﻿102 
  Prof. 
  M'liitosh's 
  Notes 
  from 
  the 
  

  

  From 
  the 
  dorsal 
  surface 
  of 
  the 
  third 
  segment 
  eight 
  some- 
  

   what 
  stiff 
  branchiae 
  project 
  forward. 
  Tliey 
  are 
  proportionally 
  

   larger 
  than 
  in 
  Sabellidcs 
  borealls 
  and 
  more 
  finely 
  tapered. 
  

  

  The 
  hody 
  is 
  small 
  and 
  slender, 
  a 
  little 
  more 
  than 
  hali: 
  an 
  

   inch 
  in 
  length, 
  scarcely 
  tapered 
  anteriorly, 
  with 
  the 
  excep- 
  

   tion 
  of 
  the 
  short 
  cone 
  of 
  the 
  snout, 
  and 
  very 
  gently 
  tapered 
  

   posteriori)' 
  till 
  near 
  the 
  tip, 
  when 
  more 
  rapid 
  diminution 
  

   occurs 
  to 
  the 
  vent, 
  on 
  each 
  side 
  of 
  which 
  is 
  a 
  slender 
  cirrus. 
  

  

  So 
  far 
  as 
  can 
  be 
  observed, 
  fourteen 
  bristled 
  segments 
  

   occur 
  anteriorly, 
  distinguished 
  by 
  the 
  absence 
  of 
  the 
  long 
  

   cirrus 
  which 
  occurs 
  in 
  the 
  sixteen 
  posterior 
  segments. 
  

   The 
  bristles 
  are 
  short 
  and 
  translucent, 
  with 
  slightly 
  curved, 
  

   winged_, 
  and 
  tapering 
  tips, 
  and 
  they 
  are 
  borne 
  on 
  a 
  prominent 
  

   setii;erous 
  process. 
  

  

  The 
  anterior 
  hooks 
  have 
  a 
  rounded 
  crown, 
  the 
  curve 
  

   smoothly 
  running 
  into 
  the 
  convex 
  dorsal 
  (or 
  posterior) 
  

   outline, 
  and 
  the 
  four 
  teeth 
  are 
  characteristic, 
  that 
  next 
  the 
  

   crown 
  being 
  the 
  largest 
  and 
  the 
  second, 
  third, 
  and 
  fourth 
  

   regularly 
  diminishing. 
  The 
  prow 
  curves 
  rather 
  far 
  forward 
  

   and 
  the 
  tip 
  is 
  somewhat 
  small. 
  

  

  The 
  posterior 
  hooks 
  are 
  prominently 
  situated 
  on 
  the 
  edge 
  

   of 
  the 
  filiet, 
  and 
  are 
  fi'ee 
  distally, 
  a 
  space 
  se})arating 
  the 
  

   one 
  from 
  the 
  other. 
  They 
  are 
  very 
  minute, 
  and 
  differ 
  from 
  

   the 
  antei'ior 
  in 
  the 
  sinuous 
  curve 
  of 
  the 
  crown 
  and 
  the 
  

   slightly 
  broader 
  prow. 
  They 
  have, 
  however, 
  only 
  four 
  teeth, 
  

   as 
  m 
  front. 
  The 
  hooks 
  in 
  the 
  var. 
  med'iterranea, 
  of 
  De 
  St. 
  

   Joseph, 
  unfortuTiatcly, 
  are 
  so 
  indistinct 
  in 
  the 
  figure 
  that 
  

   little 
  can 
  be 
  said 
  about 
  them, 
  except 
  that 
  they 
  have 
  four 
  

   teeth 
  in 
  lateral 
  view, 
  a 
  single 
  row 
  occurring 
  in 
  the 
  thoracic 
  

   forms 
  and 
  a 
  treble 
  row 
  in 
  the 
  abdominal. 
  

  

  The 
  tube 
  is 
  a 
  slender 
  one 
  to 
  suit 
  the 
  small 
  size 
  of 
  the 
  

   species, 
  and 
  coated 
  with 
  mud 
  and 
  lined 
  by 
  secretion. 
  

  

  The 
  fourth 
  form 
  is 
  Samytha 
  sexcirrata, 
  Sars, 
  chiefly 
  from 
  

   Zetlandic 
  waters. 
  In 
  this 
  the 
  head 
  (prostomium) 
  forms 
  a 
  

   somewhat 
  broad 
  anterior 
  central 
  process 
  with 
  a 
  peristomial 
  

   buttress 
  on 
  each 
  side. 
  Beneath 
  is 
  the 
  flap 
  bearing 
  ventrally 
  

   the 
  buccal 
  tentacles, 
  which 
  are 
  smooth 
  and 
  somewhat 
  

   enlarged 
  distally. 
  The 
  posterior 
  lip 
  is 
  prominent, 
  and 
  passes 
  

   upward 
  at 
  each 
  side 
  as 
  a 
  process 
  separated 
  from 
  the 
  cephalic 
  

   border 
  by 
  a 
  notch. 
  When 
  viewed 
  laterally, 
  it 
  Ibrms 
  a 
  pro- 
  

   jecting 
  spout-shaped 
  frill. 
  The 
  segment 
  behind 
  the 
  buccal 
  

   has 
  no 
  processes. 
  The 
  third 
  and 
  fourth 
  segments 
  carry 
  

   dorsally 
  the 
  branchiae, 
  which 
  are 
  three 
  on 
  each 
  side 
  and 
  

   comparatively 
  long 
  tapering 
  (subulate) 
  organs. 
  In 
  the 
  

  

  