﻿Gatty 
  Marine 
  Laboratory^ 
  St. 
  Andrews. 
  103 
  

  

  Canadian 
  forms 
  they 
  are 
  nearly 
  half 
  tlie 
  length 
  of 
  the 
  body 
  

   in 
  the 
  preparations. 
  

  

  Body 
  somewhat 
  clavate 
  in 
  outline, 
  though 
  a 
  slight 
  narrow- 
  

   ing 
  occurs 
  anteriorly 
  from 
  the 
  eighth 
  foot 
  forward, 
  and 
  

   behind 
  this 
  it 
  diminishes 
  to 
  the 
  tail, 
  which 
  in 
  one 
  presented 
  

   a 
  thick 
  short 
  cirrus 
  on 
  one 
  side. 
  The 
  dorsum 
  is 
  smoothly 
  

   rounded 
  throughout, 
  whilst 
  the 
  ventral 
  surface 
  is 
  marked 
  

   from 
  the 
  mouth 
  to 
  tlie 
  tenth 
  bristled 
  segment 
  by 
  a 
  thickened 
  

   glandular 
  layer 
  in 
  each 
  segment. 
  Then 
  a 
  groove 
  appears 
  

   in 
  the 
  middle 
  line, 
  and 
  is 
  continued 
  to 
  the 
  tip 
  of 
  the 
  tail. 
  

   In 
  a 
  large 
  example 
  the 
  vent 
  presented 
  a 
  notch 
  dorsally 
  and 
  

   a 
  crenate 
  edge 
  beneath, 
  and 
  in 
  a 
  perfect 
  Canadian 
  example 
  

   in 
  a 
  tube 
  a 
  short 
  cirrus 
  occurred 
  on 
  each 
  side. 
  Malmgren's 
  

   specimens 
  had 
  been 
  imperfect. 
  

  

  External 
  to 
  the 
  branchiae 
  is 
  the 
  small 
  first 
  setigerous 
  

   process, 
  which 
  bears 
  a 
  tuft 
  of 
  bristles. 
  This 
  and 
  the 
  next 
  

   two 
  are 
  rather 
  dorsal 
  than 
  lateral, 
  but 
  they 
  soon 
  become 
  

   lateral 
  and 
  project 
  from 
  the 
  region 
  as 
  long 
  processes 
  sloping 
  

   outward 
  and 
  backward. 
  

  

  Each 
  bristle-tuft 
  has 
  a 
  longer 
  and 
  a 
  shorter 
  series 
  of 
  

   translucent 
  bristles, 
  with 
  a 
  slightly 
  curved 
  tip 
  furnished 
  with 
  

   somewhat 
  narrow 
  wings. 
  Tlie 
  shaft 
  is 
  minutely 
  striated 
  

   longitudinally, 
  and 
  widens 
  a 
  little 
  as 
  it 
  approaches 
  the 
  tip. 
  

  

  The 
  hooks 
  have 
  a 
  somewhat 
  triangular 
  outline 
  fr,)m 
  the 
  

   breadth 
  of 
  the 
  crown, 
  which 
  is 
  slightly 
  sinuous. 
  The 
  pos- 
  

   terior 
  outline 
  curves 
  to 
  the 
  rounded 
  prow, 
  which 
  is 
  carried 
  

   to 
  the 
  line 
  of 
  the 
  teeth. 
  The 
  first 
  tooth 
  is 
  as 
  large 
  as 
  the 
  

   second, 
  and 
  the 
  two 
  following 
  are 
  similar, 
  the 
  last 
  being 
  

   slightly 
  broader 
  at 
  the 
  base 
  from 
  the 
  curve 
  of 
  the 
  gulf 
  

   between 
  it 
  and 
  the 
  prow. 
  The 
  posterior 
  hooks 
  are 
  smaller, 
  

   but 
  they 
  have 
  the 
  same 
  form 
  and 
  structure. 
  Moreover, 
  

   the 
  papillae 
  or 
  lamellae 
  on 
  which 
  they 
  occur 
  are 
  the 
  only 
  

   processes 
  posteriorly, 
  and 
  are 
  twelve 
  or 
  thirteen 
  in 
  number. 
  

  

  The 
  tube 
  is 
  not 
  mentioned 
  by 
  Malmgren, 
  but 
  is 
  composed 
  

   of 
  a 
  lining 
  of 
  tough 
  secretion 
  with 
  a 
  few 
  sand-grains 
  and 
  

   free 
  sheds 
  of 
  mucus, 
  which 
  give 
  it 
  the 
  aspect 
  of 
  being 
  coated 
  

   with 
  minute 
  algae. 
  

  

  The 
  fifth 
  representative 
  is 
  Ainage 
  auricula, 
  Malmgren, 
  

   procured 
  only 
  in 
  deep 
  water 
  by 
  the 
  ' 
  Knight 
  Errant.' 
  It 
  

   is 
  a 
  small 
  form 
  about 
  | 
  of 
  an 
  inch 
  in 
  length 
  with 
  a 
  some- 
  

   what 
  broad 
  and 
  blunt 
  anterior 
  end, 
  the 
  brachiae 
  in 
  the 
  

   preparation 
  being 
  on 
  the 
  anterior 
  ridge, 
  the 
  prostomium 
  

   being 
  doubled 
  downward 
  as 
  a 
  small 
  and 
  somewhat 
  bifid 
  

   process, 
  the 
  fillets 
  of 
  the 
  peristomium 
  (Fauvel's 
  rudimentary 
  

   palps) 
  supporting 
  it 
  laterally 
  and 
  posteriorly. 
  The 
  mouth 
  

  

  