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  infected 
  soil 
  failed, 
  but 
  it 
  was 
  found 
  not 
  to 
  lose 
  its 
  pathogenicity 
  after 
  

   existing 
  over 
  a 
  year 
  under 
  artificial 
  cultivation. 
  It 
  is 
  concluded 
  that 
  

   there 
  is 
  much 
  to 
  be 
  hoped 
  for 
  in 
  the 
  use 
  of 
  this 
  organism 
  in 
  combating 
  

   these 
  very 
  serious 
  pests 
  in 
  the 
  U.S.A. 
  and 
  the 
  West 
  Indies. 
  The 
  

   paper 
  concludes 
  with 
  a 
  list 
  of 
  29 
  works 
  referred 
  to. 
  

  

  ZwEiGELT 
  (F.). 
  Die 
  Maikafer 
  in 
  der 
  Bukowina 
  und 
  die 
  ausseren 
  

   Bedingungen 
  fflr 
  ihre 
  Verbreitung 
  in 
  Mitteleuropa. 
  [Cockchafers 
  in 
  

   Bukovina 
  and 
  the 
  external 
  conditions 
  for 
  their 
  distribution 
  

   in 
  Central 
  Europe.] 
  — 
  Naturwiss. 
  Zeitschr.f. 
  Forst- 
  u. 
  Landwirtsch., 
  

   Stuttgart, 
  xii, 
  nos. 
  6-7, 
  June-July 
  1914, 
  pp. 
  265-291, 
  329-344, 
  

   3 
  sketch 
  maps. 
  

  

  Both 
  Melolontha 
  hippocastani 
  and 
  M. 
  melolontha 
  occur 
  in 
  Bukovina, 
  

   the 
  latter 
  species 
  predominating 
  in 
  about 
  one-quarter 
  of 
  the 
  province 
  

   in 
  the 
  north-east, 
  especially 
  in 
  the 
  Czernowitz 
  district. 
  M. 
  hippo- 
  

   castani 
  prevails 
  in 
  an 
  area 
  of 
  about 
  equal 
  extent 
  lying 
  between 
  the 
  

   one 
  mentioned 
  above 
  and 
  the 
  south-western 
  half 
  of 
  Bukovina, 
  which 
  

   is 
  uninfested. 
  This 
  species 
  appears 
  about 
  the 
  end 
  of 
  April, 
  while 
  

   M. 
  melolontha 
  only 
  appears 
  in 
  May, 
  and 
  towards 
  the 
  end 
  of 
  that 
  month 
  

   in 
  the 
  colder 
  regions. 
  Even 
  in 
  the 
  warmest 
  locaUties 
  these 
  beetles 
  

   occur 
  later 
  than 
  in 
  Lower 
  Austria. 
  Observations 
  made 
  both 
  there 
  

   and 
  in 
  Bukovina 
  show 
  that 
  M. 
  melolontha 
  is 
  more 
  plentiful 
  in 
  the 
  

   warm 
  hill-lands 
  and 
  plains, 
  whilst 
  M. 
  hippocastani 
  prevails 
  on 
  the 
  

   hills 
  on 
  account 
  of 
  its 
  greater 
  resistance 
  to 
  unfavourable 
  climatic 
  

   influences, 
  though 
  where 
  the 
  latter 
  are 
  very 
  marked 
  it 
  loses 
  its 
  economic 
  

   importance. 
  Though 
  very 
  abundant, 
  only 
  one 
  beech 
  was 
  found 
  to 
  be 
  

   injured 
  to 
  every 
  four 
  oaks 
  and 
  six 
  willows. 
  Poplars, 
  horse-chestnuts, 
  

   alders, 
  maples 
  and 
  lime-trees 
  were 
  also 
  attacked. 
  Stone-fruit 
  suffered 
  

   considerably, 
  the 
  German 
  plum, 
  cherry 
  and 
  walnut 
  being 
  most 
  injured. 
  

   Apples 
  were 
  little 
  attacked 
  and 
  pears 
  still 
  less. 
  Amongst 
  field 
  crops, 
  

   potatoes, 
  maize, 
  clover, 
  sugar- 
  and 
  fodder-beets 
  were 
  attacked 
  by 
  

   the 
  larvae, 
  especially 
  the 
  first-named. 
  No 
  damage 
  to 
  vines 
  is 
  reported, 
  

   probably 
  owing 
  to 
  the 
  restricted 
  vine 
  cultivation. 
  The 
  severity 
  and 
  

   extent 
  of 
  the 
  attacks 
  of 
  both 
  larvae 
  and 
  adults 
  is 
  generally 
  independent 
  

   of 
  the 
  predominance 
  of 
  a 
  given 
  field-crop, 
  though 
  certain 
  favourite 
  

   food-plants 
  exist. 
  Control 
  of 
  the 
  larvae 
  was 
  limited 
  to 
  collection 
  

   during 
  ploughing, 
  whilst 
  in 
  some 
  instances 
  poultry 
  were 
  allowed 
  to 
  

   follow 
  the 
  plough. 
  The 
  practice 
  of 
  using 
  pigs 
  for 
  this 
  work 
  should 
  be 
  

   abandoned, 
  owing 
  to 
  the 
  danger 
  of 
  parasitic 
  intestinal 
  infestation 
  

   [see 
  this 
  Review, 
  Ser. 
  A, 
  ii, 
  p. 
  122]. 
  To 
  destroy 
  the 
  adults 
  when 
  caught, 
  

   carbon 
  bisulphide 
  is 
  recommended 
  at 
  a 
  dose 
  of 
  3 
  J 
  oz. 
  per 
  4 
  cubic 
  feet 
  

   of 
  space 
  filled 
  with 
  beetles, 
  to 
  be 
  applied 
  for 
  12 
  hours 
  at 
  least. 
  

   Eoughly 
  2J 
  million 
  beetles 
  were 
  caught 
  in 
  1912 
  in 
  Bukovina, 
  while 
  

   in 
  Lower 
  Austria 
  600 
  times 
  as 
  many 
  were 
  captured 
  in 
  the 
  same 
  

   period, 
  one 
  reason 
  for 
  the 
  difference 
  being 
  the 
  lack 
  of 
  organised 
  

   control 
  in 
  Bukovina. 
  

  

  Climate 
  plays 
  a 
  most 
  important 
  role 
  in 
  the 
  distribution 
  of 
  cock- 
  

   chafers, 
  and 
  the 
  insects 
  only 
  become 
  a 
  pest 
  in 
  regions 
  where 
  high 
  

   average 
  annual 
  temperatures 
  prevail, 
  together 
  with 
  the 
  consequent 
  

   scanty 
  precipitation. 
  Where 
  the 
  soil 
  is 
  dry, 
  warm, 
  deep 
  and 
  rich 
  

   in 
  food 
  material 
  the 
  conditions 
  are 
  most 
  favourable 
  to 
  these 
  insects. 
  

   The 
  paper 
  concludes 
  with 
  a 
  bibhography 
  of 
  nine 
  works. 
  

  

  