﻿16 
  \V. 
  A. 
  LAMBORN. 
  

  

  custom 
  of 
  that 
  people, 
  with 
  decomposed 
  human 
  excreta. 
  A 
  hut 
  with 
  a 
  plank 
  

   flooring, 
  built 
  over 
  the 
  water 
  on 
  piles, 
  accommodated 
  a 
  herd 
  of 
  goats, 
  about 
  40, 
  

   at 
  night 
  and 
  during 
  a 
  part 
  of 
  the 
  day, 
  their 
  dejecta 
  dropping 
  into 
  the 
  water 
  ; 
  and 
  

   three 
  little 
  shacks, 
  also 
  overhanging 
  the 
  water, 
  provided 
  cover 
  for 
  inhabitants 
  

   proposing 
  to 
  indulge 
  in 
  the 
  luxury 
  of 
  a 
  bath. 
  The 
  vegetable 
  pollution 
  of 
  this 
  water 
  

   must 
  necessarily 
  have 
  been 
  considerable 
  owing 
  to 
  the 
  method 
  of 
  fish 
  cultivation 
  

   adopted 
  by 
  the 
  Chinese. 
  A 
  large 
  amount 
  of 
  freshly 
  chopped 
  succulent 
  grass 
  is 
  

   from 
  time 
  to 
  time 
  put 
  into 
  the 
  water 
  for 
  the 
  purpose 
  of 
  " 
  fattening 
  the 
  fish," 
  according 
  

   to 
  one 
  of 
  that 
  people. 
  The 
  excreta 
  of 
  goats 
  were 
  said 
  to 
  serve 
  the 
  same 
  purpose, 
  

   for 
  which 
  in 
  China, 
  but 
  not 
  in 
  the 
  Malay 
  States, 
  bones 
  also 
  are 
  put 
  into 
  the 
  water. 
  

   When 
  there 
  is 
  thunder 
  in 
  the 
  air 
  it 
  is 
  the 
  further 
  practice 
  to 
  put 
  in 
  also 
  chopped 
  

   banana 
  leaves 
  by 
  way 
  of 
  " 
  medicine 
  " 
  for 
  the 
  fish, 
  which 
  are 
  said 
  to 
  be 
  then 
  liable 
  to 
  

   sickness. 
  

  

  The 
  fish 
  may 
  perhaps 
  feed 
  up 
  on 
  these 
  vegetable 
  matters 
  — 
  one 
  is 
  hardly 
  in 
  a 
  

   position 
  to 
  express 
  an 
  opinion 
  ; 
  but 
  it 
  would 
  seem 
  more 
  than 
  probable 
  that 
  they 
  

   feed 
  on 
  the 
  organisms, 
  among 
  which 
  a 
  species 
  of 
  Euglena 
  was 
  dominant, 
  that 
  on 
  this 
  

   and 
  similar 
  ponds 
  formed 
  an 
  extremely 
  dense 
  semi-solid 
  scum 
  on 
  the 
  surface. 
  The 
  

   water, 
  even 
  when 
  taken 
  from 
  below 
  the 
  surface, 
  was 
  green 
  by 
  reason 
  of 
  its 
  high 
  algal 
  

   content 
  and 
  was 
  often 
  malodorous. 
  

  

  The 
  additional 
  use 
  of 
  these 
  ponds 
  for 
  the 
  cultivation 
  of 
  " 
  cabbage 
  weed 
  " 
  and 
  

   other 
  floating 
  plants, 
  which 
  must 
  depend 
  on 
  a 
  large 
  organic 
  content 
  in 
  the 
  water, 
  

   has 
  already 
  been 
  noted. 
  

  

  With 
  regard 
  to 
  the 
  other 
  group 
  of 
  breeding-places, 
  it 
  would 
  seem 
  significant 
  

   that 
  those 
  providing 
  the 
  larvae 
  of 
  A. 
  aconitus 
  were 
  entirely 
  remote 
  from 
  houses 
  and 
  

   were 
  free 
  from 
  large 
  aquatic 
  plants, 
  and 
  that 
  two 
  of 
  those 
  in 
  which 
  these 
  larvae 
  

   were 
  absent 
  were 
  in 
  the 
  neighbourhood 
  of 
  a 
  Chinese 
  farm. 
  They 
  were 
  largely 
  

   covered 
  with 
  floating 
  weed, 
  the 
  growth 
  of 
  which 
  may 
  or 
  may 
  not 
  have 
  been 
  encouraged 
  

   in 
  the 
  usual 
  way 
  by 
  the 
  farmer, 
  who 
  kept 
  pigs. 
  These 
  two 
  ponds 
  were 
  from 
  time 
  

   to 
  time 
  used 
  as 
  wallows 
  by 
  buffalos, 
  which, 
  as 
  is 
  usual 
  with 
  Herbivora, 
  would 
  foul 
  

   them 
  on 
  leaving. 
  

