﻿262 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  i03 
  

  

  4 
  mm. 
  wide 
  without 
  setae, 
  9 
  mm. 
  wide 
  including 
  long 
  swimming 
  setae. 
  

   Two 
  atokous 
  specimens 
  from 
  Washington 
  43-48 
  mm. 
  long, 
  1.5-2 
  mm. 
  

   wide 
  without 
  setae. 
  Median 
  antenna, 
  tentacular 
  cirri 
  and 
  some 
  of 
  

   anterior 
  dorsal 
  cirri 
  somewhat 
  annulated, 
  especially 
  distaUy; 
  rest 
  of 
  

   dorsal 
  cirri 
  smooth. 
  Some 
  of 
  anterior 
  dorsal 
  cirri 
  longer 
  than 
  body 
  

   width; 
  rest 
  shorter 
  than 
  body 
  width, 
  subulate, 
  thick 
  basally, 
  tapering 
  

   distally, 
  on 
  prominent 
  cirrophores 
  which 
  may 
  be 
  as 
  long 
  as 
  parapodial 
  

   lobes. 
  Tentacular 
  segment 
  very 
  short, 
  without 
  nuchal 
  collar. 
  Blades 
  

   of 
  neurosetae 
  all 
  rather 
  short. 
  In 
  anterior 
  parapodia, 
  blades 
  of 
  upper 
  

   neurosetae 
  somewhat 
  longer 
  than 
  the 
  lower 
  ones; 
  on 
  rest 
  of 
  parapodia, 
  

   blades 
  of 
  neurosetae 
  only 
  slightly 
  different 
  in 
  length. 
  Chitinous 
  lining 
  

   of 
  proboscis 
  and 
  dorsal 
  tooth 
  light 
  to 
  darker 
  amber-colored 
  or 
  trans- 
  

   parent; 
  circular 
  anterior 
  border 
  with 
  coarse, 
  triangular 
  denticles 
  (when 
  

   transparent, 
  difficult 
  to 
  see 
  denticled 
  border). 
  Swimming 
  setae 
  begin 
  

   on 
  setiger 
  24 
  (on 
  setiger 
  19 
  in 
  specimen 
  from 
  Portage 
  Bay, 
  Alaska). 
  

   Color 
  : 
  In 
  alcohol 
  : 
  Flesh. 
  

  

  Remarks. 
  — 
  The 
  specimens 
  were 
  compared 
  with 
  the 
  type 
  of 
  Piono- 
  

   syllis 
  magnifica 
  Moore 
  (1906) 
  from 
  Port 
  Townsend, 
  Washington. 
  

   It 
  is 
  herein 
  referred 
  to 
  Eusyllis 
  since 
  the 
  composite 
  neurosetae 
  have 
  

   rather 
  short 
  blades 
  which 
  differ 
  only 
  slightly 
  in 
  length, 
  the 
  proboscis 
  

   has 
  a 
  proximal 
  and 
  a 
  distal 
  row 
  of 
  papillae, 
  and 
  the 
  anterior 
  circular 
  

   border 
  is 
  denticled 
  (difficult 
  to 
  see 
  when 
  the 
  chitinous 
  lining 
  is 
  

   transparent) 
  . 
  

  

  New 
  records. 
  — 
  Arctic 
  Alaska: 
  Off 
  Point 
  Barrow 
  base, 
  18.3 
  fms., 
  

   pebbles-mud 
  (1 
  station, 
  2 
  specimens). 
  West 
  Coast 
  North 
  America: 
  

   Albatross 
  surface 
  station. 
  Portage 
  Bay, 
  Alaska; 
  Washington 
  Sound, 
  

   Pettibone. 
  

  

  Distribviion. 
  — 
  Arctic 
  Alaska 
  to 
  Washington; 
  north 
  Japan 
  Sea. 
  In 
  

   16 
  to 
  302.8 
  fathoms; 
  epitokes 
  at 
  surface. 
  

  

  Genus 
  Pionosyllis 
  Malmgren, 
  1867 
  

   Pionosyllis 
  compacta 
  Malmgren, 
  1867 
  

  

  Figure 
  28, 
  j 
  

  

  Pionosyllis 
  compacta 
  Malmgren, 
  1867, 
  p. 
  40, 
  fig. 
  48. 
  — 
  Augener, 
  1928, 
  p. 
  722. 
  — 
  

   Annenkova, 
  1934, 
  p. 
  322. 
  

  

  Description. 
  — 
  Anterior 
  ends 
  only 
  of 
  two 
  small 
  specimens, 
  up 
  to 
  

   1.5 
  mm. 
  wide 
  without 
  setae 
  (8-10 
  mm. 
  long, 
  1 
  mm. 
  wide 
  — 
  Malmgren, 
  

   1867). 
  Body 
  flattened 
  ventraUy, 
  arched 
  dorsally, 
  fragile, 
  with 
  seg- 
  

   ments 
  crowded. 
  Prostomium 
  subrectangular, 
  wider 
  than 
  long; 
  four 
  

   eyes 
  rather 
  large, 
  in 
  trapezoidal 
  arrangement; 
  palps 
  squarish, 
  fused 
  

   basally, 
  widely 
  separated 
  distally. 
  Tentacular 
  segment 
  without 
  

   nuchal 
  collar. 
  Antennae, 
  tentacular, 
  and 
  dorsal 
  cirri 
  smooth, 
  without 
  

   articulations, 
  filiform 
  to 
  rather 
  thick, 
  breaking 
  off 
  readily; 
  most 
  of 
  

  

  