﻿INVESTIGATIONS 
  INTO 
  THE 
  BIONOMICS 
  OF 
  GLOSSINA 
  PALPALIS. 
  

  

  403 
  

  

  The 
  second 
  notable 
  feature 
  of 
  the 
  experiment 
  was 
  the 
  behaviour 
  of 
  fly 
  toward 
  

   the 
  bulls 
  at 
  different 
  hours 
  of 
  the 
  day. 
  The 
  experiment 
  extended 
  over 
  three 
  days. 
  

   Each 
  day 
  the 
  morning 
  was 
  dull 
  and 
  rainy 
  and 
  each 
  day 
  the 
  animals 
  were 
  taken 
  

   to 
  the 
  shore 
  as 
  soon 
  as 
  the 
  clouds 
  broke 
  and 
  while 
  the 
  vegetation 
  was 
  still 
  wet. 
  

   As 
  will 
  be 
  seen 
  by 
  Table 
  XXV 
  the 
  bulls 
  were 
  fed 
  upon 
  much 
  more 
  frequently 
  during 
  

   the 
  first 
  hours 
  following 
  the 
  clearing, 
  but 
  the 
  Varanus 
  was 
  somewhat 
  more 
  freely 
  

   attacked 
  later 
  on. 
  

  

  Table 
  XXV. 
  

  

  Behaviour 
  of 
  Glossina 
  towards 
  Domestic 
  Ox 
  as 
  affected 
  by 
  Presence 
  of 
  Tabanus. 
  

  

  Animals. 
  

  

  Bites 
  per 
  hour 
  inflicted 
  

  

  during 
  first 
  hours 
  following 
  

  

  clearing 
  of 
  weather; 
  

  

  Tabanus 
  not 
  active 
  

  

  Bites 
  per 
  hour 
  inflicted 
  

  

  during 
  later 
  hours 
  ; 
  

  

  Tabanus 
  active. 
  

  

  Ankole 
  Bull 
  

   Indian 
  ,, 
  

   Half 
  breed 
  „ 
  

   Varanus 
  

  

  7-3 
  

  

  •3 
  

  

  50 
  

  

  5-0 
  

  

  1-1 
  

  

  •o 
  

  

  •7 
  

  

  7'4 
  

  

  The 
  fact 
  that 
  the 
  number 
  of 
  flies 
  feeding 
  on 
  Varanus 
  increased 
  after 
  the 
  firs^ 
  

   hour, 
  instead 
  of 
  falling 
  off 
  sharply, 
  proved 
  conclusively 
  that 
  the 
  flies 
  were 
  no 
  less 
  

   active 
  or 
  less 
  willing 
  to 
  feed, 
  and 
  the 
  explanation 
  for 
  the 
  sharp 
  decline 
  in 
  number 
  

   of 
  bites 
  inflicted 
  on 
  the 
  bulls 
  is 
  unquestionably 
  due 
  to 
  the 
  fact 
  that 
  an 
  hour 
  or 
  so 
  

   after 
  the 
  clouds 
  broke 
  and 
  when 
  the 
  vegetation 
  was 
  quite 
  dry 
  a 
  large 
  species 
  of 
  

   Tabanus 
  appeared 
  and 
  caused 
  the 
  animals 
  much 
  annoyance. 
  Not 
  even 
  the 
  phleg- 
  

   matic 
  Ankole 
  would 
  permit 
  these 
  great 
  flies 
  to 
  approach 
  it 
  ; 
  the 
  Glossina 
  were 
  

   incidently 
  included 
  in 
  the 
  interdiction, 
  and 
  were 
  effectually 
  prevented 
  from 
  attacking 
  

   if 
  there 
  was 
  any 
  Tabanus 
  about. 
  But 
  no 
  Tabanus 
  or 
  any 
  other 
  flies 
  than 
  Glossina 
  

   attacked 
  the 
  Varanus. 
  

  

  These 
  experiments 
  were 
  inconclusive 
  in 
  so 
  far 
  as 
  proving 
  the 
  relative 
  status 
  of 
  

   the 
  domestic 
  ox 
  as 
  a 
  host 
  of 
  Glossina 
  palpalis 
  ; 
  but 
  they 
  conclusively 
  showed 
  

   that 
  where 
  such 
  animals 
  are 
  concerned 
  freedom 
  of 
  attack 
  by 
  Glossina 
  is 
  to 
  a 
  

   very 
  large 
  extent 
  determined 
  by 
  the 
  temperament 
  of 
  the 
  individual, 
  and 
  also 
  by 
  

   extraneous 
  circumstances 
  and 
  conditions 
  of 
  time 
  and 
  place. 
  

  

  The 
  experiments 
  were 
  continued 
  over 
  several 
  days, 
  more 
  in 
  an 
  effort 
  to 
  find 
  

   some 
  locality 
  where 
  there 
  was 
  tsetse 
  but 
  no 
  Tabanus, 
  and 
  also 
  in 
  an 
  effort 
  to 
  induce 
  

   a 
  " 
  following 
  swarm 
  " 
  to 
  collect 
  on 
  either 
  an 
  ox 
  or 
  Varanus, 
  but 
  without 
  result. 
  

   The 
  cattle 
  found 
  the 
  Tabanus 
  so 
  annoying 
  that 
  it 
  was 
  necessary 
  to 
  constrain 
  them 
  to 
  

   remain 
  near 
  the 
  Lake 
  shore 
  at 
  hours 
  when 
  these 
  flies 
  were 
  active, 
  and 
  they 
  were 
  

   generally 
  distributed 
  at 
  all 
  points 
  along 
  this 
  reach 
  of 
  shore. 
  The 
  Varanus, 
  also 
  

   proved 
  intractable, 
  and 
  would 
  not 
  remain 
  quiet 
  in 
  restraint. 
  On 
  this 
  account, 
  

   it 
  is 
  believed, 
  the 
  " 
  following 
  swarm 
  " 
  (vide 
  Sect. 
  IV) 
  refused 
  to 
  collect. 
  

  

  