﻿MATURATION, 
  ETC., 
  OP 
  THE 
  EGG 
  OF 
  THE 
  AXOLOTL. 
  461 
  

  

  develops 
  a 
  system 
  of 
  bright, 
  radiating 
  lines. 
  These 
  lines 
  

   appear 
  equally 
  well 
  whether 
  the 
  preparation 
  is 
  covered 
  by 
  a 
  

   glass 
  or 
  not. 
  I 
  soon 
  came 
  to 
  the 
  conclusion 
  that 
  the 
  bright 
  

   lines 
  were 
  tracts 
  of 
  albumen 
  left 
  between 
  tubular 
  outgrowths 
  

   of 
  the 
  vacuole, 
  though 
  it 
  is 
  not 
  very 
  easy 
  to 
  make 
  this 
  out 
  in 
  

   this 
  particular 
  experiment. 
  In 
  other 
  cases, 
  however, 
  to 
  be 
  

   described 
  in 
  a 
  moment, 
  this 
  can 
  be 
  clearly 
  seen 
  to 
  be 
  so. 
  If 
  

   carmine 
  particles 
  are 
  placed 
  in 
  the 
  albumen 
  they 
  may 
  be 
  

   observed 
  to 
  stream 
  towards 
  the 
  crystal. 
  

  

  As 
  the 
  crystal 
  continues 
  to 
  dissolve 
  the 
  solution 
  approaches 
  

   the 
  saturation 
  point 
  ; 
  a 
  thick 
  brown 
  ring 
  or 
  wall 
  of 
  precipi- 
  

   tated 
  albumen 
  is 
  then 
  formed 
  round 
  the 
  central 
  vacuole. 
  

   Through 
  this, 
  however, 
  the 
  solution 
  passes, 
  and 
  there 
  are 
  

   produced 
  outside 
  the 
  wall 
  a 
  number 
  of 
  fine 
  rays 
  of 
  precipi- 
  

   tate. 
  This 
  " 
  diffusion 
  aster," 
  as 
  I 
  will 
  term 
  it 
  to 
  distinguish 
  

   it 
  from 
  the 
  other 
  or 
  " 
  excurrent 
  aster," 
  is 
  of 
  course 
  identical 
  

   with 
  the 
  structure 
  described 
  by 
  Fischer 
  under 
  the 
  title 
  of 
  

   " 
  Selbststrahlung." 
  Both 
  kinds 
  of 
  aster 
  are 
  transitory 
  and 
  

   soon 
  dissolve 
  in 
  the 
  albumen. 
  

  

  The 
  experiment 
  may 
  be 
  varied 
  by 
  using 
  instead 
  of 
  the 
  

   ammonium 
  sulphate 
  crystal 
  a 
  drop 
  of 
  glycerin, 
  or 
  glycerin 
  

   and 
  albumen, 
  or 
  glycerin 
  and 
  sublimate 
  ; 
  or 
  again 
  a 
  small 
  

   particle 
  of 
  dried 
  gum, 
  the 
  gum 
  being 
  either 
  used 
  pure 
  or 
  with 
  

   the 
  previous 
  admixture 
  of 
  potassium 
  carbonate, 
  picric 
  acid, 
  

   or 
  ammonium 
  sulphate. 
  The 
  result 
  is 
  the 
  same 
  except 
  that 
  

   when 
  the 
  substance 
  employed 
  is 
  a 
  precipitating 
  reagent 
  the 
  

   radiating 
  lines 
  of 
  albumen 
  between 
  the 
  tubular 
  outgrowths 
  

   become 
  fixed. 
  With 
  some 
  substances, 
  chromic 
  for 
  example, 
  I 
  

   found 
  that 
  only 
  the 
  diffusion 
  aster 
  could 
  be 
  produced. 
  

  

  I 
  found 
  subsequently 
  that 
  very 
  much 
  better 
  results 
  could 
  

   be 
  obtained 
  by 
  employing 
  a 
  thin 
  layer 
  of 
  albumen 
  ; 
  using 
  

   these, 
  beautiful 
  asters 
  can 
  be 
  made 
  with 
  a 
  drop 
  of 
  sublimate, 
  

   picric, 
  or 
  ammonium 
  sulphate. 
  Although 
  the 
  layer 
  of 
  albumen 
  

   is 
  exceedingly 
  thin, 
  still 
  I 
  believe 
  that 
  even 
  here 
  the 
  out- 
  

   growths 
  take 
  place 
  in 
  the 
  thickness 
  of 
  the 
  film 
  ; 
  for 
  the 
  drop 
  

   spreads 
  before 
  the 
  radial 
  outgrowths 
  are 
  given 
  off 
  from 
  its 
  

   periphery, 
  and 
  an 
  upper 
  membrane 
  of 
  precipitate 
  can 
  be 
  

  

  