﻿SIPUNCVLIDS 
  OF 
  EASTERN 
  NORTH 
  AMERICA— 
  OEROULD. 
  387. 
  

  

  There 
  are 
  22-24 
  simple 
  tentacles 
  in 
  the 
  specimens 
  which 
  I 
  have 
  

   examined, 
  produced 
  by 
  the 
  slight 
  modification 
  of 
  a 
  tentacular 
  fold. 
  

   Th^el 
  (1905) 
  finds, 
  among 
  the 
  many 
  specimens 
  from 
  the 
  northern 
  

   and 
  Arctic 
  regions 
  that 
  he 
  has 
  examined, 
  from 
  16 
  to 
  40 
  tentacles. 
  

   Each 
  has 
  the 
  usual 
  longitudinal 
  furrow 
  on 
  the 
  oral 
  surface. 
  A 
  

   simple 
  nuchal 
  organ 
  consisting 
  of 
  a 
  pair 
  of 
  elevations 
  lies 
  in 
  the 
  mid- 
  

   dorsal 
  interruption 
  of 
  the 
  tentacles. 
  

  

  The 
  longitudinal 
  muscles 
  

   form 
  a 
  continuous 
  layer. 
  

   The 
  two 
  retractors 
  (fig. 
  1) 
  

   have 
  their 
  origin 
  in 
  the 
  

   nuddle 
  third 
  of 
  the 
  body. 
  

   A 
  pair 
  of 
  prominent 
  gonads 
  

   were 
  found 
  attached 
  to 
  their 
  

   bases. 
  The 
  nephridia 
  are 
  

   small 
  and 
  hang 
  free. 
  The 
  

   brain 
  is 
  not 
  distinctly 
  bi- 
  

   lobed, 
  and 
  is 
  without 
  visible 
  

   eye-spots. 
  There 
  is 
  a 
  well- 
  

   marked 
  cerebral 
  organ. 
  The 
  

   alimentary 
  tube 
  has 
  numer- 
  

   ous 
  coils. 
  The 
  esophagus 
  is 
  

   attached 
  to 
  each 
  of 
  the 
  re- 
  

   tractor 
  muscles 
  by 
  a 
  perito- 
  

   neal 
  membrane 
  containing 
  

   muscle 
  fibers. 
  The 
  intestinal 
  

   coil 
  hangs 
  free 
  behind, 
  but 
  

   is 
  held 
  at 
  the 
  anterior 
  end 
  

   by 
  two 
  muscle 
  strands, 
  one 
  

   attached 
  to 
  the 
  junction 
  be- 
  

   tween 
  the 
  esophagus 
  and 
  

   descending 
  spire, 
  united 
  to 
  

   the 
  body 
  wall 
  on 
  the 
  left; 
  

   and 
  one 
  attached 
  to 
  the 
  

   third 
  coil 
  and 
  to 
  the 
  right 
  side 
  of 
  the 
  body 
  wall. 
  There 
  is 
  no 
  spindle 
  

   muscle, 
  but 
  a 
  transverse 
  sheet 
  of 
  muscle 
  holds 
  the 
  short 
  rectum 
  to 
  

   the 
  wall 
  of 
  the 
  bod}^. 
  There 
  is 
  a 
  simple 
  Polian 
  tube. 
  

  

  PHASCOLOSOMA 
  EREMITA 
  (Sars) 
  var. 
  SCABRA, 
  new 
  variety. 
  

  

  Specimens, 
  which 
  may 
  be 
  designated 
  as 
  representatives 
  of 
  a 
  new 
  

   variety, 
  scabra, 
  were 
  dredged 
  with 
  Phascolion 
  strombi 
  and 
  a 
  species 
  

   of 
  Dentalium 
  probably 
  oft' 
  Cashes 
  Ledge 
  in 
  the 
  Gulf 
  of 
  Maine 
  in 
  

   1873. 
  The 
  shape 
  of 
  the 
  contracted 
  specimens 
  indicates 
  that 
  they 
  

   may 
  have 
  been 
  taken, 
  like 
  the 
  Phascolions, 
  from 
  cast 
  moUusk 
  shells. 
  

  

  Type.— 
  C'dt. 
  No. 
  8396, 
  U.S.N.M. 
  

  

  Fig. 
  1.— 
  Dissection 
  showing 
  internal 
  structure 
  of 
  

  

  PHASCOLOSOMA 
  EREMITA. 
  X 
  4, 
  an, 
  ANUS; 
  gU, 
  CERE- 
  

   BRAL 
  ganglion; 
  go, 
  reproductive 
  organs; 
  nph, 
  ne- 
  

   pheidium; 
  tb. 
  P, 
  Polian 
  tubule. 
  

  

  