﻿Eeproductive 
  organs 
  of 
  Taenia 
  pisiformis. 
  363 
  

  

  yagina. 
  Lönnbeeg 
  (1892) 
  in 
  Diplogonoporus 
  halaenopterae 
  and 
  Stiles 
  & 
  

   Hassall 
  (1893) 
  in 
  Moniesia 
  planissima 
  describe 
  this 
  epithelium 
  as 
  a 
  

   homogeneous 
  or 
  protoplasmic 
  layer 
  containing 
  nuclei. 
  In 
  Taenia 
  

   pisiformis 
  on 
  the 
  contrarj^ 
  the 
  epithelium 
  as 
  such 
  does 
  not 
  persist. 
  

   Beaun 
  (1894 
  — 
  1900, 
  p. 
  1426) 
  describes 
  the 
  end 
  of 
  the 
  vagina 
  as 
  

   lined 
  by 
  "die 
  das 
  Genitalatrium 
  auskleidende 
  Cuticula" 
  and 
  a 
  similar 
  

   account 
  has 
  been 
  given 
  by 
  several 
  other 
  writers. 
  

  

  In 
  Taenia 
  pisiformis 
  the 
  cuticula 
  lining 
  the 
  vagina 
  is 
  a 
  con- 
  

   tinuation 
  of 
  that 
  of 
  the 
  genital 
  atrium, 
  but 
  differs 
  from 
  most 
  of 
  the 
  

   latter 
  in 
  being 
  ciliated, 
  the 
  cilia 
  extending 
  into 
  the 
  atrium 
  a 
  short 
  

   distance 
  beyond 
  the 
  opening 
  of 
  the 
  former. 
  

  

  The 
  seminal 
  receptacle 
  is 
  merely 
  the 
  enlarged 
  end 
  of 
  the 
  

   vagina^) 
  and 
  develops 
  similarly 
  to 
  the 
  latter. 
  According 
  to 
  Balss 
  

   (1908) 
  in 
  Anoplocephala 
  magna 
  the 
  seminal 
  receptacle 
  retains 
  its 
  

   original 
  epithelium, 
  which 
  undergoes 
  extreme 
  distension 
  when 
  the 
  

   organ 
  is 
  filled 
  with 
  sperms. 
  Meyner 
  (1895) 
  in 
  Taenia 
  conferta, 
  and 
  

   Eelanger 
  (1890) 
  in 
  Taenia 
  echinococcus 
  , 
  etc. 
  also 
  describe 
  an 
  epi- 
  

   thelium 
  in 
  the 
  seminal 
  receptacle, 
  while 
  the 
  former 
  author 
  in 
  Taenia 
  

   mucronata, 
  Leuckart 
  (1886) 
  in 
  Bothriocephalus 
  latus, 
  Go 
  ugh 
  (1911) 
  

   in 
  AvitelUna, 
  etc. 
  deny 
  its 
  presence, 
  at 
  least 
  in 
  the 
  adult 
  organ. 
  

   LuNGwiTz 
  (1895) 
  describes 
  the 
  seminal 
  receptacle 
  of 
  Taenia 
  ovilla 
  

   as 
  lined 
  by 
  a 
  layer 
  of 
  cuboidal 
  cells 
  near 
  the 
  vagina, 
  which 
  dis- 
  

   appears 
  distal 
  to 
  the 
  latter 
  where 
  the 
  wall 
  is 
  distended 
  by 
  masses 
  of 
  

   sperms. 
  Thus 
  not 
  alone 
  in 
  different 
  species, 
  but 
  even 
  in 
  different 
  

   parts 
  of 
  the 
  same 
  organ 
  in 
  the 
  same 
  worm, 
  the 
  epithelium 
  may 
  

   undergo 
  a 
  different 
  fate. 
  My 
  own 
  observations 
  show 
  that 
  in 
  Taenia 
  

   jjisiformis 
  the 
  epithelium 
  persists 
  as 
  a 
  thin 
  layer 
  of 
  protoplasm 
  

   containing 
  scattered 
  nuclei 
  (Fig. 
  21). 
  

  

  The 
  vas 
  deferens 
  and 
  penis 
  ^) 
  undergo 
  a 
  development 
  

   similar 
  in 
  general 
  so 
  that 
  of 
  the 
  vagina. 
  There 
  are 
  present 
  here 
  

   the 
  same 
  outer 
  and 
  inner 
  layers 
  of 
  cells 
  separated 
  by 
  a 
  basement 
  

   membrane, 
  while 
  a 
  circular 
  ^) 
  layer 
  of 
  scattered 
  muscle 
  fibres 
  develops 
  

   just 
  external 
  to 
  the 
  latter 
  (Figs. 
  10 
  and 
  28). 
  The 
  development 
  of 
  the 
  

   two 
  latter 
  structures 
  is, 
  as 
  described 
  for 
  the 
  vagina, 
  direct 
  from 
  

  

  1) 
  Contra 
  GouGH, 
  who 
  finds 
  this 
  organ 
  arising 
  "out 
  of 
  a 
  clump 
  of 
  

   cells 
  which 
  already 
  show 
  the 
  final 
  shape 
  of 
  the 
  organ" 
  (1911, 
  p. 
  370). 
  

  

  2) 
  I 
  apply 
  the 
  term 
  "penis" 
  to 
  that 
  part 
  of 
  the 
  duct 
  enclosed 
  within 
  

   a 
  special 
  muscular 
  sack 
  or 
  penis 
  sheath. 
  

  

  3) 
  In 
  the 
  penis 
  a 
  layer 
  of 
  longitudinal 
  fibres 
  develops 
  external 
  to 
  

   this 
  layer. 
  

  

  