﻿ON 
  A 
  NEW 
  SPECIES 
  OF 
  THE 
  GENUS 
  HAPLOTAXIS. 
  317 
  

  

  of 
  the 
  organ 
  as 
  a 
  collector 
  of 
  spermatozoa 
  ; 
  we 
  thus 
  have 
  a 
  

   " 
  nephromixium 
  " 
  comparable 
  to 
  the 
  arrangement 
  in 
  several 
  

   genera 
  of 
  Polychsetes. 
  Such 
  is 
  the 
  condition 
  of 
  the 
  sperm- 
  

   duct 
  in 
  Haplotaxis 
  heterogyne, 
  as 
  I 
  believe; 
  while 
  in 
  

   Octochaetus 
  multiporus 
  a 
  short 
  part 
  of 
  the 
  genital 
  duct 
  

   is 
  apparently 
  also 
  purely 
  nephridial 
  in 
  origin. 
  

  

  Third 
  stage. 
  — 
  The 
  coelomostome 
  gives 
  rise 
  to 
  its 
  own 
  

   coelomo-ductj 
  which 
  may 
  either 
  coexist 
  in 
  the 
  genital 
  segment 
  

   with 
  the 
  nephridium 
  (as 
  in 
  most 
  " 
  terricoline 
  " 
  Oligochsetes), 
  

   or 
  the 
  nephridium, 
  owing 
  perhaps 
  in 
  some 
  cases 
  to 
  the 
  small 
  

   size 
  of 
  the 
  worm, 
  disappears 
  from 
  the 
  segment 
  during 
  or 
  

   before 
  the 
  development 
  of 
  the 
  genital 
  duct 
  (as 
  in 
  " 
  limicoline" 
  

   Oligochastes 
  and 
  Pontrodrilus). 
  

  

  We 
  have, 
  then, 
  to 
  some 
  extent 
  a 
  parallel 
  series 
  of 
  phe- 
  

   nomena 
  analogous 
  to 
  those 
  described 
  with 
  so 
  much 
  care 
  by 
  

   Goodrich 
  in 
  the 
  Polychaeta, 
  from 
  which 
  it 
  would 
  appear 
  

   that 
  the 
  sperm-ducts 
  are 
  not 
  absolutely 
  homologous 
  through- 
  

   out 
  the 
  Oligochseta. 
  

  

  Bibliography. 
  

   A. 
  Haplotaxis, 
  etc. 
  

  

  1. 
  Beddaed, 
  F. 
  E.— 
  ' 
  Ann. 
  Mag. 
  Nat. 
  Hist.,' 
  1888 
  (ser. 
  6), 
  vol. 
  i, 
  p. 
  389. 
  

  

  2. 
  Beddakd, 
  F. 
  E.— 
  ' 
  Traus. 
  Roy. 
  Soc. 
  Ediub.,' 
  1889, 
  vol. 
  xxxv, 
  p. 
  629. 
  

  

  3. 
  Beddard, 
  F. 
  E.— 
  ' 
  Traus. 
  Roy. 
  Soc. 
  Ediob.,' 
  1890, 
  vol. 
  xxxvi, 
  p. 
  292 
  

  

  (Pelodrilus 
  violaceus). 
  

  

  4. 
  Forbes, 
  S. 
  A.— 
  'Bullet. 
  Illiaois 
  State 
  Lab. 
  Nat. 
  Hist.,' 
  vol. 
  iii, 
  p. 
  107. 
  

  

  5. 
  MiCHAELSEN, 
  W 
  .—' 
  Zool. 
  Jahrb. 
  (Syst.),' 
  1898, 
  vol.xii, 
  p. 
  105 
  (synonymy 
  

  

  of 
  Phreoryctes). 
  

  

  6. 
  MiCHAELSEN, 
  W.— 
  ' 
  Verb. 
  Naturw. 
  Verein.Hamb.,'1903 
  (P. 
  ignatovi)- 
  

  

  B. 
  Remarks 
  on 
  Genital 
  Ducts. 
  

  

  7. 
  Beddard. 
  — 
  ' 
  Quart. 
  Journ. 
  Micr. 
  Sci.,' 
  vol. 
  xxxiii, 
  p. 
  522. 
  

  

  8. 
  Bergh.— 
  ' 
  Zeit. 
  f. 
  wiss. 
  Zool.,' 
  vol. 
  xliv, 
  p. 
  303. 
  

  

  9. 
  Bergh.—' 
  Zeit. 
  f. 
  wiss. 
  Zool.,' 
  vol. 
  1, 
  p. 
  498. 
  

  

  10. 
  BtRGER.— 
  ' 
  Zeit. 
  f. 
  wiss. 
  Zool.,' 
  vol. 
  Ixvii, 
  p. 
  534. 
  

  

  11. 
  Goodrich.—' 
  Quart. 
  Journ. 
  Micr. 
  Sci.,' 
  vol. 
  xxxvii, 
  p. 
  477. 
  

  

  VOL. 
  48, 
  PART 
  2. 
  — 
  NEW 
  SERIES. 
  22 
  

  

  