﻿ECHIUROID 
  WORMS 
  OF 
  NORTH 
  PACIFIC 
  — 
  FISHER 
  2G9 
  

  

  tho 
  spiral 
  lips) 
  without 
  lodc:iii<]: 
  in 
  the 
  extornal 
  groove. 
  Sperm 
  is 
  col- 
  

   lected 
  ill 
  the 
  outer 
  groove 
  of 
  male 
  collecting 
  threads, 
  fed 
  into 
  the 
  

   iimer 
  groove, 
  and 
  carried 
  to 
  the 
  storage 
  organ." 
  " 
  

  

  There 
  is 
  no 
  permanent 
  gonad. 
  "Sex 
  cells 
  in 
  all 
  stages 
  of 
  develop- 
  

   ment, 
  from 
  very 
  immature 
  ones 
  to 
  those 
  wliich 
  appear 
  to 
  be 
  fully 
  

   mature 
  ore 
  found 
  in 
  the 
  coelomic 
  fluid 
  at 
  all 
  times 
  of 
  the 
  year. 
  In 
  

   the 
  case 
  of 
  the 
  male, 
  the 
  apparently 
  mature, 
  free-floating 
  sex 
  cells 
  are 
  

   known 
  to 
  be 
  functional." 
  (MacGinitie, 
  1935c, 
  p. 
  485.) 
  "I 
  have 
  

   examined 
  a 
  male 
  collected 
  in 
  winter 
  as 
  well 
  as 
  several 
  specimens 
  of 
  

   both 
  sexes 
  collected 
  in 
  the 
  summer 
  and 
  in 
  these 
  I 
  could 
  establish 
  

   neither 
  qualitative 
  nor 
  quantitative 
  dilFerenccs 
  in 
  the 
  sex 
  cells 
  at 
  tho 
  

   two 
  seasons. 
  Furthermore, 
  in 
  neither 
  season 
  did 
  I 
  find 
  mitotic 
  fig- 
  

   ures 
  in 
  any 
  area 
  of 
  the 
  peritoneum 
  nor 
  could 
  I 
  establish 
  any 
  evidence 
  

   of 
  division 
  by 
  any 
  of 
  the 
  cells 
  which 
  were 
  free 
  in 
  the 
  coelom. 
  Thus 
  

   there 
  is 
  no 
  evidence 
  in 
  regard 
  to 
  the 
  origin 
  of 
  the 
  sex 
  cells 
  in 
  Urechis." 
  

   (Xewby, 
  1940, 
  p. 
  7.) 
  

  

  MacGinitie 
  (1935a, 
  p. 
  342) 
  estimates 
  that 
  there 
  are 
  nearly 
  3 
  billion 
  

   sperms 
  present 
  in 
  the 
  nephridia 
  of 
  an 
  average-sized 
  male 
  and 
  over 
  6 
  

   million 
  eggs 
  in 
  an 
  equal-sized 
  female. 
  The 
  eggs 
  are 
  0.115 
  to 
  0.12 
  mm. 
  

   in 
  diameter 
  according 
  to 
  MacGinitie 
  (southern 
  California 
  specimens). 
  

   C. 
  V. 
  Taylor 
  measured 
  303 
  from 
  the 
  Monterey 
  Bay 
  region 
  and 
  found 
  

   them 
  to 
  range 
  between 
  0.123 
  and 
  0.144 
  mm. 
  in 
  diameter.^* 
  The 
  egg 
  is 
  

   ver}' 
  clear, 
  with 
  a 
  large 
  nucleus, 
  containing 
  a 
  nucleolus 
  0.012 
  to 
  0.016 
  

   mm. 
  in 
  diameter. 
  

  

  The 
  anal 
  vesicles, 
  contracted, 
  have 
  a 
  cauliflower 
  surface 
  beset 
  with 
  

   minute 
  ciliated 
  funnels. 
  They 
  empty, 
  vcntrally, 
  into 
  the 
  posterior 
  

   part 
  of 
  the 
  cloaca. 
  

  

  In 
  addition 
  to 
  abundant 
  sex 
  cells, 
  the 
  coelomic 
  fluid 
  is 
  filled 
  with 
  

   nucleated 
  red 
  or 
  brown 
  blood 
  corpuscles 
  subcircular 
  in 
  shape 
  and 
  up- 
  

   ward 
  of 
  0.035 
  mm. 
  in 
  diameter, 
  together 
  with 
  very 
  numerous 
  amoe- 
  

   i>oid 
  cells, 
  yellowi.sh 
  when 
  aggregated. 
  "The 
  color 
  of 
  the 
  blood 
  

   varies 
  from 
  the 
  i)urest 
  oxyhemoglobin 
  red 
  to 
  the 
  darkest 
  brown-black 
  

   or 
  a 
  blacidike 
  Chinese 
  ink, 
  even 
  after 
  complete 
  saturation 
  with 
  o.xygen. 
  

   The 
  red 
  color 
  is 
  due 
  to 
  liemoglobin 
  homogeneously 
  distributed 
  within 
  

   tho 
  blood 
  cells. 
  Wiieiiever 
  the 
  color 
  is 
  brown, 
  besides 
  this 
  hemoglol)in 
  

   there 
  is 
  another 
  granular 
  pigment 
  of 
  brown 
  color 
  within 
  the 
  cells 
  

   wliich 
  will 
  be 
  proved 
  to 
  be 
  hematin. 
  Red 
  blood 
  was 
  encountered 
  in 
  

   some 
  few 
  of 
  the 
  smallest 
  indiviihials 
  and 
  in 
  some 
  of 
  the 
  very 
  largest 
  

   sex-mature 
  females. 
  The 
  majority 
  of 
  the 
  individuals, 
  of 
  medium 
  size, 
  

   contained 
  brown 
  or 
  brown-bhick 
  blood." 
  (Baumberger 
  and 
  

   Miehaelis, 
  1931, 
  p. 
  417.) 
  

  

  »» 
  Mnrfilnltlp, 
  llO.'*, 
  p. 
  340. 
  A 
  carrful 
  pnpcr 
  bawd 
  upon 
  observation 
  of 
  living 
  material 
  and 
  tho 
  only 
  one 
  

   dcsrrlMnit 
  tho 
  l)»>hii%ior 
  of 
  the 
  nophrldlnl 
  nppcndoKos. 
  

   » 
  Pbyslologlcal 
  Zoology, 
  vol. 
  4, 
  p. 
  430, 
  1031. 
  

  

  