﻿INVESTIGATIONS 
  INTO 
  THE 
  BIONOMICS 
  OF 
  GLOSSINA 
  PALPALIS.* 
  447 
  

  

  (3). 
  On 
  the 
  island 
  of 
  Bussi, 
  largely 
  sudd-bound, 
  but 
  previous 
  to 
  1909 
  separated 
  

   from 
  the 
  mainland 
  by 
  a 
  canoe 
  track 
  through 
  the 
  sudd, 
  no 
  leopard 
  formerly 
  occurred. 
  

   The 
  canoe 
  track 
  was 
  choked 
  by 
  sudd, 
  however, 
  and 
  leopards 
  crossed 
  it 
  soon 
  after 
  the 
  

   eastern 
  shore 
  of 
  the 
  island 
  was 
  depopulated. 
  In 
  October 
  1914 
  the 
  island 
  was 
  surveyed 
  

   for 
  game 
  and 
  inland 
  infestation 
  by 
  fly. 
  Nowhere 
  else 
  were 
  the 
  excreta 
  of 
  leopards 
  

   discovered 
  in 
  such 
  extraordinary 
  quantity, 
  and 
  examination 
  of 
  them 
  — 
  exact 
  figures 
  

   were 
  not 
  kept 
  — 
  disclosed 
  unmistakable 
  remains 
  of 
  either 
  situtunga 
  or 
  monkey 
  in 
  

   nearly 
  every 
  case. 
  No 
  other 
  traces 
  of 
  situtunga 
  were 
  found 
  on 
  the 
  island 
  except, 
  

   as 
  is 
  usual 
  on 
  the 
  mainland, 
  along 
  the 
  borders 
  of 
  the 
  sudd-fields. 
  There 
  was 
  no 
  

   inland 
  extension 
  to 
  the 
  infestation 
  by 
  fly, 
  which 
  was 
  fairly 
  dense 
  along 
  the 
  shore. 
  

  

  (4). 
  Zinga 
  Island 
  was 
  sudd-bound 
  like 
  Bussi, 
  and 
  like 
  it, 
  separated 
  from 
  the 
  main- 
  

   land 
  by 
  a 
  canoe 
  track. 
  It 
  was 
  said 
  by 
  the 
  natives 
  to 
  be 
  entirely 
  free 
  from 
  leopards. 
  

   Situtunga 
  increased 
  to 
  very 
  large 
  numbers, 
  as 
  on 
  the 
  Sesse 
  Islands, 
  and 
  extended 
  

   its 
  range 
  inland. 
  The 
  range 
  of 
  fly 
  was 
  also 
  extended 
  inland 
  up 
  to 
  at 
  least 
  1,000 
  yards. 
  

   In 
  exploring 
  the 
  island 
  for 
  inland 
  infestation 
  in 
  August 
  1915 
  fresh 
  excreta 
  of 
  leopard 
  

   were 
  found, 
  and 
  examination 
  of 
  the 
  old 
  canoe 
  track 
  showed 
  that 
  it 
  had 
  become 
  

   broadly 
  choked 
  with 
  sudd. 
  If 
  the 
  history 
  of 
  the 
  incursion 
  of 
  leopards 
  in 
  Bussi 
  is 
  

   repeated, 
  the 
  animals 
  should 
  become 
  very 
  numerous 
  by 
  about 
  1920 
  ; 
  situtunga 
  

   should 
  be 
  driven 
  back 
  into 
  the 
  protection 
  of 
  the 
  sudd-fields, 
  and 
  monkeys, 
  which 
  

   were 
  excessively 
  numerous 
  in 
  1915, 
  should 
  be 
  greatly 
  reduced 
  in 
  density. 
  

  

  (5). 
  At 
  no 
  point 
  on 
  the 
  mainland 
  has 
  situtunga 
  increased 
  to 
  much, 
  if 
  at 
  all, 
  beyond 
  

   its 
  former 
  density, 
  nor 
  has 
  it 
  extended 
  its 
  range 
  beyond 
  easy 
  reach 
  of 
  the 
  animals 
  

   from 
  the 
  protection 
  of 
  sudd-fields 
  and 
  marshes. 
  

  

  (6). 
  At 
  about 
  three 
  points 
  on 
  the 
  mainland 
  where 
  the 
  local 
  environment 
  affords 
  

   exceptionally 
  good 
  protection 
  to 
  bush-buck, 
  inland 
  extension 
  of 
  infestation 
  by 
  

   fly 
  corresponds 
  to 
  that 
  on 
  islands 
  where 
  leopard 
  is 
  absent 
  and 
  situtunga 
  has 
  increased 
  

   to 
  exceptional 
  density. 
  

  

  There 
  can 
  be 
  no 
  doubt 
  that 
  the 
  range 
  and 
  density 
  of 
  situtunga 
  are 
  controlled 
  by 
  

   the 
  leopard, 
  which 
  is 
  unable 
  to 
  harm 
  it 
  in 
  the 
  protection 
  afforded 
  by 
  sudd-fields 
  

   and 
  marshes, 
  but 
  which 
  hunts 
  it 
  assiduously 
  along 
  the 
  border 
  of 
  these 
  protected 
  

   precincts. 
  There 
  can 
  be 
  little 
  doubt 
  that 
  the 
  range 
  and 
  density 
  of 
  bush-buck 
  are 
  

   controlled 
  in 
  the 
  same 
  manner 
  ; 
  protection 
  in 
  its 
  case 
  being 
  provided 
  by 
  densely 
  

   tangled 
  thickets, 
  through 
  which 
  it 
  plunges 
  with 
  strange 
  facility, 
  and 
  within 
  which 
  

   no 
  large 
  animal 
  can 
  approach 
  it 
  without 
  betraying 
  itself. 
  

  

  Wherever 
  leopard 
  is 
  absent 
  and 
  situtunga 
  present 
  in 
  sufficient 
  density, 
  range 
  of 
  

   fly 
  is 
  extended 
  inland, 
  and 
  situtunga 
  has 
  increased 
  or 
  is 
  increasing 
  (if 
  present 
  at 
  all) 
  

   everywhere 
  that 
  leopard 
  is 
  absent. 
  There 
  is 
  every 
  reason 
  to 
  assume 
  that 
  bush-buck 
  

   would 
  do 
  the 
  same, 
  in 
  the 
  absence 
  of 
  leopard 
  and 
  of 
  human 
  hunters. 
  

  

  The 
  correlation 
  is 
  perfect 
  at 
  every 
  point, 
  and 
  it 
  is 
  an 
  entirely 
  reasonable 
  conclusion 
  

   that 
  in 
  the 
  absence 
  of 
  leopard 
  inland 
  range 
  of 
  fly 
  would 
  on 
  the 
  average 
  be 
  as 
  extensive 
  

   along 
  well 
  protected 
  portions 
  of 
  the 
  riparian 
  belt 
  as 
  on 
  the 
  islands 
  where 
  situtunga 
  

   has 
  increased 
  or 
  as 
  at 
  the 
  few 
  points 
  along 
  the 
  mainland 
  shore 
  where 
  the 
  bush-buck 
  

   has 
  found 
  exceptionally 
  secure 
  protection. 
  

  

  There 
  would 
  be 
  inland 
  extension 
  of 
  infestation 
  to 
  approximately 
  5 
  times 
  its 
  present 
  

   depth 
  at 
  many 
  points, 
  and 
  along 
  extensive 
  reaches 
  of 
  mainland 
  shore, 
  if 
  it 
  were 
  not 
  

  

  