﻿412 
  W. 
  F. 
  FISKE. 
  

  

  VII 
  (a). 
  Breeding 
  Grounds 
  on 
  Sand 
  and 
  Gravel 
  Beaches. 
  

  

  The 
  larva 
  of 
  Glossina 
  palpalis 
  is 
  nourished 
  by 
  the 
  female 
  until 
  full-fed 
  and 
  ready 
  

   to 
  pupate, 
  and 
  is 
  then 
  carried 
  by 
  her 
  and 
  deposited 
  in 
  protected 
  situations 
  known 
  

   as 
  breeding 
  places. 
  The 
  most 
  attractive 
  breeding 
  grounds 
  are 
  the 
  deposits 
  of 
  clean 
  

   dry 
  beach 
  sand 
  or 
  gravel 
  that 
  occur 
  more 
  or 
  less 
  frequently 
  along 
  the 
  shore. 
  They 
  

   must 
  be 
  in 
  or 
  near 
  to 
  the 
  course 
  followed 
  by 
  the 
  streams 
  of 
  moving 
  flies, 
  i.e., 
  very 
  

   few 
  puparia 
  can 
  be 
  found 
  in 
  situations 
  much 
  off 
  the 
  course 
  of 
  fly 
  traffic 
  — 
  and 
  they 
  

   must 
  be 
  shaded. 
  

  

  Shade 
  may 
  be 
  afforded 
  by 
  almost 
  anything, 
  provided 
  only 
  that 
  it 
  is 
  not 
  more 
  

   than 
  two 
  or 
  three 
  feet 
  above 
  the 
  surface 
  of 
  the 
  soil. 
  If 
  much 
  higher 
  the 
  spot 
  will 
  

   be 
  avoided. 
  Vegetation, 
  both 
  shrubby 
  and 
  herbaceous, 
  rocks, 
  logs, 
  stumps, 
  etc., 
  

   will 
  provide 
  attractive 
  shelter 
  from 
  the 
  sun. 
  The 
  need 
  of 
  it 
  is 
  imperative, 
  for 
  the 
  

   larvae 
  never 
  penetrate 
  more 
  than 
  two 
  or 
  three 
  inches 
  below 
  the 
  surface, 
  and 
  the 
  sun 
  

   striking 
  full 
  on 
  the 
  surface 
  will 
  kill 
  the 
  puparia 
  quickly. 
  Even 
  in 
  the 
  shaded, 
  sand- 
  

   strewn 
  caves 
  which 
  occur 
  along 
  the 
  shores 
  of 
  certain 
  islands, 
  into 
  which 
  the 
  sun 
  

   never 
  penetrates, 
  and 
  which 
  are 
  sometimes 
  attractive 
  as 
  breeding 
  places, 
  the 
  flies 
  

   will 
  only 
  deposit 
  their 
  larvae 
  around 
  the 
  edges, 
  close 
  under 
  the 
  overhanging 
  rock, 
  

   as 
  though 
  fearful 
  lest 
  the 
  rock 
  farther 
  above 
  the 
  surface 
  of 
  the 
  soil 
  might 
  not 
  

   provide 
  the 
  continuous 
  shelter 
  required. 
  , 
  

  

  In 
  especially 
  attractive 
  spots 
  — 
  if 
  there 
  are 
  not 
  too 
  many 
  of 
  them 
  — 
  large 
  deposits 
  

   of 
  puparia 
  and 
  puparium 
  shells 
  may 
  frequently 
  be 
  found. 
  The 
  record 
  " 
  catch 
  ' 
  : 
  

   which 
  was 
  accurately 
  counted 
  was 
  made 
  in 
  September 
  1914 
  on 
  the 
  island 
  of 
  Zinga, 
  

   beneath 
  an 
  old 
  stump 
  thrown 
  upon 
  the 
  beach 
  by 
  some 
  storm, 
  and 
  overgrown 
  with 
  

   " 
  morning 
  glory 
  " 
  vines. 
  It 
  required 
  one 
  boy 
  35 
  minutes 
  to 
  sift 
  the 
  soil 
  beneath 
  this 
  

   bit 
  of 
  shelter. 
  In 
  a 
  space 
  hardly 
  more 
  than 
  a 
  yard 
  square 
  he 
  found 
  : 
  

  

  Empty 
  shells 
  . 
  . 
  . 
  . 
  478 
  Kate 
  per 
  boy 
  hour 
  814 
  

  

  Healthy 
  puparia 
  . 
  . 
  . 
  . 
  144 
  „ 
  „ 
  247 
  

  

  Total 
  622 
  „ 
  „ 
  1061 
  

  

  Relatively 
  few 
  accurate 
  counts 
  of 
  puparia 
  and 
  pupal 
  shells 
  were 
  attempted, 
  

   lor 
  unless 
  inordinate 
  pains 
  are 
  taken, 
  the 
  figures 
  mean 
  little 
  or 
  nothing. 
  There 
  

   may 
  be 
  much 
  or 
  little 
  attractive 
  breeding 
  ground, 
  and 
  if 
  much 
  of 
  it, 
  puparia 
  are 
  

   difficult 
  to 
  find 
  — 
  if 
  little 
  of 
  it, 
  they 
  are 
  more 
  easy 
  to 
  find. 
  The 
  number 
  of 
  puparia 
  

   found 
  at 
  different 
  seasons 
  of 
  the 
  year 
  means 
  nothing, 
  for 
  the 
  upspringing 
  or 
  withering 
  

   of 
  vegetation 
  affects 
  the 
  extent 
  and 
  attractiveness 
  of 
  breeding 
  ground 
  profoundly 
  ; 
  

   and 
  the 
  same 
  is 
  true 
  of 
  the 
  more 
  or 
  less 
  regular 
  fluctuations 
  in 
  level 
  of 
  the 
  lake. 
  

   The 
  accompanying 
  table 
  (Table 
  XXVI) 
  will 
  indicate 
  the 
  numbers 
  likely 
  to 
  be 
  found 
  

   by 
  expert 
  fly 
  boys 
  under 
  favourable 
  conditions 
  — 
  as 
  along 
  the 
  " 
  fly 
  beaches 
  " 
  (each 
  

   locality 
  except 
  that 
  on 
  Tavu 
  Island 
  was 
  a 
  " 
  fly 
  beach 
  "). 
  

  

  For 
  a 
  time 
  it 
  was 
  thought 
  that 
  data 
  on 
  the 
  proportionate 
  numbers 
  of 
  pupae 
  in 
  

   different 
  stages 
  of 
  their 
  development 
  might 
  be 
  worth 
  collecting, 
  but 
  after 
  a 
  time 
  

   the 
  idea 
  was 
  discarded. 
  The 
  healthy 
  puparia 
  were 
  opened, 
  and 
  those 
  showing 
  

   the 
  grey 
  colour 
  of 
  the 
  adult 
  were 
  classed 
  as 
  " 
  late 
  stages," 
  while 
  those 
  showing 
  

   no 
  colour 
  except 
  on 
  the 
  eyes 
  were 
  classed 
  as 
  " 
  early 
  stages." 
  The 
  data 
  of 
  this 
  

  

  