﻿136 
  E. 
  J. 
  ALr,KN. 
  

  

  preparations 
  stain 
  blue, 
  in 
  contrast 
  to 
  the 
  nucleolus 
  and 
  

   cliromatin 
  gi'anules, 
  whicli 
  stain 
  red. 
  It 
  disappears 
  as 
  the 
  

   eo-ff 
  continues 
  to 
  mature, 
  when 
  the 
  whole 
  of 
  the 
  protoplasmic 
  

  

  DO 
  ^ 
  

  

  contents 
  of 
  the 
  egg 
  becomes 
  crowded 
  with 
  yolk 
  granules, 
  

   which 
  stain 
  bine 
  in 
  the 
  preparations 
  (figs. 
  02, 
  Oo 
  and 
  64). 
  

  

  The 
  ripe 
  eggs 
  are 
  lenticular 
  in 
  shape, 
  the 
  long 
  diameter 
  

   being 
  about 
  double 
  the 
  short. 
  Around 
  the 
  line 
  of 
  greatest 
  

   circumference 
  there 
  is 
  a 
  single 
  I'ow 
  of 
  vesicles, 
  seen 
  clearly 
  in 
  

   the 
  optical 
  section 
  of 
  a 
  fresh 
  egg 
  represented 
  in 
  fig. 
  64. 
  

   These 
  vesicles 
  are 
  ])ear-shaped 
  and 
  o])eu 
  on 
  the 
  exterior 
  surface 
  

   of 
  the 
  egg 
  by 
  mesins 
  of 
  fine 
  tubes 
  passiug 
  through 
  the 
  thick 
  

   eo-g 
  membrane. 
  In 
  fresh 
  eggs 
  the 
  vesicles 
  look 
  more 
  clear 
  

   and 
  ti-ansi)arent 
  than 
  the 
  general 
  egg 
  substance; 
  in 
  sections 
  

   a 
  small, 
  shrunken 
  mass 
  of 
  slightly 
  staining 
  substance 
  appears 
  

   in 
  the 
  centre 
  of 
  each 
  (figs. 
  62 
  and 
  6'S). 
  The 
  function 
  of 
  

   these 
  vesicles 
  is 
  unknown, 
  though 
  their 
  appearance 
  suggests 
  

   that 
  they 
  may 
  contain 
  a 
  fluid 
  vrliich 
  is 
  at 
  some 
  stnge 
  secreted 
  

   on 
  to 
  the 
  surface 
  of 
  the 
  egg. 
  That 
  the 
  vesicles 
  are 
  intimately 
  

   connected 
  with 
  the 
  egg 
  membrane 
  is 
  shown 
  l)y 
  the 
  fact 
  that 
  

   when 
  the 
  protoplasmic 
  contents 
  of 
  the 
  egg 
  shrink, 
  as 
  they 
  do 
  

   when 
  the 
  egg 
  is 
  allowed 
  to 
  remain 
  soaking 
  for 
  some 
  time 
  in 
  

   sea 
  water, 
  the 
  vesicles 
  completely 
  retain 
  their 
  position 
  around 
  

   the 
  circumference 
  of 
  the 
  egg 
  membrane, 
  their 
  bases 
  being- 
  

   connected 
  by 
  threads 
  of 
  protoplasm 
  Avith 
  the 
  shrunken 
  mass 
  

   of 
  the 
  cell 
  contents. 
  This 
  is 
  shown 
  in 
  fig. 
  65, 
  drawn 
  from 
  a 
  

   fresh 
  egg 
  which 
  had 
  remained 
  for 
  some 
  hours 
  in 
  sea-water. 
  

  

  A^esicles 
  similar 
  to 
  those 
  just 
  referred 
  to 
  were 
  described 
  and 
  

   figured 
  by 
  Claparede 
  (1868) 
  in 
  Nerine 
  cirratulus, 
  in 
  which 
  

   form 
  one 
  circle 
  of 
  them 
  is 
  found 
  round 
  the 
  equator, 
  just 
  as 
  in 
  

   the 
  eggs 
  of 
  Poecilochaetus. 
  In 
  Nerine 
  auriseta, 
  on 
  the 
  

   other 
  hand, 
  Claparede 
  found 
  three 
  irregular 
  rows 
  of 
  similar 
  

   vesicles 
  ari'anged 
  round 
  the 
  greatest 
  circumference 
  of 
  the 
  

   elliptical 
  eggs. 
  In 
  neither 
  case, 
  however, 
  does 
  Claparede 
  

   describe 
  the 
  fine 
  tubes 
  which 
  place 
  the 
  vesicles 
  in 
  communica- 
  

   tion 
  with 
  the 
  exterior. 
  The 
  following 
  observation, 
  which 
  he 
  

   records 
  concerning 
  the 
  eggs 
  of 
  Nerine 
  auriseta, 
  is 
  of 
  

   interest: 
  — 
  " 
  L'action 
  d'une 
  faibles 
  solution 
  de 
  carminate 
  

  

  