512 DEVELOPMENT AND GROWTH OF T^EXIA. SOLIUM. 



even in the writings of Hippocrates and in Aristotle, who, in his 

 natural history, ranks the bladder-worms (^aXfat, grandines) among 

 the diseases of swine. 1 The first knowledge of the bladder-worms 

 of the pig is lost in antiquity ; some would, indeed, assert that the 

 Mosaic law against eating the flesh of that animal had not a religious 

 but a sanitary basis. 



Fresh and more accurate investigations were necessary before the 

 animal nature of the bladder- worms of the pig could be generally recog- 

 nised. And these were forthcoming; for shortly before Werner's 

 discovery, mentioned above, Otto Fabricius 2 and Goze 3 has brought 

 forward most convincing proof that the structures in question were 

 true bladder- worms. Since this amounted really only to a confirmation 

 of a previous discovery, both investigations remained unacknowledged, 

 but it was no small merit to have established the nature of the bladder- 

 worms for all future time. 



2. The Adult Tape- Worm. 



The experimental helminthologist can rarely have the opportunity 

 of examining the metamorphoses of the bladder-worm of the pig 

 within man himself. This is not, however, necessary ; for though 

 man is the only host infested with Tcenia solium, he is not the only 

 creature in whose intestine the bladder-worm may attain to further 

 development. Even in other mammals it is possible to follow the 

 first stages, at least, in the metamorphosis. One cannot always reckon 

 with certainty on a positive result, for the experiment often mis- 

 carries the worms are digested, and only the hardly recognisable 

 remains are left. In other cases, however, one finds on examination 

 which must not, of course, be too long postponed 4 the first phases of 

 the metamorphosis of the bladder- worm, which entirely agree with what 

 we have seen (p. 382) in the case of the bladder-worm from the rabbit. 



To refer only to one of my experiments, I fed a rabbit with about 

 thirty pieces of adult bladder- worm from the pig. The dissection 



1 "Histor. Animal.," lib. viii., cap. 81. Here also Kuchenmeister detects something 

 erroneous in my statement. 



3 Nova Acta Soc. Hafn., t. iL, p. 287, or Deutsckes gemeinniitziges Arckiv, Jahrg. ii., 

 Quartal i. : Leipzig, 1788. 



8 " Neueste Entdeckung, dass die Finnen im Schweinefleisch keine Driisenkrankheit, 

 sondern wahre Bandwiirmer sind " : Halle, 1784. The fact that in Goze's great work, 

 which appeared in 1782, there is no mention of the bladder- worm of the pig, has led 

 Kuchenmeister (loc. cit.) to the false conclusion " Goze does not know the Cysticcrcus 

 rellulosce, though Pallas does." I am not aware that the latter has especially considered 

 the bladder-worm of the pig, but Goze has certainly earned a much greater merit by his 

 account of this worm. 



4 Heller's statement that the tape-worms introduced perish after twenty-four hours 

 (loc. cit., p. 597, Eng. transL, p. 718) is somewhat too narrow, as the following case shows. 



