﻿154 
  Prof, 
  Mcintosh's 
  Notes 
  from 
  the 
  

  

  arise 
  less 
  definitely 
  than 
  in 
  C. 
  tentaculatus, 
  it 
  being 
  difficult 
  

   to 
  say 
  whether 
  they 
  are 
  mainly 
  opposite 
  the 
  sixth 
  or 
  the 
  

   seventh 
  bristles, 
  -whereas 
  in 
  the 
  other 
  they 
  resemble 
  more 
  

   closely 
  those 
  of 
  C. 
  tentaculatus 
  in 
  transverse 
  arrangement 
  

   and 
  they 
  arise 
  opposite 
  the 
  fifth 
  pair 
  of 
  bristles. 
  In 
  both 
  a 
  

   bran 
  chia 
  springs 
  in 
  front 
  of 
  the 
  dorsal 
  of 
  the 
  first 
  series 
  of 
  

   bristles. 
  The 
  first 
  ventral 
  hooks 
  occur 
  on 
  the 
  thirtieth 
  

   bristled 
  segment 
  on 
  the 
  right 
  in 
  the 
  example 
  first 
  referred 
  

   to, 
  and 
  the 
  first 
  dorsal 
  hooks 
  on 
  the 
  forty-first 
  ; 
  whereas 
  in 
  

   the 
  other 
  specimen, 
  with 
  the 
  groups 
  of 
  tentacles 
  opposite 
  

   the 
  fifth 
  bristles, 
  the 
  first 
  ventral 
  hook 
  occurs 
  on 
  the 
  nine- 
  

   teenth 
  bristled 
  segment 
  and 
  the 
  first 
  dorsal 
  hook 
  on 
  the 
  

   thirty-seventh. 
  These 
  hooks 
  are 
  slightly 
  less 
  curved 
  toward 
  

   the 
  tip 
  than 
  those 
  of 
  the 
  northern 
  form, 
  but 
  otherwise 
  are 
  

   similar. 
  The 
  bristles 
  are 
  also 
  proportionally 
  larger. 
  

  

  A 
  form 
  approaching 
  Cirratulus 
  filigerus, 
  D. 
  Chiaje, 
  from 
  

   Malahide, 
  Co. 
  Dublin, 
  obtained 
  by 
  the 
  Royal 
  Irish 
  Academy's 
  

   Expedition, 
  is 
  smaller 
  than 
  the 
  foregoing 
  species 
  and 
  

   presents 
  certain 
  differences. 
  It 
  is 
  3-4 
  inches 
  in 
  length, 
  but 
  

   of 
  similar 
  shape, 
  the 
  anus 
  being 
  dorsal, 
  with 
  a 
  short 
  cone 
  

   beneath. 
  Immediately 
  behind 
  and 
  rather 
  above 
  the 
  first 
  

   bristled 
  foot 
  is 
  a 
  branchia, 
  and 
  so 
  with 
  the 
  three 
  following. 
  

   On 
  the 
  dorsal 
  sulcus 
  between 
  the 
  fourth 
  and 
  fifth 
  bristle- 
  

   tufts 
  is 
  a 
  group 
  of 
  four 
  or 
  five 
  slender 
  branchiae. 
  Behind 
  

   the 
  foregoing 
  the 
  branchiae 
  occur 
  on 
  each 
  side 
  and 
  are 
  

   sparsely 
  distributed 
  along 
  the 
  posterior 
  region 
  almost 
  to 
  the 
  

   tip 
  of 
  the 
  tail. 
  The 
  crotchets 
  (hooks) 
  appear 
  in 
  the 
  ventral 
  

   division 
  about 
  the 
  twentieth 
  bristled 
  segment, 
  whilst 
  they 
  

   occur 
  in 
  the 
  dorsal 
  division 
  about 
  the 
  fortieth. 
  Their 
  curves 
  

   are 
  somewhat 
  more 
  pronounced 
  than 
  in 
  C. 
  tentaculatus, 
  and 
  

   in 
  the 
  posterior 
  region 
  the 
  ventral 
  are 
  considerably 
  larger 
  

   and 
  stronger 
  than 
  the 
  dorsal. 
  

  

  The 
  third 
  form 
  is 
  Cirratulus 
  cirralus, 
  O. 
  F. 
  Miiller, 
  which 
  

   is 
  generally 
  distributed 
  round 
  the 
  shores 
  of 
  Britain 
  between 
  

   tide-marks. 
  The 
  head 
  is 
  broader 
  than 
  in 
  C. 
  tentaculatus, 
  

   hoof-shaped, 
  but 
  with 
  a 
  slight 
  notch 
  in 
  the 
  centre, 
  and 
  with 
  

   two 
  well-marked 
  bands 
  of 
  eyes 
  sloping 
  obliquely 
  outward 
  

   and 
  backward. 
  The 
  body 
  is 
  3 
  to 
  4 
  inches 
  in 
  length 
  and 
  has 
  

   about 
  106 
  segments, 
  more 
  distinctly 
  outlined 
  than 
  in 
  

   C 
  tentaculatus, 
  and 
  their 
  antero-posterior 
  diameter 
  is 
  greater. 
  

   It 
  is 
  rounded 
  dorsally, 
  somewhat 
  flattened 
  ventrally, 
  where 
  a 
  

   deep 
  groove 
  runs 
  from 
  the 
  first 
  bristled 
  segment 
  backward 
  to 
  

   the 
  tail, 
  which 
  ends 
  in 
  a 
  point 
  or 
  papilla 
  ventrally, 
  with 
  the 
  

  

  