﻿OHBOMOSOMKS 
  OF 
  TUADESOANTIA 
  VIRGINIGA. 
  569 
  

  

  Figs. 
  17, 
  18.— 
  Diasters, 
  

  

  Tig. 
  19. 
  — 
  The 
  swelling 
  up 
  of 
  tiie 
  chromosomes 
  at 
  the 
  poles, 
  and 
  formation 
  

   of 
  the 
  cell 
  plate. 
  

  

  Figs. 
  20, 
  21. 
  — 
  Later 
  stage 
  in 
  swelling 
  up 
  of 
  chromosomes, 
  and 
  the 
  forma- 
  

   tion 
  of 
  nucleoli. 
  

  

  Fig. 
  23. 
  — 
  Two 
  daughter 
  nuclei 
  in 
  a 
  resting 
  condition. 
  

  

  Reduction 
  Divisions 
  (Maiotic 
  Phase). 
  

  

  Fig. 
  23 
  — 
  Resting 
  nucleus 
  of 
  pollen 
  mother 
  cell. 
  

  

  Figs. 
  24, 
  25. 
  — 
  Fibrillar 
  arrangement 
  of 
  chromatin 
  ; 
  early 
  prophase. 
  

  

  Fig. 
  26. 
  — 
  Fibrillar 
  arrangement 
  evenly 
  distributed. 
  

  

  Figs. 
  27 
  — 
  29. 
  — 
  First 
  contraction 
  figure. 
  

  

  Figs. 
  30 
  — 
  33. 
  — 
  The 
  stages 
  following 
  on 
  the 
  contraction 
  figure 
  and 
  effecting 
  

   a 
  polarisation 
  of 
  the 
  spireme. 
  Longitudinal 
  fission 
  to 
  be 
  seen. 
  

  

  Fig. 
  34. 
  — 
  Commencement 
  of 
  the 
  second 
  (synaptic) 
  contraction. 
  

  

  Figs. 
  35, 
  36. 
  — 
  Further 
  stages 
  in 
  the 
  synapsis. 
  The 
  longitudinal 
  fission 
  

   clear 
  in 
  Fig. 
  35. 
  

  

  Fig. 
  37.— 
  Loosening 
  of 
  the 
  synaptic 
  contraction. 
  

  

  Figs. 
  38 
  — 
  42. 
  — 
  Stages 
  in 
  the 
  evolution 
  of 
  the 
  chromosomes. 
  

  

  Figs. 
  43—45. 
  — 
  Illustrate 
  the 
  common 
  types 
  of 
  chromosomes 
  seen 
  during 
  

   the 
  diaster. 
  

  

  Figs. 
  46 
  — 
  48. 
  — 
  The 
  groups 
  of 
  daughter 
  chromosomes 
  showing 
  the 
  reopening 
  

   of 
  the 
  longitudinal 
  fission. 
  

  

  Figs. 
  49 
  — 
  53. 
  — 
  Various 
  figures 
  showing 
  extra-nuclear 
  chromosomes 
  left 
  

   behind 
  at 
  the 
  reconstitution 
  of 
  the 
  daughter 
  nuclei. 
  

  

  Fig. 
  55. 
  — 
  Nucleus 
  preparing 
  for 
  homotype 
  mitosis. 
  

  

  Figs. 
  56—58. 
  — 
  Stages 
  in 
  the 
  homotype 
  mitosis. 
  In 
  Fig. 
  56 
  one 
  pair 
  of 
  

   nuclei 
  are 
  seen 
  in 
  profile, 
  and 
  the 
  other 
  in 
  polar 
  view. 
  

  

  VOL. 
  48, 
  PART 
  4. 
  NEW 
  SERIES, 
  41 
  

  

  