﻿Nc. 
  n:i:i. 
  TREMATODE 
  r 
  All 
  A 
  SITES 
  OF 
  FISHES— 
  LINTay. 
  537 
  

  

  pharynx, 
  0.14; 
  iriaximuin 
  diameter 
  of 
  body, 
  O.oL*; 
  diameter 
  at 
  posterior 
  

   end, 
  0.22; 
  lengtli 
  of 
  oral 
  spines 
  (weak 
  and 
  indistinct), 
  about 
  0.04. 
  

  

  Found 
  in 
  the 
  peritoneum 
  of 
  Morone 
  american<i 
  ; 
  Woods 
  Hell, 
  Massa- 
  

   chusetts, 
  September 
  2, 
  1885. 
  

  

  CYSTS 
  WITH 
  TREMATODE 
  OVA. 
  

  

  Nos. 
  4865, 
  5503, 
  U.S.lSr.M. 
  Associated 
  with 
  the 
  two 
  BiHloma 
  from 
  the 
  

   wlute 
  perch 
  (Morone 
  <(mericaua) 
  were 
  numerous 
  minute 
  cysts 
  accom- 
  

   ])anied 
  with 
  patches 
  of 
  dark-brown 
  pigment, 
  on 
  the 
  serous 
  covering' 
  of 
  

   tlie 
  liver, 
  mesentery, 
  etc. 
  Upon 
  examination 
  there 
  were 
  found 
  the 
  

   renmins 
  of 
  a 
  distomum, 
  little 
  more 
  than 
  the 
  convoluted 
  uterus 
  packed 
  

   with 
  ova. 
  The 
  latter 
  were 
  small, 
  0,018 
  and 
  0.012 
  mm. 
  in 
  the 
  two 
  prin- 
  

   ci])al 
  diameters. 
  Scattered 
  through 
  the 
  serous 
  membrane 
  were 
  numer- 
  

   ous 
  globular 
  cysts, 
  with 
  thick 
  walls 
  of 
  connective 
  tissue, 
  each 
  containing 
  

   one 
  or 
  more 
  of 
  these 
  ova. 
  Some 
  of 
  the 
  cysts 
  seem 
  to 
  have 
  formed 
  

   around 
  a 
  cluster 
  of 
  ova. 
  One 
  cyst 
  containing 
  two 
  ova 
  measured 
  0.048 
  

   and 
  0.04 
  mm. 
  in 
  its 
  two 
  iirincipal 
  diameters; 
  another, 
  globular, 
  0,053 
  

   muK 
  in 
  diameter 
  contained 
  three 
  ova; 
  another 
  with 
  five 
  ova 
  was 
  O.OO 
  in 
  

   di.ameter; 
  the 
  walls 
  of 
  the 
  cysts 
  are 
  relatively 
  thick, 
  in 
  the 
  last 
  case 
  

   being 
  0.017. 
  One 
  large 
  cyst, 
  containing 
  approximately 
  fifty 
  ova, 
  was 
  

   0.1 
  1 
  and 
  0,08 
  in 
  its 
  two 
  principal 
  diameters. 
  

  

  Some 
  ova 
  were 
  found 
  in 
  the 
  serous 
  membrane 
  without 
  cyst, 
  others 
  

   with 
  cysts 
  just 
  beginning, 
  and 
  others 
  with 
  well 
  developed 
  thick-walled 
  

   cysts. 
  Some 
  of 
  the 
  larger 
  cysts 
  contained 
  black 
  pigment 
  patches 
  asso 
  

   ciated 
  with 
  the 
  ova. 
  There 
  were 
  also 
  patclies 
  of 
  pigment 
  in 
  the 
  serous 
  

   membrane, 
  

  

  A 
  diseased 
  ovary 
  of 
  a 
  white 
  perch 
  {M. 
  americana), 
  collected 
  by 
  Mr. 
  

   S. 
  E. 
  Meek, 
  Fulton 
  Market, 
  New 
  York 
  City, 
  October 
  6, 
  1886, 
  from 
  a 
  fish 
  

   taken 
  somewhere 
  in 
  Long 
  Island, 
  New 
  York, 
  may 
  be 
  noticed 
  proi)erly 
  

   in 
  this 
  connection. 
  

  

  The 
  center 
  of 
  the 
  ovary 
  is 
  occupied 
  by 
  an 
  elongated 
  mass 
  of 
  waxy 
  

   consistency 
  and 
  appearance. 
  This 
  mass 
  is 
  made 
  up 
  of 
  the 
  tissue 
  of 
  the 
  

   ovary, 
  ova, 
  and 
  connective 
  tissue, 
  and 
  cysts 
  containing 
  parasites, 
  which 
  

   in 
  most 
  cases 
  have 
  undergone 
  degeneration, 
  but 
  in 
  a 
  few 
  cases 
  revealed 
  

   ova 
  identical 
  in 
  size 
  and 
  appearace 
  with 
  those 
  from 
  the 
  serous 
  coat 
  of 
  

   the 
  liver, 
  etc., 
  described 
  above. 
  

  

  My 
  conclusion 
  is 
  that 
  these 
  waxy 
  masses 
  (42 
  mm. 
  long 
  and 
  14 
  mm. 
  

   thick) 
  are 
  caused 
  by 
  the 
  presence 
  of 
  trematodes, 
  whose 
  ova 
  not 
  having 
  

   been 
  liberated 
  and 
  allowed 
  to 
  come 
  under 
  conditions 
  where 
  development 
  

   would 
  take 
  ])lace, 
  have 
  become 
  encysted 
  and 
  given 
  rise 
  to 
  this 
  patho- 
  

   logical 
  condition 
  of 
  the 
  ovaries. 
  

  

  28. 
  DISTOMUM 
  species. 
  

   (Plate 
  LIII, 
  tigs. 
  1,2.) 
  

  

  Body 
  elliptical, 
  or 
  ovate 
  oblong 
  a 
  little 
  depressed, 
  smooth. 
  Oral 
  

   sucker 
  orbicular, 
  squarish, 
  situated 
  a 
  short 
  distance 
  back 
  of 
  anterior 
  

   end. 
  WMitral 
  sucker 
  a 
  little 
  less 
  than 
  oral 
  sucker. 
  Aj)erture 
  of 
  both 
  

  

  