﻿THE 
  MAIOTIO 
  PHASE 
  IN 
  ANIMALS 
  AND 
  PLANTS. 
  503 
  

  

  pi-etation. 
  A 
  simple 
  inspection 
  of 
  the 
  figures 
  that 
  accompany 
  

   and 
  illustrate 
  his 
  paper 
  suffices 
  to 
  show 
  that 
  the 
  very 
  stages 
  

   that 
  we 
  regard 
  as 
  of 
  critical 
  importance 
  are 
  lacking. 
  More- 
  

   over, 
  his 
  drawings 
  do 
  not 
  carry 
  conviction. 
  They 
  are 
  either 
  

   very 
  schematic, 
  or 
  else 
  they 
  are 
  based 
  on 
  preparations 
  in 
  

   which 
  all 
  the 
  finer 
  details 
  of 
  structure 
  have 
  been 
  inadequately 
  

   preserved. 
  And 
  finally, 
  in 
  the 
  text, 
  he 
  gives 
  no 
  evidence 
  of 
  

   having 
  paid 
  special 
  attention 
  to 
  the 
  admittedly 
  difficult 
  stages 
  

   wliicli 
  alone 
  contain 
  the 
  solution 
  of 
  the 
  problem. 
  

  

  As 
  long 
  ago 
  as 
  1894 
  Belajeff, 
  in 
  a 
  paper 
  published 
  in 
  

   'Flora,' 
  on 
  Iris 
  and 
  Larix, 
  maintained 
  that 
  a 
  true 
  reduc- 
  

   tion 
  occurred 
  in 
  these 
  plants. 
  But 
  he 
  was 
  led, 
  by 
  the 
  

   emphasis 
  laid 
  by 
  him 
  on 
  the 
  figures 
  exhibited 
  during 
  the 
  

   later 
  stages 
  of 
  the 
  process, 
  to 
  attribute 
  the 
  real 
  reduction 
  

   (qualitative) 
  to 
  the 
  homotype 
  mitosis, 
  just 
  as 
  some 
  of 
  the 
  

   Freiburg 
  investigators 
  had 
  done. 
  Strasburger 
  and 
  others 
  

   have 
  since 
  shown 
  this 
  position 
  to 
  be 
  untenable, 
  and 
  the 
  con- 
  

   viction 
  has 
  slowly 
  grown 
  up 
  that 
  the 
  second 
  (homotype) 
  

   mitosis 
  — 
  in 
  plants, 
  at 
  any 
  rate 
  — 
  is 
  certainly 
  associated 
  with 
  a 
  

   longitudinal 
  fission, 
  and 
  not 
  with 
  a 
  transverse 
  or 
  qualitative 
  

   distribution. 
  

  

  As 
  these 
  lines 
  are 
  being 
  written 
  we 
  have 
  received 
  from 
  

   Professor 
  Strasburger 
  ^ 
  a 
  memoir 
  dealing 
  with 
  reduction 
  

   divisions. 
  The 
  results 
  are 
  in 
  substantial 
  agreement 
  with 
  

   those 
  contained 
  in 
  our 
  previous 
  communication, 
  and 
  which 
  

   are 
  here 
  presented 
  in 
  an 
  amplified 
  form. 
  The 
  case 
  of 
  

   Graltonia, 
  as 
  described 
  by 
  Strasburger," 
  is 
  especially 
  in- 
  

  

  ' 
  Strasburger, 
  E., 
  " 
  Ueber 
  Reductions 
  Theilung.," 
  ' 
  Sitz. 
  ber. 
  H. 
  K. 
  Preus. 
  

   Akad. 
  d. 
  Wiss.,' 
  24 
  Miirz, 
  1904. 
  

  

  2 
  We 
  note 
  on 
  p. 
  6 
  of 
  the 
  separate 
  copy 
  tliat 
  tlie 
  author 
  seems 
  perhaps 
  to 
  

   have 
  not 
  quite 
  understood 
  onr 
  position, 
  as 
  taken 
  up 
  in 
  the 
  preliminary 
  note 
  read 
  

   before 
  the 
  Royal 
  Society, 
  The 
  closed 
  rings 
  (g 
  e 
  s 
  c 
  h 
  1 
  o 
  s 
  s 
  e 
  n 
  e 
  s 
  c 
  h 
  1 
  e 
  i 
  f 
  e 
  n) 
  were 
  

   described 
  by 
  us 
  being 
  most 
  common, 
  but 
  our 
  diagrammatic 
  fig. 
  4, 
  in 
  the 
  note 
  

   referred 
  to, 
  shows 
  clearly 
  one 
  bivalent 
  cliromoson 
  e 
  with 
  both 
  ends 
  free, 
  which 
  

   proves 
  we 
  liad 
  not 
  overlooked 
  these 
  case<. 
  Tlie 
  regularity 
  of 
  the 
  loops 
  is 
  

   much 
  greater 
  in 
  animals 
  than 
  in 
  plants, 
  hence 
  perhaps 
  the 
  emphasis 
  that 
  was 
  

   put 
  upon 
  these 
  figures 
  in 
  the 
  note, 
  which 
  had 
  very 
  briefly 
  to 
  indicate 
  the 
  

   general 
  results 
  of 
  the 
  investigation 
  as 
  a 
  whole 
  rather 
  than 
  to 
  discuss 
  details. 
  

  

  