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  Mr. 
  L. 
  T. 
  Hogben. 
  

  

  the 
  process 
  loosely 
  as 
  " 
  amitotic." 
  Martin 
  says 
  that 
  the 
  mass 
  formed 
  by 
  the 
  

   condensation 
  of 
  the 
  maturation 
  spindle 
  " 
  divides 
  in 
  polar 
  body 
  formation 
  

   without 
  the 
  presence 
  of 
  spindle 
  fibres 
  or 
  asters." 
  It 
  may 
  be 
  confidently 
  

   predicted 
  that 
  the 
  formation 
  of 
  polar 
  bodies 
  by 
  a 
  similarly 
  atypical 
  procedure 
  

   will 
  be 
  demonstrated 
  by 
  subsequent 
  research 
  in 
  other 
  forms, 
  where 
  the 
  

   history 
  of 
  the 
  egg 
  nucleus 
  shortly 
  before 
  deposition 
  is 
  comparable. 
  

  

  I 
  have 
  not 
  investigated 
  the 
  maturation 
  of 
  the 
  egg 
  in 
  Bhodites. 
  The 
  

   crucial 
  difference 
  between 
  the 
  rival 
  conclusions 
  of 
  the 
  two 
  authors 
  referred 
  

   to 
  lies 
  in 
  their 
  statements 
  regarding 
  the 
  segmentation 
  mitoses, 
  which, 
  

   according 
  to 
  Henking 
  display 
  18-20, 
  according 
  to 
  Schleip 
  10-12 
  chromo- 
  

   somes. 
  Concerning 
  the 
  latter 
  view, 
  I 
  would 
  here 
  submit 
  (1) 
  that 
  Schleip 
  

   failed 
  to 
  appreciate 
  the 
  double 
  nature 
  of 
  the 
  chromosomes 
  which 
  he 
  counted 
  

   (together 
  with 
  karyosomes) 
  in 
  the 
  oocyte 
  nucleus 
  ; 
  (2) 
  that 
  a 
  study 
  of 
  the 
  

   nuclear 
  divisions 
  in 
  the 
  segmenting 
  egg 
  does 
  not 
  provide 
  such 
  a 
  satisfactory 
  

   basis 
  for 
  counting 
  the 
  chromosomes, 
  when 
  small 
  and 
  numerous, 
  as 
  do 
  the 
  

   oogonia 
  and 
  somatic 
  tissues 
  of 
  the 
  pupa 
  ; 
  (3) 
  it 
  is 
  easier 
  to 
  underestimate 
  the 
  

   number 
  of 
  chromosomes 
  than 
  to 
  count 
  more 
  than 
  are 
  actually 
  present 
  ; 
  

   (4) 
  were 
  the 
  chromosome 
  cycle 
  in 
  Bhodites 
  such 
  as 
  set 
  forth 
  by 
  Schleip, 
  

   it 
  would 
  be 
  remarkably 
  unlike 
  that 
  of 
  other 
  Cynipids, 
  notably, 
  Cynips 
  

   kollari. 
  Furthermore, 
  the 
  last-named 
  investigator 
  seems 
  to 
  me 
  to 
  have 
  

   approached 
  the 
  subject 
  in 
  an 
  attitude 
  suggestive 
  rather 
  of 
  propaganda 
  than 
  

   of 
  scientific 
  impartiality, 
  and 
  appears 
  over-anxious 
  to 
  show 
  that 
  Henking's 
  

   conclusions 
  are 
  mistaken, 
  because 
  of 
  their 
  similarity 
  to 
  those 
  of 
  Petrunkewitsch 
  

   with 
  respect 
  to 
  the 
  drone 
  bee. 
  He 
  criticises 
  the 
  alleged 
  doubling 
  {i.e., 
  dis- 
  

   junction) 
  of 
  chromosomes 
  during 
  interkinesis, 
  on 
  the 
  ground 
  that 
  it 
  does 
  not 
  

   fall 
  in 
  with 
  accepted 
  views 
  regarding 
  the 
  persistent 
  individuality 
  of 
  the 
  

   chromosomes 
  ; 
  but 
  the 
  facts 
  of 
  synapsis 
  alone 
  vitiate 
  such 
  an 
  objection 
  ; 
  and 
  

   the 
  fact 
  that 
  he 
  finds 
  only 
  six 
  chromosomes 
  in 
  the 
  blastoderm 
  stage 
  confirms 
  

   my 
  belief 
  that 
  his 
  preparations 
  were 
  not 
  satisfactory. 
  The 
  events 
  of 
  the 
  

   chromosome 
  cycle 
  in 
  Bhodites, 
  then, 
  may 
  be 
  summarised 
  as 
  follows 
  : 
  (1) 
  the 
  

   somatic 
  and 
  oogonial 
  mitoses 
  show 
  18 
  chromosomes; 
  (2) 
  parasynapsis 
  

   probably 
  occurs 
  in 
  the 
  young 
  oocyte 
  ;* 
  (3) 
  at 
  the 
  conclusion 
  of 
  the 
  growth 
  

   period 
  the 
  diploid 
  number 
  reappears 
  ; 
  (4) 
  these 
  filaments 
  then 
  conjugate, 
  so 
  

   that 
  the 
  full-grown 
  oocytes 
  show 
  nine 
  chromosomes, 
  the 
  origin 
  of 
  which 
  is 
  

   betrayed 
  by 
  their 
  double 
  character 
  ; 
  (5) 
  the 
  haploid 
  number 
  of 
  bivalents 
  is 
  

   arranged 
  on 
  an 
  asterless 
  spindle, 
  which 
  passes 
  through 
  the 
  stages 
  of 
  con- 
  

   densation 
  ; 
  (6) 
  the 
  segmentation 
  nucleus, 
  according 
  to 
  Henking, 
  contains 
  

  

  * 
  It 
  is 
  difficult 
  to 
  interpret 
  the 
  restoration 
  of 
  the 
  diploid 
  number 
  by 
  the 
  longitudina 
  

   splitting 
  of 
  the 
  pachytene 
  threads 
  without 
  assuming 
  that 
  the 
  latter 
  arise 
  by 
  the 
  

   side-by-side 
  union 
  of 
  leptotene 
  threads. 
  

  

  