﻿101 
  

  

  principal 
  veins 
  being 
  left. 
  From 
  the 
  last-named 
  locality 
  it 
  has 
  spread 
  

   further 
  each 
  year. 
  

  

  Sahlberg 
  concludes 
  that 
  the 
  species 
  is 
  an 
  immigrant 
  from 
  the 
  east, 
  

   and 
  that 
  it 
  will 
  continue 
  to 
  spread 
  westwards, 
  and 
  eventually 
  reach 
  

   Sweden. 
  He 
  succeeded 
  in 
  finding 
  the 
  larva, 
  which, 
  in 
  July, 
  lives 
  in 
  

   the 
  same 
  manner 
  as 
  the 
  adult 
  does 
  in 
  spring 
  and 
  autumn. 
  A 
  detailed 
  

   diagnosis 
  and 
  figures 
  of 
  the 
  larva, 
  male, 
  female, 
  and 
  an 
  attacked 
  leaf 
  

   are 
  given. 
  

  

  Gas 
  Tar 
  and 
  Mealy 
  Bug. 
  Gardener's 
  Chronicle, 
  London, 
  liv, 
  nos. 
  1399, 
  

   1401, 
  1407, 
  1409, 
  18th 
  Oct., 
  1st 
  Nov., 
  6th 
  Dec, 
  13th 
  Dec. 
  1913, 
  

   pp. 
  279, 
  309, 
  407, 
  427. 
  

  

  Readers 
  of 
  the 
  " 
  Gardener's 
  Chronicle 
  " 
  have 
  communicated 
  the 
  

   results 
  of 
  their 
  experiences 
  with 
  gas 
  tar 
  as 
  a 
  means 
  of 
  combating 
  the 
  

   mealy 
  bug 
  (Pseudococcus 
  citri) 
  on 
  vines. 
  Mr. 
  A. 
  Shakelton, 
  Chard, 
  

   says 
  that 
  he 
  found 
  a 
  mixture 
  of 
  6 
  to 
  9 
  parts 
  of 
  clay 
  and 
  one 
  part 
  of 
  gas 
  

   tar 
  to 
  do 
  as 
  much 
  injury 
  to 
  the 
  vines 
  as 
  to 
  the 
  pest 
  ; 
  he 
  obtained 
  good 
  

   results 
  by 
  the 
  use 
  of 
  Gishurst 
  compound. 
  Mr. 
  J. 
  Whytock 
  upholds 
  the 
  

   use 
  of 
  a 
  mixture 
  of 
  clay 
  and 
  tar, 
  finding 
  that 
  it 
  destroys 
  the 
  pest 
  without 
  

   injuring 
  the 
  vines 
  ; 
  the 
  varieties 
  of 
  vine 
  grown 
  by 
  him 
  were 
  Mrs. 
  

   Pince, 
  Lady 
  Hutt, 
  Gus. 
  Colman, 
  and 
  Appley 
  Towers. 
  Mr. 
  Singleton 
  

   Oxfordshire, 
  says 
  that 
  the 
  use 
  of 
  a 
  mixture 
  of 
  gas 
  tar 
  and 
  clay 
  in 
  the 
  

   above 
  proportions 
  caused 
  complete 
  failure 
  of 
  the 
  crop 
  of 
  Black 
  Ham- 
  

   burgh 
  grapes, 
  but 
  he 
  used 
  it 
  successfully 
  in 
  the 
  case 
  of 
  varieties 
  such 
  

   as 
  Lady 
  DoT;Maes 
  and 
  Black 
  Alicante. 
  "J. 
  H. 
  Y." 
  gave 
  up 
  the 
  use 
  of 
  

   all 
  such 
  methods 
  as 
  painting 
  with 
  tar 
  in 
  favour 
  of 
  fumigation 
  with 
  

   hydrocyanic 
  acid, 
  which, 
  according 
  to 
  him, 
  is 
  entirely 
  satisfactory, 
  

   completely 
  kilHng 
  the 
  pest 
  without 
  injury 
  to 
  the 
  vine 
  or 
  any 
  other 
  

   plant 
  in 
  the 
  house 
  (except 
  Tradescantia). 
  He 
  also 
  found 
  the 
  gas 
  

   equally 
  successful 
  in 
  killing 
  brown 
  scale 
  (Lecanhnn 
  persicae, 
  Geofi.) 
  

   on 
  peach 
  trees. 
  

  

  Glaser 
  (R. 
  W.) 
  and 
  Chapman 
  (J. 
  W.)- 
  The 
  Wilt 
  Disease 
  of 
  Gipsy 
  

   Moth 
  Caterpillars. 
  — 
  Jl. 
  Econ. 
  Entom., 
  Concord, 
  vi, 
  no. 
  6, 
  Dec. 
  

   1913, 
  pp. 
  479-488. 
  

  

  In 
  August 
  1912, 
  the 
  authors 
  published 
  a 
  paper 
  in 
  Science 
  entitled 
  : 
  

   *' 
  Studies 
  on 
  the 
  Wilt 
  Disease 
  or 
  Flacherie 
  of 
  the 
  Gipsy 
  Moth." 
  [See 
  

   also 
  this 
  Review, 
  Ser. 
  A. 
  i, 
  pp. 
  33-36.] 
  More 
  extensive 
  observations 
  

   and 
  experiments 
  conducted 
  during 
  the 
  past 
  year 
  have 
  led 
  them 
  to 
  

   modify 
  some 
  of 
  their 
  original 
  views 
  concerning 
  this 
  disease. 
  The 
  

   conclusions 
  drawn 
  from 
  the 
  first 
  series 
  of 
  observations 
  concerning 
  the 
  

   mode 
  of 
  infection 
  and 
  general 
  pathology 
  were, 
  on 
  the 
  whole, 
  correct, 
  

   but 
  the 
  etiological 
  connection 
  of 
  a 
  micrococcus 
  with 
  the 
  disease 
  was 
  

   not 
  so 
  well 
  grounded. 
  The 
  micrococcus 
  described 
  in 
  1912, 
  and 
  beHeved 
  

   to 
  be 
  connected 
  mth 
  the 
  wilt 
  disease, 
  has 
  proved 
  to 
  be 
  a 
  casual 
  

   intestinal 
  parasite. 
  The 
  reason 
  for 
  eliminating 
  this 
  organism 
  

   (Gyrococcus 
  flaccidifex) 
  from 
  the 
  possible 
  excitors 
  of 
  the 
  disease 
  are 
  the 
  

   following 
  : 
  If 
  smears 
  were 
  made 
  from 
  caterpillars 
  dead 
  but 
  a 
  short 
  

   time, 
  no 
  bacteria 
  could 
  be 
  found. 
  Cultures 
  made 
  from 
  such 
  cater- 
  

  

  