﻿NO. 
  1959. 
  SIPUNCULID8 
  OF 
  EASTERN 
  NORTE 
  AMERICA— 
  GEROULD. 
  403 
  

  

  SYNOPSIS 
  OF 
  SPECIES 
  AND 
  VARIETIES 
  OF 
  PHASCOLION. 
  

  

  Posterior 
  attachment 
  

   of 
  dorsal 
  retractor 
  

   usually 
  undi 
  vid 
  ed 
  , 
  

   tiiat 
  of 
  ventral 
  

   with 
  two 
  roots. 
  

  

  Phascolion 
  stromhi 
  

   (Montagu), 
  16-26 
  

   tentacles. 
  

  

  In 
  trovert 
  longer 
  

   than 
  the 
  

   trunk. 
  

  

  (a) 
  Common 
  form, 
  orange- 
  

   brown 
  or 
  yellowish- 
  

   brown. 
  Range 
  from 
  

   Labrador 
  southward 
  to 
  

   40° 
  N 
  . 
  lat 
  Y&r.fusca. 
  

  

  (b) 
  Dark-colored, 
  with' 
  

   thick 
  skin, 
  sharp 
  hold- 
  

   fasts 
  var. 
  tubicola. 
  

  

  (c) 
  Small, 
  white 
  form 
  in 
  

   gasteropod 
  shells, 
  com- 
  

   mon 
  in 
  region 
  of 
  Woods 
  

   Hole, 
  Mass... 
  var. 
  alba. 
  

  

  (d) 
  Deep-sea 
  form 
  with 
  

   short, 
  thin-walled 
  trunk, 
  

   large 
  opaque, 
  ovoid 
  eggs 
  

   var. 
  hyalina. 
  

  

  Introvert 
  of 
  about 
  the 
  same 
  length 
  as 
  trunk, 
  

   in 
  shells 
  of 
  Protula 
  and 
  Dentalium. 
  Off 
  

   Cape 
  Cod, 
  and 
  near 
  the 
  40th 
  parallel. 
  

   Elongated, 
  smooth; 
  16 
  tentacles. 
  Eggs 
  

  

  ovoid 
  (e) 
  var. 
  gracilis. 
  

  

  Introvert 
  shorter 
  than 
  the 
  trunk; 
  dorsal 
  

   retractor 
  in 
  some 
  individuals 
  is 
  divided 
  

   at 
  the 
  base. 
  Blends, 
  and 
  probably 
  

   freely 
  interbreeds 
  with 
  var. 
  fusco: 
  

  

  (/) 
  var. 
  canadensis. 
  

  

  Introvert 
  two-thirds 
  the 
  length 
  of 
  the 
  

   trunk; 
  papillae 
  of 
  anterior 
  and 
  middle 
  

   part 
  of 
  the 
  trimk 
  provided 
  with 
  chitinous 
  

   denticles, 
  pointing 
  forward. 
  Chitinous 
  

   cap 
  of 
  papillae 
  at 
  posterior 
  end 
  of 
  trunk 
  

   oval. 
  Off 
  Newfoundland 
  (Prince 
  of 
  

   Monaco, 
  1887), 
  1,267 
  meters. 
  Off 
  Cape 
  

   Finisterre, 
  1,674 
  meters. 
  

   Dorsal 
  retractors, 
  as 
  well 
  as 
  ventral, 
  probably 
  

  

  with 
  two 
  roots, 
  introvert 
  longer 
  than 
  the 
  trunk 
  

  

  and, 
  like 
  the 
  posterior 
  end 
  of 
  the 
  trunk, 
  

  

  smooth. 
  Constructs 
  a 
  tube 
  with 
  an 
  additional 
  

  

  slender 
  sheath 
  for 
  the 
  introvert. 
  

  

  Phascolion 
  

   Sluiter. 
  

  

  alberti 
  

  

  Phascolion 
  strombi 
  var. 
  Isevis. 
  Off 
  

   coast 
  of 
  Massachusetts, 
  54 
  fathoms. 
  

  

  PHASCOLION 
  STROMBI 
  (Montagu). 
  

   Sipunculits 
  strombus 
  G. 
  Montagu, 
  Trans. 
  Linnean 
  Soc. 
  London, 
  vol. 
  7, 
  1804, 
  

  

  pp. 
  74-76. 
  

   Siphunculus 
  dentalii 
  Geay, 
  Spicilegia 
  Zoologica, 
  London, 
  1828, 
  p. 
  8. 
  

   Sipunculits 
  bemhardus 
  Forbes, 
  A 
  History 
  of 
  British 
  Starfishes, 
  London, 
  1841, 
  

  

  pp. 
  251-253. 
  

   Sipunculus 
  (Phascolosoma) 
  concharum 
  Orsted, 
  De 
  regionibus 
  marinis, 
  Diss. 
  phil. 
  

  

  Haun., 
  Haunise, 
  1844, 
  p. 
  80, 
  and 
  Kr0yer's 
  naturh. 
  Tidskrift, 
  p. 
  419. 
  

   Phascolosoma 
  strombi 
  Diesing, 
  Systema 
  Helminthum. 
  Vindob., 
  vol. 
  2, 
  1851, 
  p. 
  

  

  Phascolosomum 
  dentalii 
  Diesing, 
  Systema 
  Helminthum. 
  Vindob., 
  vol. 
  2, 
  

   pp. 
  64-65. 
  

  

  1851, 
  

  

  