﻿THE 
  ANATOMY 
  OF 
  1'(EC1L0CH.ETUS, 
  CLAPAEEDE. 
  109 
  

  

  mefchyl-blue-eosin 
  preparations, 
  the 
  long 
  rods 
  blue. 
  The 
  

   diameter 
  of 
  the 
  hitter 
  appears 
  to 
  be 
  somewhat 
  greater 
  than 
  

   the 
  diameter 
  of 
  the 
  hairs 
  where 
  thei'e 
  pass 
  through 
  the 
  

   cuticle. 
  

  

  In 
  the 
  horizontal 
  section 
  shoAvu 
  in 
  fig. 
  34, 
  at 
  a 
  level 
  

   immediately 
  inside 
  the 
  ends 
  of 
  the 
  long 
  rods, 
  three 
  large 
  oval 
  

   nuclei 
  {n. 
  h.) 
  are 
  seen, 
  and 
  in 
  neighbouring 
  sections 
  other 
  

   nuclei 
  appear 
  in 
  a 
  corresponding 
  position. 
  These 
  I 
  take 
  to 
  be 
  

   the 
  nuclei 
  of 
  the 
  hair-bearing 
  cells, 
  the 
  interpretation 
  being 
  

   based 
  on 
  their 
  similarity 
  in 
  situation 
  to 
  those 
  of 
  the 
  ciliated 
  

   cells 
  of 
  the 
  CESophagus 
  and 
  nuchal 
  organ 
  already 
  referred 
  to 
  

   (cf. 
  p. 
  114 
  and 
  p. 
  117). 
  The 
  possibility 
  must, 
  however, 
  be 
  

   borne 
  in 
  mind 
  that 
  these 
  nuclei 
  may 
  really 
  belong 
  to 
  the 
  

   posterior 
  row 
  of 
  muscle-bands, 
  and 
  their 
  position 
  in 
  fig. 
  34 
  

   lends 
  some 
  support 
  to 
  this 
  view. 
  In 
  this 
  case 
  they 
  would 
  

   resemble 
  the 
  nuclei 
  shown 
  in 
  fig. 
  35 
  lying 
  between 
  the 
  

   anterior 
  muscle-bands. 
  Should 
  further 
  investigation 
  show 
  

   this 
  to 
  be 
  the 
  case, 
  the 
  nuclei 
  of 
  the 
  hair-bearing 
  cells 
  must 
  be 
  

   sought 
  elsewhere. 
  

  

  GTanglion. 
  — 
  The 
  remaining 
  structure 
  to 
  be 
  described 
  in 
  

   connection 
  with 
  the 
  lateral 
  sense-organ 
  is 
  the 
  ganglion. 
  The 
  

   ganglion-cells 
  may 
  be 
  conveniently 
  divided 
  into 
  two 
  groups 
  — 
  

   a 
  group 
  of 
  large 
  cells, 
  which 
  occupy 
  the 
  anterior 
  dorsal 
  

   portion 
  of 
  the 
  organ, 
  in 
  front 
  of 
  and 
  above 
  the 
  hair-bearing 
  

   cells, 
  and 
  a 
  group 
  composed 
  of 
  a 
  large 
  number 
  of 
  small 
  cells, 
  

   which 
  constitute 
  the 
  posterior 
  portion 
  of 
  the 
  organ. 
  

  

  The 
  large 
  ganglion-celis 
  are 
  represented 
  in 
  figs. 
  36 
  and 
  37 
  

   (transverse 
  sections). 
  They 
  are 
  large, 
  uni-polar 
  cells, 
  with 
  

   their 
  processes 
  generally 
  directed 
  towards 
  the 
  cuticle. 
  

   Whether 
  these 
  processes 
  eventually 
  reach 
  the 
  cuticle 
  or 
  

   whether 
  they 
  come 
  into 
  contact 
  with 
  the 
  hair-bearing 
  cells 
  I 
  

   have 
  been 
  unable 
  to 
  determine 
  with 
  certainty. 
  The 
  nuclei 
  of 
  

   these 
  ganglion-cells 
  are 
  very 
  large, 
  and 
  either 
  spherical 
  or 
  

   oval 
  in 
  shape. 
  The 
  contents 
  of 
  the 
  cell-bodies 
  stain 
  deeply. 
  

  

  The 
  suiall 
  ganglion-cells 
  (fig-. 
  34, 
  g. 
  I. 
  o.) 
  do 
  not 
  for 
  the 
  

   most 
  part 
  show 
  definite 
  cell-outlines 
  in 
  the 
  preparations, 
  but 
  

   appear 
  rather 
  as 
  a 
  mass 
  of 
  more 
  or 
  less 
  closely 
  packed 
  nuclei, 
  

  

  