﻿392 
  JOHN 
  RENNIE. 
  

  

  granular 
  or 
  fibrillate^ 
  the 
  nuclei 
  with 
  distinct 
  nucleolus 
  and 
  

   chromatin 
  network. 
  Distinctively 
  dark 
  and 
  light 
  areas 
  

   were 
  not 
  observed. 
  

  

  Zoarces 
  viviparus. 
  — 
  As 
  may 
  be 
  seen 
  from 
  fig. 
  11, 
  the 
  

   relation 
  between 
  pancreas 
  and 
  principal 
  islet 
  is 
  extremely 
  

   slight. 
  This 
  is 
  one 
  of 
  the 
  cases 
  where, 
  were 
  it 
  not 
  from 
  the 
  

   known 
  relations 
  as 
  revealed 
  in 
  other 
  species, 
  it 
  would 
  be 
  

   difficult 
  to 
  relate 
  the 
  body 
  to 
  its 
  proper 
  category. 
  It 
  is 
  

   surrounded 
  by 
  a 
  fairly 
  thick 
  capsule, 
  upon 
  which 
  there 
  is 
  a 
  

   deposition 
  of 
  pigment. 
  I 
  sectioned 
  one 
  throughout 
  its 
  whole 
  

   length, 
  and 
  found 
  that 
  it 
  was 
  penetrated 
  by 
  no 
  large 
  blood- 
  

   vessels, 
  though 
  capillaries 
  were 
  abundant. 
  The 
  greater 
  part 
  

   of 
  the 
  space 
  within 
  the 
  capsule 
  is 
  occupied 
  by 
  bands 
  of 
  

   darkly 
  staining 
  cells. 
  The 
  parts 
  between 
  these 
  bauds, 
  which 
  

   wind 
  irregularly, 
  are 
  occupied 
  by 
  cells 
  which 
  stain 
  lightly 
  

   and 
  ai*e 
  of 
  different 
  form 
  from 
  the 
  others. 
  The 
  columns 
  of 
  

   darkly 
  staining 
  cells 
  are 
  more 
  richly 
  supplied 
  with 
  capillaries 
  

   than 
  are 
  the 
  cells 
  occupying 
  the 
  spaces 
  between. 
  The 
  

   former 
  are 
  narrow, 
  cylindrical, 
  or 
  fusiform, 
  with 
  very 
  finely 
  

   granular 
  contents, 
  and 
  measure 
  about 
  10 
  /j. 
  across 
  the 
  narrow 
  

   diameter. 
  The 
  nucleus 
  is 
  oval, 
  and 
  stains 
  very 
  darkly, 
  

   being 
  filled 
  with 
  numerous 
  minute 
  chromatin 
  granules. 
  It 
  

   frequently 
  almost 
  fills 
  the 
  width 
  of 
  the 
  cell, 
  and 
  is 
  about 
  9 
  fx. 
  

   The 
  cells 
  of 
  the 
  lightly 
  staining 
  areas 
  are 
  irregularly 
  poly- 
  

   hedral 
  in 
  form, 
  their 
  cytoplasm 
  shows 
  a 
  network 
  of 
  fibrils 
  

   rather 
  than 
  granules, 
  while 
  the 
  nucleus 
  has 
  an 
  irregular 
  

   outline 
  and 
  contains 
  fewer 
  chromatin 
  granules 
  than 
  that 
  of 
  

   the 
  darkly 
  staining 
  form 
  (fig. 
  12). 
  

  

  Ammodytes 
  tobianus. 
  — 
  Besides 
  small 
  islets, 
  two 
  fairly 
  

   large 
  examples 
  of 
  irregular 
  outline 
  were 
  found 
  in 
  this 
  species. 
  

   They 
  were 
  all 
  completely 
  enveloped 
  in 
  pancreatic 
  tissue, 
  and 
  

   did 
  not 
  possess 
  a 
  limiting 
  capsule. 
  The 
  capillaries 
  were 
  

   very 
  abundant, 
  so 
  much 
  so 
  that 
  in 
  mauy 
  parts 
  they 
  were 
  

   separated 
  from 
  each 
  other 
  by 
  the 
  width 
  of 
  only 
  a 
  single 
  cell. 
  

   In 
  consequence 
  of 
  this 
  arrangement 
  the 
  cells 
  appeared 
  in 
  

   columns 
  in 
  certain 
  parts, 
  they 
  stained 
  more 
  darkly 
  than 
  the 
  

   rest 
  of 
  the 
  islet, 
  and 
  were 
  of 
  different 
  form 
  (fig. 
  6). 
  The 
  

  

  