﻿516 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  

  

  Mouth 
  subtermiual, 
  globose, 
  tlie 
  anterior 
  lip 
  promiuent, 
  and 
  CBSoplia- 
  

   gus 
  very 
  short, 
  intestinal 
  crura 
  not 
  extending 
  to 
  tlit^ 
  caudal 
  appendage. 
  

  

  Testes 
  two 
  at 
  each 
  side 
  near 
  the 
  ventral 
  sucker 
  and 
  behind 
  it. 
  Semi- 
  

   nal 
  vescicle 
  large, 
  ovate, 
  on 
  the 
  left 
  side; 
  vitellaria 
  voluminous 
  tubular, 
  

   mainly 
  on 
  left 
  side; 
  genital 
  aperture 
  behind 
  oral 
  sucker. 
  

  

  No. 
  4802, 
  U.S.lSr.M. 
  I 
  have 
  referred 
  a 
  lot 
  of 
  Bistoma, 
  from 
  the 
  striped 
  

   bass 
  {Roccus 
  Hneatus), 
  containing 
  seven 
  specimens, 
  to 
  this 
  species, 
  

   although 
  they 
  fail 
  to 
  agree 
  with 
  the 
  published 
  descriptions 
  of 
  the 
  species 
  

   in 
  all 
  particulars. 
  The 
  specimens 
  were 
  studied 
  only 
  in 
  their 
  alcoholic 
  

   condition, 
  and 
  since 
  the 
  very 
  considerable 
  contortions 
  of 
  the 
  body 
  which 
  

   they 
  assumed 
  and 
  retained 
  in 
  the 
  preserving 
  fluids 
  make 
  acompaiison 
  

   with 
  descriptions 
  difficult, 
  and 
  since 
  they 
  present 
  so 
  many 
  characters 
  

   which 
  belong 
  to 
  1). 
  ru/oviride, 
  I 
  have 
  thought 
  it 
  best 
  to 
  refer 
  them 
  to 
  

   that 
  species. 
  

  

  The 
  points 
  of 
  disagreement 
  are 
  : 
  The 
  pharynx 
  can 
  not 
  be 
  characterized 
  

   as 
  "elongated," 
  and 
  although 
  contiguous 
  with 
  the 
  oral 
  sucker 
  is 
  not 
  

   "partly 
  included 
  in 
  the 
  oral 
  cavity." 
  The 
  seminal 
  vescicle 
  is 
  not 
  situ- 
  

   ated 
  "next 
  the 
  anterior 
  maigin 
  of 
  the 
  acetabulum,"' 
  but 
  in 
  the 
  sectioned 
  

   specimens 
  does 
  not 
  extend 
  quite 
  so 
  far 
  forward 
  as 
  the 
  anterior 
  edge, 
  

   while 
  it 
  extended 
  posteriorly 
  some 
  distance 
  beyond 
  the 
  posterior 
  edge 
  

   of 
  the 
  ventral 
  sucker. 
  The 
  vitelline 
  glands 
  were 
  exclusively 
  on 
  the 
  left 
  

   side 
  of 
  the 
  body. 
  The 
  genital 
  aperture 
  instead 
  of 
  being 
  in 
  the 
  " 
  middle 
  

   of 
  the 
  neck," 
  was 
  immediately 
  behind 
  the 
  oral 
  aperture. 
  

  

  The 
  length 
  agrees 
  with 
  Olsson's 
  observations, 
  and 
  in 
  life 
  may 
  exceed 
  

   that, 
  in 
  which 
  case 
  it 
  would 
  come 
  within 
  the 
  limits 
  of 
  the 
  species 
  i. 
  e. 
  

   5-9 
  mm. 
  (Stossich.) 
  

  

  Found 
  in 
  intestine 
  of 
  Eoccus 
  Uneatus; 
  Woods 
  Holl, 
  Massachusetts, 
  

   September, 
  1884. 
  

  

  No 
  notes 
  were 
  made 
  at 
  the 
  time 
  of 
  collecting. 
  The 
  length 
  of 
  the 
  

   longest 
  (alcoholic) 
  specimen 
  is 
  5 
  mm., 
  that 
  of 
  tlie 
  shortest, 
  2.5; 
  diame 
  

   ter 
  of 
  largest, 
  maximum, 
  2. 
  The 
  bodies 
  are 
  variously 
  contorted, 
  but 
  

   usually 
  thickest 
  about 
  the 
  middle 
  of 
  the 
  body. 
  

  

  The 
  following 
  dimensions 
  were 
  obtained 
  from 
  measurements 
  of 
  sec- 
  

   tions 
  which 
  passed 
  somewhat 
  diagonally 
  through 
  the 
  various 
  organs, 
  

   and 
  are 
  therefore 
  not 
  exact 
  as 
  longitudinal 
  and 
  transverse 
  diameters: 
  

   Length 
  of 
  oral 
  sucker, 
  0.23 
  mm.; 
  breadth, 
  0.20; 
  length 
  of 
  pharynx, 
  

   0.14; 
  breadth, 
  0.14; 
  diameter 
  of 
  ventral 
  sucker, 
  0.53; 
  length 
  of 
  semiuid 
  

   receptacle, 
  0.02; 
  breadth, 
  0.33; 
  long 
  diameter 
  of 
  ova, 
  0.021; 
  short 
  

   diameter, 
  0,12. 
  

  

  The 
  ovary, 
  0.43 
  mm. 
  in 
  the 
  greatest 
  diameter 
  noticed 
  in 
  sections, 
  lies 
  

   behind 
  the 
  testes, 
  with 
  the 
  shell 
  gland 
  beside 
  it 
  (Plate 
  XLIII, 
  tig. 
  2). 
  

   The 
  vitellaria 
  are 
  tubular 
  and 
  lie 
  behind 
  the 
  testes 
  maiidy 
  on 
  the 
  lefc 
  

   side 
  ; 
  they 
  are 
  stained 
  red 
  in 
  my 
  carmine-stained 
  sections, 
  and 
  thus 
  differ 
  

   from 
  the 
  corresponding 
  organs 
  in 
  most 
  of 
  my 
  other 
  distoma 
  sections, 
  

   whore 
  the 
  vitellaria 
  are, 
  as 
  a 
  rule, 
  reddish-brown 
  with 
  carmine 
  stain, 
  

   liehind 
  the 
  ovary 
  the 
  body 
  is 
  to 
  a 
  great 
  extent 
  filled 
  with 
  the 
  folds 
  

  

  