﻿186 
  On 
  the 
  Anatomy 
  of 
  the 
  Connective 
  Tissues. 
  [Jan. 
  21, 
  

  

  double 
  layer 
  of 
  quadrangular 
  and 
  hexagonal 
  cells, 
  identical 
  in 
  general 
  

   appearance 
  with 
  an 
  epithelium. 
  Between 
  the 
  two 
  layers 
  there 
  is 
  a 
  thin 
  

   transparent 
  medium. 
  

  

  7. 
  From 
  the 
  neurilemma 
  of 
  the 
  sciatic 
  nerve 
  of 
  the 
  frog, 
  when 
  cut 
  in 
  

   narrow 
  longitudinal 
  strips, 
  after 
  a 
  few 
  hours, 
  branched 
  cells 
  of 
  different 
  

   types 
  of 
  form 
  are 
  seen 
  isolated 
  in 
  the 
  fluid 
  near 
  the 
  cut 
  edges. 
  These 
  

   cells 
  are 
  of 
  two 
  well-marked 
  general 
  types. 
  In 
  one 
  a 
  small 
  smooth- 
  

   contoured 
  elongated 
  mass 
  of 
  protoplasma 
  is 
  continuous 
  at 
  both 
  ends 
  with 
  

   a 
  fine 
  long 
  thread-like 
  fibre 
  ; 
  in 
  another 
  an 
  irregularly 
  contoured, 
  but 
  

   generally 
  somewhat 
  elongated, 
  mass 
  gives 
  off 
  numerous 
  sharply 
  denned, 
  

   very 
  fine 
  glistening 
  fibres 
  in 
  all 
  directions. 
  Sometimes 
  a 
  protoplasmic 
  

   centre 
  terminates 
  at 
  one 
  end 
  by 
  a 
  single 
  fibre, 
  and 
  by 
  two 
  at 
  the 
  other. 
  

   These 
  fibres 
  are 
  often 
  of 
  great 
  length, 
  and 
  the 
  protoplasmic 
  mass 
  can 
  

   sometimes 
  only 
  be 
  found 
  by 
  carefully 
  tracing 
  them 
  whilst 
  moving 
  the 
  

   object-glass. 
  

  

  8. 
  Fibrillary 
  tissue 
  is 
  seen 
  to 
  be 
  composed 
  of 
  imiform 
  flat, 
  ribbon-like 
  

   bands, 
  whose 
  breadth 
  approaches 
  the 
  diameter 
  of 
  a 
  human 
  red 
  blood- 
  

   corpuscle. 
  These 
  are 
  seen 
  in 
  their 
  simplest 
  form 
  when 
  extruded 
  from 
  the 
  

   neurilemma 
  of 
  the 
  sciatic 
  nerve 
  of 
  the 
  frog, 
  which 
  takes 
  place 
  within 
  

   24 
  hours' 
  maceration. 
  From 
  their 
  position 
  in 
  this 
  membrane 
  they 
  form 
  

   part 
  of 
  the 
  transparent 
  medium 
  which 
  exists 
  between 
  the 
  two 
  layers 
  of 
  

   quadrangular 
  cells. 
  They 
  are 
  mostly 
  marked 
  by 
  a 
  puckered 
  appearance 
  

   transversely. 
  

  

  In 
  skin 
  and 
  tendon, 
  after 
  a 
  few 
  days' 
  maceration 
  in 
  the 
  sealed 
  fluid, 
  

   the 
  fibrillary 
  tissue 
  is 
  seen 
  to 
  be 
  composed 
  of 
  extremely 
  fine 
  but 
  sharply 
  

   contoured 
  fibrillae, 
  arranged 
  in 
  parallel 
  bands, 
  which 
  are 
  of 
  the 
  same 
  

   breadth 
  as 
  the 
  soft 
  ribbon-like 
  bands 
  which 
  are 
  isolable 
  from 
  the 
  neuri- 
  

   lemma. 
  

  

  The 
  respective 
  appearances 
  in 
  the 
  neurilemma 
  and 
  in 
  tendon 
  indicate 
  

   extremes 
  in 
  the 
  condition 
  of 
  this 
  tissue, 
  and 
  represent, 
  according 
  to 
  the 
  

   author, 
  primary 
  bundles 
  of 
  connective 
  tissue. 
  

  

  9. 
  The 
  primary 
  bundles 
  of 
  the 
  cornea 
  are 
  seen 
  only 
  exceptionally 
  by 
  

   this 
  method, 
  but 
  can 
  be 
  demonstrated 
  with 
  great 
  precision 
  by 
  sealing 
  up 
  

   a 
  frog's 
  cornea 
  in 
  a 
  mixture 
  of 
  equal 
  parts 
  of 
  half-per-cent. 
  solution 
  of 
  

   chloride 
  of 
  gold 
  and 
  concentrated 
  acetic 
  acid. 
  

  

  10. 
  In 
  nerve-bundles, 
  after 
  24 
  hours' 
  maceration 
  in 
  aqueous 
  humour, 
  

   some 
  of 
  the 
  medullated 
  fibres 
  may 
  be 
  seen 
  to 
  have 
  their 
  contour 
  broken 
  

   transversely 
  by 
  straight 
  hyaline 
  spaces. 
  The 
  author 
  assigns 
  this 
  appear- 
  

   ance 
  to 
  the 
  peculiarity 
  of 
  structure 
  described 
  by 
  Eanvier. 
  

  

  11. 
  The 
  breadth 
  and 
  appearance 
  of 
  the 
  rods 
  of 
  the 
  frog's 
  retina 
  are 
  

   nearly 
  identical 
  with 
  those 
  of 
  the 
  primary 
  bundles 
  of 
  the 
  neurilemma. 
  

  

  The 
  transverse 
  markings 
  described 
  by 
  Max 
  Schultze 
  as 
  being 
  produced 
  

   by 
  the 
  action 
  of 
  osmic 
  acid 
  on 
  the 
  rods 
  and 
  cones, 
  resemble 
  the 
  transverse 
  

   puckerings 
  in 
  the 
  primary 
  bundles. 
  In 
  both 
  rods 
  and 
  primary 
  bundles, 
  

   after 
  prolonged 
  maceration 
  in 
  aqueous 
  humour, 
  the 
  free 
  ends 
  of 
  each 
  indi- 
  

  

  