﻿412 
  PROCEEDINGS 
  OE 
  THE 
  NATIONAL 
  MUSEUM. 
  vol.44. 
  

  

  extraordinarily 
  variable 
  in 
  shape; 
  the 
  chitinous 
  part 
  of 
  the 
  papilla 
  

   is 
  usually 
  crescentic 
  and 
  provided 
  with 
  a 
  point 
  projecting 
  forward, 
  

   but 
  in 
  some 
  individuals 
  the 
  convexity 
  of 
  the 
  crescent 
  extends 
  laterally, 
  

   or 
  even 
  backward. 
  Double 
  crescents 
  and 
  rings 
  of 
  cliitinous 
  material 
  

   are 
  sometimes 
  found 
  upon 
  the 
  attaching 
  papillae. 
  These 
  holdfasts 
  

   therefore 
  appear 
  to 
  be 
  more 
  variable 
  than 
  in 
  other 
  varieties 
  of 
  the 
  

   species. 
  

  

  There 
  are 
  16 
  tentacles. 
  Dark-colored, 
  recurved 
  hooks 
  are 
  scat- 
  

   tered 
  over 
  a 
  broad 
  zone 
  separated 
  from 
  the 
  tentacles 
  by 
  a 
  distance 
  

   about 
  equal 
  to 
  its 
  width. 
  These 
  hooks, 
  though 
  not 
  regularly 
  dis- 
  

   tributed, 
  may 
  be 
  considered 
  as 
  forming 
  eight 
  or 
  nine 
  irregular 
  rows. 
  

  

  This 
  variety 
  differs 
  internally 
  from 
  others 
  in 
  two 
  or 
  three 
  notice- 
  

   able 
  respects. 
  The 
  posterior 
  attachment 
  of 
  the 
  dorsal 
  retractor 
  

   muscle 
  shows 
  a 
  tendency 
  to 
  break 
  into 
  several 
  distinct 
  strands, 
  a 
  

   fact 
  which 
  is 
  due 
  to 
  the 
  shape 
  of 
  the 
  body 
  wall 
  at 
  the 
  point 
  where 
  

   attachment 
  is 
  made. 
  The 
  second 
  peculiarity 
  is 
  the 
  shape 
  of 
  the 
  

   eggs, 
  which 
  are 
  ovoid, 
  translucent, 
  and 
  about 
  103 
  by 
  124 
  in 
  diam- 
  

   eter. 
  The 
  yolk 
  membrane, 
  or 
  zona 
  radiata, 
  is 
  of 
  medium 
  thickness 
  

   (3.8 
  or 
  4) 
  and 
  has 
  distinct 
  pore 
  canals. 
  Finally 
  the 
  crescentic 
  

   nephrostome 
  joins 
  the 
  nephridium 
  by 
  a 
  somewhat 
  slender 
  neck. 
  

  

  PHASCOLION 
  STROMBI 
  var. 
  CANADENSIS, 
  new 
  variety. 
  

  

  Ba}^ 
  of 
  Fundy. 
  In 
  shells 
  of 
  Dentalium 
  and 
  of 
  gasteropods. 
  

  

  Stations 
  43-46, 
  lat. 
  43° 
  06' 
  N.; 
  long. 
  65° 
  06' 
  W.; 
  90 
  fathoms, 
  fine 
  

   sandy 
  mud. 
  

  

  Station 
  47, 
  lat. 
  43° 
  10' 
  N.; 
  long. 
  65° 
  12^' 
  W.; 
  SE. 
  i 
  S. 
  from 
  Cape 
  

   Sable 
  about 
  22 
  miles, 
  59 
  fathoms, 
  pebbles 
  and 
  sand. 
  In 
  tubes 
  of 
  

   Pectinaria, 
  tubes 
  of 
  cement, 
  gasteropod 
  shells. 
  

  

  Station 
  55, 
  mouth. 
  of 
  Bedford 
  Basin, 
  33 
  fathoms, 
  mud; 
  in 
  Pec- 
  

   tinaria 
  tubes. 
  

  

  Type.— 
  Ca,t. 
  No. 
  8582, 
  U.S.N.M. 
  

  

  Stations 
  82-83, 
  lat. 
  44° 
  22' 
  N.; 
  long. 
  65° 
  28' 
  W.; 
  Chebiicto 
  

   Light, 
  N. 
  ^ 
  E. 
  9 
  miles, 
  57 
  fathoms, 
  mud 
  and 
  sand. 
  

  

  Station 
  103, 
  lat. 
  44° 
  02' 
  N.; 
  long. 
  63° 
  20' 
  W.; 
  29f 
  miles 
  south 
  

   of 
  Chebucto 
  Head, 
  110 
  fathoms, 
  fine 
  sand 
  and 
  mud. 
  

  

  Stations 
  106-108, 
  near 
  last. 
  In 
  HyalinoRcia 
  tubes. 
  

  

  Station 
  2506, 
  lat. 
  44° 
  26' 
  00" 
  N.; 
  long. 
  62° 
  10' 
  00" 
  W.; 
  127 
  

   fathoms, 
  dark-brown 
  mud. 
  

  

  Station 
  2697, 
  lat. 
  47° 
  40' 
  00" 
  N.; 
  long. 
  47° 
  35' 
  30" 
  W. 
  ; 
  206 
  

   fathoms, 
  green 
  mud, 
  black 
  specks. 
  

  

  In 
  certain 
  localities 
  off 
  the 
  coast 
  of 
  Nova 
  Scotia 
  a 
  form 
  of 
  Ph. 
  

   stromhi 
  is 
  found 
  with 
  a 
  remarkably 
  short 
  introvert, 
  with 
  a 
  smooth, 
  

   lustrous 
  skin 
  in 
  the 
  region 
  of 
  the 
  holdfasts, 
  and 
  a 
  tendency 
  of 
  the 
  

   dorsal 
  retractor 
  to 
  be 
  divided 
  at 
  the 
  posterior 
  attachment 
  into 
  two 
  

   roots. 
  These 
  characters 
  during 
  the 
  earlier 
  part 
  of 
  my 
  study 
  appeared 
  

   to 
  be 
  of 
  specific 
  importance, 
  but 
  the 
  examination 
  of 
  many 
  speci- 
  

  

  