﻿MARINE 
  POLYCHAETE 
  WORMS 
  — 
  PETTIBONE 
  267 
  

  

  ventral 
  cirri 
  short, 
  conical, 
  or 
  foliaceous; 
  with 
  anterior 
  and 
  posterior 
  

   lamellae 
  more 
  or 
  less 
  developed 
  (fig. 
  30, 
  k-^). 
  A 
  single 
  anal 
  cirrus. 
  

   Proboscis 
  eversible, 
  strong, 
  muscular, 
  a 
  pah- 
  of 
  horny 
  jaws 
  wdthin 
  the 
  

   pharynx, 
  with 
  rows 
  of 
  soft 
  papillae 
  and 
  a 
  crown 
  of 
  terminal, 
  bifid 
  

   papillae. 
  Move 
  rapidly 
  with 
  undulating 
  motion; 
  usually 
  in 
  sand 
  

   or 
  mud. 
  

  

  Represented 
  by 
  a 
  single 
  genus 
  and 
  four 
  species. 
  

  

  (ienus 
  Nephtys 
  Cuvier, 
  1817 
  

  

  The 
  four 
  species 
  represented 
  have 
  numerous 
  segments 
  (65-150), 
  

   tapered 
  posteriorly 
  and 
  slightly 
  anteriorly. 
  Prostomium 
  pentagonal 
  

   to 
  quadrate, 
  with 
  antennae 
  conical, 
  subequal, 
  or 
  more 
  ventral 
  pair 
  

   slightly 
  larger, 
  without 
  eyes, 
  with 
  pair 
  of 
  nuchal 
  papillae 
  at 
  postectal 
  

   margins 
  (may 
  be 
  inverted 
  or 
  everted; 
  fig. 
  30, 
  j). 
  Tentacular 
  or 
  first 
  

   segment 
  with 
  both 
  dorsal 
  and 
  ventral 
  tentacular 
  cu-ri. 
  Parapodial 
  

   rami 
  with 
  anterior 
  lamellae 
  rudimentary 
  or 
  lacking, 
  with 
  posterior 
  

   lamellae 
  developed 
  m 
  varying 
  degrees, 
  with 
  branchiae 
  recurved 
  (con- 
  

   vex 
  side 
  toward 
  lateral 
  side 
  of 
  body, 
  fig. 
  30, 
  Ar-n). 
  Ventral 
  cu-ri 
  short, 
  

   conical. 
  Proboscis 
  with 
  22 
  long 
  terminal 
  papillae 
  (10 
  pairs 
  bifid, 
  and 
  

   a 
  single 
  dorsal 
  and 
  ventral 
  one), 
  with 
  22 
  longitudinal 
  rows 
  of 
  sub- 
  

   terminal 
  papillae, 
  four 
  to 
  eight 
  per 
  row, 
  decreasing 
  in 
  size 
  basally. 
  

  

  Key 
  to 
  the 
  species 
  of 
  Nephtys 
  from 
  Point 
  Barrow 
  

  

  1. 
  Branchiae 
  cirriform, 
  sickle-shaped, 
  with 
  dorsal 
  'curi 
  digitiform 
  (fig. 
  30, 
  I, 
  n). 
  

  

  Proboscis 
  with 
  a 
  long 
  median 
  dorsal 
  papilla 
  2 
  

  

  Branchiae 
  foliaceous 
  or 
  cirriform 
  and 
  inflated 
  basally, 
  rudimentary 
  or 
  absent 
  

   on 
  last 
  15-30 
  segments, 
  with 
  dorsal 
  cirri 
  flattened, 
  triangular, 
  pointed 
  (fig. 
  

   30, 
  k, 
  m). 
  Proboscis 
  without 
  a 
  long 
  median 
  dorsal 
  papilla; 
  proximal 
  surface 
  

   of 
  proboscis 
  ridged 
  (may 
  be 
  low 
  tubercles 
  in 
  N. 
  discors) 
  3 
  

  

  2. 
  Branchiae 
  begin 
  on 
  setigers 
  3 
  or 
  4, 
  continuing 
  to 
  almost 
  posterior 
  end; 
  acicular 
  

  

  lobes 
  rounded 
  or 
  sUghtly 
  bilobed, 
  especially 
  anteriorly 
  (fig. 
  30, 
  I). 
  Neuro- 
  

   podial 
  postsetal 
  lamellae 
  extend 
  well 
  beyond 
  the 
  acicular 
  lobes, 
  bilobed 
  or 
  

   irregularly 
  sinuous. 
  Setae 
  very 
  long, 
  flowing. 
  Proximal 
  surface 
  of 
  pro- 
  

   boscis 
  smooth 
  or 
  furrowed 
  N. 
  longosetosa 
  

  

  Branchiae 
  begin 
  on 
  setigers 
  5-8, 
  rudimentary 
  on 
  last 
  20-30 
  segments. 
  Acicular 
  

   lobes 
  deeply 
  bilobed 
  in 
  anterior 
  and 
  median 
  regions 
  (fig. 
  30, 
  n) 
  . 
  Neuropodial 
  

   postsetal 
  lamellae 
  about 
  same 
  length 
  as 
  or 
  only 
  slightly 
  surpassing 
  the 
  

   acicular 
  lobes. 
  Setae 
  shorter. 
  Proximal 
  surface 
  of 
  proboscis 
  tubercled. 
  

  

  N. 
  ciliata 
  

  

  3. 
  Branchiae 
  begin 
  on 
  setiger 
  6, 
  inflated 
  basally, 
  digitiform, 
  recurved 
  distally 
  

  

  (fig. 
  30, 
  m). 
  Acicular 
  lobes 
  unequally 
  bilobed, 
  rounded 
  in 
  posterior 
  region. 
  

   Postsetal 
  lamellae 
  of 
  anterior 
  and 
  median 
  regions 
  large, 
  foliaceous, 
  extending 
  

   well 
  beyond 
  the 
  acicular 
  lobes; 
  in 
  posterior 
  region, 
  extend 
  only 
  slightly 
  

  

  beyond 
  N. 
  discors 
  

  

  Branchiae 
  begin 
  on 
  setigers 
  8-14, 
  thick, 
  wide, 
  foliaceous 
  (fig. 
  30, 
  k). 
  Acicular 
  

   lobes 
  rounded 
  to 
  conical. 
  Postsetal 
  lamellae 
  shorter 
  than, 
  as 
  long 
  as, 
  or 
  

   only 
  slightly 
  longer 
  than 
  the 
  acicular 
  lobes 
  N. 
  paradoxa 
  

  

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