﻿TREMATODE 
  PAEASITES 
  OF 
  FISHES— 
  LINTON. 
  525 
  

  

  anterior 
  end, 
  body 
  otherwise 
  flattened 
  but 
  quite 
  thick. 
  The 
  color 
  at 
  

   first 
  was 
  purplish 
  merging- 
  into 
  orange-red. 
  When 
  placed 
  in 
  sea-water 
  

   it 
  voided 
  enough 
  dark-colored 
  material 
  to 
  color 
  the 
  water 
  in 
  a 
  small 
  

   dish 
  dark-brown. 
  

  

  Having 
  a 
  quantity 
  of 
  more 
  fragile 
  material 
  to 
  examine, 
  this 
  specimen 
  

   was 
  lelt 
  iu 
  water 
  for 
  a 
  number 
  of 
  hours. 
  Meantime 
  it 
  had 
  contracted 
  

   and 
  assumed 
  a 
  very 
  different 
  appearance 
  (Fig. 
  2). 
  The 
  body 
  was 
  

   now 
  nearly 
  globular, 
  with 
  large 
  transverse 
  wrinkles 
  on 
  anterior 
  half, 
  

   the 
  neck 
  protuding 
  like 
  the 
  neck 
  of 
  a 
  water 
  bottle. 
  In 
  dorsal 
  Aiew 
  the 
  

   body 
  ap|)ears 
  somewhat 
  two 
  lobed 
  on 
  account 
  of 
  a 
  shallow 
  longitudinal 
  

   median 
  depression. 
  Head 
  and 
  neck 
  reddish-yellow 
  in 
  front, 
  merging 
  

   into 
  a 
  deei)er 
  orange-red 
  at 
  base; 
  anterior 
  part 
  of 
  body 
  bright 
  orange- 
  

   red. 
  Posterior 
  ])art 
  of 
  the 
  body 
  rich 
  brownish-yellow, 
  neck 
  conical, 
  

   crossed 
  by 
  fine 
  transverse 
  lines. 
  In 
  ventral 
  view 
  neck 
  concave 
  in 
  both 
  

   htngitudinal 
  and 
  tranverse 
  direction, 
  with 
  fine 
  transverse 
  lines; 
  mouth 
  

   at 
  anterior 
  tip, 
  but 
  opening 
  below, 
  elliptical 
  longest 
  diameter 
  longitu- 
  

   dinal, 
  border 
  with 
  radiating 
  wrinkles. 
  Aperture 
  of 
  ventral 
  sucker 
  

   irregularly 
  circular, 
  with 
  puckered 
  border, 
  0.75 
  mm. 
  in 
  diameter. 
  Col- 
  

   oration 
  beneath 
  nearly 
  like 
  that 
  above, 
  head 
  and 
  neck 
  light 
  orange- 
  

   yellow 
  in 
  front, 
  merging 
  into 
  orange-red 
  at 
  base 
  and 
  on 
  front 
  of 
  body, 
  

   becoming 
  light 
  orange-red 
  behind. 
  

  

  Typv.—^o. 
  4853, 
  U.S.N.:\r 
  

  

  The 
  dimensions 
  of 
  the 
  living 
  specimen, 
  after 
  contraction 
  : 
  Length, 
  

   7.25 
  mm.; 
  breadth 
  of 
  globular 
  body, 
  0.75; 
  breadth 
  of 
  head, 
  i. 
  e., 
  at 
  oral 
  

   sucker, 
  1.5; 
  breadth 
  of 
  neck 
  at 
  base, 
  immediately 
  in 
  front 
  of 
  ventral 
  

   sucker, 
  .'? 
  ; 
  distance 
  between 
  suckers, 
  centers, 
  2.0 
  ; 
  thickness 
  of 
  body, 
  5.5. 
  

  

  The 
  alcoholic 
  specimen 
  was 
  cut 
  in 
  two 
  by 
  a 
  median 
  longitudinal, 
  

   dorso- 
  ventral 
  section, 
  and 
  the 
  following 
  points 
  noted: 
  The 
  muscular 
  

   pharynx 
  follows 
  the 
  oral 
  sucker 
  directl3\ 
  The 
  cirrus 
  pouch 
  is 
  in 
  the 
  

   neck, 
  anterior 
  to 
  the 
  ventral 
  sucker; 
  the 
  external 
  opening 
  of 
  the 
  cirrus 
  

   is 
  apparently 
  just 
  back 
  of 
  the 
  mouth. 
  Behind 
  the 
  ventral 
  sucker 
  the 
  

   body 
  is 
  crossed 
  by 
  cavities 
  which 
  contain 
  a 
  black 
  or 
  very 
  dark-brown 
  

   granular 
  substance. 
  No 
  ova 
  were 
  seen. 
  The 
  following 
  dimensions 
  in 
  

   millimeters 
  were 
  obtained 
  fiom 
  the 
  alcoholic 
  specimen 
  : 
  Antero-posterior 
  

   diameter 
  of 
  oral 
  sucker, 
  1.21; 
  dorso- 
  ventral 
  diameter, 
  O.D.j; 
  antero- 
  

   posterior 
  diameter 
  of 
  ventral 
  sucker, 
  2; 
  dorso-ventral 
  diameter, 
  lA; 
  

   length 
  of 
  pharynx, 
  0.74; 
  dorso-ventral 
  diameter 
  of 
  same, 
  0.03. 
  

  

  19. 
  DISTOMUM 
  SIMPLEX 
  Rudolphi 
  (?). 
  

  

  (Plate 
  XLVII, 
  tigs. 
  3-7.) 
  

  

  Dlstomum 
  simplex 
  Du.iardin, 
  Hist. 
  Niit. 
  d. 
  Helm., 
  1845, 
  p. 
  466. 
  — 
  Diesixg, 
  Syst. 
  

   Helm., 
  I, 
  I850,p.343.— 
  Olsson, 
  Luud'a 
  Univ. 
  Arsskrift, 
  1868, 
  IV, 
  p. 
  34, 
  pi. 
  

   n, 
  ligs. 
  81,82. 
  — 
  Levinsen, 
  Gronlands 
  Trematodfauna, 
  1881, 
  p. 
  18, 
  pl.iii, 
  fig. 
  

   1.— 
  Stossich, 
  Dist. 
  d. 
  Pesc, 
  1886, 
  p. 
  30. 
  

  

  Body 
  unarmed, 
  depressed, 
  elongated 
  linear, 
  somewhat 
  constricted 
  in 
  

   the 
  vicinity 
  of 
  the 
  testes, 
  neck 
  short, 
  narrow 
  in 
  front, 
  posterior 
  end 
  

   rounded. 
  Mouth 
  subterminal, 
  aperture 
  orbicular. 
  Ventral 
  sucker 
  very 
  

   prominent, 
  twice 
  the 
  diameter 
  of 
  the 
  oral 
  sucker. 
  (Esophagus 
  equal 
  

  

  