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  easily 
  accessible 
  than 
  tall 
  coconut 
  trees. 
  It 
  is 
  apparently 
  fatal 
  to 
  

   young 
  coconut 
  trees 
  suffering 
  from 
  drought 
  or 
  from 
  unsuitable 
  soil, 
  

   and 
  its 
  presence 
  is 
  clearly 
  noticeable 
  at 
  a 
  distance 
  by 
  the 
  spotted 
  

   appearance 
  of 
  the 
  leaves. 
  It 
  spreads 
  quite 
  as 
  easily 
  in 
  wet 
  as 
  in 
  dry 
  

   years, 
  and 
  the 
  young 
  leaves 
  should 
  be 
  burned 
  or 
  scorched 
  with 
  quite 
  

   a. 
  much 
  care 
  as 
  the 
  older 
  ones. 
  

  

  Coccus 
  hesperidum 
  and 
  Eucalymnatus 
  tessellatus 
  have 
  been 
  found 
  to 
  

   infest 
  leaves 
  of 
  the 
  Water 
  Hyacinth 
  (Eichornia 
  crassipes). 
  The 
  scale- 
  

   insects 
  are 
  nearly 
  always 
  accompanied 
  by 
  ants, 
  the 
  commonest 
  of 
  

   which, 
  Technomyrmex 
  albipes^ 
  has 
  been 
  studied, 
  especially 
  as 
  the 
  

   species 
  has 
  also 
  become 
  a 
  common 
  household 
  pest. 
  These 
  black 
  ants 
  

   are 
  supposed 
  to 
  have 
  been 
  introduced 
  in 
  1904 
  from 
  Ceylon 
  in 
  a 
  con- 
  

   signment 
  of 
  coconut, 
  cacao, 
  nutmeg 
  and 
  Hevea 
  rubber 
  seedhngs, 
  

   which 
  arrived 
  by 
  H.M.S. 
  " 
  Merhn," 
  but 
  there 
  is 
  abundant 
  proof 
  that 
  

   they 
  are 
  indigenous, 
  as 
  they 
  were 
  described 
  as 
  far 
  back 
  as 
  1861 
  by 
  

   Smith, 
  having 
  been 
  found 
  in 
  a 
  consignment 
  of 
  palms 
  received 
  at 
  

   Kew 
  from 
  the 
  Seychelles. 
  It 
  was 
  not, 
  however, 
  until 
  after 
  1906 
  that 
  

   they 
  became 
  household 
  pests 
  nearly 
  everywhere 
  in 
  Victoria, 
  and 
  this 
  

   fact 
  can 
  only 
  be 
  accounted 
  for 
  by 
  the 
  increase 
  of 
  scale-insects, 
  

   which, 
  after 
  the 
  droughts 
  of 
  1904, 
  obtained 
  a 
  strong 
  hold 
  and 
  caused 
  

   the 
  destruction 
  of 
  most 
  of 
  the 
  Citrus, 
  Hibiscus 
  and 
  Liberian 
  coffee 
  

   plants 
  growing 
  in 
  the 
  colony. 
  In 
  Mahe 
  the 
  spread 
  of 
  the 
  ants 
  has 
  

   been 
  estimated 
  at 
  about 
  1 
  mile 
  per 
  annum 
  and 
  w^as 
  more 
  or 
  less 
  

   coincident 
  with 
  the 
  spread 
  of 
  the 
  scale-insects. 
  With 
  the 
  exception 
  

   of 
  La 
  Digue, 
  North 
  Island, 
  Marianne 
  and 
  Aride 
  Island 
  in 
  the 
  Mahe 
  

   group, 
  Aldabra, 
  Astove 
  and 
  Cosmoledo 
  in 
  the 
  Aldabra 
  group, 
  and 
  the 
  

   Amirantes, 
  all 
  the 
  other 
  islands 
  are 
  infested, 
  and 
  if 
  no 
  measures 
  are 
  

   taken 
  to 
  stop 
  the 
  distribution 
  of 
  ants 
  carried 
  in 
  suppUes 
  purchased 
  

   from 
  ships, 
  it 
  will 
  not 
  be 
  long 
  before 
  these 
  insects 
  have 
  invaded 
  the 
  

   whole 
  archipelago, 
  as 
  there 
  is 
  no 
  chmatic 
  factor 
  which 
  can 
  hinder 
  

   their 
  dispersal. 
  They 
  have 
  not, 
  however, 
  spread 
  above 
  1,500 
  feet, 
  

   though 
  it 
  is 
  not 
  yet 
  known 
  whether 
  this 
  is 
  due 
  to 
  climate 
  or 
  to 
  the 
  

   presence 
  of 
  parasites. 
  

  

  These 
  ants 
  are 
  principally 
  troublesome 
  owing 
  to 
  the 
  protection 
  they 
  

   afford 
  to 
  countless 
  numbers 
  of 
  scale-insects, 
  with 
  the 
  following 
  

   species 
  of 
  which 
  they 
  are 
  associated 
  : 
  — 
  Icerya 
  seychellarum, 
  Eucaly^n- 
  

   natiis, 
  Coccus 
  longulus, 
  Coccus 
  viridis, 
  Pseudococcus 
  (Dactylopius) 
  

   citri, 
  P. 
  virgatus, 
  Asterolecanium 
  epidendri, 
  Pulvinaria 
  psidii, 
  P. 
  anti- 
  

   goni, 
  Vinsonia 
  stellifera, 
  Chrysomphalus 
  aonidum. 
  They 
  seem 
  not 
  to 
  

   care 
  in 
  the 
  same 
  degree 
  for 
  : 
  — 
  Chionaspis 
  inday, 
  Hemichionaspis 
  

   minor, 
  H. 
  aspidistrae, 
  Aulacaspis 
  (Diaspis) 
  pentagona, 
  Mytilaspis 
  

   auriculata, 
  Saissetia 
  nigra 
  (Lecanium 
  nigrum), 
  Asterolecanium 
  ham- 
  

   busae, 
  which 
  are 
  quite 
  as 
  common 
  insects 
  as 
  those 
  in 
  the 
  preceding 
  

   hst, 
  but 
  they 
  have 
  to 
  become 
  strongly 
  estabhshed 
  on 
  certain 
  species 
  of 
  

   plants 
  before 
  the 
  ants 
  are 
  attracted 
  by 
  them. 
  These 
  ants 
  and 
  their 
  

   habits 
  are 
  described 
  at 
  length, 
  and 
  the 
  importance 
  of 
  their 
  destruc- 
  

   tion 
  as 
  the 
  propagators 
  of 
  scale-insects 
  is 
  strongly 
  insisted 
  upon. 
  

   Nests 
  may 
  be 
  destroyed 
  by 
  spraying 
  with 
  soda-resin 
  solution 
  and 
  

   by 
  the 
  use 
  of 
  trap 
  boxes, 
  the 
  contents 
  of 
  which 
  are 
  periodically 
  burned. 
  

   [See 
  this 
  Review, 
  Ser. 
  A, 
  i, 
  p. 
  328.] 
  

  

  The 
  Rhinoceros 
  beetle 
  in 
  the 
  Seychelles 
  interferes 
  greatly 
  ^vith 
  the 
  

   growth 
  of 
  young 
  coconut 
  trees 
  and 
  all 
  palms 
  are 
  attacked 
  with 
  the 
  

  

  