﻿49 
  

  

  FURTHER 
  NOTES 
  ON 
  THE 
  BIONOMICS 
  OF 
  GLOSSINA 
  MORSITANS 
  

   IN 
  NORTHERN 
  RHODESIA. 
  

   By 
  Ll. 
  Lloyd, 
  

   Entomologist 
  to 
  the 
  British 
  South 
  Africa 
  Company 
  in 
  Northern 
  Rhodesia. 
  

   (Plates 
  X-XIII, 
  and 
  Map.) 
  

   Since 
  the 
  cessation 
  of 
  the 
  work 
  of 
  the 
  Luangwa 
  Sleeping 
  Sickness 
  Commission 
  in 
  

   Northern 
  Rhodesia 
  the 
  investigation 
  into 
  the 
  bionomics 
  of 
  Glossina 
  morsitans 
  has 
  been 
  

   carried 
  on 
  at 
  Ngoa, 
  in 
  the 
  Mpika 
  Division, 
  on 
  the 
  high 
  ground 
  of 
  the 
  Congo-Zambezi 
  

   watershed. 
  The 
  work 
  included 
  a 
  study 
  of 
  the 
  influence 
  of 
  various 
  bloods 
  on 
  the 
  

   breeding 
  capabilities 
  of 
  the 
  fly 
  and 
  further 
  investigation 
  of 
  the 
  breeding 
  habits 
  and 
  

   haunts 
  of 
  the 
  insect 
  in 
  nature. 
  The 
  following 
  notes 
  embody 
  the 
  results 
  of 
  the 
  work 
  

   during 
  the 
  eight 
  months 
  from 
  January 
  to 
  August, 
  1913. 
  The 
  climatic 
  conditions 
  

   during 
  this 
  period 
  are 
  given 
  in 
  Table 
  1, 
  the 
  temperatures 
  being 
  those 
  of 
  the 
  laboratory. 
  

  

  Table 
  1. 
  

   Showing 
  the 
  Temperature 
  and 
  Rainfall 
  at 
  Ngoa, 
  1913. 
  

  

  Laboratory 
  Temperatures. 
  

  

  

  

  

  

  

  Rainfall. 
  

  

  Av. 
  Max. 
  

  

  Av. 
  Min. 
  

  

  Mean. 
  

  

  January 
  . 
  . 
  

  

  

  

  

  3-85 
  in. 
  

  

  (15th-31st) 
  

  

  

  

  

  

  February 
  

  

  72-7° 
  F. 
  

  

  64-8° 
  F. 
  

  

  68-7° 
  F. 
  

  

  5-86 
  

  

  March 
  

  

  71 
  1° 
  

  

  64-2° 
  

  

  67-6° 
  

  

  10-40 
  

  

  April 
  

  

  73-6° 
  

  

  64-2° 
  

  

  68-9° 
  

  

  0-77 
  

  

  May 
  

  

  71-2° 
  

  

  59-2° 
  

  

  65-2° 
  

  

  0-82 
  

  

  June 
  

  

  65-7° 
  

  

  50-1° 
  

  

  57.9° 
  

  

  0-00 
  

  

  July 
  

  

  64-4° 
  

  

  51-8° 
  

  

  58-1° 
  

  

  0-00 
  

  

  August 
  

  

  70-2° 
  

  

  58-0° 
  

  

  641° 
  

  

  o-oo 
  

  

  Influence 
  of 
  Various 
  Bloods 
  on 
  Breeding 
  Capabilities. 
  

  

  In 
  the 
  method 
  which 
  was 
  adopted, 
  a 
  definite 
  number 
  of 
  freshly 
  caught 
  female 
  flies 
  

   were 
  fed 
  on 
  goats, 
  monkeys, 
  fowls, 
  ducks 
  and 
  chameleons. 
  In 
  most 
  of 
  the 
  experi- 
  

   ments 
  the 
  flies 
  were 
  kept 
  in 
  the 
  usual 
  type 
  of 
  fly 
  bottle, 
  four 
  females 
  and 
  two 
  males 
  

   in 
  each. 
  A 
  few 
  of 
  the 
  series 
  were 
  kept 
  in 
  large 
  wooden 
  cages 
  with 
  fronts 
  of 
  mosquito 
  

   muslin. 
  Records 
  were 
  taken 
  of 
  the 
  length 
  of 
  life 
  of 
  each 
  fly 
  in 
  captivity 
  and 
  the 
  

   numbers 
  of 
  pupae 
  and 
  aborted 
  larvae 
  which 
  were 
  deposited 
  ; 
  each 
  pupa 
  was 
  also 
  

   measured. 
  Nineteen 
  experiments 
  were 
  commenced, 
  of 
  which 
  thirteen 
  were 
  com- 
  

   pleted. 
  The 
  original 
  intention 
  was 
  to 
  breed 
  the 
  flies 
  through 
  more 
  than 
  one 
  

   generation 
  on 
  the 
  various 
  bloods, 
  but 
  owing 
  to 
  removal 
  to 
  another 
  part 
  of 
  the 
  

   country, 
  this 
  was 
  possible 
  only 
  to 
  a 
  very 
  small 
  extent. 
  

  

  Pupae 
  were 
  produced 
  in 
  small 
  numbers, 
  especially 
  from 
  June 
  to 
  August, 
  which 
  are 
  

   the 
  coldest 
  months 
  of 
  the 
  year, 
  when 
  some 
  of 
  the 
  series 
  did 
  not 
  produce 
  a 
  single 
  pupa. 
  

   The 
  doors 
  and 
  windows 
  of 
  the 
  laboratory 
  were 
  made 
  of 
  loose 
  reeds, 
  so 
  that 
  the 
  flies 
  

   were 
  exposed 
  to 
  the 
  full 
  cold 
  at 
  night 
  and 
  obtained 
  no 
  direct 
  benefit 
  from 
  the 
  sun 
  

   in 
  the 
  daytime, 
  as 
  do 
  the 
  flies 
  in 
  nature. 
  Pupae 
  were 
  being 
  found 
  in 
  the 
  bush 
  in 
  con- 
  

   siderable 
  numbers 
  during 
  July 
  and 
  August, 
  while 
  during 
  the 
  rains 
  breeding 
  was 
  not 
  

   active. 
  The 
  artificial 
  conditions 
  in 
  the 
  laboratory 
  thus 
  tended 
  to 
  reverse 
  what 
  takes 
  

   place 
  in 
  nature. 
  The 
  influence 
  of 
  the 
  low 
  temperatures 
  is 
  shown 
  in 
  Table 
  II, 
  in 
  which 
  

  

  C10 
  B 
  

  

  