278 ANIMAL PAEASTTES. 



posteriore '* caudce" parte denuo unitus, ccecus. Porus genitalis 

 inter acetabulum ventrale et canalis " gynaecophori" oriyinem 

 situs. 



FemincE forma dissimilis, tenerrima, gracillima ; corpus teenies- 

 forme, Iceve, hyalinum, antice sensim valde attenuatum, cauda canali 

 nullo apice angustata. Acetabula et canalis cibarms, ut in mare. 

 Porus genitalis cum margine posteriore acetabuli ventralis coatitus. 



Longit. 3 4 tin. ; mas feminam latitudine multo superans. 



Patria : ^Egyptus in hominis vena portarum ejusque ramifica- 

 tionibus et in vesicce urinarice parietibus. In venis meseraicis 

 reperiuntur mares feminam in canali gyncecophoro gerentes, in venis 

 intestinalibus et hepatitis, in vena lienali semper vidui. 



On the 1st of May, 1851, and still further subsequently, 

 Bilharz wrote to Von Siebold, stating that he had found in the 

 blood of the portal vein a new, white, elongated entozoon, re- 

 sembling a nematoid worm when examined with the naked 

 eye, which was a Distomum with a flat body and a cylindrical 

 tail ten times as long as the body. This tail was no loosely 

 attached, deciduous portion of the body, as in the Cercarice, but a 

 continuation of the substance of the body of the worm itself, 

 which was flat and rolled round towards the ventral surface, at the 

 sides forming a semi-canal, and somewhat sinuated at the apex, 

 and into which the bifurcated csecal intestine, which contained 

 blood-corpuscles throughout its whole extent, passed very dis- 

 tinctly. In the veins of the uninjured mesentery, when held up 

 to the light, specimens of the worm were soon found, which 

 harboured a gray filament, moving to and fro, in the furrow of 

 their tails. This filament resembled the animal first described in 

 form, only much more delicate and fine ; its posterior extremity, 

 however, was not rolled into a canal, but band-like and complete, 

 inclosed by the above-mentioned furrow of the other animal like 

 a sword in its sheath, but in such a manner that it could easily 

 be drawn out of this furrow. The first animal was now clearly 

 recognised as the male, and the second as the female. 



Besides the structure already described, the male presents the 

 following peculiarities : It has a smooth, soft skin on the 

 anterior part of the body, and its tail is sprinkled with numerous 

 small tubercles beset with short hairs. Each of the two sucking 

 discs is beset with innumerable, extremely small, apparently flat 

 granules, as is also the inner coat of the canalis gyncecophorus ; 



