﻿444 
  G. 
  D. 
  HALE 
  CARPENTER. 
  

  

  towards 
  the 
  direction 
  whence 
  rain 
  might 
  enter, 
  and 
  also 
  so 
  that 
  as, 
  little 
  sun 
  as 
  

   possible 
  entered 
  under 
  the 
  roof. 
  Advantage 
  was 
  taken 
  where 
  possible 
  of 
  natural 
  

   protection 
  afforded 
  by 
  trees 
  and 
  bushes. 
  The 
  soil 
  was 
  either 
  red 
  or 
  white 
  coarse 
  

   sand 
  mixed 
  with 
  small 
  stones. 
  

  

  Arrangements 
  were 
  made 
  for 
  a 
  reliable 
  native 
  to 
  visit 
  each 
  island 
  at 
  regular 
  

   intervals 
  of 
  ten 
  days, 
  but 
  on 
  a 
  few 
  occasions 
  the 
  interval 
  was 
  unavoidably 
  much 
  

   longer. 
  I 
  think 
  that 
  ten 
  days, 
  or 
  perhaps 
  a 
  fortnight, 
  is 
  the 
  longest 
  interval 
  that 
  

   should 
  elapse 
  ; 
  during 
  three 
  weeks 
  there 
  is 
  time 
  for 
  pupae 
  to 
  hatch 
  out. 
  

  

  I 
  went 
  to 
  the 
  islands 
  on 
  5th 
  and 
  6th 
  January 
  1922, 
  and 
  satisfied 
  myself 
  by 
  

   watching 
  the 
  boy 
  actually 
  collecting 
  that 
  he 
  did 
  truly 
  find 
  the 
  pupae 
  in 
  the 
  shelters. 
  

   As 
  a 
  matter 
  of 
  fact 
  there 
  was 
  no 
  other 
  place 
  on 
  any 
  of 
  the 
  neighbouring 
  islands 
  

   where 
  he 
  could 
  have 
  procured 
  the 
  same 
  number 
  of 
  pupae 
  in 
  the 
  time 
  given 
  him. 
  

   A 
  bonus 
  was 
  given 
  of 
  20 
  cents, 
  per 
  hundred 
  pupae 
  in 
  order 
  to 
  ensure 
  a 
  thorough 
  

   search 
  of 
  the 
  shelters. 
  

  

  Certain 
  of 
  the 
  shelters 
  proved 
  to 
  be 
  much 
  more 
  attractive 
  than 
  others. 
  On 
  

   Bulago, 
  Nos. 
  1, 
  5, 
  6, 
  8, 
  and 
  especially 
  5 
  and 
  6, 
  were 
  most 
  attractive, 
  and 
  on 
  Kimmi 
  

   Nos. 
  2, 
  5 
  and 
  6, 
  and 
  especially 
  2, 
  provided 
  most 
  pupae. 
  

  

  It 
  is 
  noteworthy 
  that 
  the 
  natural 
  breeding-places 
  that 
  were 
  especially 
  selected 
  

   for 
  comparison 
  with 
  the 
  artificial 
  breeding-places, 
  as 
  likely 
  to 
  provide 
  most 
  pupae, 
  

   proved 
  very 
  inferior 
  to 
  the 
  shelters 
  (B.2, 
  K.4 
  and 
  7). 
  The 
  largest 
  number 
  of 
  pupae 
  

   collected 
  at 
  any 
  visit 
  from 
  one 
  of 
  the 
  natural 
  breeding-places 
  was 
  116, 
  whereas 
  the 
  

   largest 
  number 
  from 
  a 
  shelter 
  was 
  551. 
  On 
  the 
  other 
  hand 
  some 
  of 
  the 
  shelters 
  (B.3) 
  

   were 
  inferior 
  to 
  some 
  of 
  the 
  natural 
  places 
  (see 
  Table). 
  

