﻿THE 
  ANATOMY 
  OF 
  FWOIWGIIMTVS, 
  CLAPAE^DE. 
  137 
  

  

  d'ammoniaque 
  les 
  modifie 
  d'une 
  mauiere 
  remarqaable. 
  Elles 
  

   se 
  coloreut 
  assez 
  rapideincut 
  en 
  rouge 
  intense, 
  tandis 
  que 
  le 
  

   vitellus 
  ne 
  se 
  teint 
  qu'en 
  rouge 
  pale, 
  et 
  que 
  le 
  chorion 
  reste 
  

   parfaitenient 
  incolore." 
  This 
  observation 
  appears 
  to 
  me 
  to 
  

   agree 
  better 
  with 
  the 
  suggestion 
  made 
  above 
  that 
  the 
  vesicles 
  

   may 
  contain 
  a 
  secretory 
  product 
  than 
  with 
  the 
  view 
  set 
  forth 
  

   by 
  Claparede 
  : 
  — 
  '' 
  Je 
  ne 
  puis 
  m'empecher 
  de 
  supposer 
  que 
  

   ces 
  vesicules 
  (ou 
  peut-etre 
  mieux 
  ces 
  spheres 
  protoplasmiques) 
  

   jouent 
  un 
  role 
  important 
  dans 
  la 
  formation 
  du 
  blastoderme 
  '^ 
  

   (Claparede, 
  1868, 
  p. 
  333). 
  

  

  The 
  egg 
  membrane 
  of 
  the 
  ripe 
  egg 
  of 
  Poecilochoetus 
  is 
  

   very 
  thick 
  and 
  stains 
  deeply 
  (blue 
  in 
  methyl- 
  blue-eosin 
  prepara- 
  

   tions). 
  Its 
  surface 
  is 
  ornamented 
  by 
  raised 
  lines, 
  which 
  form 
  

   an 
  irregular 
  pattern 
  upon 
  it 
  (fig. 
  66, 
  from 
  a 
  fresh 
  egg). 
  These 
  

   lines 
  or 
  ridges 
  are 
  clearly 
  visible 
  in 
  sections 
  (figs. 
  62 
  and 
  63). 
  

  

  The 
  germinal 
  vesicle 
  is 
  large, 
  its 
  diameter 
  being 
  little 
  less 
  

   than 
  the 
  smaller 
  diameter 
  of 
  the 
  egg. 
  It 
  contains 
  one 
  large 
  

   nucleolus, 
  which 
  is 
  composed 
  of 
  a 
  larger 
  and 
  a 
  smaller 
  

   spherical 
  portion 
  (cf. 
  fig. 
  64, 
  from 
  a 
  fresh 
  egg, 
  and 
  fig. 
  63, 
  

   from 
  a 
  section). 
  Fig. 
  62 
  shows 
  a 
  condition 
  of 
  the 
  nucleolus 
  

   which 
  is 
  very 
  often 
  seen 
  in 
  preserved 
  material. 
  It 
  here 
  con- 
  

   sists 
  of 
  a 
  very 
  deeply 
  staining 
  portion, 
  which 
  takes 
  the 
  form 
  

   of 
  a 
  cap 
  resting 
  upon 
  a 
  more 
  or 
  less 
  spherical, 
  transparent 
  

   vacuole. 
  Such 
  a 
  form 
  of 
  the 
  nucleolus 
  is 
  not 
  uncommon 
  in 
  

   the 
  eggs 
  of 
  other 
  animals 
  (for 
  literature 
  see 
  Korschelt 
  and 
  

   Heider, 
  1902). 
  When 
  the 
  nucleolus 
  is 
  in 
  the 
  state 
  just 
  

   described, 
  a 
  number 
  of 
  other 
  deeply 
  staining 
  granules 
  are 
  

   present 
  in 
  the 
  germinal 
  vesicle. 
  

  

  Nothing 
  has 
  been 
  ascertained 
  as 
  to 
  the 
  history 
  of 
  the 
  eggs 
  

   after 
  they 
  leave 
  the 
  body 
  of 
  the 
  worm. 
  

  

  The 
  Spermatozoa. 
  — 
  The 
  place 
  of 
  origin 
  of 
  the 
  male 
  

   germinal 
  cells 
  is 
  less 
  restricted 
  than 
  that 
  of 
  the 
  female. 
  

   They 
  sometimes 
  arise, 
  like 
  the 
  ova, 
  from 
  the 
  ccelomic 
  epithe- 
  

   lium 
  which 
  surrounds 
  the 
  nephridial 
  tube, 
  but 
  may 
  also 
  be 
  

   derived 
  from 
  ccelomic 
  epithelium 
  in 
  other 
  parts 
  of 
  the 
  

   segment, 
  more 
  especially 
  from 
  that 
  of 
  the 
  anterior 
  septum. 
  

   In 
  ripe 
  males 
  the 
  body-cavity 
  in 
  the 
  genital 
  segments 
  is 
  filled 
  

  

  VOL. 
  48, 
  PART 
  1. 
  NEW 
  SERIES. 
  10 
  

  

  