27G ANIMAL PARASITES. 



3. Distomum heterophyes (Von Siebold). Found by Bilharz. 



PI. TV, figs. II, 12. 



Descriptio : Dist. heter., hermaphroditum. 



Corpus ovato-oblongum, depressum, subtus planum, supra leviter 

 convexum. Acetabulum oris subapicale, infundibuli forme, parvum. 

 Acetabulum ventrale paululum ante medium situm, magnum {acetabu- 

 lum oris decies et ultra super ans), globosum. Pharynx muscularis, 

 globosa; canalis cibarius ante acetabulum ventrale in 2 partes ceecas 

 divisus. Cirrhus post acetabulum ventrale situs, et oblique cum 

 sinistra ejus parte coaliius, globosus, acetabuliformis, circulo incom- 

 plete setarum 72 minutissimarum, ranudis 5 secundis instructarum 

 coronatus, testiculis organoque germinifero globosis. Longitudine 

 h—r'; latit.v". 



Patria ; JEgyptus ; in hominis intestino tenui bis repertum, 

 numero permagno. 



On the 26th of April, 1851, and once subsequently, Bilharz 

 found a great number of small red points in the intestine of a boy. 

 These were small Distoma, with mature, reddish-brown eggs 

 shining through them. The Distomum is oval, obtuse behind, 

 more acute in front. The buccal sucker is small and funnel- 

 shaped, and opens rather towards the lower surface than ante- 

 riorly. Behind it commences the short, narrow, membranous 

 oesophagus, which is followed by an oblong muscular pharynx, 

 and then by a narrow cibarian canal, which divides as usual, in 

 front of the ventral sucker, into two lateral intestinal tubes, 

 terminating in csecal extremities in the hinder part of the body. 

 The muscular ventral sucker lies before the middle of the belly, 

 and is twelve times as large as the buccal sucker. Behind this 

 lies the penis-sac, which is itself not unlike a sucking disc upon 

 superficial examination, and exhibits on its surface a circle of 

 seventy-two small, peculiarly formed horny filaments (analogous 

 to the fish-basket-like horny ribs of the penis-sac of Polystonium 

 and Octobothrium, Von Sieb.), which present towards the sides 

 five small branches of equal length, placed one behind the other, 

 and set on at an acute angle. At the spot where the penis- 

 sac is coalescent with the ventral sucker, the horny filaments 

 are wanting. In the hinder end of the body lie the two roundish 



