﻿152 
  Prof. 
  M'lntosh's 
  Notes 
  from 
  the 
  

  

  various 
  cracks 
  and 
  crevices 
  of 
  the 
  rocks 
  in 
  the 
  same 
  region. 
  

   The 
  head 
  (prostomium) 
  is 
  conical, 
  and 
  on 
  each 
  side, 
  a 
  short 
  

   distance 
  from 
  the 
  tip, 
  an 
  oblique 
  depression 
  slopes 
  outward 
  

   and 
  backward, 
  and 
  from 
  the 
  point 
  at 
  which 
  these 
  converging 
  

   grooves 
  meet 
  a 
  ridge 
  runs 
  forward 
  to 
  the 
  tip 
  of 
  the 
  snout. 
  

   Ventrally 
  a 
  deep 
  groove 
  leads 
  backward 
  to 
  the 
  mouth, 
  which 
  

   is 
  bounded 
  posteriorly 
  by 
  a 
  thick 
  transverse 
  lip. 
  In 
  some 
  

   specimens 
  from 
  Lochmaddy 
  a 
  little 
  pigment 
  occurs 
  on 
  the 
  

   snout 
  at 
  the 
  posterior 
  and 
  outer 
  angle 
  of 
  the 
  triangular 
  

   anterior 
  region, 
  thus 
  simulating 
  eyes 
  — 
  indeed, 
  the 
  pigment 
  

   is 
  occasionally 
  symmetrically 
  arranged. 
  In 
  others 
  from 
  

   Guernsey 
  and 
  Herm 
  a 
  distinct 
  band 
  of 
  ocular 
  points 
  passes 
  

   from 
  one 
  side 
  of 
  the 
  base 
  of 
  the 
  snout 
  to 
  the 
  other 
  just 
  in 
  

   front 
  of 
  the 
  constriction 
  indicating 
  the 
  region. 
  A 
  variety 
  

   with 
  a 
  blackish 
  snout 
  is 
  met 
  with 
  at 
  Herm, 
  and 
  Dr. 
  Sowerby 
  

   forwarded 
  some 
  in 
  a 
  similar 
  condition 
  from 
  the 
  estuary 
  of 
  

   the 
  Orwell 
  near 
  Ipswich. 
  

  

  The 
  body 
  is 
  from 
  6 
  to 
  9 
  inches 
  in 
  length, 
  rounded 
  on 
  the 
  

   dorsum, 
  flattened 
  ventrally, 
  tapered 
  anteriorly 
  and 
  more 
  

   distinctly 
  but 
  gradually 
  diminished 
  posteriorly, 
  where 
  it 
  ends 
  

   in 
  a 
  pointed 
  tail, 
  the 
  slit-like 
  anus 
  being 
  dorsal, 
  whilst 
  in 
  the 
  

   mid-ventral 
  line 
  in 
  some 
  specimens 
  is 
  a 
  small 
  process 
  like 
  a 
  

   rudimentary 
  cirrus. 
  Others 
  show 
  in 
  lateralsview 
  a 
  process 
  

   above 
  and 
  a 
  little 
  in 
  front 
  of 
  that 
  just 
  mentioned, 
  and 
  some 
  

   present 
  only 
  a 
  large 
  terminal 
  anus 
  with 
  a 
  rim 
  and 
  no 
  process. 
  

   Such 
  variations 
  probably 
  indicate 
  injuries 
  and 
  reproduction. 
  

   The 
  number 
  of 
  segments 
  ranges 
  to 
  300 
  and 
  upward 
  in 
  a 
  large 
  

   example. 
  Vertical 
  lines 
  of 
  dark 
  pigment 
  occur 
  in 
  the 
  sulci 
  

   at 
  the 
  segment-junctions 
  — 
  from 
  the 
  fourth 
  segment 
  back- 
  

   ward 
  for 
  some 
  distance. 
  

  

  On 
  an 
  elevated 
  ridge 
  which 
  lies 
  dorsally 
  between 
  the 
  fifth 
  

   and 
  sixth 
  bristled 
  segments 
  is 
  a 
  dense 
  mass 
  of 
  tentacles 
  on 
  

   each 
  side. 
  The 
  ridge 
  is 
  somewhat 
  crescentic 
  in 
  front, 
  

   straight 
  behind, 
  and 
  the 
  tentacles 
  in 
  the 
  cluster 
  number 
  at 
  

   least 
  twenty. 
  Each 
  segment 
  behind 
  the 
  foregoing 
  has 
  on 
  

   each 
  side 
  its 
  branchia 
  situated 
  behind 
  and 
  rather 
  above 
  the 
  

   level 
  of 
  the 
  upper 
  bristle-tuft, 
  and 
  this 
  throughout 
  the 
  whole 
  

   anterior 
  region, 
  to 
  the 
  number 
  of 
  about 
  one 
  hundred 
  in 
  

   large 
  examples. 
  The 
  branchiae 
  are 
  more 
  scattered 
  in 
  the 
  

   middle 
  and 
  posterior 
  regions, 
  and 
  cease 
  altogether 
  about 
  the 
  

   thirty-fifth 
  or 
  fortieth 
  segment 
  from 
  the 
  tip 
  of 
  the 
  tail. 
  

   After 
  the 
  seventh 
  or 
  eighth 
  the 
  bristled 
  segments 
  for 
  a 
  con- 
  

   siderable 
  distance 
  are 
  narrow, 
  then 
  become 
  slightly 
  wider, 
  

   and 
  again 
  toward 
  the 
  tip 
  of 
  the 
  tail 
  are 
  narrow. 
  The 
  

   remarkable 
  spiral 
  coils 
  of 
  the 
  branchiae 
  constitute 
  a 
  feature 
  

   of 
  the 
  species, 
  and 
  contact 
  with 
  sea- 
  water 
  is 
  apparently 
  less 
  

  

  