  

  The 
  supposition 
  is, 
  therefore, 
  that 
  some 
  quality 
  of 
  the 
  water 
  strongly 
  affects 
  

   the 
  distribution 
  of 
  A. 
  aconitus, 
  either 
  directly 
  or 
  indirectly, 
  by 
  influencing 
  the 
  character 
  

   of 
  the 
  food, 
  and 
  it 
  was 
  hoped 
  to 
  determine 
  the 
  nature 
  of 
  this 
  quality 
  by 
  water 
  

   analysis. 
  Various 
  samples 
  of 
  water 
  from 
  these 
  breeding-places 
  were 
  submitted 
  

   to 
  Mr. 
  R. 
  W. 
  Blair, 
  the 
  Government 
  chemist, 
  who, 
  though 
  over-pressed 
  with 
  routine 
  

   and 
  other 
  laboratory 
  work, 
  was 
  so 
  kind 
  as 
  to 
  make 
  time 
  to 
  carry 
  out 
  some 
  preliminary 
  

   analyses 
  (see 
  Table 
  IV., 
  p. 
  17). 
  But 
  at 
  this 
  important 
  stage 
  of 
  the 
  investigation 
  

   the 
  writer 
  was 
  obliged 
  to 
  go 
  on 
  leave 
  and 
  so 
  no 
  final 
  conclusions 
  were 
  arrived 
  at. 
  

  

  The 
  results 
  of 
  the 
  following 
  technique 
  as 
  to 
  A 
  . 
  umbrosus 
  serve 
  to 
  show 
  how 
  larval 
  

   distribution 
  may 
  be 
  influenced 
  by 
  making 
  an 
  alteration 
  in 
  environment. 
  A 
  large 
  

   pool, 
  about 
  6 
  feet 
  broad, 
  15 
  feet 
  long 
  and 
  1 
  to 
  \\ 
  feet 
  in 
  depth, 
  situated 
  near 
  Kuala 
  

   Lampur 
  in 
  secondary 
  bush, 
  by 
  which 
  it 
  was 
  largely, 
  though 
  not 
  entirely 
  shaded 
  , 
  

   from 
  the 
  overhead 
  sun, 
  had 
  consistently 
  afforded 
  in 
  fairty 
  large 
  numbers 
  and 
  in 
  pure 
  

   culture 
  the 
  larvae 
  of 
  A. 
  umbrosus, 
  a 
  jungle 
  breeder, 
  at 
  all 
  events 
  when 
  away 
  from 
  the 
  

   coast. 
  The 
  disappearance 
  of 
  the 
  bush 
  species, 
  A. 
  aitkeni 
  and 
  A. 
  leucosphyrus, 
  and 
  

   their 
  replacement 
  by 
  open 
  country 
  species 
  on 
  clearing, 
  was 
  recognised 
  years 
  ago 
  

   by 
  Dr. 
  Fletcher 
  and 
  Mr. 
  Pratt. 
  The 
  success 
  which 
  has 
  attended 
  Dr. 
  Watson's 
  

   attempt 
  at 
  Port 
  Swettenham 
  and 
  Klang 
  to 
  eradicate 
  .-1. 
  umbrosus 
  by 
  clearing 
  the 
  

   bush 
  and 
  by 
  draining 
  has, 
  of 
  course, 
  long 
  since 
  been 
  appreciated 
  ; 
  and 
  Dr. 
  Hacker 
  

   has 
  recorded 
  an 
  instance 
  of 
  the 
  replacement 
  of 
  this 
  species 
  by 
  A. 
  barbirostris 
  after 
  

   clearing 
  was 
  effected.* 
  For 
  the 
  sake 
  of 
  obtaining 
  concrete 
  data 
  as 
  to 
  the 
  effect 
  of 
  

  

  * 
  F.M.S. 
  Malaria 
  Bureau 
  Reports, 
  i, 
  p. 
  53. 
  

  

  