious, 
  appearing 
  in 
  August, 
  when 
  the 
  turnips 
  are 
  in 
  full 
  foliage. 
  

   The 
  larvae 
  eat 
  the 
  leaves, 
  an 
  average 
  of 
  42 
  larvae 
  on 
  a 
  single 
  leaf 
  being 
  

   found 
  near 
  one 
  village 
  ; 
  they 
  feed 
  principally 
  in 
  the 
  morning. 
  The 
  

   larval 
  stage 
  lasts 
  18 
  to 
  20 
  days, 
  the 
  pupal 
  stage 
  about 
  a 
  fortnight. 
  

   The 
  following 
  remedies 
  were 
  experimented 
  upon: 
  — 
  (1) 
  liming 
  of 
  the 
  

   plants 
  before 
  the 
  dew 
  was 
  off, 
  which 
  was 
  done 
  by 
  sifting 
  well-slacked 
  

   Ume 
  over 
  the 
  leaves 
  ; 
  the 
  results 
  were 
  satisfactory, 
  as 
  the 
  larvae 
  left 
  

   these 
  plants, 
  which 
  were 
  able 
  to 
  recover 
  and 
  gave 
  good 
  crops 
  ; 
  (2) 
  

   spraying 
  with 
  Paris 
  green 
  (| 
  lb, 
  of 
  green, 
  1 
  lb, 
  of 
  freshly 
  slacked 
  lime, 
  

   3 
  gafions 
  of 
  water) 
  which 
  gave 
  the 
  best 
  results, 
  the 
  larva 
  perishing 
  in 
  

   great 
  numbers 
  ; 
  (3) 
  spraying 
  with 
  barium 
  chloride 
  (1 
  lb. 
  of 
  barium 
  

   chloride 
  in 
  4J 
  gallons 
  of 
  water) 
  gave 
  less 
  satisfactory 
  results 
  and 
  burnt 
  

   the 
  leaves 
  ; 
  (4) 
  the 
  larvae 
  are 
  greedily 
  devoured 
  by 
  ducks 
  and 
  

   chickens, 
  and 
  poultry 
  can 
  usefully 
  be 
  let 
  out 
  on 
  attacked 
  fields 
  ; 
  (5) 
  

   the 
  larvae 
  may 
  also 
  be 
  collected 
  by 
  means 
  of 
  an 
  entomologist's 
  net. 
  

  

  Hylemyia 
  antiqua 
  is 
  widespread 
  in 
  the 
  government 
  and 
  injures 
  

   onions 
  by 
  attacking 
  their 
  bulbs, 
  sometimes 
  even 
  boring 
  into 
  the 
  leaves. 
  

   Occasionally 
  as 
  many 
  as 
  20 
  larvae 
  were 
  found 
  on 
  one 
  plant, 
  the 
  usual 
  

   number 
  being 
  3-12. 
  The 
  first 
  damage 
  was 
  noticed 
  on 
  17th 
  June, 
  

  

  