﻿THE 
  ANATOiMY 
  OF 
  l'G<]GI 
  LO0H7[<7rUS, 
  CLAPAKEDK. 
  125 
  

  

  Bainls 
  of 
  ol^Iiqiie 
  muscles 
  run 
  from 
  the 
  outer 
  dorsal 
  edge 
  of 
  

   the 
  ventral 
  uerve-cord 
  on 
  each 
  side^ 
  pass 
  over 
  the 
  longitu- 
  

   dinal 
  ventral 
  muscle-bands, 
  and 
  are 
  inserted 
  in 
  the 
  lateral 
  

   walls 
  of 
  th(> 
  body 
  between 
  the 
  parapodia. 
  

  

  External 
  Muscles 
  of 
  the 
  Lateral 
  Organs 
  and 
  

   Muscles 
  of 
  the 
  Cha3tal 
  Sacs. 
  — 
  Four 
  large 
  bands 
  of 
  

   muscle 
  are 
  inserted 
  at 
  the 
  apex 
  of 
  each 
  lateral 
  organ 
  (PI, 
  10, 
  

   figs. 
  34 
  and 
  37, 
  muse), 
  viz. 
  (1) 
  a 
  band 
  which 
  runs 
  down- 
  

   Avards 
  and 
  inwards 
  to 
  the 
  inner 
  end 
  of 
  the 
  neuropodial 
  

   chi^etal 
  sac, 
  which 
  is 
  clearly 
  one 
  of 
  the 
  tw^o 
  bands 
  used 
  to 
  

   protrude 
  the 
  chasta^ 
  ; 
  (2) 
  a 
  similar 
  band 
  running 
  upwards 
  

   and 
  inwards 
  to 
  the 
  base 
  of 
  the 
  notopodial 
  cha3tal 
  sac; 
  (o) 
  a 
  

   broad 
  band 
  of 
  muscle 
  which 
  runs 
  from 
  the 
  lateral 
  organ 
  

   downwards, 
  passes 
  behind 
  the 
  chastal 
  sac 
  and 
  is 
  inserted 
  in 
  

   the 
  ventral 
  body-wall 
  below 
  the 
  base 
  of 
  the 
  neuropodial 
  

   cirrus, 
  and 
  (4) 
  a 
  similar 
  band 
  running 
  upwards 
  and 
  inserted 
  

   in 
  the 
  dorsal 
  body-wall 
  above 
  the 
  base 
  of 
  the 
  notopodial 
  

   cirrus. 
  Lying 
  in 
  contact 
  with 
  the 
  muscle-fibres 
  of 
  bands 
  3 
  

   and 
  4 
  are 
  a 
  number 
  of 
  fibres, 
  which 
  run 
  direct 
  from 
  the 
  

   dorsal 
  to 
  the 
  ventral 
  body-wall. 
  These 
  pass 
  close 
  to 
  the 
  apex 
  

   of 
  the 
  lateral 
  organ, 
  to 
  which 
  they 
  are 
  joined 
  by 
  connective 
  

   tissue, 
  but 
  they 
  have 
  no 
  free 
  ends 
  inserted 
  in 
  that 
  apex. 
  

  

  In 
  addition 
  to 
  the 
  muscle-bands 
  described 
  above, 
  (1) 
  and 
  

   (2), 
  running 
  from 
  the 
  apex 
  of 
  the 
  lateral 
  organs 
  to 
  the 
  

   inner 
  ends 
  of 
  the 
  two 
  cLtetal 
  sacs, 
  a 
  second 
  band 
  runs 
  from 
  

   the 
  inner 
  end 
  of 
  each 
  sac, 
  passes 
  in 
  the 
  one 
  case 
  downwards 
  

   and 
  outwards 
  and 
  in 
  the 
  other 
  upwards 
  and 
  outwards 
  and 
  is 
  

   inserted 
  in 
  the 
  body-wall. 
  Thus 
  each 
  sac 
  has 
  two 
  strong 
  

   muscles 
  from 
  its 
  apex 
  to 
  the 
  body-wall, 
  one 
  above 
  and 
  one 
  

   below, 
  by 
  the 
  contraction 
  of 
  which 
  it 
  and 
  its 
  chsetie 
  are 
  

   protruded. 
  

  

  Blood 
  System. 
  

  

  The 
  anatomy 
  of 
  the 
  vascular 
  system 
  constitutes 
  one 
  of 
  

   the 
  most 
  striking 
  and 
  interesting 
  features 
  of 
  Poecilo- 
  

   cluetus. 
  The 
  bright 
  scarlet 
  of 
  the 
  blood 
  gives 
  to 
  the 
  

   anterior 
  portion 
  of 
  the 
  body 
  its 
  characteristic 
  coloui-, 
  and 
  the 
  

  

  