﻿Studies 
  on 
  Synapsis, 
  

  

  277 
  

  

  stage 
  rimy-shaped 
  plasmosomes 
  are 
  frequently 
  seen 
  as 
  in 
  Synergm 
  ;* 
  and, 
  

   as 
  earlier 
  described, 
  the 
  plasmosorne 
  of 
  the 
  preceding 
  stage 
  is 
  seen 
  to 
  be 
  

   vacuolated 
  in 
  preparation 
  for 
  its 
  dissolution 
  into 
  ring-like 
  bodies. 
  This 
  

   probably 
  accounts 
  for 
  the 
  fact 
  that 
  Schleip 
  is 
  able 
  to 
  count 
  from 
  10 
  to 
  

   12 
  chromosomes 
  (doubles), 
  whereas 
  I 
  have 
  never 
  counted 
  more 
  than 
  nine, 
  

   thus 
  agreeing 
  with 
  Henking, 
  who 
  also 
  regards 
  these 
  chromosomes 
  as 
  

   bivalents. 
  Those 
  who 
  have 
  studied 
  the 
  late 
  maturation 
  prophases 
  of 
  the 
  

   Cynipidte 
  would 
  anticipate 
  from 
  these 
  phenomena 
  the 
  subsequent 
  formation 
  

   of 
  an 
  abortive 
  spindle 
  such 
  as 
  has 
  been 
  demonstrated 
  in 
  Andricus, 
  Cynips, 
  

   and 
  Neuroterus. 
  Neither 
  Henking 
  nor 
  Schleip 
  have 
  followed 
  up 
  the 
  suc- 
  

   ceeding 
  stages 
  in 
  detail. 
  According 
  to 
  the 
  former, 
  who 
  gives 
  a 
  much 
  more 
  

   thorough 
  survey 
  of 
  the 
  data, 
  " 
  lange 
  bleiben 
  die 
  Chromosomen 
  jedoch 
  nicht 
  

   von 
  einander 
  getrennt. 
  In 
  den 
  etwas 
  alteren 
  Eiern 
  bemerkt 
  man 
  namlich 
  

   dass 
  deren 
  mehrere 
  zusammen 
  zu 
  treten 
  beginnen, 
  entweder 
  zu 
  Klumpen, 
  

   oder 
  auch 
  Ketten. 
  Je 
  mehr 
  das 
  Ei 
  reift, 
  um 
  so 
  mehr 
  schreitet 
  dieser 
  

   Process 
  fort, 
  so 
  das 
  schliesslich 
  alle 
  Chromosomen 
  zu 
  einem 
  gemeinsamen 
  

   Ballen 
  vereinigt 
  sind." 
  Later 
  he 
  observes 
  " 
  der 
  farblose 
  Kernraum 
  ' 
  an 
  

   Volumen 
  eingebiisst 
  hat." 
  Henking 
  does 
  not 
  mention 
  the 
  presence 
  of 
  

   spindle 
  fibres, 
  but, 
  in 
  reality, 
  a 
  very 
  clear 
  spindle 
  is 
  (figs. 
  35-37) 
  formed, 
  

   without 
  either 
  aster 
  or 
  centriole, 
  and 
  upon 
  this 
  spindle 
  the 
  bivalent 
  

   chromosomes 
  arrange 
  themselves 
  in 
  a 
  parallel 
  series 
  in 
  the 
  equatorial 
  plane. 
  

  

  The 
  mitotic 
  figure 
  now 
  passes 
  through 
  the 
  stages 
  of 
  condensation 
  ; 
  the 
  

   chromosome 
  complex 
  (figs. 
  37, 
  38), 
  at 
  first 
  elongated 
  with 
  respect 
  to 
  the 
  

   axis 
  of 
  the 
  spindle, 
  becomes 
  spherical 
  ; 
  the 
  spindle 
  itself 
  disappears, 
  and 
  

   the 
  so-called 
  nucleus 
  becomes 
  lost 
  in 
  the 
  surrounding 
  yolk. 
  One 
  further 
  

   point 
  that 
  may 
  be 
  mentioned 
  is 
  that 
  the 
  karyosome 
  disintegrates 
  into 
  a 
  

   number 
  of 
  granules 
  that 
  surround 
  it. 
  

  

  The 
  discovery 
  of 
  a 
  precociously 
  formed 
  and 
  interrupted 
  maturation 
  

   spindle 
  in 
  late 
  ovarian 
  oocytes 
  of 
  Rhodites 
  is 
  of 
  some 
  cytological 
  interest, 
  as 
  

   throwing 
  light 
  on 
  the 
  character 
  of 
  the 
  peculiar 
  mitotic 
  phenomena 
  of 
  

   ookinesis 
  in 
  certain 
  Hymenoptera, 
  and 
  confirming 
  the 
  conclusions 
  I 
  have 
  

   elsewhere 
  expressed 
  in 
  regard 
  to 
  the 
  figures 
  originally 
  described 
  by 
  Hegner, 
  

   based 
  on 
  previous 
  work 
  on 
  Neuroterus 
  ; 
  for, 
  according 
  to 
  Henking's 
  account 
  

   the 
  preparation 
  of 
  the 
  polar 
  nuclei 
  is 
  very 
  much 
  like 
  the 
  corresponding 
  

   process 
  described 
  by 
  Doncaster 
  in 
  the 
  eggs 
  of 
  Neuroterus 
  and 
  of 
  a 
  type 
  

   differing 
  widely 
  from 
  the 
  ordinary 
  form 
  of 
  mitosis. 
  An 
  atypical 
  formation 
  

   of 
  polar 
  bodies 
  in 
  Trichogramma 
  and 
  Ageniaspis, 
  which 
  also 
  show 
  abortive 
  

   spindles 
  in 
  the 
  ovarian 
  egg, 
  has 
  been 
  referred 
  to 
  earlier. 
  Qatenby 
  describes 
  

  

  * 
  Vide 
  infra. 
  

  

  