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  more 
  or 
  less 
  morphological 
  separation. 
  A 
  very 
  complete 
  biblio- 
  

   graphy 
  is 
  given 
  and 
  the 
  structural 
  details 
  of 
  the 
  fly 
  and 
  its 
  larva 
  are 
  

   fully 
  illustrated. 
  

  

  Barker 
  (B. 
  T. 
  P.) 
  & 
  Gimingham 
  (C. 
  T.). 
  The 
  Action 
  of 
  Bordeaux 
  

   Mixture 
  on 
  Plants. 
  — 
  Ann. 
  App. 
  Biol., 
  Cambridge 
  Univ. 
  Press, 
  i, 
  

   no. 
  1, 
  May 
  1914, 
  pp. 
  9-21, 
  6 
  figs. 
  

  

  The 
  authors 
  have 
  made 
  a 
  number 
  of 
  observations 
  on 
  the 
  effects 
  of 
  

   Bordeaux 
  mixture 
  upon 
  the 
  tissues 
  of 
  plants 
  with 
  which 
  it 
  comes 
  into 
  

   contact 
  in 
  the 
  process 
  of 
  spraying. 
  Injury 
  to 
  foliage 
  by 
  Bordeaux 
  

   mixture 
  has 
  been 
  the 
  subject 
  of 
  a 
  good 
  deal 
  of 
  investigation, 
  especially 
  

   in 
  America. 
  It 
  was 
  found 
  very 
  difiicult 
  to 
  obtain 
  any 
  number 
  of 
  

   apple 
  leaves 
  which 
  were 
  quite 
  free 
  from 
  injury 
  of 
  some 
  sort, 
  and 
  it 
  was. 
  

   therefore 
  necessary 
  to 
  grow 
  foliage 
  specially 
  protected 
  from 
  liability 
  

   to 
  injury. 
  As 
  the 
  result 
  of 
  investigations 
  it 
  appears 
  that 
  cells 
  with 
  

   readily 
  permeable 
  walls 
  (such 
  as 
  germ 
  tubes 
  of 
  fungus 
  spores, 
  root 
  

   hairs, 
  the 
  interior 
  tissues 
  of 
  leaves, 
  etc.) 
  exert 
  a 
  considerable 
  solvent 
  

   action 
  on 
  the 
  particles 
  of 
  the 
  copper 
  compounds 
  with 
  which 
  they 
  come 
  

   in 
  contact, 
  resulting 
  in 
  rapid 
  absorption 
  of 
  the 
  dissolved 
  copper, 
  

   followed 
  by 
  death 
  of 
  the 
  cells. 
  In 
  the 
  case 
  of 
  injured 
  fohage 
  such 
  

   action 
  results 
  in 
  scorching. 
  

  

  The 
  amount 
  of 
  inter-action 
  between 
  other 
  types 
  of 
  cells 
  and 
  the 
  

   copper 
  compounds 
  is 
  determined 
  by 
  the 
  nature 
  of 
  the 
  cell 
  wall. 
  Direct 
  

   absorption 
  of 
  copper 
  by 
  leaves 
  of 
  certain 
  types 
  takes 
  place 
  with 
  or 
  

   without 
  local 
  injury, 
  depending 
  on 
  the 
  nature 
  of 
  the 
  leaf 
  surface. 
  

   Transference 
  of 
  the 
  absorbed 
  copper 
  to 
  other 
  parts 
  of 
  the 
  plant 
  may 
  

   follow. 
  Copper 
  may 
  be 
  absorbed 
  through 
  the 
  roots 
  of 
  certain 
  plants, 
  

   (potatoes, 
  beans) 
  with 
  local 
  injury 
  to 
  the 
  root. 
  This 
  absorbed 
  copper 
  

   can 
  be 
  transferred 
  to 
  parts 
  of 
  the 
  plants 
  above 
  ground 
  without 
  injury 
  

   to 
  the 
  cells 
  through 
  which 
  it 
  passes. 
  

  

  Theobald 
  (F. 
  V.). 
  Notes 
  on 
  the 
  Green 
  Spruce 
  Aphis 
  {Aphis 
  abietinay 
  

   Walk.). 
  — 
  Ann. 
  App. 
  Biol., 
  Cambridge 
  Univ. 
  Press, 
  i, 
  no. 
  1, 
  May 
  

   1914, 
  pp. 
  23-36, 
  10 
  figs. 
  

  

  During 
  1913 
  a 
  very 
  severe 
  attack 
  of 
  the 
  Aphis 
  described 
  by 
  Walker 
  

   in 
  1849 
  as 
  Aphis 
  abietina 
  took 
  place 
  on 
  spruce 
  trees. 
  The 
  insect 
  is 
  

   described 
  and 
  figured, 
  and 
  a 
  hst 
  is 
  given 
  of 
  locahties 
  in 
  which 
  it 
  has 
  

   been 
  found 
  in 
  the 
  United 
  Kingdom. 
  The 
  trees 
  of 
  the 
  genus 
  Picea 
  are 
  

   unquestionably 
  its 
  normal 
  food-plants, 
  but 
  it 
  has 
  also 
  been 
  taken 
  by 
  

   the 
  author 
  on 
  Scots 
  pines 
  on 
  six 
  occasions 
  and 
  once 
  on 
  a 
  Weymouth 
  pine 
  

   at 
  Wye. 
  It 
  has 
  been 
  found 
  on 
  Picea 
  excelsa, 
  P. 
  sitchensis, 
  P. 
  pungens, 
  

   P. 
  engelmannii, 
  P. 
  nigra, 
  P. 
  alba, 
  P. 
  gigantea, 
  P. 
  rubra, 
  P. 
  morinda^ 
  

   P. 
  monstrosa, 
  P. 
  omorica, 
  P. 
  kosteriana, 
  P. 
  gleMre 
  [? 
  glehrii]. 
  P. 
  polita, 
  

   P. 
  hondoensis, 
  P. 
  alcoguiana 
  and 
  P. 
  alaskiana, 
  but 
  in 
  some 
  places 
  

   P. 
  omorica 
  appears 
  to 
  be 
  immune. 
  Speaking 
  generally, 
  the 
  Sitka 
  

   spruce 
  is 
  most 
  damaged, 
  but 
  this 
  is 
  not 
  always 
  the 
  case. 
  Two 
  

   markedly 
  different 
  effects 
  are 
  produced 
  by 
  this 
  aphis. 
  In 
  

   P. 
  sitchensis 
  the 
  damaged 
  needles 
  soon 
  fall, 
  and 
  complete 
  defohation. 
  

   results. 
  In 
  P. 
  excelsa 
  the 
  needles 
  turn 
  brown, 
  but 
  the 
  majority 
  

   remain 
  on 
  the 
  tree, 
  which 
  looks 
  as 
  if 
  it 
  has 
  been 
  scorched 
  by 
  fire. 
  

   P. 
  morinda 
  and 
  P. 
  glehire 
  [glehrii 
  ?] 
  are 
  only 
  partially 
  defohated, 
  

   though 
  this 
  is 
  not 
  the 
  case 
  with 
  P. 
  engelmannii 
  and 
  P. 
  kosteriana. 
  

  

  