﻿Studies 
  on 
  Synapsis. 
  

  

  317 
  

  

  chromosomes 
  is 
  in 
  reality 
  a 
  plasmosome. 
  To 
  test 
  this 
  possibility, 
  the 
  

   oogenesis 
  of 
  Gryllus 
  domesticus 
  was 
  investigated, 
  and 
  the 
  results 
  justified 
  

   anticipation. 
  While 
  insufficient 
  material 
  was 
  studied 
  to 
  yield 
  a 
  complete 
  

   account 
  of 
  the 
  synaptic 
  phase, 
  it 
  may 
  be 
  added 
  that 
  follicular 
  mitoses 
  clearly 
  

   indicate 
  that 
  the 
  heterochromosomes 
  of 
  the 
  female 
  are 
  paired. 
  No 
  more 
  

   need 
  be 
  said 
  on 
  this 
  matter, 
  since 
  Gutherz 
  (16) 
  has 
  denied 
  the 
  authenticity 
  

   of 
  Buchner's 
  observations, 
  and 
  Mohr 
  has 
  based 
  a 
  very 
  destructive 
  criticism 
  of 
  

   Buchner's 
  theory 
  of 
  the 
  trophic 
  function 
  of 
  accessory 
  chromosomes 
  on 
  his 
  

   own 
  researches 
  into 
  the 
  oogenesis 
  of 
  Leptophyes 
  (13). 
  An 
  inspection 
  of 
  

   Buchner's 
  figures 
  of 
  badly 
  fixed 
  preparations, 
  evidently 
  overstained 
  in 
  iron 
  

   hsematoxylin, 
  will 
  suffice 
  to 
  vindicate 
  Vejdovsky's 
  (17) 
  comment 
  that 
  his 
  

   " 
  Angaben 
  . 
  und 
  bildlichen 
  Darstellungen 
  der 
  ganze 
  Keifungsperiode 
  der 
  

   Grylluseier 
  sind 
  ganz 
  wertlos." 
  

  

  A 
  point 
  of 
  more 
  general 
  significance, 
  however, 
  arises 
  in 
  this 
  connection. 
  

   Various 
  authors 
  appear 
  to 
  assume 
  that 
  the 
  nuclear 
  (so-called 
  chromatin) 
  

   particles, 
  formed 
  during 
  the 
  growth 
  period 
  of 
  the 
  egg 
  and 
  ejected 
  into 
  the 
  

   surrounding 
  cytoplasm, 
  are 
  derived 
  from 
  the 
  chromatin 
  reticulum 
  ; 
  and 
  the 
  

   question 
  of 
  the 
  bearing 
  of 
  these 
  phenomena, 
  on 
  Boveri's 
  theory 
  of 
  persistent 
  

   individuality, 
  has 
  recently 
  been 
  raised 
  by 
  Gatenby 
  (18), 
  according 
  to 
  whom 
  

   these 
  particles 
  in 
  Apanteles 
  are 
  identical 
  in 
  all 
  their 
  reactions 
  with 
  

   chromatin 
  itself. 
  It 
  might 
  be 
  pointed 
  out, 
  in 
  reply, 
  that 
  chromosomal 
  

   structures 
  themselves 
  are 
  not 
  identical 
  in 
  all 
  their 
  staining 
  reactions, 
  and 
  

   the 
  existence 
  of 
  a 
  technical 
  diagnosis 
  of 
  " 
  chromatin 
  " 
  by 
  staining 
  is 
  doubtful. 
  

   It 
  is 
  well 
  known 
  that 
  physical 
  differential 
  staining 
  is 
  a 
  process 
  in 
  which 
  a 
  

   large 
  number 
  of 
  factors 
  participate, 
  such 
  as 
  the 
  elasticity, 
  permeability, 
  

   size, 
  and 
  fixation 
  of 
  the 
  material, 
  the 
  diffusibility 
  and 
  concentration 
  of 
  the 
  

   dye, 
  the 
  period 
  over 
  which 
  and 
  the 
  temperature 
  at 
  which 
  the 
  experiment 
  is 
  

   conducted. 
  Thus 
  substances 
  of 
  identical 
  chemical 
  constitution 
  can 
  be 
  

   differentially 
  stained, 
  while 
  conversely 
  dissimilar 
  compounds 
  may 
  be 
  dyed 
  

   alike. 
  Clearly, 
  then, 
  the 
  only 
  crucial 
  test 
  available 
  is 
  continuity 
  or 
  discontinuity 
  

   of 
  structure. 
  The 
  suggestion 
  is 
  here 
  advanced 
  that 
  further 
  study 
  would 
  

   reveal 
  the 
  origin 
  of 
  the 
  so-called 
  chromatin 
  granules 
  emitted 
  from 
  the 
  

   nucleus 
  at 
  the 
  diffuse 
  stage 
  in 
  the 
  plasmosome 
  of 
  forms 
  other 
  than 
  

   Periplaneta, 
  and 
  a 
  reconsideration 
  of 
  previous 
  preparations 
  confirms 
  this 
  

   belief, 
  as 
  far 
  as 
  the 
  Cynipids 
  are 
  concerned. 
  

  

  As 
  one 
  writer 
  on 
  the 
  subject 
  has 
  commented 
  felicitously, 
  chromatin 
  is 
  a 
  

   morphological 
  rather 
  than 
  a 
  specific 
  chemical 
  substance 
  : 
  morphologically 
  

   there 
  is 
  no 
  adequate 
  evidence 
  of 
  continuity 
  of 
  structure 
  between 
  the 
  

   chromosomes 
  and 
  the 
  plasmosome, 
  directly 
  or 
  indirectly, 
  as 
  a 
  study 
  of 
  the 
  

   telophase 
  demonstrates. 
  It 
  is 
  for 
  those 
  who 
  like 
  Schaxel(19) 
  speak 
  of 
  the 
  

  

  