﻿605 
  

  

  and 
  not 
  in 
  another, 
  and 
  that 
  cultural 
  conditions 
  usually 
  increase 
  the 
  

   susceptibiUty 
  and 
  only 
  exceptionally 
  assist 
  the 
  immunity 
  of 
  the 
  Citrus 
  

   trees. 
  Any 
  increase 
  of 
  sugar 
  and 
  consequent 
  decrease 
  of 
  acidity 
  

   in 
  the 
  fruit 
  aggravates 
  the 
  attack. 
  A 
  bibHography 
  of 
  47 
  works 
  is 
  

   appended 
  to 
  this 
  paper. 
  

  

  VoLKART 
  (— 
  ). 
  Dommages 
  culturaux. 
  [Injury 
  to 
  Crops.] 
  — 
  Annuaire 
  

   agricole 
  de 
  la 
  Suisse, 
  Berne, 
  xv, 
  no. 
  1, 
  1914, 
  pp. 
  4-6. 
  [Received 
  

   30th 
  July 
  1914.] 
  

  

  The 
  following 
  notes 
  referring 
  to 
  insect 
  pests 
  are 
  taken 
  from 
  Dr. 
  

   Volkart's 
  report 
  in 
  this 
  pubhcation 
  of 
  the 
  " 
  Departement 
  federal 
  de 
  

   r 
  Agriculture," 
  which 
  report 
  covers 
  the 
  period 
  from 
  the 
  1st 
  March 
  

   1912 
  to 
  the 
  28th 
  February 
  1913. 
  Vines 
  suffered 
  only 
  sHghtly 
  from 
  

   Clysia 
  ambiguella, 
  but 
  Phylloxera 
  showed 
  an 
  increase 
  on 
  1911. 
  Fruit 
  

   trees 
  were 
  occasionally 
  attacked 
  by 
  Anthonomus 
  and 
  Hyponomeuta, 
  

   and 
  Cheimatobia 
  seemed 
  to 
  be 
  more 
  numerous. 
  

  

  GouQH 
  (Dr. 
  L. 
  H.). 
  The 
  Fumigation 
  of 
  Citrus 
  Trees. 
  — 
  Agric. 
  Jl. 
  of 
  

   ^gyp^f 
  Cairo, 
  iv, 
  no. 
  1, 
  June 
  1914, 
  pp. 
  17-29. 
  

  

  Citrus 
  trees 
  in 
  Egypt 
  are 
  Uable 
  to 
  the 
  attacks 
  of 
  Chrysomphalits 
  

   {Aspidiotus) 
  aonidum, 
  C. 
  aurantii 
  and 
  Icerya 
  purchasi. 
  Fumigation 
  

   is 
  chiefly 
  used 
  against 
  C. 
  aonidum, 
  which 
  is 
  the 
  most 
  destructive 
  of 
  

   the 
  citrus 
  pests 
  and 
  attacks 
  all 
  kinds 
  of 
  citrus 
  plants, 
  mangoes, 
  jasmine, 
  

   roses, 
  narcissus, 
  camehas, 
  vines, 
  eucalyptus, 
  Ficus 
  nitida 
  and 
  other 
  

   species 
  of 
  figs, 
  bananas, 
  soursops, 
  guavas, 
  ornamental 
  palms, 
  and 
  many 
  

   other 
  plants. 
  It 
  has 
  several 
  generations 
  during 
  the 
  year, 
  but 
  nearly 
  

   all 
  individuals 
  which 
  occur 
  in 
  winter 
  are 
  mature 
  and 
  lay 
  their 
  eggs 
  

   from 
  December 
  to 
  January. 
  

  

  Infection 
  is 
  so 
  easily 
  carried 
  by 
  dead 
  leaves 
  or 
  infested 
  fruit 
  that 
  

   fumigation 
  can 
  only 
  cleanse 
  an 
  attacked 
  tree 
  and 
  is 
  no 
  preventative 
  

   against 
  re-infection. 
  It 
  seems 
  impossible 
  to 
  fumigate 
  successfully 
  

   a 
  seriously 
  attacked 
  tree 
  in 
  one 
  season. 
  

  

  Additional 
  details 
  as 
  to 
  the 
  method 
  of 
  fumigating 
  [see 
  this 
  Review, 
  

   Ser. 
  A, 
  ii, 
  p. 
  103] 
  are 
  given. 
  For 
  every 
  tree, 
  the 
  volume 
  enclosed 
  by 
  

   the 
  fumigation 
  sheet 
  is 
  calculated 
  and 
  the 
  dosage 
  for 
  that 
  volume 
  

   found 
  by 
  reference 
  to 
  Woglum's 
  table 
  [Bull. 
  90, 
  U.S. 
  Bureau 
  of 
  

   Entomology.] 
  To 
  calculate 
  the 
  volume, 
  paint 
  a 
  black 
  Hne 
  across 
  

   the 
  sheet, 
  so 
  that 
  it 
  reaches 
  from 
  side 
  to 
  side 
  and 
  passes 
  through 
  the 
  

   centre 
  of 
  the 
  sheet. 
  Mark 
  the 
  centre 
  of 
  the 
  hne 
  by 
  a 
  large 
  black 
  

   circle 
  and 
  from 
  this 
  measure 
  off 
  equal 
  distances 
  in 
  feet 
  along 
  the 
  line. 
  

   To 
  calculate 
  the 
  height 
  of 
  the 
  tree, 
  note 
  what 
  figure 
  on 
  the 
  hne 
  hes 
  

   on 
  the 
  ground 
  on 
  each 
  side 
  of 
  the 
  tree 
  when 
  the 
  sheet 
  is 
  in 
  position. 
  

   The 
  sum 
  of 
  the 
  two 
  figures 
  is 
  that 
  which 
  must 
  be 
  used 
  in 
  calculating 
  

   the 
  dosage. 
  To 
  obtain 
  the 
  circumference 
  of 
  the 
  tree, 
  measure 
  round 
  

   the 
  foot 
  of 
  the 
  hanging 
  sheet 
  with 
  a 
  tape 
  measure. 
  

  

  AppHcations 
  for 
  fumigation, 
  which 
  is 
  only 
  carried 
  out 
  in 
  Egypt 
  

   by 
  the 
  Government, 
  must 
  be 
  made 
  to 
  the 
  Inspector 
  of 
  the 
  province. 
  

   Only 
  trees 
  under 
  13 
  feet 
  high 
  will 
  be 
  fumigated 
  ; 
  larger 
  trees 
  should 
  be 
  

   felled 
  and 
  burnt, 
  or 
  they 
  should 
  be 
  cut 
  down 
  to 
  5 
  or 
  6 
  feet 
  high, 
  stripped 
  

   of 
  their 
  leaves 
  and 
  treated 
  with 
  hme, 
  salt 
  and 
  sulphur 
  solution. 
  This 
  

   should 
  be 
  done 
  in 
  January 
  or 
  February. 
  

  

  