﻿[35] 
  ANNELIDA 
  CH^TOPODA. 
  741 
  

  

  Specimen 
  of 
  the 
  length 
  just 
  given 
  had 
  but 
  thirteen 
  pairs 
  of 
  branchiae; 
  

   a 
  siDgle 
  larger 
  specimen 
  had 
  twenty 
  pairs; 
  its 
  color 
  was 
  reddish-brown 
  

   in 
  front, 
  passing 
  into 
  brown 
  farther 
  back, 
  ventral 
  surface 
  white. 
  

  

  Common 
  in 
  mud 
  and 
  sandy 
  mud 
  ; 
  6-12 
  fathoms. 
  

  

  Family 
  OIRRATULIMi. 
  

  

  CIBBATULUS 
  Lanarck. 
  

  

  Cirratulus 
  CIRRATUS 
  Malmgren. 
  

  

  Malmgken. 
  Anuulata 
  Polych., 
  p. 
  95. 
  1867. 
  

   Rare 
  ; 
  low 
  water 
  ; 
  sand. 
  

  

  DODECACERIA 
  (Ersted. 
  

  

  DODECACERIA 
  CONCHARUM 
  (Ersted. 
  

  

  (Ersted. 
  Ann. 
  Dan. 
  Consp., 
  p. 
  44, 
  fig. 
  99. 
  1843. 
  

   Verrill. 
  Proc. 
  U. 
  S. 
  National 
  Museum, 
  p. 
  178. 
  1879. 
  

  

  The 
  arrangement 
  of 
  setae 
  was 
  not 
  exactly 
  the 
  same, 
  on 
  our 
  specimens, 
  

   as 
  that 
  given 
  by 
  Professor 
  Verrill. 
  

   Rare 
  ; 
  25-30 
  fathoms. 
  

  

  CH^TOZONE 
  Malmgren. 
  

  

  We 
  found 
  many 
  specimens 
  of 
  a 
  form 
  which 
  seems 
  certainly 
  to 
  be 
  

   Chcvtozone 
  setosa 
  Malmgren, 
  but 
  which 
  differ 
  from 
  his 
  specimens 
  in 
  

   having 
  a 
  pair 
  of 
  tentacular 
  cirri, 
  and 
  also 
  in 
  having, 
  normally, 
  dorsal 
  

   cirri 
  on 
  all 
  segments, 
  or 
  at 
  least 
  scattered 
  along 
  the 
  entire 
  length 
  of 
  the 
  

   body. 
  

  

  Oh^htozone 
  setosa 
  Malmgren. 
  

  

  The 
  head 
  is 
  acute, 
  conical; 
  first 
  three 
  segments 
  without 
  appendages; 
  

   fourth 
  segment 
  with 
  a 
  pair 
  of 
  long, 
  stout, 
  canaliculated, 
  tentacular 
  cirri. 
  

  

  The 
  dorsal 
  cirri 
  are 
  not 
  limited 
  to 
  the 
  anterior 
  segments, 
  but 
  may 
  exist 
  

   on 
  any 
  segment, 
  though 
  they 
  readily 
  fall 
  off, 
  especially 
  along 
  the 
  pos- 
  

   terior 
  two-thirds. 
  The 
  cirri 
  of 
  the 
  fifth 
  and 
  sixth 
  segments 
  are 
  often 
  

   longer 
  and 
  larger 
  than 
  the 
  others, 
  but 
  have 
  the 
  same 
  structure. 
  The 
  

   anal 
  segment 
  terminates 
  in 
  a 
  thin, 
  horizontal, 
  semicircular 
  plate. 
  

  

  Anterior 
  fourth 
  of 
  the 
  body 
  yellowish-white 
  ; 
  posterior 
  three-fourths 
  

   dark 
  purple; 
  or 
  the 
  entire 
  body 
  may 
  be 
  colorless. 
  

  

  Common 
  on 
  sandy 
  and 
  shelly 
  bottoms; 
  6-12 
  fathoms. 
  

  

  THARYX, 
  n. 
  g. 
  

  

  Head 
  and 
  first 
  two 
  segments 
  without 
  appendages. 
  One 
  pair 
  of 
  ten- 
  

   tacular 
  cirri 
  ; 
  next 
  segment 
  with 
  dorsal 
  cirri, 
  but 
  without 
  setse 
  ; 
  all 
  other 
  

   segments 
  (normally) 
  with 
  dorsal 
  cirri; 
  setae 
  capillary. 
  

  

  