﻿118 
  E. 
  J. 
  ALLEN. 
  

  

  becomes 
  granular, 
  many 
  of 
  the 
  granules 
  being 
  of 
  a 
  character- 
  

   istic 
  yellowisb-brown 
  colour. 
  The 
  cilia 
  cannot 
  be 
  traced 
  as 
  

   far 
  as 
  the 
  nuclei 
  of 
  the 
  cells. 
  In 
  sections 
  of 
  material 
  fixed 
  in 
  

   Hermann's 
  fluid 
  and 
  stained 
  with 
  a 
  mixture 
  of 
  methyl-blue- 
  

   eosin 
  (fig. 
  44), 
  the 
  cuticle 
  stains 
  deep 
  blue, 
  the 
  cilia 
  faintly 
  

   blue, 
  the 
  layer 
  of 
  short 
  rods 
  bright 
  red, 
  the 
  cell 
  protoplasm 
  

   bluish, 
  whilst 
  the 
  nuclei 
  are 
  clear, 
  with 
  chromatin 
  granules 
  

   and 
  network 
  stained 
  deep 
  red. 
  

  

  The 
  structure 
  of 
  the 
  ciliated 
  cells 
  above 
  described, 
  as 
  well 
  

   as 
  those 
  of 
  the 
  nuchal 
  groove 
  (p. 
  114) 
  and 
  the 
  hair-bearing 
  

   cells 
  of 
  the 
  lateral 
  sense-organs 
  (p. 
  108), 
  agrees 
  with 
  that 
  found 
  

   by 
  Engelmann 
  (1880) 
  in 
  the 
  ciliated 
  cells 
  from 
  the 
  intestine 
  

   and 
  gills 
  of 
  Cyclas 
  cornea 
  and 
  Anodonta, 
  and 
  in 
  the 
  

   ciliated 
  cells 
  from 
  the 
  nose 
  of 
  the 
  frog. 
  Engelmann 
  clearly 
  

   describes 
  the 
  short 
  rods 
  under 
  the 
  name 
  of 
  "Fussstiicke," 
  

   and 
  also 
  the 
  internal 
  prolongations 
  of 
  the 
  cilia 
  within 
  the 
  

   cells, 
  which 
  he 
  was, 
  however, 
  able 
  to 
  trace 
  much 
  further 
  into 
  

   the 
  body 
  of 
  the 
  cell 
  than 
  I 
  have 
  succeeded 
  in 
  doing. 
  He 
  also 
  

   found 
  between 
  the 
  short 
  rods 
  and 
  the 
  cilia 
  proper 
  a 
  certain 
  

   differentiation 
  of 
  the 
  substance 
  of 
  the 
  bases 
  of 
  the 
  cilia, 
  which 
  

   he 
  calls 
  the 
  "bulbus." 
  These 
  "bulbi" 
  would 
  appear 
  to 
  cor- 
  

   respond 
  to 
  the 
  secondaiy 
  layer 
  of 
  short 
  rods 
  described 
  in 
  the 
  

   present 
  paper 
  at 
  the 
  bases 
  of 
  the 
  sensory 
  hairs 
  of 
  the 
  lateral 
  

   sense-organs 
  (p. 
  108, 
  PL 
  10, 
  figs. 
  34, 
  36, 
  39). 
  

  

  Englemann 
  states 
  that 
  Eimer 
  was 
  the 
  first 
  to 
  describe 
  

   correctly 
  the 
  relations 
  of 
  the 
  short 
  rods 
  (Fussstiicke) 
  to 
  the 
  

   cilia, 
  and 
  he 
  gives 
  several 
  other 
  references 
  to 
  previous 
  papers 
  

   dealing 
  with 
  the 
  subject. 
  

  

  More 
  recently 
  Greenwood 
  (1892) 
  has 
  shown 
  a 
  very 
  similar 
  

   structure 
  in 
  the 
  ciliated 
  cells 
  of 
  the 
  intestine 
  of 
  Lumbricus, 
  

   though 
  in 
  the 
  latter 
  worm, 
  to 
  judge 
  by 
  the 
  figures, 
  the 
  layer 
  

   of 
  short, 
  deeply 
  staining 
  rods 
  is 
  less 
  marked. 
  Greenwood, 
  

   however, 
  states 
  (p. 
  246) 
  " 
  the 
  cilia 
  occasionally 
  bear 
  tiny 
  

   varicosities 
  before 
  they 
  pass 
  into 
  the 
  body 
  of 
  the 
  cell. 
  

   Under 
  a 
  sufiiciently 
  high 
  power 
  these 
  are 
  distinguishable 
  as 
  

   belonging 
  each 
  to 
  a 
  ciliary 
  thread, 
  and 
  they 
  recall 
  Heiden- 
  

   hain's 
  description 
  of 
  similar 
  thickenings, 
  which 
  may 
  be 
  seen 
  

  

  