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  Andrews 
  (E. 
  A.). 
  On 
  Insects. 
  Part 
  II. 
  — 
  Ind. 
  Tea 
  Assoc, 
  Scientific 
  

   Dejjt., 
  Quarterly 
  JL, 
  Calcutta, 
  1913, 
  pt. 
  2, 
  pp. 
  33-42. 
  

  

  In 
  the 
  course 
  of 
  this 
  article 
  the 
  following 
  formula 
  is 
  given 
  for 
  use 
  in 
  

   the 
  nursery 
  against 
  grasshoppers 
  suspected 
  of 
  injuring 
  the 
  young 
  tea 
  

   plants: 
  Lead 
  arsenate, 
  lib.; 
  jaggery, 
  5 
  lb. 
  ; 
  'water, 
  100 
  gallons. 
  

   Flooding 
  the 
  nursery 
  for 
  a 
  short 
  time, 
  say 
  half 
  a 
  day, 
  appears 
  to 
  be 
  a 
  

   practical 
  measure 
  against 
  crickets. 
  Another 
  niethod 
  of 
  dealing 
  with 
  

   them 
  is 
  by 
  means 
  of 
  poisoned 
  bait, 
  Lefroy's 
  formula 
  being 
  : 
  Husks 
  of 
  

   rice, 
  80 
  lb. 
  ; 
  white 
  arsenic, 
  2 
  lb. 
  ; 
  gur, 
  4 
  lb. 
  When 
  the 
  young 
  crickets 
  

   first 
  hatch, 
  they 
  stay 
  in 
  the 
  burrow, 
  but 
  after 
  a 
  few 
  days 
  emerge 
  and 
  

   begin 
  to 
  feed, 
  digging 
  fresh 
  burrows 
  for 
  themselves 
  every 
  night 
  ; 
  as 
  

   they 
  grow 
  older 
  they 
  dig 
  deeper, 
  and 
  eventually 
  adopt 
  a 
  permanent 
  

   burrow. 
  Crickets 
  do 
  great 
  damage 
  to 
  the 
  tea 
  plants, 
  cutting 
  off 
  the 
  

   tops 
  of 
  the 
  seedlings 
  and 
  dragging 
  them 
  to 
  their 
  burrows. 
  They 
  also 
  

   do 
  injury 
  to 
  jute, 
  indigo, 
  rice, 
  and 
  many 
  other 
  plants. 
  Owls 
  and 
  bats 
  

   consume 
  large 
  numbers 
  of 
  these 
  pests, 
  and 
  heavy 
  rains 
  drive 
  them 
  out 
  

   of 
  their 
  burrows 
  ; 
  when 
  this 
  happens 
  birds 
  destroy 
  great 
  quantities 
  

   of 
  them. 
  Digger 
  wasps 
  and 
  ants 
  are 
  also 
  to 
  be 
  reckoned 
  amongst 
  their 
  

   enemies. 
  

  

  Urich 
  (F. 
  W.). 
  The 
  Froghopper 
  Egg-Parasite 
  (Oligosita 
  giraulti, 
  

   Crawford) 
  and 
  its 
  colonisation 
  in 
  the 
  Cane 
  Fields. 
  — 
  Bd. 
  of 
  Agric, 
  

   Trinidad 
  and 
  Tobago, 
  Port- 
  of- 
  Spain, 
  Circ. 
  no. 
  11, 
  18th 
  Aug. 
  

   1913, 
  9 
  pp. 
  

  

  The 
  vermilion 
  froghopper 
  egg-parasite 
  {Oligosita 
  g'raulti, 
  Cwf.) 
  has 
  

   been 
  bred 
  from 
  grass 
  from 
  various 
  localities 
  in 
  Trinidad. 
  From 
  ex- 
  

   periments 
  it 
  is 
  found 
  that 
  the 
  most 
  suitable 
  stage 
  of 
  the 
  development 
  

   of 
  the 
  froghopper 
  egg 
  for 
  the 
  parasite 
  is 
  that 
  in 
  which 
  the 
  embryo 
  is 
  well 
  

   advanced, 
  and 
  that 
  the 
  larval 
  and 
  pupal 
  stages 
  of 
  the 
  parasite 
  take 
  

   from 
  22 
  to 
  41 
  days. 
  The 
  adult 
  parasite 
  is 
  very 
  active, 
  and 
  ever 
  search- 
  

   ing 
  for 
  froghopper 
  eggs, 
  passing 
  from 
  one 
  piece 
  of 
  grass 
  to 
  another 
  by 
  

   little 
  leaps. 
  The 
  multiplication 
  of 
  the 
  parasite 
  is 
  by 
  no 
  means 
  so 
  great 
  

   as 
  that 
  of 
  the 
  froghopper. 
  However, 
  the 
  eggs 
  of 
  the 
  latter 
  

   require 
  more 
  moisture 
  to 
  hatch 
  than 
  the 
  parasite 
  requires 
  for 
  its 
  

   development, 
  so 
  that 
  this 
  is 
  a 
  factor 
  greatly 
  to 
  the 
  advantage 
  of 
  the 
  

   parasite. 
  Another 
  important 
  factor 
  is 
  that 
  the 
  parasite 
  reproduces 
  

   parthenogenetically 
  and 
  a 
  female 
  is 
  ready 
  to 
  lay 
  one 
  hour 
  after 
  issuing 
  

   from 
  a 
  froghopper 
  egg. 
  Parasitism 
  of 
  froghopper 
  eggs 
  under 
  normal 
  

   conditions 
  is 
  probably 
  about 
  25 
  per 
  cent. 
  Colonisation 
  of 
  the 
  para- 
  

   sites 
  in 
  the 
  cane-fields 
  is 
  thought 
  to 
  be 
  best 
  carried 
  out 
  by 
  transferring 
  

   grass 
  yielding 
  parasites 
  by 
  cartloads 
  to 
  fields 
  harbouring 
  no 
  parasites. 
  

  

  Kershaw 
  (J. 
  C). 
  Froghoppers. 
  — 
  Bull. 
  Deft. 
  Agric, 
  Trinidad 
  and 
  

   Tobago, 
  Port-of- 
  Spain, 
  xii, 
  nos. 
  72 
  & 
  73, 
  Aug. 
  & 
  Sept. 
  1913, 
  pp. 
  

   3-12, 
  95-101, 
  3 
  pis. 
  

  

  The 
  growth 
  of 
  the 
  young 
  sugar-cane 
  could 
  be 
  hastened 
  by 
  a 
  fertiliser 
  

   and 
  the 
  plants 
  would 
  probably 
  hold 
  their 
  own 
  against 
  the 
  nymphs 
  of 
  

   the 
  froghopper 
  until 
  grown 
  too 
  large 
  to 
  suffer 
  much 
  damage. 
  Nitrolim, 
  

   a 
  valuable 
  and 
  fairly 
  cheap 
  fertiliser, 
  which 
  is 
  also 
  of 
  some 
  use 
  in 
  

   killing 
  the 
  nymphs, 
  is 
  therefore 
  worth 
  an 
  extended 
  trial. 
  The 
  planting 
  

   of 
  trees 
  and 
  shrubs 
  on 
  waste 
  land 
  adjoining 
  cane 
  fields 
  would 
  en- 
  

   courage 
  the 
  spread 
  of 
  the 
  tick 
  bird 
  (Crotophaga 
  ani) 
  and 
  other 
  useful 
  

  

  