﻿THE 
  DEVELOPMENT 
  OF 
  FLAGELLATED 
  ORGANISMS. 
  369 
  

  

  sion 
  lenSj 
  as 
  in 
  tlie 
  original 
  specimens^ 
  as 
  many 
  as 
  fifty 
  or 
  

   more 
  were 
  sometimes 
  seen 
  in 
  the 
  same 
  area 
  in 
  those 
  from 
  the 
  

   cultures. 
  Moreover^ 
  divisional 
  forms^ 
  which 
  are 
  rare 
  in 
  fresh 
  

   spleen 
  blood, 
  appeared 
  in 
  very 
  large 
  numbers 
  in 
  the 
  cultures 
  

   after 
  from 
  one 
  to 
  three 
  days, 
  thus 
  allowing 
  the 
  modes 
  of 
  

   division 
  to 
  be 
  much 
  more 
  easily 
  studied. 
  

  

  Divisional 
  Forms 
  without 
  Development. 
  

  

  The 
  divisional 
  forms, 
  which 
  occur 
  in 
  great 
  numbers 
  in 
  

   cultures 
  at 
  27° 
  C, 
  are 
  of 
  two 
  kinds. 
  The 
  first 
  is 
  a 
  simple 
  

   subdivision 
  of 
  the 
  small 
  oval 
  parasites 
  into 
  two, 
  both 
  the 
  

   macro- 
  and 
  the 
  micro-nucleus 
  first 
  dividing", 
  and 
  then 
  the 
  body 
  

   of 
  the 
  cell 
  splitting 
  into 
  two, 
  the 
  cleavage 
  beginning 
  at 
  one 
  

   end, 
  so 
  that 
  just 
  before 
  they 
  separate 
  they 
  remain 
  attached 
  

   only 
  by 
  the 
  other 
  poles. 
  This 
  mode 
  of 
  division 
  is 
  illus- 
  

   trated 
  in 
  line 
  I 
  of 
  the 
  plate, 
  figs. 
  1 
  to 
  4. 
  These 
  forms 
  can 
  be 
  

   found 
  in 
  small 
  numbers 
  by 
  long 
  search 
  in 
  films 
  of 
  blood 
  

   obtained 
  by 
  spleen 
  puncture 
  when 
  numerous 
  parasites 
  are 
  

   present, 
  but 
  they 
  form 
  only 
  a 
  very 
  small 
  proportion 
  of 
  the 
  

   total 
  number 
  of 
  organisms 
  seen. 
  On 
  the 
  other 
  hand, 
  in 
  

   cultures 
  they 
  are 
  present 
  in 
  very 
  much 
  larger 
  numbers, 
  

   several 
  in 
  various 
  stages 
  being 
  often 
  seen 
  in 
  a 
  single 
  field 
  of 
  

   the 
  microscope. 
  

  

  The 
  second 
  mode 
  of 
  division 
  is 
  a 
  multiple 
  one, 
  as 
  shown 
  in 
  

   line 
  I, 
  figs. 
  5 
  to 
  8. 
  The 
  macro- 
  and 
  micro-nucleus 
  divides 
  

   a 
  number 
  of 
  times, 
  as 
  in 
  fig. 
  6, 
  instead 
  of 
  only 
  once, 
  the 
  

   outline 
  of 
  the 
  cell 
  becoming 
  less 
  definite, 
  until 
  eventually 
  the 
  

   appearance 
  shown 
  in 
  fig. 
  7 
  is 
  reached, 
  in 
  which 
  a 
  number 
  of 
  

   very 
  small 
  nuclei 
  arranged 
  in 
  pairs 
  of 
  a 
  small 
  and 
  a 
  large 
  

   kind 
  enclosed 
  in 
  a 
  zoogloea-like 
  material 
  is 
  seen. 
  Next 
  these 
  

   enlarge 
  gradually, 
  and 
  each 
  pair 
  becomes 
  surrounded 
  by 
  a 
  

   faint 
  capsule, 
  which 
  becomes 
  more 
  and 
  more 
  distinct 
  with 
  the 
  

   growth 
  of 
  each 
  young 
  form, 
  until 
  the 
  characteristic 
  groups 
  of 
  

   the 
  oval 
  bi-nucleated, 
  fully-grown 
  spleen 
  parasites 
  result, 
  as 
  

   shown 
  in 
  fig. 
  8 
  of 
  line 
  II 
  of 
  the 
  plate, 
  which 
  are 
  not 
  very 
  

   rarely 
  seen 
  in 
  good 
  specimens 
  of 
  spleen 
  puncture 
  blood. 
  

  

  