﻿MARINE 
  POLYCHAETE 
  WORMS 
  — 
  PETTIBONE 
  

  

  211 
  

  

  s, 
  seta 
  uL, 
  upper 
  lip 
  

  

  scH, 
  scaphal 
  hook 
  un, 
  uncinus 
  (very 
  small 
  and 
  short, 
  

  

  set, 
  setigerous 
  segment 
  or 
  setiger 
  flattened 
  setal 
  hooks) 
  

  

  setLo, 
  setigerous 
  lobe 
  unPi, 
  uncinigerous 
  pinnule 
  (flattened 
  

  

  sh, 
  shaft 
  of 
  seta 
  (basal 
  part 
  of 
  com- 
  parapodial 
  ramus 
  bearing 
  numerous 
  

  

  posite 
  or 
  jointed 
  seta) 
  uncini 
  or 
  small 
  setal 
  hooks) 
  

  

  spH, 
  special 
  hook 
  unTo, 
  uncinigerous 
  torus 
  (low, 
  in- 
  

  

  tC, 
  tentacular 
  cirrus 
  flated 
  parapodial 
  ramus 
  bearing 
  

  

  tF, 
  tentacular 
  filament 
  numerous 
  uncini 
  or 
  small 
  setal 
  

  

  tM, 
  tentacular 
  membrane 
  hooks) 
  

  

  tS, 
  tentacular 
  segment 
  or 
  peristomium 
  vC, 
  ventral 
  cirrus 
  

  

  (anterior 
  modified 
  segments 
  around 
  vF, 
  ventral 
  faecal 
  groove 
  

  

  mouth) 
  vL, 
  ventral 
  lobe 
  

  

  th, 
  thoracic 
  region 
  vPa, 
  ventral 
  papilla 
  

  

  thM, 
  thoracic 
  membrane 
  vSh, 
  ventral 
  shield 
  

  

  to, 
  tooth 
  Ven, 
  ventral 
  

  

  tor, 
  torus 
  (low, 
  inflated 
  parapodial 
  w, 
  basal 
  crenulate 
  wing 
  

  

  lobe) 
  

  

  Order 
  POLYCHAETA 
  

   Key 
  to 
  the 
  families 
  of 
  Polychaeta 
  from 
  Point 
  Barrow 
  

  

  1. 
  Dorsal 
  surface 
  more 
  or 
  less 
  completely 
  covered 
  by 
  paired 
  overlapping 
  scales 
  

  

  or 
  elytra 
  (fig. 
  26, 
  a) 
  5 
  

  

  Dorsal 
  surface 
  not 
  covered 
  by 
  elytra 
  2 
  

  

  2. 
  Anterior 
  end 
  more 
  or 
  less 
  concealed 
  by 
  feathery 
  tentacles 
  (fig. 
  38, 
  a), 
  chiti- 
  

  

  nous 
  golden 
  setae 
  forming 
  an 
  operculum 
  (figs. 
  34, 
  n; 
  35, 
  d), 
  long 
  setae 
  

   directed 
  forward 
  forming 
  a 
  cephahc 
  cage, 
  or 
  long 
  filamentous 
  outgrowths 
  

  

  (fig. 
  36, 
  /) 
  . 
  With 
  more 
  or 
  less 
  permanent 
  tubes 
  6 
  

  

  Anterior 
  end 
  otherwise 
  3 
  

  

  3. 
  Body 
  thickly 
  papillated, 
  grub-shaped 
  21 
  

  

  Body 
  smooth 
  or 
  finely 
  granulated 
  4 
  

  

  4. 
  Prostomium 
  with 
  conspicuous 
  antennae, 
  with 
  or 
  without 
  fleshy 
  palps 
  (figs. 
  

  

  26-30), 
  or 
  prostomium 
  or 
  an 
  anterior 
  segment 
  with 
  pair 
  of 
  long, 
  prehensile, 
  

  

  tentacular 
  palps 
  (fig. 
  32, 
  i) 
  13 
  

  

  Prostomium 
  without 
  palps 
  and 
  without 
  conspicuous 
  antennae 
  (fig. 
  32, 
  a) 
  or 
  

   with 
  2 
  pairs 
  minute 
  antennae 
  (figs. 
  30, 
  j; 
  31, 
  o, 
  e) 
  18 
  

  

  5. 
  Elytra 
  on 
  all 
  segments 
  of 
  posterior 
  region 
  (at 
  least 
  from 
  segment 
  29 
  on). 
  

  

  Dorsal 
  cirri 
  lacking 
  Sigalionidae 
  (p. 
  228) 
  

  

  Elytra 
  not 
  on 
  all 
  segments 
  of 
  posterior 
  region. 
  With 
  paired 
  dorsal 
  cirri 
  on 
  

   segments 
  without 
  elytra 
  (fig. 
  26, 
  a) 
  Polynoidae 
  (p. 
  213) 
  

  

  6. 
  Anterior 
  end 
  with 
  branchial 
  plume 
  (fig. 
  38, 
  a) 
  7 
  

  

  Anterior 
  end 
  without 
  branchial 
  plume 
  8 
  

  

  7. 
  Branchial 
  filaments 
  without 
  operculum. 
  Without 
  thoracic 
  membrane. 
  

  

  Tube 
  gelatinous, 
  membranous, 
  or 
  horny, 
  covered 
  or 
  not 
  with 
  mud, 
  sand, 
  

  

  gravel, 
  and 
  debris 
  Sabellidae 
  (p. 
  332) 
  

  

  Usually 
  1 
  or 
  2 
  opercula 
  on 
  modified 
  branchial 
  filaments 
  (fig. 
  39, 
  u) 
  . 
  Usually 
  

   with 
  thoracic 
  membrane 
  (fig. 
  39, 
  u). 
  Tube 
  calcareous.. 
  Serpulidae 
  (p. 
  342) 
  

  

  8. 
  Anterior 
  end 
  with 
  chitinous, 
  golden 
  setae 
  forming 
  an 
  operculum 
  (figs. 
  34, 
  

  

  n; 
  35, 
  d). 
  In 
  free, 
  conical, 
  sandy 
  tubes 
  or 
  concreted 
  sandy 
  tubes 
  attached 
  

  

  to 
  rocks, 
  shells, 
  etc 
  12 
  

  

  Anterior 
  end 
  without 
  opercular 
  setae. 
  Tube 
  otherwise 
  9 
  

  

  