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  THE 
  DOMESTIC 
  BREEDING 
  MOSQUITOS 
  OF 
  THE 
  NORTHERN 
  

   TERRITORIES 
  OF 
  THE 
  GOLD 
  COAST. 
  

   By 
  A. 
  Ingram, 
  M.D., 
  C.M 
  4 
  , 
  

  

  West 
  African 
  Medical 
  Staff. 
  

  

  The 
  work 
  of 
  Dr. 
  J. 
  J. 
  Simpson 
  (Bull. 
  Ent. 
  Res. 
  v, 
  pp. 
  1-36 
  and 
  Bull. 
  Ent. 
  Res. 
  viii, 
  

   pp. 
  193-214) 
  has 
  added 
  largely 
  to 
  the 
  knowledge 
  of 
  the 
  bionomics 
  of 
  the 
  larger 
  blood- 
  

   sucking 
  insects 
  of 
  the 
  Gold 
  Coast, 
  especially 
  of 
  the 
  Northern 
  Territories 
  of 
  the 
  Colony, 
  

   yet 
  up 
  to 
  the 
  present 
  time, 
  with 
  the 
  exception 
  of 
  the 
  records 
  obtained 
  from 
  one 
  or 
  

   two 
  stations, 
  singularly 
  little 
  is 
  known 
  with 
  regard 
  to 
  the 
  distribution 
  in 
  the 
  Northern 
  

   Territories 
  of 
  the 
  smaller 
  blood-sucking 
  insects 
  such 
  as 
  mosquitos 
  and 
  " 
  sandflies." 
  

  

  It 
  was 
  therefore 
  determined, 
  when 
  instructions 
  were 
  received 
  from 
  the 
  Hon. 
  

   Principal 
  Medical 
  Officer 
  to 
  accompany 
  him 
  on 
  a 
  tour 
  round 
  the 
  Northern 
  Territories 
  

   with 
  a 
  view 
  to 
  determining 
  the 
  prevalence 
  of 
  S. 
  fasciata, 
  F., 
  to 
  take 
  the 
  opportunity 
  

   of 
  recording 
  the 
  distribution 
  of 
  as 
  many 
  other 
  species 
  of 
  mosquitos 
  and 
  " 
  sandflies 
  ' 
  

   as 
  possible. 
  

  

  The 
  tour 
  occupied 
  about 
  three 
  months, 
  the 
  Northern 
  Territories 
  being 
  entered 
  on 
  

   the 
  3rd 
  May 
  and 
  left 
  on 
  the 
  2nd 
  August 
  1918. 
  It 
  must 
  be 
  confessed 
  that 
  the 
  results 
  

   obtained 
  were 
  disappointing 
  ; 
  this 
  is 
  to 
  be 
  attributed 
  (a) 
  to 
  the 
  exceptional 
  dryness 
  

   of 
  the 
  season, 
  (b) 
  to 
  the 
  short 
  halts 
  — 
  less 
  than 
  24 
  hours 
  — 
  made 
  at 
  the 
  majority 
  of 
  

   places, 
  and 
  (c) 
  to 
  the 
  difficulty 
  of 
  hatching 
  adult 
  mosquitos 
  from 
  larvae 
  and 
  pupae 
  

   " 
  en 
  route," 
  few 
  larvae 
  and 
  fewer 
  pupae 
  surviving 
  the 
  continous 
  jolting 
  to 
  which 
  the 
  

   water 
  in 
  the 
  breeding 
  jars 
  was 
  submitted 
  when 
  borne 
  on 
  the 
  head 
  of 
  a 
  carrier. 
  So 
  

   far 
  as 
  the 
  commoner 
  mosquitos 
  were 
  concerned 
  the 
  death 
  in 
  the 
  pots 
  of 
  their 
  larvae 
  

   or 
  pupae 
  was 
  unimportant, 
  as 
  identities 
  could 
  generally 
  be 
  established 
  from 
  an 
  

   examination 
  of 
  the 
  dead 
  larvae 
  or 
  pupae 
  ; 
  but 
  unfortunately 
  on 
  one 
  or 
  two 
  occasions 
  

   larvae 
  or 
  pupae 
  which 
  were 
  not 
  known 
  were 
  collected 
  and 
  as 
  these 
  succumbed 
  without 
  

   hatching 
  the 
  identity 
  of 
  their 
  imagines 
  is 
  yet 
  to 
  seek. 
  

  

  A 
  routine 
  plan 
  Of 
  working 
  was 
  adopted 
  and 
  adhered 
  to 
  as 
  closely 
  as 
  possible 
  

   throughout 
  the 
  tour. 
  A 
  visit 
  was 
  made 
  to 
  the 
  native 
  compounds 
  each 
  evening 
  

   between 
  5 
  and 
  6 
  o'clock 
  to 
  search 
  for 
  collections 
  of 
  water 
  containing 
  larvae 
  or 
  pupae 
  

   of 
  mosquitos 
  ; 
  when 
  these 
  were 
  found, 
  samples 
  of 
  the 
  contents 
  were 
  transferred 
  to 
  

   glass 
  jars 
  and 
  the 
  top 
  of 
  the 
  jars 
  covered 
  with 
  fine-meshed 
  gauze. 
  These 
  jars 
  were 
  

   carried 
  along 
  from 
  day 
  to 
  day 
  till 
  adult 
  mosquitos 
  had 
  hatched 
  or 
  the 
  larvae 
  and 
  

   pupae 
  had 
  died. 
  In 
  the 
  case 
  of 
  small 
  villages 
  every 
  compound 
  was 
  visited, 
  but 
  in 
  

   the 
  case 
  of 
  the 
  larger 
  villages 
  or 
  where 
  the 
  individual 
  compounds 
  were 
  several 
  

   hundred 
  yards 
  apart, 
  as 
  in 
  the 
  Frafra, 
  Grunshi 
  and 
  Lobi 
  countries, 
  only 
  half 
  a 
  dozen 
  

   of 
  the 
  compounds 
  nearest 
  to 
  the 
  Rest 
  House 
  were 
  examined. 
  

  

  Wees 
  growing 
  in 
  close 
  proximity 
  to 
  the 
  Rest 
  Houses 
  were 
  scrutinised 
  carefully 
  

   for 
  " 
  rot 
  " 
  holes, 
  which 
  are 
  known 
  to 
  form 
  a 
  favourite 
  habitat 
  of 
  larvae 
  and 
  pupae 
  

   of 
  certain 
  mosquitos, 
  e.g.,Stegomyia. 
  The 
  walls 
  of 
  the 
  Rest 
  Houses 
  were 
  examined 
  

   each 
  day 
  for 
  Phlebotomies 
  and 
  every 
  evening 
  when 
  sitting 
  out 
  in 
  the 
  open 
  air 
  a 
  look 
  

   out 
  was 
  kept 
  for 
  Culicoides. 
  

  

  