﻿NO. 
  1125. 
  CESTODE 
  PARASITES 
  OF 
  FISHES— 
  LINTON. 
  441 
  

  

  23. 
  RHINEBOTHRIUM 
  LONGICOLLE 
  Linton. 
  

   (Plate 
  XXXIII, 
  lius. 
  2-4.) 
  

  

  Bhinebothrium 
  longicoJle 
  Linton, 
  U. 
  S. 
  Fish 
  Com. 
  Rept., 
  1887, 
  pp. 
  775-778, 
  pi. 
  vi, 
  

   fige. 
  1-4. 
  

  

  Nos. 
  4805, 
  4802, 
  4804. 
  A 
  few 
  fragments 
  of 
  strobile, 
  no 
  scolex, 
  over- 
  

   looked 
  in 
  first 
  description 
  of 
  the 
  si^ecies; 
  collected 
  in 
  August, 
  1884, 
  from 
  

   intestine 
  of 
  Myliohails 
  freminviUei 
  belong 
  to 
  this 
  species. 
  

  

  In 
  the 
  summer 
  of 
  1889 
  I 
  encountered 
  this 
  worm 
  on 
  three 
  different 
  

   occasions, 
  each 
  time 
  in 
  the 
  cow-nosed 
  ray 
  {Rhinoptera 
  honasius), 
  hab- 
  

   itat 
  added. 
  August 
  1, 
  ten 
  specimens 
  (from 
  one 
  ray); 
  August 
  14, 
  one 
  

   specimen-, 
  Angnst 
  IG, 
  two 
  specimens. 
  

  

  This 
  species 
  was 
  also 
  found 
  in 
  the 
  United 
  States 
  National 
  Museum 
  

   collection 
  — 
  no 
  catalogue 
  number; 
  label 
  reads: 
  ''Intestine 
  of 
  small 
  Baia, 
  

   Penikese, 
  July 
  13, 
  1874.''* 
  The 
  vial 
  contains 
  a 
  number 
  of 
  fragments, 
  

   three 
  of 
  them 
  with 
  scolices; 
  length 
  of 
  longest 
  about 
  25 
  mm. 
  

  

  A 
  specimen 
  in 
  the 
  lot 
  collected 
  on 
  August 
  IG 
  was 
  at 
  first 
  taken 
  to 
  be 
  

   a 
  distinct 
  species, 
  but 
  subsequent 
  examination 
  of 
  the 
  alcoholic 
  speci- 
  

   men 
  proves 
  it 
  to 
  belong 
  to 
  this 
  species. 
  For 
  some 
  reason, 
  jirobably 
  on 
  

   acconnt 
  of 
  age, 
  the 
  bothrial 
  costie 
  are 
  very 
  indistinct, 
  which 
  gave 
  the 
  

   specimen 
  a 
  very 
  different 
  appearance, 
  especially 
  in 
  the 
  living 
  specimen. 
  

   Length, 
  37 
  mm.; 
  length 
  of 
  ripe 
  proglottis, 
  1.3. 
  Figs. 
  3 
  and 
  4 
  rei)re- 
  

   sent 
  the 
  ova 
  of 
  this 
  species 
  as 
  they 
  were 
  observed 
  on 
  different 
  occasions. 
  

   The 
  thin 
  pellicle 
  which 
  surrounds 
  the 
  ovum 
  is 
  extended 
  into 
  a 
  long 
  

   filament, 
  which 
  is 
  five 
  or 
  six 
  times 
  the 
  length 
  of 
  the 
  ovum. 
  In 
  fhe 
  

   proglottis 
  these 
  filaments 
  are 
  felted 
  together. 
  When 
  they 
  are 
  extended 
  

   in 
  water 
  they 
  remain 
  in 
  a 
  mass 
  for 
  a 
  time, 
  but 
  ultimately 
  lose 
  the 
  fila- 
  

   ments. 
  At 
  least, 
  in 
  a 
  lot 
  of 
  ova 
  which 
  had 
  been 
  lying 
  for 
  some 
  time 
  in 
  

   sea 
  water 
  filaments 
  were 
  found 
  on 
  only 
  a 
  part 
  of 
  the 
  ova, 
  while 
  those 
  

   which 
  were 
  seen 
  in 
  place 
  through 
  the 
  walls 
  of 
  the 
  proglottis 
  were 
  all 
  

   provided 
  with 
  filaments. 
  

  

  The 
  dimensions 
  of 
  the 
  largest 
  ova 
  in 
  one 
  lot 
  were 
  0.028 
  and 
  0.038 
  mm. 
  

   in 
  the 
  two 
  principal 
  diameters. 
  The 
  filaments 
  were 
  five 
  or 
  six 
  times 
  as 
  

   long 
  as 
  the 
  ova. 
  

  

  This 
  species 
  was 
  first 
  found 
  in 
  Myliohatis 
  freminvillei. 
  

  

  24. 
  RHINEBOTHRIUM 
  MINIMUM 
  Beneden. 
  

  

  (Plate 
  XXXIII, 
  fiff.5.) 
  

  

  Echeneibofhrium 
  minimum 
  Beneden, 
  Diesing, 
  Revis. 
  d. 
  Cephal. 
  Parani., 
  p. 
  268. 
  

  

  No. 
  4803, 
  U.S.N.M.; 
  United 
  States 
  Fish 
  Commission, 
  collector; 
  off 
  

  

  Marthas 
  Vineyard, 
  Massachusetts, 
  1881, 
  station 
  919. 
  From 
  stomach 
  of 
  

  

  Raja 
  Iannis. 
  

  

  The 
  vial 
  contains 
  several 
  fragments, 
  among 
  which 
  are 
  two 
  strobiles 
  

   with 
  s(;olices. 
  

  

  Dimensions 
  of 
  one 
  of 
  these: 
  Length, 
  9 
  mm.; 
  length 
  of 
  bothrium, 
  

   0.5; 
  breadth 
  of 
  bothrium, 
  0.2; 
  diameter 
  of 
  neck, 
  0.2; 
  length 
  of 
  postero- 
  

   median 
  segments, 
  0.36; 
  breadth 
  of 
  same, 
  0.4; 
  length 
  of 
  posterior 
  seg- 
  

  

  