﻿ON 
  A 
  NEW 
  SPHCIES 
  OF 
  THE 
  GENQS 
  HAPLOTAXIS. 
  305 
  

  

  disposition 
  in 
  the 
  body 
  is 
  similar 
  to 
  that 
  of 
  the 
  more 
  

   posteriorly 
  placed 
  excretory 
  organs 
  (cf. 
  figs. 
  3 
  and 
  7 
  with 
  

   figs. 
  16 
  — 
  24). 
  Section 
  across 
  it 
  does 
  not 
  show 
  a 
  definite 
  

   epithelium, 
  but 
  the 
  lumen 
  appears 
  to 
  traverse 
  a 
  single 
  row 
  of 
  

   cells. 
  These 
  cells, 
  or 
  rather 
  syncytium, 
  for 
  I 
  cannot 
  detect 
  

   any 
  boundary 
  to 
  the 
  component 
  cells, 
  are 
  not 
  vacuolated 
  as 
  

   are 
  the 
  nephridial 
  cells, 
  nor 
  is 
  the 
  protoplasm 
  immediately 
  

   bounding 
  the 
  lumen 
  of 
  the 
  duct 
  specially 
  granular 
  to 
  form 
  so 
  

   distinct 
  a 
  " 
  wall" 
  as 
  iu 
  the 
  case 
  of 
  the 
  nephridium. 
  Indeed, 
  

   when 
  first 
  examining 
  the 
  sections 
  1 
  mistook 
  the 
  duct 
  for 
  a 
  

   nephridium, 
  but 
  a 
  more 
  careful 
  examination 
  of 
  consecutive 
  

   sections, 
  drawn 
  with 
  a 
  camera, 
  shows 
  quite 
  without 
  any 
  doubt 
  

   that 
  this 
  tube, 
  if 
  it 
  be 
  a 
  nephridium, 
  at 
  any 
  rate 
  acts 
  as 
  a 
  

   sperm-duct. 
  In 
  the 
  right 
  duct 
  a 
  group 
  of 
  deeply 
  stained 
  

   spermatozoa 
  can 
  be 
  seen 
  entering 
  the 
  tube 
  (fig. 
  32), 
  which, 
  

   as 
  stated 
  above, 
  starts 
  from 
  the 
  ventral 
  edge 
  of 
  the 
  funnel. 
  

   In 
  the 
  lumen 
  of 
  the 
  left 
  duct 
  I 
  see 
  a 
  bunch 
  of 
  sperms 
  some 
  

   distance 
  away 
  from 
  the 
  funnel 
  ; 
  these 
  appear 
  both 
  in 
  a 
  

   portion 
  of 
  the 
  duct 
  cut 
  transversely 
  (figs. 
  25, 
  26) 
  and 
  a 
  

   little 
  further 
  along, 
  appear 
  in 
  a 
  longitudinal 
  section 
  at 
  a 
  bend 
  

   iu 
  the 
  duct 
  (fig. 
  27), 
  and 
  they 
  can 
  be 
  traced 
  through 
  several 
  

   consecutive 
  sections. 
  These 
  sperms 
  are 
  deeply 
  stained 
  by 
  

   the 
  hsemalum, 
  and 
  show 
  up 
  perfectly 
  unmistakably. 
  

  

  In 
  this 
  connection 
  it 
  is 
  interesting 
  to 
  recall 
  the 
  fact 
  that 
  

   the 
  earlier 
  students 
  of 
  Haplotaxis 
  gordioides 
  believed 
  

   that 
  the 
  nephridia 
  of 
  these 
  segments 
  acted 
  as 
  sperm-ducts, 
  

   but 
  Mr. 
  Beddard 
  was 
  the 
  first 
  to 
  identify 
  true 
  genital 
  ducts 
  

   in 
  the 
  genus 
  in 
  his 
  exauiination 
  of 
  H. 
  smithi; 
  he 
  describes 
  

   (1, 
  p. 
  391) 
  the 
  duct 
  as 
  "a 
  ciliated 
  tube 
  composed 
  of 
  a 
  single 
  

   layer 
  of 
  columnar 
  cells," 
  and 
  his 
  figure 
  6 
  (pi. 
  xxiii) 
  illustrates 
  

   this 
  statement. 
  

  

  However 
  this 
  may 
  be 
  in 
  H. 
  smithi, 
  the 
  sperm-duct 
  in 
  

   the 
  present 
  species 
  can 
  scarcely 
  be 
  distinguished 
  structurally 
  

   from 
  a 
  nephridium, 
  except 
  that 
  the 
  margin 
  of 
  the 
  canal 
  is 
  a 
  

   little 
  more 
  distinctly 
  marked 
  in 
  the 
  latter, 
  and 
  the 
  cytoplasm 
  

   of 
  the 
  cells 
  is 
  vacuolated, 
  and 
  the 
  canal 
  is 
  more 
  convoluted 
  

   than 
  in 
  the 
  sperm-duct, 
  in 
  which, 
  too, 
  cilia 
  can 
  be 
  seen 
  dis- 
  

  

  