﻿MARESTE 
  POLYCHAETE 
  WORMS 
  — 
  ^PETTIBONE 
  295 
  

  

  Family 
  Opheliidae 
  

  

  Body 
  relatively 
  short, 
  often 
  grublike 
  or 
  lancet-shaped. 
  Integument 
  

   smooth 
  or 
  granulated; 
  segmental 
  grooves 
  weak 
  or 
  obscured 
  by 
  super- 
  

   ficial 
  annuli. 
  Prostomium 
  small, 
  conical, 
  without 
  appendages; 
  pair 
  

   of 
  eversible 
  nuchal 
  organs 
  (fig. 
  33, 
  I, 
  o). 
  Proboscis 
  eversible, 
  saclike, 
  

   unarmed. 
  Parapodia 
  biramous, 
  lobes 
  reduced 
  or 
  lacking; 
  setae 
  simple, 
  

   capillary 
  (fig. 
  33, 
  m, 
  q). 
  Without 
  dorsal 
  cirri; 
  rarely 
  with 
  ventral 
  

   cirri. 
  Branchiae 
  paired, 
  cirriform, 
  inserted 
  near 
  parapodia, 
  extending 
  

   along 
  most 
  of 
  body 
  (may 
  be 
  lacking). 
  Pygidium 
  forming 
  an 
  anal 
  

   cylinder, 
  a 
  flap, 
  or 
  knob, 
  with 
  or 
  without 
  cirri 
  (fig. 
  33, 
  n, 
  p). 
  

  

  Represented 
  by 
  two 
  genera 
  and 
  two 
  species 
  from 
  Point 
  Barrow. 
  

   Both 
  genera 
  have 
  paired 
  cirriform 
  branchiae 
  along 
  most 
  of 
  length 
  of 
  

   body; 
  without 
  lateral 
  eyes 
  along 
  body. 
  

  

  Key 
  to 
  the 
  genera 
  of 
  Opheliidae 
  from 
  Point 
  Barrow 
  

  

  1. 
  Body 
  lancet-shaped; 
  ventral 
  surface 
  thick, 
  solelike, 
  formed 
  by 
  2 
  thick 
  longi- 
  

   tudinal 
  muscular 
  columns, 
  with 
  midventral 
  and 
  lateral 
  grooves 
  along 
  length 
  

   of 
  body. 
  Parapodial 
  lobes 
  small, 
  along 
  lateral 
  grooves 
  (fig. 
  33, 
  m). 
  

  

  Ammotrypane 
  (p. 
  295) 
  

   Body 
  cylindrical, 
  grub-shaped, 
  without 
  midventral 
  or 
  lateral 
  grooves. 
  Para- 
  

   podial 
  lobes 
  absent, 
  the 
  simple, 
  capillary 
  noto- 
  and 
  neurosetae 
  emerging 
  

   directly 
  from 
  body 
  wall 
  (fig. 
  33, 
  q) 
  Travisia 
  (p. 
  296) 
  

  

  G^nus 
  Ammotrypane 
  Ratlike, 
  1843 
  

   Ammotrypane 
  breviata 
  Ehlers, 
  1913 
  

  

  Figure 
  33, 
  l-n 
  

  

  Ammotrypane 
  breviata 
  Ehlers, 
  1913, 
  p. 
  523, 
  pi. 
  39, 
  figs. 
  1-7. 
  — 
  Monro, 
  1930, 
  p. 
  

  

  165; 
  1936, 
  p. 
  165. 
  

   Ophelina 
  groenlandica 
  St0p-Bowitz, 
  1948b, 
  p. 
  20, 
  fig. 
  6. 
  

  

  Description. 
  — 
  Length 
  6-7 
  mm., 
  width 
  0.3 
  mm., 
  setigerous 
  segments 
  

   26 
  or 
  27 
  (up 
  to 
  34 
  mm. 
  long, 
  2 
  mm. 
  wide, 
  26-28 
  segments 
  — 
  Monro, 
  

   1930, 
  1936). 
  Body 
  rigid, 
  tapered 
  at 
  both 
  ends, 
  smooth, 
  without 
  

   superficial 
  segmental 
  divisions, 
  Prostomium 
  conical, 
  the 
  anterior 
  tip 
  

   constricted 
  to 
  form 
  a 
  small 
  globular 
  palpode; 
  prostomial 
  tip 
  may 
  be 
  

   partly 
  telescoped 
  into 
  rest 
  of 
  prostomium; 
  pair 
  of 
  eversible 
  nuchal 
  

   organs 
  at 
  level 
  of 
  parapodia. 
  Parapodia 
  with 
  two 
  groups 
  of 
  fine 
  

   capillary 
  setae, 
  the 
  dorsal 
  group 
  slightly 
  longer 
  than 
  the 
  ventral. 
  

   Branchiae 
  begin 
  on 
  setiger 
  2, 
  absent 
  on 
  last 
  three 
  to 
  five 
  setigers; 
  

   branchiae 
  slender, 
  cirriform, 
  subequal. 
  Pygidium 
  forming 
  a 
  short, 
  

   somewhat 
  contractile 
  anal 
  cylinder, 
  closed 
  on 
  aU 
  sides, 
  somewhat 
  

   lobulate 
  or 
  papillate 
  on 
  open 
  posterior 
  end. 
  Eversible 
  proboscis 
  

   saclike, 
  smooth. 
  Color: 
  In 
  alcohol: 
  Without 
  color 
  or 
  may 
  be 
  darkly 
  

   pigmented 
  laterally 
  along 
  posterior 
  three 
  setigerous 
  segments 
  and 
  

   proximal 
  part 
  of 
  anal 
  tube. 
  

  

  