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  Mr. 
  L. 
  T. 
  Hogben. 
  

  

  and 
  Neuroterus. 
  The 
  chromosomes 
  of 
  the 
  spindle 
  come 
  more 
  closely 
  into 
  

   contact 
  till 
  they 
  form 
  a 
  compact 
  complex 
  ; 
  the 
  spindle 
  disappears, 
  the 
  chromo- 
  

   some 
  complex 
  becomes 
  more 
  or 
  less 
  spherical, 
  and 
  the 
  clear 
  area 
  occupied 
  

   before 
  by 
  the 
  nuclear 
  sap 
  is 
  gradually 
  invaded 
  by 
  yolk-laden 
  cytoplasm, 
  so 
  

   that 
  it 
  is 
  rendered 
  inconspicuous 
  (figs. 
  14-17). 
  The 
  condensation 
  of 
  spindles 
  

   in 
  the 
  late 
  ovarian 
  oocyte 
  has 
  already 
  been 
  described 
  in 
  three 
  Chalcid 
  

   genera, 
  Ageneaspis 
  (Martin), 
  Copidosoma 
  (Hegner 
  and 
  Silvestri), 
  and 
  

   Trichogramma 
  (Gatenby), 
  in 
  the 
  Cynipids 
  Andricus 
  (Hegner) 
  and 
  Neuroterus 
  

   (Hogben), 
  as 
  also 
  in 
  the 
  Braconid 
  Apanteles 
  (Hegner). 
  

  

  The 
  precise 
  stage 
  at 
  which 
  the 
  nuclear 
  membrane 
  dissolves 
  in 
  the 
  process 
  

   here 
  described 
  is 
  difficult 
  to 
  determine, 
  owing 
  to 
  the 
  sharply 
  defined 
  meniscus 
  

   separating 
  the 
  clear 
  space 
  occupied 
  by 
  the 
  nuclear 
  sap 
  and 
  the 
  surrounding 
  

   heavily 
  yolked 
  cytoplasm. 
  For 
  this 
  very 
  reason 
  it 
  can 
  be 
  said, 
  however, 
  

   with 
  some 
  assurance 
  that 
  the 
  spindle 
  fibres 
  originate 
  in 
  the 
  area 
  originally 
  

   occupied 
  by 
  the 
  resting 
  nucleus. 
  The 
  existence 
  of 
  a 
  maturation 
  spindle 
  in 
  

   the 
  ovarian 
  oocyte 
  of 
  Cynips 
  does 
  not 
  imply 
  a 
  reductive 
  division 
  in 
  the 
  

   formation 
  of 
  polar 
  bodies. 
  Eeduction 
  of 
  the 
  chromosomes 
  in 
  the 
  oocytes 
  of 
  

   the 
  agamic 
  Spring 
  females 
  of 
  Neuroterus 
  occurs, 
  but, 
  while 
  an 
  abortive 
  

   maturation 
  spindle 
  is 
  found, 
  no 
  polar 
  bodies 
  are 
  extruded 
  in 
  the 
  female- 
  

   producing 
  ova. 
  Possibly 
  the 
  same 
  holds 
  good 
  for 
  Cynips. 
  Or 
  alternatively, 
  

   if 
  polar 
  bodies 
  are 
  produced, 
  as 
  is 
  more 
  usual 
  in 
  parthenogenetic 
  ova, 
  both 
  

   divisions 
  may 
  be 
  equational, 
  and 
  a 
  subsequent 
  disjunction 
  of 
  univalents 
  may 
  

   ensue. 
  Whatever 
  be 
  the 
  behaviour 
  of 
  the 
  nucleus 
  in 
  Cynips 
  after 
  the 
  egg 
  is 
  

   laid, 
  it 
  may 
  be 
  confidently 
  asserted 
  that 
  the 
  early 
  history 
  of 
  the 
  oocyte 
  

   resembles 
  that 
  of 
  other 
  Hymenoptera 
  parasitica, 
  and 
  the 
  chromosomes, 
  which 
  

   are 
  seen 
  as 
  the 
  maturation 
  spindle 
  of 
  the 
  ovarian 
  oocyte, 
  are 
  bivalent 
  in 
  

   character. 
  

  

  Rhodites 
  rosce. 
  

  

  Rhodites 
  rosce, 
  which 
  is 
  responsible 
  for 
  the 
  Bedeguar 
  Bose 
  gall 
  on 
  the 
  wild 
  

   rose, 
  is 
  too 
  familiar 
  to 
  merit 
  introduction. 
  It 
  has 
  already 
  been 
  made 
  the 
  

   subject 
  of 
  cytological 
  researches 
  by 
  two 
  workers, 
  but, 
  since 
  their 
  conclusions 
  

   are 
  at 
  variance, 
  and 
  do 
  not 
  seem 
  to 
  show 
  an 
  appreciation 
  of 
  the 
  peculiar 
  

   history 
  of 
  the 
  nucleus 
  in 
  the 
  later 
  maturation 
  prophases 
  of 
  the 
  Cynipid 
  egg, 
  

   there 
  is 
  good 
  reason 
  for 
  completing 
  and 
  criticising 
  the 
  accounts 
  hitherto 
  

   given. 
  

  

  Henking 
  (1892) 
  found 
  that, 
  in 
  the 
  full-grown 
  oocytes, 
  shortly 
  before 
  

   laying, 
  nine 
  chromosomes 
  (which 
  he 
  concluded 
  to 
  be 
  bivalent), 
  are 
  present. 
  

   Two 
  polar 
  bodies 
  are 
  formed, 
  and 
  show 
  9-10 
  chromosomes, 
  as 
  does 
  also 
  the 
  

   anaphase 
  of 
  the 
  segmentation 
  nucleus. 
  According 
  to 
  this 
  author, 
  the 
  

   segmentation 
  nucleus, 
  after 
  a 
  period 
  of 
  rest, 
  during 
  which 
  its 
  staining 
  

  

  