﻿Gatiy 
  Marine 
  Laboratory 
  ^ 
  St. 
  Andrews. 
  169 
  

  

  body 
  is 
  rounded 
  dorsally, 
  slightly 
  flattened 
  ventrally, 
  and. 
  

   the 
  latter 
  surface 
  has 
  a 
  median 
  groove. 
  Both 
  dorsal 
  and. 
  

   ventral 
  bristles 
  (PL 
  VII. 
  fig. 
  8) 
  are 
  throughout 
  capillary, 
  and 
  

   little 
  difference 
  exists 
  between 
  the 
  most 
  anterior 
  and 
  those 
  

   at 
  the 
  tip 
  of 
  the 
  tail. 
  This, 
  therefore, 
  belongs 
  to 
  the 
  

   first 
  series 
  of 
  De 
  St. 
  Joseph, 
  viz., 
  those 
  with 
  capillary 
  bristles 
  

   throughout. 
  

  

  Chcetozone 
  setosa, 
  var. 
  canadensis. 
  Stations 
  32-34 
  — 
  1873. 
  

  

  In 
  this 
  form, 
  which 
  has 
  a 
  general 
  resemblance 
  to 
  C. 
  setosa, 
  

   though 
  the 
  body 
  is 
  more 
  flattened 
  posteriorly, 
  the 
  anterior 
  

   bristles 
  differ 
  from 
  those 
  of 
  C. 
  setosa, 
  for 
  example 
  at 
  the 
  tenth 
  

   foot 
  in 
  having 
  a 
  distinct 
  curve 
  at 
  the 
  end 
  of 
  the 
  shaft, 
  and 
  

   the 
  long 
  tip 
  widens 
  into 
  a 
  flat 
  blade 
  (PI. 
  VII. 
  fig. 
  9), 
  which 
  

   then 
  tapers 
  to 
  a 
  fine 
  tip; 
  the 
  whole, 
  however, 
  is 
  considerably 
  

   shorter 
  than 
  in 
  the 
  typical 
  C. 
  setosa. 
  The 
  general 
  arrange- 
  

   ment 
  of 
  the 
  posterior 
  hooks 
  resembles 
  that 
  of 
  C. 
  setosa, 
  

   though 
  the 
  crotchets 
  (PI. 
  VII. 
  fig. 
  9 
  a) 
  are 
  considerably 
  

   larger 
  and 
  similarly 
  alternate 
  with 
  a 
  long 
  capillary 
  bristle 
  

   (PI. 
  VII. 
  fig. 
  9 
  b). 
  It 
  would 
  be 
  difficult 
  to 
  draw 
  a 
  specific 
  

   distinction, 
  however, 
  from 
  mere 
  size. 
  

  

  Chcetozone 
  whiteavesi. 
  

  

  Dredged 
  in 
  the 
  Gulf 
  of 
  St. 
  Lawrence, 
  Canada, 
  by 
  

   Dr. 
  Whiteaves 
  at 
  Station 
  A. 
  6 
  in 
  1872. 
  

  

  This 
  species 
  has 
  much 
  of 
  the 
  appearance 
  anteriorly 
  of 
  

   Cl/cptozotie 
  setosa, 
  the 
  snout 
  being 
  acutely 
  pointed, 
  and 
  the 
  

   tentacles 
  and 
  branchiae 
  being 
  similar. 
  The 
  body 
  is 
  rounded 
  

   dorsally 
  in 
  front, 
  then 
  is 
  somewhat 
  flattened, 
  and 
  again 
  is 
  

   rounded 
  toward 
  the 
  tail, 
  which 
  is 
  only 
  a 
  little 
  tapered, 
  and 
  

   has 
  a 
  terminal 
  anus 
  with 
  two 
  small 
  rounded 
  papillae 
  ventrally. 
  

   The 
  ventral 
  surface 
  of 
  the 
  body 
  is 
  marked 
  by 
  a 
  median 
  

   groove 
  from 
  end 
  to 
  end, 
  whilst 
  the 
  sides 
  are 
  flanked 
  by 
  tufts 
  

   of 
  long 
  capillary 
  bristles 
  from 
  the 
  front 
  to 
  the 
  middle 
  of 
  

   the 
  body, 
  and 
  by 
  shorter 
  capillary 
  bristles 
  from 
  the 
  middle 
  

   to 
  the 
  tip 
  of 
  the 
  tail. 
  This 
  arrangement 
  at 
  once 
  differentiates 
  

   the 
  species 
  from 
  C. 
  setosa 
  and 
  allied 
  forms, 
  for 
  their 
  crotchets 
  

   are 
  conspicuous 
  posteriorly. 
  The 
  gut 
  shows 
  through 
  the 
  

   integumentary 
  layers 
  in 
  the 
  region 
  behind 
  the 
  middle 
  — 
  

   especially 
  dorsally 
  — 
  the 
  colour 
  being 
  dull 
  pink. 
  

  

  The 
  bristles 
  throughout 
  are 
  capillary, 
  the 
  dorsal 
  in 
  front 
  

   (PL 
  VII. 
  fig. 
  10) 
  being 
  considerably 
  longer 
  than 
  the 
  ventral 
  

   and 
  stronger 
  than 
  those 
  in 
  the 
  succeeding 
  region. 
  Both 
  

   dorsal 
  and 
  ventral 
  tufts 
  are 
  shorter 
  in 
  the 
  middle 
  of 
  the 
  

   body, 
  and 
  the 
  disproportion 
  between 
  dorsal 
  and 
  ventral 
  is 
  

   less 
  marked, 
  whilst 
  posteriorly 
  they 
  are 
  almost 
  equal. 
  

  

  