﻿THE 
  DEVELOPMENT 
  OF 
  FLAGELLATED 
  ORGANISMS. 
  371 
  

  

  in 
  figs. 
  8 
  to 
  12 
  of 
  Hue 
  XI 
  of 
  the 
  plate, 
  were 
  suddenly 
  en- 
  

   countered, 
  together 
  with 
  the 
  intermediate 
  forms 
  shown 
  in 
  

   the 
  first 
  seven 
  figures 
  of 
  the 
  same 
  line. 
  Since 
  that 
  time 
  a 
  

   number 
  of 
  cultures 
  have 
  been 
  made 
  and 
  further 
  intermediate 
  

   forms 
  have 
  been 
  met 
  with, 
  but 
  in 
  these 
  it 
  has 
  taken 
  three 
  or 
  

   four 
  days 
  before 
  large 
  flagellated 
  forms 
  were 
  found, 
  and 
  the 
  

   fully 
  elongated 
  trypanosonia-like 
  forms 
  of 
  case 
  37 
  have 
  not 
  

   again 
  been 
  seen 
  so 
  perfectly. 
  What 
  the 
  conditions 
  were 
  

   which 
  favoured 
  the 
  full 
  development 
  in 
  so 
  short 
  a 
  time 
  in 
  

   that 
  case 
  I 
  cannot 
  say. 
  The 
  case 
  was 
  a 
  more 
  acute 
  one 
  than 
  

   is 
  often 
  seen 
  in 
  Calcutta, 
  but 
  a 
  second 
  lot 
  of 
  spleen 
  blood 
  

   obtained 
  a 
  few 
  days 
  later 
  failed 
  to 
  develop 
  in 
  the 
  same 
  way, 
  

   so 
  there 
  must 
  have 
  been 
  some 
  other 
  factor 
  present. 
  As 
  in 
  

   all 
  my 
  other 
  successful 
  cultures 
  the 
  steady 
  development 
  of 
  

   the 
  parasites 
  day 
  by 
  day 
  could 
  readily 
  be 
  traced, 
  it 
  will 
  be 
  

   best 
  to 
  describe 
  these 
  changes 
  in 
  the 
  order 
  of 
  their 
  develop- 
  

   ment. 
  For 
  the 
  purpose 
  of 
  illustrating 
  the 
  progress 
  of 
  the 
  

   evolution 
  the 
  forms 
  seen 
  each 
  day 
  in 
  two 
  cases 
  have 
  been 
  

   drawn 
  in 
  the 
  plate, 
  each 
  line 
  representing 
  one 
  day's 
  appear- 
  

   ances. 
  

  

  Stage 
  of 
  Development 
  after 
  Twenty-four 
  Hours. 
  

   — 
  At 
  the 
  end 
  of 
  one 
  day 
  at 
  22° 
  C. 
  an 
  examination 
  of 
  the 
  

   citrated 
  blood 
  shows 
  the 
  forms 
  figured 
  in 
  lines 
  111 
  and 
  VII 
  

   of 
  the 
  plate, 
  while 
  lines 
  II 
  and 
  VI 
  show 
  those 
  seen 
  in 
  the 
  

   spleen 
  blood 
  of 
  the 
  same 
  cases 
  before 
  incubation. 
  It 
  will 
  be 
  

   seen 
  from 
  line 
  III 
  that 
  at 
  the 
  end 
  of 
  one 
  day 
  the 
  organisms 
  

   have 
  already 
  increased 
  considerably 
  in 
  size, 
  while 
  the 
  macro- 
  

   nucleus 
  is 
  also 
  larger, 
  this 
  being 
  a 
  striking 
  feature. 
  On 
  the 
  

   other 
  hand, 
  the 
  micro-nucleus 
  has 
  not 
  altered, 
  but 
  still 
  

   remains 
  small 
  and 
  rod 
  shaped. 
  The 
  forms 
  shown 
  in 
  line 
  

   VII 
  also 
  show 
  that 
  the 
  macro-nucleus, 
  in 
  addition 
  to 
  being 
  

   larger, 
  is 
  beginning 
  to 
  present 
  a 
  granular 
  appearance, 
  while 
  

   it 
  does 
  not 
  stain 
  so 
  darkly 
  as 
  in 
  the 
  original 
  spleen 
  parasites. 
  

   Further, 
  the 
  protoplasm 
  of 
  the 
  cell 
  is 
  also 
  increasing 
  in 
  

   amount 
  and 
  now 
  take 
  on 
  a 
  bluish 
  staining-, 
  and 
  has 
  a 
  very 
  

   finely 
  granular 
  appearance. 
  These 
  are 
  the 
  only 
  changes 
  met 
  

   with 
  as 
  a 
  rule 
  on 
  the 
  first 
  day. 
  

  

  