660 DESCRIPTION OF T^NIA NANA, 



Further, the nearer the joints approach the middle of the body, 

 the more does the above-mentioned granular mass assume the appear- 

 ance of a number of closely packed lobes. The latter are grouped 

 together into an irregular, two-lobed figure, the parts of which are 

 distributed over the two lateral portions of the joint. Close behind 

 the mass there is observed another structure of a more finely granular 

 nature which I have recognised as the yolk-gland, whUe the organ 

 lying above ■ it represents the two ovaries. The testes are three ia 

 number, and situated near the posterior border of the segment. 



In the joints of the middle of the body a new structure appears 

 behind the cirrhus- pouch, which, on account of the increasing 

 breadth of the segments, has in the meantime drawn nearer and 

 nearer to the side. It is a body of a pear-like form, which has 

 an almost fatty and shining appearance, and at first sight might be 

 interpreted as a vesicula seminalis. And, indeed, the contents of this 

 body consist of seminal filaments, closely aggregated into an almost 

 homogeneous mass; nevertheless I am quite convinced by the ex- 

 amination, not only of Taenia nana, but also of the related forms ^ 

 that it is not a vesicula seminahs, but a receptaculum seminis. 

 It is filled by means of a short vagina, which opens beside rather 

 than under the cirrhus-pouch, and consequently can but rarely 

 be observed with perfect distinctness. As the filling proceeds, the 

 female genital organs become gradually more shrivelled and blanched, 

 while, on the other hand, the uterus becomes distended with numerous 

 corpuscles, which can soon after be recognised as eggs. The more 

 these develop, the more does the receptacle lose its former refractive 

 power. It becomes paler and smaller, and, along with the cirrhus- 

 pouch, gradually retires in an anterior direction before the pressure 

 of the uterus, until it comes to lie close to the anterior border, 

 where it is easily overlooked. 



I must contradict the statement of Bilharz, that the eggs of Taenia 

 nana possess a " thick and yellowish " shell. As I have remarked 

 above, I can clearly distinguish two thin and clear, but 

 somewhat firm egg-shells, which are widely separated 

 from each other. The six hooks could be but rarely 

 perceived in the coarsely granular embryonic substance, 

 but in several instances they were discovered in the 



^ „,„ form of little rods, 00095 mm. in length, with bent, 

 Fio. 343. — .,,,,. ° 



Eipe egg of sickle-shaped points. 



TcBnm. nana, Only a few calcareous corpuscles of insignificant size 



with embryo. ,.., . ^ ° 



( X 250.) were distributed through the parenchyma of the body. 



^ It taken in connection with the foregoing observations by Stieda, Feuereisen, and 

 Steudener, my communioatiMiL^mJ^ffiomewhai,«jBfflte^ picture of the structure of the 



