﻿718 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [12] 
  

  

  at 
  about 
  the 
  middle 
  point, 
  as 
  in 
  a 
  tfyllides 
  convoluta 
  ; 
  in 
  preserved 
  speci- 
  

   mens 
  they 
  can 
  be 
  seen 
  only 
  with 
  difficulty. 
  

  

  The 
  contents 
  of 
  the 
  intestines 
  were 
  dark 
  brown 
  to 
  black. 
  

  

  The 
  setae 
  of 
  the 
  anterior 
  segments 
  are 
  very 
  numerous, 
  forming 
  dense 
  

   bundles 
  ; 
  they 
  decrease 
  rapidly 
  in 
  number 
  after 
  the 
  fifth 
  segment. 
  The 
  

   simple 
  seta 
  of 
  the 
  first 
  five 
  segments 
  is 
  recurved 
  at 
  the 
  end, 
  flattened 
  and 
  

   denticulated 
  along 
  the 
  recurved 
  edge 
  as 
  figured 
  by 
  Marion 
  and 
  Bob- 
  

   retzky 
  ; 
  but 
  after 
  the 
  fifth 
  segmentthis 
  seta 
  is 
  replaced 
  by 
  a 
  longcapillary 
  

   seta, 
  as 
  long 
  as 
  the 
  longest 
  compound 
  seta*. 
  We 
  have 
  already 
  pointed 
  

   out 
  the 
  differences 
  in 
  the 
  seta 
  1 
  of 
  this 
  species 
  as 
  figured 
  by 
  Marion 
  and 
  

   Bobretzky 
  and 
  Marentzeller 
  (see 
  Provincetown 
  paper). 
  In 
  fact 
  if 
  one 
  

   were 
  to 
  follow 
  these 
  descriptions 
  and 
  figures 
  carefully, 
  it 
  would 
  be 
  

   necessary 
  to 
  regard 
  them 
  as 
  representing 
  distinct 
  species, 
  and 
  our 
  speci- 
  

   mens 
  would 
  then 
  stand 
  for 
  still 
  another 
  species. 
  This 
  may 
  well 
  bo 
  the 
  

   case, 
  but 
  if 
  Langerhaus's 
  identification 
  is 
  correct, 
  it 
  is 
  probable 
  that 
  

   our 
  form 
  will 
  fall 
  in 
  with 
  the 
  others. 
  

  

  Sand, 
  gravel, 
  mud 
  ; 
  low 
  water 
  to 
  25 
  fathoms. 
  

  

  STREPTOSYLLLS 
  Webster 
  & 
  Benedict. 
  

   Streptosyllis 
  yarians, 
  n. 
  sp. 
  

  

  (Pi.. 
  II, 
  Figs. 
  24-31 
  ; 
  Pl. 
  Ill, 
  Figs. 
  32-34, 
  a 
  b.) 
  

  

  Head, 
  quadrangular 
  (fijr. 
  24) 
  width 
  nearly 
  double 
  the 
  length; 
  the 
  line 
  

   of 
  separation 
  between 
  the 
  head 
  and 
  palpi 
  very 
  indistinct 
  ; 
  posterior 
  mar- 
  

   gin 
  slightly 
  concave. 
  There 
  are 
  four 
  eyes, 
  dark 
  red; 
  posterior 
  pair 
  

   largest, 
  a 
  little 
  behind 
  the 
  middle 
  line, 
  lateral, 
  circular; 
  this 
  pair 
  may 
  

   be 
  divided 
  so 
  as 
  to 
  give 
  two 
  or 
  even 
  three 
  pairs, 
  but 
  one 
  pair 
  is 
  the 
  

   normal 
  number; 
  anterior 
  pair 
  minute, 
  just 
  outside 
  the 
  bases 
  of 
  the 
  lat- 
  

   eral 
  antennae. 
  

  

  The 
  lateral 
  antennae 
  are 
  club-shaped; 
  their 
  length 
  is 
  about 
  equal 
  to 
  

   the 
  width 
  of 
  the 
  head. 
  Median 
  antenna 
  from 
  two 
  to 
  three 
  times 
  as 
  long- 
  

   as 
  the 
  lateral 
  ; 
  they 
  may 
  be 
  club-shaped 
  or 
  cylindrical. 
  

  

  The 
  buccal 
  segment 
  is 
  nearly 
  as 
  long 
  as 
  the 
  second 
  segment; 
  it 
  en- 
  

   croaches 
  slightly 
  on 
  the 
  head. 
  

  

  The 
  tentacular 
  cirri 
  are 
  like 
  the 
  lateral 
  antenna 
  1 
  , 
  but 
  a 
  little 
  shorter, 
  

   the 
  inferior 
  shorter 
  than 
  the 
  superior. 
  

  

  The 
  palpi 
  are 
  free 
  in 
  front 
  of 
  the 
  head, 
  otherwise 
  coalesced 
  ; 
  the 
  free 
  

   part 
  long, 
  outer 
  half 
  conical, 
  almost 
  pointed; 
  often 
  they 
  are 
  turned 
  

   directly 
  downward; 
  from 
  the 
  middle 
  of 
  the 
  lower 
  surface 
  a 
  small, 
  cylin- 
  

   drical 
  or 
  slightly 
  clavate 
  papilla 
  projects 
  (fig. 
  33). 
  

  

  The 
  dorsal 
  cirri 
  on 
  the 
  anterior 
  segments 
  (fig. 
  24) 
  arc 
  similar 
  to 
  the 
  

   lateral 
  antennas, 
  Further 
  back 
  they 
  may 
  be 
  club-shaped, 
  or 
  cylindrical 
  

   and 
  irregularly 
  wrinkled, 
  or 
  they 
  may 
  be 
  moniliform 
  with 
  articles 
  of 
  

   varying 
  length 
  (fig. 
  34, 
  a 
  b). 
  The 
  ventral 
  cirri 
  are 
  but 
  little 
  shorter 
  

   than 
  the 
  dorsal 
  (figs. 
  25-27), 
  very 
  stout 
  at 
  base, 
  conical, 
  acute, 
  wrinkled 
  ; 
  

   they 
  arise 
  near 
  the 
  base 
  of 
  the 
  foot 
  and 
  project 
  beyond 
  it, 
  or 
  they 
  may 
  

   he 
  turned 
  backward. 
  The 
  seta3 
  are 
  compound, 
  with 
  one, 
  or 
  rarely 
  two, 
  

  

  