﻿EXPLANATION 
  OF 
  PLATES 
  

  

  All 
  figures 
  were 
  made 
  by 
  the 
  writer 
  directly 
  from 
  dissections 
  or 
  

   specimens. 
  

  

  Plate 
  20 
  

  

  Echiurus 
  echiurus 
  alaskanus, 
  new 
  subspecies 
  

  

  1, 
  Dorsal 
  view 
  of 
  anatomy 
  of 
  anterior 
  portion 
  of 
  body, 
  X 
  5. 
  Body 
  wall 
  is 
  indi- 
  

  

  cated 
  only 
  in 
  pharyngeal 
  region. 
  Junction 
  of 
  diaphragm 
  to 
  body 
  wall 
  is 
  

   indicated 
  by 
  dashes 
  for 
  dorsal 
  half 
  and 
  dots 
  for 
  ventral 
  half. 
  Coiled 
  loops 
  

   of 
  esophagus 
  are 
  shown 
  emerging 
  from 
  posterior 
  opening 
  of 
  diaphragm, 
  

   below 
  the 
  interbasal 
  muscle. 
  Lines 
  radiating 
  from 
  pharynx 
  are 
  the 
  muscu- 
  

   lar 
  frenula. 
  The 
  peripharyngeal 
  coelom 
  is 
  shaded. 
  

  

  2, 
  Anal 
  bristle 
  from 
  posterior 
  ring, 
  7.5 
  mm. 
  long. 
  

  

  3, 
  Anal 
  bristle 
  from 
  anterior 
  ring, 
  8 
  mm. 
  long. 
  

  

  4, 
  Diagram 
  of 
  the 
  diaphragm 
  (ventral 
  half 
  dotted) 
  showing 
  the 
  posterodorsal 
  

  

  opening. 
  The 
  esophagus 
  is 
  omitted 
  except 
  where 
  it 
  pierces 
  the 
  right 
  wall 
  

   and 
  becomes 
  the 
  gizzard. 
  The 
  edges 
  that 
  are 
  attached 
  to 
  body 
  wall 
  and 
  

   ventral 
  mesenteries 
  are 
  dashes. 
  

  

  5, 
  Diagram 
  of 
  a 
  section 
  through 
  diaphragm 
  showing 
  how 
  its 
  lower 
  border 
  merges 
  

  

  with 
  the 
  ventral 
  mesenteries. 
  

  

  B^B*, 
  dorsal, 
  ring, 
  neurointestinal, 
  and 
  ventral 
  blood 
  vessels, 
  respectively," 
  

   C, 
  stomach; 
  CG, 
  ciliated 
  groove; 
  D, 
  diaphragm; 
  G, 
  gizzard; 
  MD, 
  dorsa 
  

   mesenteries 
  of 
  esophagus; 
  MV, 
  ventral 
  mesenteries 
  of 
  esophagus 
  (fig. 
  5); 
  

   A^, 
  nephridium; 
  NC, 
  nerve 
  cord; 
  0, 
  esophagus, 
  indicated 
  by 
  arrows, 
  ventral 
  

   mesentery 
  omitted, 
  dorsal 
  inesenteries 
  shown 
  as 
  lighter 
  lines; 
  P, 
  pharynx; 
  

   Si, 
  anterior 
  end 
  of 
  siphon; 
  X, 
  perivisceral 
  coelom 
  (Sg. 
  4); 
  A^^, 
  peripharyngeal 
  

   coelom. 
  

  

  Plate 
  21 
  

  

  Listriolohus 
  pelodes, 
  new 
  species 
  

  

  1, 
  Ventral 
  view 
  of 
  a 
  large 
  specimen 
  from 
  Monterey 
  Bay, 
  Calif., 
  X 
  l}4. 
  

  

  2, 
  Same 
  specimen, 
  X 
  5, 
  ventral 
  view 
  of 
  anterior 
  end 
  showing 
  nerve 
  loop 
  in 
  pro- 
  

  

  boscis, 
  a 
  section 
  of 
  which 
  has 
  been 
  removed. 
  

  

  4, 
  Small 
  phase 
  before 
  muscle 
  bands 
  are 
  evident, 
  natural 
  size. 
  

  

  4c, 
  Side 
  view 
  of 
  anterior 
  end 
  of 
  a 
  living 
  specimen, 
  X 
  3. 
  

  

  46, 
  A 
  female, 
  X 
  3, 
  showing 
  nephridia 
  and 
  fecal 
  pellets. 
  At 
  this 
  size 
  the 
  muscle 
  

   bands 
  are 
  not 
  apparent 
  unless 
  the 
  specimen 
  is 
  stronglj^ 
  contracted. 
  Out- 
  

   line 
  from 
  living 
  animal. 
  

  

  Ocheiostoma 
  octomyotum, 
  new 
  species 
  

  

  3, 
  Ventral 
  view 
  of 
  type 
  specimen 
  from 
  Newport 
  Bay, 
  Calif., 
  natural 
  size. 
  A 
  

  

  specimen 
  from 
  Cabrillo 
  Beach, 
  near 
  San 
  Pedro, 
  95 
  mm. 
  long, 
  has 
  a 
  pro- 
  

   boscis 
  93 
  mm. 
  

  

  Plate 
  22 
  

  

  Listriolohus 
  pelodes, 
  new 
  species 
  

  

  Type 
  specimen, 
  X 
  7, 
  dissected 
  to 
  show 
  organs 
  of 
  anterior 
  portion 
  of 
  the 
  body; 
  

  

  the 
  alimentary 
  canal 
  is 
  drawn 
  to 
  the 
  right 
  of 
  its 
  natural 
  position. 
  

   B', 
  dorsal 
  blood 
  vessel; 
  B^, 
  ring 
  vessel; 
  B^, 
  neurointestinal 
  connective; 
  B*, 
  ventral 
  

   vessel; 
  C, 
  stomach; 
  CG, 
  ciliated 
  groove 
  of 
  intestine; 
  G, 
  gizzard; 
  I, 
  intestine; 
  

   286 
  

  

  