﻿THE 
  MAIOTIC 
  PHASE 
  IN 
  ANIMALS 
  AND 
  PLANTS. 
  517 
  

  

  siders 
  that 
  the 
  sph't 
  really 
  represents 
  the 
  separation 
  of 
  the 
  

   threads 
  that 
  have 
  just 
  before 
  fused. 
  The 
  longitudinal 
  

   fission 
  therefore, 
  strictly 
  speaking, 
  would 
  not 
  exist. 
  The 
  

   separated 
  halves 
  of 
  the 
  'Hhick 
  spireme 
  ^^ 
  contract 
  and 
  give 
  

   rise 
  to 
  the 
  two 
  halves 
  of 
  each 
  bivalent 
  chromosome, 
  when, 
  

   by 
  the 
  transverse 
  segmentation 
  of 
  the 
  spireme 
  thread, 
  they 
  

   can 
  be 
  identified 
  as 
  distinct 
  individuals. 
  

  

  We 
  have 
  tried 
  to 
  state 
  M. 
  Gregoire's 
  position 
  as 
  fairly 
  as 
  

   we 
  can, 
  and 
  if 
  we 
  have 
  correctly 
  apprehended 
  his 
  meaning 
  

   we 
  find 
  ourselves 
  wholly 
  unable 
  to 
  agree 
  with 
  him. 
  

  

  It 
  appears 
  to 
  us 
  that 
  two 
  series 
  of 
  events 
  have 
  been 
  con- 
  

   fused. 
  There 
  is 
  not 
  onl^^ 
  one, 
  but 
  there 
  are 
  two 
  contraction 
  

   figures. 
  In 
  the 
  first 
  one, 
  which 
  Professor 
  Gregoire 
  seems 
  to 
  

   regard 
  as 
  the 
  synaptic 
  figure, 
  we 
  have 
  been 
  able 
  to 
  trace 
  the 
  

   spireme 
  continuously 
  ; 
  and 
  there 
  cannot 
  exist 
  the 
  slightest 
  

   doubt 
  but 
  that, 
  as 
  it 
  emerges 
  from 
  this 
  figure, 
  the 
  longitudinal 
  

   fission 
  occurs 
  as 
  we 
  have 
  described. 
  It 
  seems 
  to 
  us 
  that 
  

   Gregoire 
  (and 
  Berghs) 
  has 
  either 
  omitted 
  to 
  observe 
  the 
  

   fission 
  and 
  has 
  only 
  seen 
  the 
  re-fusion 
  of 
  the 
  split 
  thread, 
  

   or 
  else 
  he 
  interprets 
  the 
  earlier 
  stage 
  in 
  which 
  the 
  fission 
  is 
  

   as 
  yet 
  incomplete 
  in 
  a 
  sense 
  opposite 
  to 
  that 
  in 
  which 
  we, 
  

   together 
  with 
  most 
  other 
  observers, 
  regard 
  it. 
  But 
  it 
  is 
  

   rather 
  difficult 
  to 
  follow 
  the 
  account 
  given 
  by 
  Gregoire, 
  

   inasmuch 
  as 
  he 
  makes 
  no 
  mention 
  of 
  the 
  second 
  contraction 
  

   (which 
  we 
  I'egard 
  as 
  the 
  essential 
  synaptic 
  one) 
  wherein 
  the 
  

   lateral 
  approximations 
  of 
  the 
  spireme 
  occur. 
  For 
  we 
  can 
  

   hardly 
  suppose 
  that 
  this 
  contraction 
  can 
  have 
  been 
  confused 
  

   with 
  the 
  earlier 
  one, 
  and 
  yet 
  apart 
  from 
  some 
  such 
  assump- 
  

   tion 
  it 
  is 
  difficult 
  to 
  reconcile 
  the 
  differences 
  between 
  our 
  

   results. 
  Moreover, 
  Gregoire's 
  account 
  of 
  course 
  excludes 
  

   the 
  existence 
  of 
  a 
  longitudinal 
  fission 
  in 
  the 
  approximated 
  

   lengths 
  of 
  the 
  now 
  differentiating 
  chromosomes, 
  since 
  he 
  

   identifies 
  these 
  lengths 
  with 
  the 
  products 
  of 
  that 
  " 
  longitu- 
  

   dinal 
  fission" 
  (approximation 
  according 
  to 
  him) 
  which 
  occurred 
  

   at 
  an 
  earlier 
  period. 
  And 
  yet 
  traces 
  of 
  this 
  fission 
  can 
  be 
  

   seen 
  at 
  all 
  the 
  stages 
  under 
  consideration. 
  

  

  M. 
  Gregoire 
  appeals 
  to 
  the 
  figures 
  in 
  M. 
  Berghs' 
  memoir 
  

  

  