﻿296 
  W. 
  BLAXIiAND 
  BENHAM. 
  

  

  tudinal 
  muscles 
  {Ig.) 
  of 
  tlie 
  body-wall 
  pass 
  upwards 
  so 
  as 
  to 
  form 
  tlie 
  coat 
  of 
  

   the 
  peuial 
  sac. 
  In 
  the 
  upper 
  part 
  of 
  the 
  figure, 
  at 
  A, 
  the 
  spermiducal 
  gland 
  

   has 
  been 
  cut 
  transversely 
  in 
  a 
  wider 
  region. 
  

  

  Fig. 
  8. 
  — 
  The 
  spermatheca 
  in 
  situ, 
  spili. 
  Its 
  oiifice. 
  a. 
  Its 
  muscular 
  duct. 
  

   b. 
  Glandular 
  region 
  of 
  the 
  duct. 
  c. 
  Ampulla, 
  cp. 
  Organ 
  with 
  copulatory 
  chsetse. 
  

  

  Pig. 
  9. 
  — 
  The 
  duct 
  of 
  the 
  spermatheca 
  and 
  the 
  copulatory 
  organ, 
  seen 
  in 
  

   longitudinal 
  sections. 
  The 
  details 
  of 
  structure 
  are 
  only 
  partly 
  filled 
  in. 
  The 
  

   copulatory 
  organ 
  {cp.), 
  with 
  its 
  chselse, 
  is 
  seen 
  to 
  open 
  by 
  a 
  pore 
  distinct 
  from 
  

   that 
  of 
  the 
  spermatheca. 
  a. 
  The 
  proximal 
  portion 
  of 
  the 
  muscular 
  duct, 
  a' 
  . 
  

   The 
  recurved 
  portion 
  of 
  the 
  same. 
  h. 
  The 
  point 
  at 
  which 
  a. 
  passes 
  into 
  a'. 
  

  

  Tig. 
  10. 
  — 
  The 
  point 
  h. 
  of 
  the 
  preceding 
  figure, 
  as 
  seen 
  in 
  the 
  entire 
  mounted 
  

   specimen, 
  under 
  an 
  oil 
  immersion, 
  ~. 
  The 
  region 
  a. 
  is 
  seen 
  in 
  optical 
  section, 
  

   a', 
  in 
  surface 
  view. 
  The 
  longitudinal 
  muscles 
  {Im.) 
  surrounding 
  a. 
  pass 
  away 
  

   to 
  the 
  body-wall. 
  The 
  circular 
  coat 
  {on.) 
  around 
  a', 
  ceases 
  at 
  h. 
  

  

  Fig. 
  11. 
  — 
  The 
  ventral 
  couple 
  of 
  chsetfE 
  of 
  P. 
  mauien 
  sis. 
  x 
  500. 
  

  

  Fig. 
  12. 
  — 
  View 
  of 
  the 
  right 
  side 
  of 
  the 
  genital 
  region 
  of 
  P. 
  beddardi. 
  

   d. 
  Dorsal 
  bristle, 
  d'. 
  The 
  chsetaless 
  dorsal 
  chsetal-foUicie 
  on 
  Segment 
  XIII. 
  

   V. 
  Ventral 
  chselcE. 
  ^ 
  Male 
  pore. 
  $ 
  Female 
  pore. 
  spth. 
  Spermathecal 
  pore. 
  

  

  Fig. 
  13. 
  — 
  Side 
  view 
  of 
  ventral 
  region 
  of 
  the 
  left 
  side 
  of 
  part 
  of 
  Segments 
  

   XI, 
  XII, 
  showing 
  the 
  everted 
  penial 
  sac 
  {p. 
  s.). 
  v. 
  Ventral 
  clitela) 
  of 
  

   Segment 
  XI. 
  

  

  Fig. 
  14. 
  — 
  Optical 
  section 
  of 
  ihe 
  ventral 
  portion 
  of 
  a 
  segment, 
  showing 
  the 
  

   ventral 
  couple 
  of 
  dial 
  as, 
  with 
  their 
  greatly 
  developed 
  muscles 
  {m.). 
  

  

  Fig. 
  11a.' 
  — 
  The 
  spermatheca 
  in 
  situ, 
  seen 
  from 
  the 
  side. 
  spth. 
  Spermathecal 
  

   pore. 
  a. 
  Muscular 
  duct. 
  c. 
  Ampulla. 
  

  

  Fig. 
  15. 
  — 
  A 
  transverse 
  section 
  through 
  the 
  muscular 
  duct 
  of 
  the 
  sperma- 
  

   theca, 
  a 
  short 
  distance 
  from 
  the 
  pore. 
  It 
  is 
  provided 
  with 
  both 
  circular 
  and 
  

   longitudinal 
  muscles, 
  the 
  former 
  of 
  considerable 
  thickness; 
  in 
  the 
  latter 
  the 
  

   round 
  nuclei 
  of 
  muscle-cells 
  (?) 
  are 
  seen 
  betM'een 
  the 
  cut 
  fibres 
  and 
  the 
  peri- 
  

   toneum 
  {c.e.). 
  

  

  Fig. 
  1G. 
  — 
  The 
  male 
  efferent 
  apparatus; 
  the 
  figure 
  is 
  constructed 
  from 
  

   sketches 
  of 
  the 
  isolated 
  organ 
  as 
  seen 
  as 
  an 
  opaque 
  object 
  and 
  in 
  a 
  glycerine 
  

   preparation. 
  The 
  atrial 
  sac 
  is 
  represented 
  as 
  transparent 
  so 
  as 
  to 
  exhibit 
  the 
  

   atrium 
  within, 
  and 
  the 
  penial 
  sac 
  also 
  allows 
  the 
  contained 
  penis 
  to 
  be 
  seen. 
  

   A 
  fan-shaped 
  bundle 
  of 
  muscle 
  {m. 
  w.), 
  springing 
  from 
  the 
  body-wall, 
  enwraps 
  

   the 
  atrial 
  sac, 
  giving 
  rise 
  to 
  its 
  circular 
  coat 
  of 
  muscles. 
  

  

  Fig. 
  17. 
  — 
  The 
  penial 
  sac 
  and 
  penis 
  in 
  optical 
  section, 
  as 
  seen 
  when 
  isolated 
  

   in 
  a 
  glycerine 
  preparation. 
  The 
  lower 
  end 
  of 
  the 
  atrium 
  («/.) 
  is 
  seen 
  in 
  the 
  

   atrial 
  sac 
  {a(s.), 
  to 
  the 
  inner 
  surface 
  of 
  which 
  it 
  is 
  connected 
  by 
  radiating 
  

   muscle-fibres 
  {r. 
  m.) 
  ; 
  it 
  is 
  also 
  accompanied 
  by 
  longitudinal 
  fibres. 
  The 
  penis, 
  

   in 
  comparison 
  with 
  the 
  preceding 
  species 
  (fig. 
  5), 
  is 
  seen 
  to 
  be 
  of 
  much 
  

  

  