﻿NOTES 
  ON 
  SPOROZOA. 
  159 
  

  

  of 
  the 
  envelope 
  enclosing 
  each 
  cluster 
  of 
  germs. 
  A 
  Coccidian 
  

   sporocyst 
  is 
  always 
  quite 
  definite 
  in 
  form 
  and 
  fairly 
  tough 
  

   and 
  resistant, 
  and 
  generally 
  consists 
  of 
  two 
  valves 
  which 
  

   separate 
  under 
  the 
  action 
  of 
  the 
  new 
  host's 
  digestive 
  juices 
  

   (sometimes, 
  this 
  can 
  be 
  effected 
  artificially) 
  to 
  liberate 
  the 
  

   sporozoites. 
  Nothing 
  of 
  the 
  kind 
  is 
  mentioned 
  in 
  Smith 
  and 
  

   Johnson's 
  account; 
  the 
  authors 
  simply 
  state 
  that 
  the 
  mem- 
  

   brane 
  is 
  very 
  delicate, 
  and 
  easily 
  ruptured 
  on 
  pressure. 
  As 
  

   I 
  have 
  above 
  suggested, 
  it 
  much 
  more 
  probably 
  represents 
  

   (together 
  with 
  a 
  small 
  amount 
  of 
  residual 
  material) 
  the 
  

   remains 
  of 
  a 
  daughter-schizont, 
  most 
  of 
  which 
  has 
  gone 
  to 
  

   form 
  the 
  merozoites. 
  Between 
  these 
  and 
  sporozoites, 
  in 
  the 
  

   fresh 
  condition, 
  there 
  is 
  little 
  difference, 
  so 
  that 
  I 
  need 
  only 
  

   add 
  that 
  if 
  my 
  interpretation 
  is 
  correct, 
  the 
  germs 
  in 
  Fig. 
  

   A 
  (5 
  h) 
  belong 
  to 
  the 
  former 
  category 
  and 
  not 
  to 
  the 
  latter.^ 
  

  

  Of 
  course 
  the 
  novel, 
  and 
  at 
  that 
  time 
  unexampled 
  variation 
  

   which 
  distinguishes 
  schizogony 
  in 
  Klossiella 
  from 
  the 
  usual 
  

   method, 
  might, 
  to 
  a 
  certain 
  extent, 
  mislead 
  the 
  authors 
  in 
  

   interpreting 
  their 
  observations. 
  Apart 
  from 
  this, 
  however, 
  

   the 
  above-mentioned 
  very 
  characteristic 
  facts 
  relative 
  to 
  the 
  

   general 
  course 
  of 
  development 
  of 
  a 
  Coccidian 
  parasite 
  and 
  its 
  

   relation 
  to 
  the 
  host-cell 
  ought 
  to 
  have 
  rendered 
  them 
  

   suspicious 
  in 
  accepting 
  the 
  observed 
  stages 
  as 
  constituting 
  

   sporogony. 
  As 
  it 
  happened 
  Siedlecki 
  (1. 
  c.) 
  very 
  soon 
  after- 
  

   wards 
  described 
  a 
  similar 
  modification 
  of 
  merogony 
  in 
  

   Caryotropha. 
  The 
  resemblance 
  between 
  the 
  process 
  in 
  the 
  

   two 
  genera 
  is 
  most 
  striking, 
  and 
  I 
  have 
  above 
  used 
  this 
  

   author's 
  terminology 
  in 
  interpreting 
  the 
  phase 
  as 
  it 
  occurs 
  in 
  

   Klossiella. 
  

  

  In 
  Fig. 
  B 
  are 
  reproduced 
  some 
  figures 
  of 
  Caryotropha 
  

   for 
  comparison 
  with 
  those 
  in 
  Fig. 
  A. 
  In 
  (1) 
  the 
  host- 
  cell 
  (a 
  

   spermatogonium) 
  and 
  two 
  of 
  its 
  neighbours 
  are 
  greatly 
  

   hypertrophied 
  and 
  have 
  fused 
  into 
  a 
  single 
  mass 
  containiug 
  

  

  ' 
  Unfortunate!}' 
  it 
  is 
  impossible 
  to 
  tell 
  from 
  tig. 
  6 
  (the 
  stained 
  preparation) 
  

   wlietlier 
  tiie 
  germs 
  have 
  a 
  karyosome 
  in 
  the 
  nucleus 
  or 
  not, 
  which 
  would 
  have 
  

   conclusively 
  settled 
  the 
  question. 
  

  

  