  

  The 
  number 
  of 
  pupae 
  yielded 
  bv 
  any 
  one 
  shelter 
  showed 
  great 
  variation 
  : 
  thus 
  

   No. 
  5 
  on 
  Bulago 
  yielded 
  on 
  7th 
  September, 
  126 
  ; 
  on 
  the 
  18th, 
  100 
  ; 
  on 
  the 
  26th, 
  33 
  ; 
  

   on 
  7th 
  October, 
  256. 
  Again, 
  No. 
  2 
  on 
  Kimmi 
  yielded 
  423 
  on 
  25th 
  November 
  ; 
  4 
  on 
  

   6th 
  December 
  ; 
  75 
  on 
  16th 
  December. 
  It 
  is 
  difficult 
  to 
  account 
  for 
  these 
  sudden 
  

   drops, 
  but 
  a 
  possible 
  explanation 
  may 
  be 
  that 
  for 
  a 
  short 
  period 
  there 
  was 
  an 
  absence 
  

   of 
  a 
  good 
  supply 
  of 
  food 
  in 
  the 
  neighbourhood 
  of 
  that 
  particular 
  shelter. 
  

  

  General 
  Conclusions. 
  

  

  A 
  great 
  amount 
  of 
  labour 
  has 
  been 
  spent 
  in 
  plotting 
  out 
  the 
  results 
  together 
  

   with 
  records 
  of 
  temperature, 
  rainfall, 
  hours 
  of 
  sunshine 
  and 
  relative 
  humidity, 
  

   calculated 
  from 
  meteorological 
  records 
  kept 
  at 
  Entebbe. 
  Unfortunately 
  it 
  was 
  not 
  

   possible 
  to 
  obtain 
  meteorological 
  records 
  for 
  the 
  islands 
  on 
  which 
  the 
  experiment 
  

   was 
  being 
  made, 
  but 
  they 
  are 
  sufficiently 
  close 
  to 
  Entebbe 
  for 
  the 
  data 
  obtained 
  

   to 
  be 
  useful. 
  

  

  The 
  total 
  yield 
  for 
  each 
  period 
  was 
  divided 
  by 
  the 
  number 
  of 
  days 
  to 
  get 
  a 
  daily 
  

   average 
  for 
  the 
  period, 
  and 
  daily 
  averages 
  of 
  the 
  meteorological 
  data 
  were 
  obtained 
  

   for 
  comparison. 
  

  

  Study 
  of 
  the 
  charts 
  (not 
  reproduced) 
  shows 
  no 
  definite 
  correlation 
  between 
  the 
  

   pupae 
  curve 
  and 
  any 
  of 
  the 
  others 
  ; 
  although 
  I 
  had 
  expected 
  to 
  find 
  that 
  the 
  seasons 
  

   of 
  least 
  humidity 
  would 
  be 
  the 
  seasons 
  when 
  most 
  pupae 
  were 
  deposited. 
  

  

  Finally, 
  I 
  must 
  reluctantly 
  conclude 
  that 
  my 
  hopes 
  of 
  the 
  utility 
  of 
  this 
  method 
  

   as 
  a 
  means 
  of 
  destroying 
  Glossina 
  palpalis 
  without 
  any 
  other 
  measures 
  at 
  all, 
  have 
  

   not 
  been 
  justified. 
  After 
  very 
  nearly 
  a 
  year 
  there 
  was 
  no 
  appreciable 
  diminution 
  

   in 
  the 
  number 
  of 
  pupae 
  deposited. 
  

  

  The 
  method, 
  however, 
  has 
  proved 
  its 
  value 
  as 
  a 
  means 
  of 
  readily 
  obtaining 
  large 
  

   numbers 
  of 
  pupae 
  for 
  laboratory 
  purposes. 
  A 
  batch 
  was 
  sent 
  to 
  the 
  Zoological 
  

   Society, 
  and 
  many 
  arrived 
  alive. 
  Unfortunately 
  a 
  breakdown 
  in 
  the 
  heating 
  arrange- 
  

   ments 
  of 
  the 
  insect 
  house 
  on 
  two 
  very 
  cold 
  nights 
  resulted 
  in 
  the 
  death 
  of 
  those 
  that 
  

   had 
  survived 
  the 
  voyage. 
  

  

  It 
  seems 
  probable 
  that 
  combined 
  with 
  destruction 
  of 
  the 
  most 
  favoured 
  breeding- 
  

   places 
  this 
  method 
  might 
  greatly 
  help 
  in 
  reducing 
  the 
  numbers 
  of 
  the 
  fly. 
  

  

  