﻿522 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol.xx. 
  

  

  descriijtions 
  of 
  the 
  above 
  species. 
  Dimensions: 
  Length, 
  20 
  mm.; 
  

   breadth 
  at 
  ventral 
  sneker, 
  3; 
  thickness 
  at 
  ventral 
  sucker, 
  2.75; 
  maxi- 
  

   mum 
  breadth, 
  3.2; 
  diameter 
  near 
  posterior 
  end, 
  1.5; 
  longitudinal 
  diam- 
  

   eter 
  of 
  apeiture 
  of 
  ventral 
  sucker, 
  1.4 
  ; 
  transverse 
  diameter 
  of 
  same, 
  0.8. 
  

  

  Body 
  elongated 
  sublinear, 
  depressed 
  unarmed, 
  transversely 
  rugose, 
  

   posteriorly 
  attenuate. 
  The 
  neck 
  had 
  evidently 
  been 
  reflected 
  dorsally 
  

   nearly 
  at 
  right 
  angles 
  to 
  body. 
  

  

  For 
  about 
  6.5 
  mm. 
  back 
  of 
  the 
  ventral 
  sucker 
  tlie 
  body 
  was 
  tilled 
  with 
  

   the 
  voluminous 
  folds 
  of 
  the 
  uterus, 
  the 
  latter 
  crowded 
  with 
  ova. 
  

  

  Long 
  diameter 
  of 
  ova, 
  0.07G 
  mm.; 
  short 
  diameter, 
  0.052. 
  

  

  Fragment 
  of 
  large 
  distomum 
  from 
  stomach 
  of 
  barndoor 
  skate 
  (Raja 
  

   hvvi.s). 
  No. 
  4S70, 
  U.S.N.M.; 
  Woods 
  Holl, 
  Massachusetts, 
  November 
  4, 
  

   1887; 
  Viual 
  N. 
  Edwaids, 
  collector. 
  

  

  16. 
  DISTOMUM 
  MACROCOTYLE 
  Diesing. 
  

  

  (Plates 
  XLV, 
  tigs. 
  8-10; 
  XLVI, 
  tigs. 
  1-5.) 
  

  

  Distomum 
  macroootyle 
  Diesing, 
  Revis 
  d. 
  Myzhelm, 
  p. 
  342. 
  — 
  Olsson, 
  Liiud's 
  

   Uuiv. 
  Arsskrift, 
  IV, 
  p. 
  24, 
  pi. 
  v, 
  tigs. 
  100, 
  101. 
  — 
  Stossicii, 
  Dist. 
  d. 
  Pesc, 
  p. 
  

   20. 
  — 
  MoNTiCELLi, 
  Nat. 
  Sicil. 
  An., 
  XII, 
  1893, 
  p. 
  10 
  (extract). 
  

  

  Body 
  unarmed, 
  round, 
  straightish, 
  attenuate 
  both 
  ijosteriorly 
  and 
  

   anteriorly, 
  linear- 
  fusiform. 
  IS^eck 
  slender-conical, 
  retlexed, 
  sometimes 
  

   arched. 
  Mouth 
  subterminal, 
  aperture 
  transverse, 
  in 
  alcoholic 
  speci- 
  

   mens, 
  said 
  to 
  be 
  circular 
  in 
  life. 
  V^entral 
  sucker 
  very 
  prominent, 
  

   globose, 
  sessile 
  twice 
  the 
  diameter 
  of 
  the 
  oral 
  sucker, 
  aperture 
  longi 
  

   tudinally 
  elliptical 
  in 
  alcohol, 
  circular 
  in 
  life. 
  Genital 
  aperture 
  in 
  

   anterior 
  jiart 
  of 
  neck 
  near 
  oral 
  sucker. 
  Testes 
  two, 
  large, 
  behind 
  ven- 
  

   tral 
  sucker, 
  ventrally 
  placed. 
  Ovary 
  about 
  the 
  middle 
  of 
  the 
  post 
  

   acetabular 
  region 
  of 
  the 
  body. 
  Greater 
  part 
  of 
  body 
  tilled 
  with 
  tlie 
  

   folds 
  of 
  the 
  uterus, 
  which 
  are 
  crowded 
  with 
  small 
  ova. 
  

  

  Sixteen 
  of 
  these 
  worms 
  (No. 
  4854, 
  IJ.S.N.M.) 
  were 
  found 
  in 
  a 
  lot 
  of 
  

   Distoma 
  from 
  the 
  intestine 
  of 
  Mola 
  mola^ 
  oft' 
  Marthas 
  Vineyard, 
  Massa- 
  

   chusetts, 
  September 
  10, 
  1880; 
  Vinal 
  ^S". 
  Edwards, 
  collector. 
  

  

  Fig. 
  1) 
  was 
  made 
  from 
  the 
  inner 
  aspect 
  of 
  the 
  left 
  half 
  of 
  a 
  speci- 
  

   men 
  which 
  had 
  been 
  S])lit 
  in 
  two 
  longitudinally. 
  It 
  reveals 
  many 
  folds 
  

   of 
  the 
  uterus, 
  both 
  dorsally 
  and 
  ventrally 
  placed, 
  with 
  an 
  anterior 
  

   prolongation 
  dorsal 
  in 
  the 
  neck. 
  Some 
  folds 
  of 
  the 
  vas 
  deferens 
  are 
  

   seen 
  lying 
  above 
  the 
  ventral 
  sucker. 
  The 
  vitellaria 
  are 
  axially 
  situated, 
  

   extending 
  from 
  the 
  ventral 
  sucker 
  to 
  about 
  the 
  posterior 
  fifth. 
  The 
  

   cirrus 
  bulb 
  is 
  seen 
  lying 
  close 
  behind 
  the 
  oral 
  sucker. 
  

  

  One 
  of 
  the 
  larger 
  specimens 
  yielded 
  the 
  following 
  measurements: 
  

   Length, 
  14 
  mm.; 
  maximum 
  diameter 
  of 
  body, 
  1.7; 
  diameter 
  of 
  neck, 
  

   0.88; 
  distance 
  between 
  suckers, 
  1.7; 
  diameter 
  of 
  ventral 
  sucker, 
  1.4; 
  

   diameter 
  of 
  oral 
  sucker, 
  0.G5: 
  transverse 
  diameter 
  of 
  oral 
  aperture, 
  

   0.35; 
  longitudinal 
  diameter 
  of 
  oral 
  aperture, 
  0.11. 
  

  

  The 
  ova 
  measure 
  0.02^5 
  and 
  0.017 
  mm. 
  in 
  the 
  two 
  principal 
  diameters. 
  

  

  Transverse 
  and 
  longitudinal 
  series 
  of 
  sections 
  were 
  prepared 
  and 
  

  

  