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  water. 
  After 
  the 
  first 
  spraying 
  40 
  per 
  cent, 
  of 
  the 
  insects 
  perished 
  ; 
  

   the 
  second 
  spraying 
  raised 
  this 
  figure 
  to 
  80 
  per 
  cent. 
  ; 
  the 
  young 
  plants, 
  

   which 
  at 
  the 
  time 
  of 
  spraying 
  (25th-26th 
  June) 
  had 
  two 
  or 
  four 
  true 
  

   leaves, 
  did 
  not 
  suffer 
  from 
  the 
  insecticide. 
  

  

  Euxoa 
  (Agrotis) 
  segetum, 
  Schiff., 
  appeared 
  at 
  the 
  same 
  time 
  on 
  the 
  

   cotton 
  fields 
  of 
  the 
  Station 
  of 
  Adijan. 
  During 
  the 
  daytime 
  the 
  young 
  

   larvae 
  eat 
  the 
  parts 
  of 
  the 
  plants 
  below 
  the 
  surface 
  of 
  the 
  soil, 
  the 
  larger 
  

   individuals 
  dragging 
  other 
  plants 
  into 
  their 
  holes 
  ; 
  at 
  night 
  they 
  

   gnaw 
  the 
  cotyledons 
  of 
  the 
  seedlings. 
  These 
  larvae 
  also 
  feed 
  on 
  

   certain 
  weeds 
  common 
  on 
  cotton 
  plantations 
  in 
  Fergana, 
  such 
  as 
  

   Convolvulus, 
  Malva 
  rotundifolia 
  and 
  Plantago 
  ; 
  they 
  also 
  attack 
  maize. 
  

   These 
  larvae 
  did 
  considerable 
  damage 
  at 
  Pachtalykulsk, 
  to 
  a 
  new 
  

   variety 
  of 
  cotton 
  brought 
  by 
  A. 
  N. 
  Liubtchenko 
  from 
  America 
  and 
  

   sown 
  for 
  experimental 
  purposes 
  to 
  obtain 
  hybrids. 
  The 
  percentage 
  

   of 
  damaged 
  crops 
  on 
  some 
  fields 
  was 
  80-90 
  per 
  cent. 
  

  

  ■ 
  Aphis 
  gossypii, 
  Glov., 
  appeared 
  after 
  the 
  beginning 
  of 
  May. 
  At 
  

   first 
  only 
  small 
  colonies 
  of 
  winged 
  and 
  wingless 
  specimens 
  were 
  found, 
  

   but 
  after 
  June, 
  the 
  numbers 
  grew 
  rapidly. 
  The 
  progeny 
  of 
  winged 
  

   individuals 
  were 
  of 
  a 
  yellowish 
  or 
  brownish-green 
  colour 
  and 
  occupied 
  

   the 
  lower 
  sides 
  of 
  the 
  leaves 
  ; 
  those 
  of 
  wingless 
  parents 
  were 
  blackish- 
  

   brown 
  and 
  rested 
  mostly 
  on 
  the 
  stalks 
  and 
  buds 
  of 
  the 
  cotton 
  plants. 
  

   From 
  the 
  beginning 
  of 
  July 
  the 
  migration 
  of 
  the 
  aphids 
  began 
  and 
  

   then 
  the 
  injuries 
  caused 
  by 
  them 
  became 
  obvious. 
  The 
  injured 
  

   plants 
  had 
  an 
  unnatural, 
  shining 
  appearance. 
  The 
  author 
  attributes 
  

   to 
  these 
  insects 
  the 
  dropping 
  off 
  of 
  the 
  buds 
  and 
  young 
  bolls, 
  which 
  is 
  

   usually 
  ascribed 
  to 
  the 
  influence 
  of 
  dry 
  winds 
  or 
  lack 
  of 
  water. 
  The 
  

   injuries 
  caused 
  by 
  aphids 
  also 
  favoured 
  the 
  growth 
  of 
  a 
  fungus 
  

   (Capnodium) 
  which 
  develops 
  on 
  their 
  excreta. 
  

  

  At 
  the 
  beginning 
  of 
  July, 
  the 
  author 
  discovered 
  on 
  cotton 
  some 
  

   predaceous 
  insects 
  which 
  destroyed 
  the 
  lice, 
  such 
  as 
  the 
  larvae 
  of 
  

   Syrphus, 
  Leucopis, 
  Chrysopa, 
  Coccinella 
  1 
  -punctata, 
  L., 
  C. 
  18'punctata, 
  

   Scop., 
  Adonia 
  variegata, 
  Goeze, 
  and 
  other 
  species 
  ; 
  also 
  a 
  Braconid 
  

   of 
  the 
  genus 
  Aphidius, 
  which 
  proved 
  very 
  effective 
  in 
  destroying 
  

   the 
  pests. 
  About 
  the 
  middle 
  of 
  July 
  some 
  new 
  enemies 
  appeared 
  

   in 
  the 
  form 
  of 
  larvae 
  of 
  Aphidoletes 
  and 
  of 
  Triphleps 
  albidi- 
  

   pennis, 
  Rent., 
  and 
  a 
  parasite, 
  of 
  the 
  family 
  Pteromalidae, 
  replaced 
  

   the 
  Braconid. 
  Each 
  female 
  of 
  Aphidius 
  in 
  captivity 
  attacked 
  only 
  

   3 
  to 
  4 
  aphids 
  and 
  infested 
  only 
  the 
  wingless 
  forms. 
  The 
  adult 
  parasites 
  

   lived 
  for 
  a 
  week 
  in 
  captivity 
  before 
  ovipositing, 
  being 
  fed 
  on 
  honey. 
  

   At 
  the 
  beginning 
  of 
  July 
  the 
  same 
  aphids 
  were 
  also 
  found 
  on 
  melons 
  

   and 
  pumpkins 
  when 
  these 
  plants 
  w^ere 
  situated 
  near 
  cotton 
  fields, 
  

   also 
  on 
  Hibiscus 
  trionum, 
  L., 
  a 
  weed 
  belonging 
  to 
  the 
  same 
  family 
  as 
  

   cotton. 
  The 
  activity 
  of 
  all 
  the 
  natural 
  enemies 
  effected 
  a 
  marked 
  

   decrease 
  in 
  the 
  numbers 
  of 
  the 
  lice, 
  and 
  by 
  the 
  middle 
  of 
  August 
  it 
  was 
  

   difficult 
  to 
  discover 
  specimens 
  near 
  Andijan, 
  although 
  round 
  Skobelev, 
  

   small 
  colonies 
  existed 
  even 
  in 
  September. 
  

  

  Besides 
  A. 
  gossypii, 
  another 
  aphid, 
  which 
  has 
  just 
  been 
  described 
  

   by 
  Mordwilko 
  and 
  named 
  Acyrthosyphon 
  gossypii, 
  Mordw., 
  was 
  found 
  

   on 
  cotton 
  ; 
  it 
  is 
  similar 
  to 
  Aphis 
  pisi, 
  being 
  distinguished 
  from 
  it, 
  

   amongst 
  other 
  characters, 
  by 
  its 
  longer 
  proboscis. 
  The 
  author 
  first 
  

   discovered 
  small 
  colonies 
  of 
  these 
  aphids, 
  consisting 
  of 
  wingless 
  vivi- 
  

   parous 
  females 
  and 
  larvae 
  of 
  various 
  ages, 
  on 
  the 
  29th 
  June 
  near 
  

   Andijan 
  ; 
  a 
  month 
  later 
  the 
  numbers 
  of 
  this 
  species 
  were 
  much 
  greater 
  

  

  