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  Macgillivray 
  (A. 
  D.). 
  The 
  Immature 
  Stages 
  of 
  the 
  Tenthredinoidea. 
  

   — 
  Canadian 
  Entomologist, 
  x\v, 
  no. 
  11, 
  Nov. 
  1913, 
  pp. 
  367-371. 
  

  

  A 
  general 
  account 
  of 
  the 
  larval 
  habits 
  of 
  the 
  various 
  famiUes 
  of 
  

   sawflies. 
  

  

  Mackie 
  (D. 
  B.). 
  The 
  Philippine 
  Locust 
  (Pachytylus 
  [Locusta] 
  migra- 
  

   toroides, 
  R. 
  & 
  F.) 
  ; 
  Natural 
  Influences 
  affecting 
  its 
  Propagation 
  

   and 
  jyistnhution.^Philijjpine 
  Agric. 
  Review, 
  Manila, 
  vi, 
  no. 
  11, 
  

   1913, 
  pp. 
  538-547, 
  2 
  pis. 
  

  

  The 
  chief 
  forces 
  which 
  operate 
  for 
  or 
  against 
  anv 
  species 
  may 
  be 
  

   stated 
  as 
  climate, 
  food 
  supply 
  and 
  enemies. 
  Climatic 
  influences 
  exert 
  

   the 
  greatest 
  check 
  on 
  locusts. 
  Cold 
  weather 
  causes 
  them 
  to 
  hibernate 
  

   for 
  extended 
  periods, 
  though 
  this 
  is 
  seldom 
  the 
  case 
  in 
  the 
  Philippines. 
  

   Winds 
  are 
  important 
  in 
  locust 
  distribution 
  and 
  control. 
  Moderate 
  

   winds 
  often 
  enable 
  swarms 
  to 
  make 
  long, 
  sustained 
  flights, 
  even 
  

   crossing 
  from 
  island 
  to 
  island, 
  as 
  from 
  Cebu 
  to 
  Negros. 
  High 
  winds 
  

   tend 
  to 
  keep 
  locusts 
  near 
  the 
  ground 
  and 
  to 
  prevent 
  extended 
  flights, 
  

   and 
  severe 
  winds 
  often 
  work 
  great 
  havoc 
  with 
  locust 
  swarms, 
  at 
  times 
  

   completely 
  annihilating 
  them. 
  Locusts 
  seldom 
  fly 
  during 
  rains. 
  

   The 
  results 
  of 
  a 
  typhoon 
  are 
  often 
  disastrous 
  to 
  the 
  swarm, 
  the 
  locusts 
  

   being 
  killed 
  in 
  large 
  numbers 
  by 
  the 
  vegetation 
  being 
  whipped 
  about 
  

   by 
  the 
  high 
  winds, 
  while 
  the 
  wings 
  of 
  the 
  adults 
  are 
  often 
  torn 
  to 
  such 
  

   an 
  extent 
  that 
  further 
  flight 
  is 
  impossible, 
  so 
  that 
  the 
  females 
  are 
  

   forced 
  to 
  lay 
  their 
  eggs 
  on 
  unsuitable 
  ground, 
  which 
  results 
  in 
  a 
  low 
  

   percentage 
  of 
  them 
  hatching. 
  Floods 
  are 
  important 
  as 
  locust 
  destroyers, 
  

   especially 
  when 
  large 
  areas 
  on 
  which 
  locusts 
  have 
  oviposited 
  

   become 
  flooded 
  and 
  quantities 
  of 
  silt 
  deposited 
  over 
  the 
  eggs 
  which 
  

   effectually 
  prevents 
  the 
  hoppers 
  from 
  emerging. 
  Drought 
  seems 
  to 
  

   exert 
  a 
  powerful 
  influence 
  in 
  the 
  increase 
  of 
  the 
  pest, 
  since 
  dry 
  weather 
  

   is 
  inimical 
  to 
  locust 
  parasites. 
  Drought 
  may 
  also 
  induce 
  migrations. 
  

   Lack 
  of 
  food 
  might 
  also 
  cause 
  the 
  migratory 
  instinct 
  to 
  assert 
  itself. 
  

   Locust 
  enemies 
  may 
  be 
  classed 
  as 
  predators, 
  parasites 
  and 
  diseases. 
  

   The 
  miportance 
  of 
  birds 
  as 
  locust 
  exterminators 
  cannot 
  be 
  too 
  strongly 
  

   emphasised; 
  and 
  numerous 
  mammals, 
  reptiles, 
  frogs, 
  etc. 
  and 
  predatory 
  

   insects 
  attack 
  almost 
  entirely 
  the 
  immature 
  insects 
  and 
  eggs. 
  Of 
  the 
  

   flies 
  present 
  in 
  the 
  Philippines, 
  the 
  Dexinae 
  have 
  never 
  been 
  bred 
  

   out, 
  but 
  have 
  been 
  noted 
  in 
  the 
  vicinity 
  of 
  swarnis. 
  The 
  Sarco- 
  

   PHAGINAE 
  are 
  known 
  to 
  parasitise 
  both 
  the 
  mature 
  and 
  young 
  locusts. 
  

   Two 
  species 
  of 
  Nematodes, 
  or 
  hair-worms, 
  representing 
  the 
  two 
  genera 
  

   Gordius 
  and 
  Mermis 
  have 
  been 
  found 
  in 
  the 
  Philippine 
  locusts, 
  the 
  

   former 
  breeding 
  in 
  water, 
  while 
  the 
  latter 
  is 
  terrestrial. 
  The 
  eggs 
  are 
  

   deposited 
  in 
  water 
  or 
  on 
  the 
  ground 
  and 
  the 
  young 
  crawl 
  up 
  the 
  vege- 
  

   tation, 
  reaching 
  the 
  host 
  through 
  the 
  mouth 
  with 
  food, 
  and 
  undergoing 
  

   transformation 
  in 
  the 
  body 
  cavity 
  of 
  the 
  locust. 
  These 
  parasites 
  

   are 
  probably 
  of 
  little 
  economic 
  importance 
  as 
  locust 
  destroyers. 
  The 
  

   red 
  locust 
  mites, 
  so 
  far 
  as 
  is 
  known, 
  are 
  no 
  great 
  inconvenience 
  to 
  their 
  

   hosts. 
  The 
  possibility 
  of 
  controlling 
  locusts 
  through 
  the 
  agency 
  of 
  

   parasites 
  is 
  very 
  remote 
  since 
  the 
  percentage 
  of 
  parasitised 
  individuals 
  

   is 
  small. 
  The 
  fungous 
  disease 
  due 
  to 
  Empusa 
  grylli 
  has 
  been 
  known 
  

   to 
  infect 
  locusts, 
  but 
  it 
  is 
  impossible 
  to 
  cultivate 
  this 
  fungus 
  with 
  

   much 
  success 
  artificially 
  and 
  communicate 
  it 
  to 
  locust 
  swarms. 
  

   Experiments 
  to 
  test 
  the 
  effect 
  of 
  Coccohacillus 
  acridiorum, 
  D'Herelle, 
  

  

  