PATHOLOGICAL RESULTS OF THE BLADDEE-WOIIM. 539 



through inflammation heing set up in the wall of the intestine and in 

 other organs. 1 There is, however, no proof of the correctness of this 

 supposed connection of cause and effect. Other investigators have 

 always succeeded in keeping their animals alive, and free from any 

 pathological symptoms, when fed repeatedly with long chains of 

 proglottides, even though they experimented with young pigs, which, 

 according to Gerlach (p. 495), are alone suited for the development of 

 the "bladder-worms. The fact that the young bladder-worms lie at 

 first almost free, and only gradually form a firm capsule, while those 

 in the ox have from the first a thick sheath of exuded lymph, is 

 certainly not in favour of the idea that the pig reacts against the 

 invading brood as strongly as does the ox. We need hardly note 

 that this is very important, for the pig, from its mode of life, is much 

 more frequently infected than the ox. 



The genetic relation between the bladder-worm and Tcenia solium 

 makes it evident that its occurrence and frequency in various districts 

 must be very varied. But it is not the distribution and frequency 

 of the tape-worm which alone determine this, for it depends still 

 more, perhaps, on the condition and housing of the swine. Where 

 the swine are bred in a half-wild state, being generally driven out to 

 the meadows or the oak-woods, where they have to seek their own 

 food, then their opportunities of infection are more frequent than 

 when they are kept and fed in the styes. In fact, the introduction 

 of the custom of feeding in the stye has in many cases markedly 

 reduced the frequency of Cysticercoid disease. This can of course be 

 hoped for only when the pigs are kept in a cleanly way, and not allowed 

 to get near dung-heaps or privies, which are always to a certain ex- 

 tent dangerous. Their food must of course be freed from all possible 

 contact with human excrement. Particularly must any tape-worm 

 patient be removed as rapidly as possible from near the swine, 

 since his presence is a source of danger to the whole herd. This is 

 strikingly illustrated by an observation made by Fiirstenberg, 2 which 

 tells us of a tape- worm patient who once infected a whole herd of 

 fifteen pigs, which had broken through the barrier separating them 

 from the privy. Two of the number exhibited an acute affection, 

 which was designated Cestode tuberculosis with doubtful accuracy, 

 and the others were rendered quite useless. 



Since human excrement is deposited in very varied places where- 

 ever man exists, it is readily conceivable that wild swine may also be 

 occasionally infected, but this is rare, as one would expect in the 

 case of animals living far from the dwellings of man. 



1 Loc. cit., p. 68. 



2 Hosier, Archivf. pathol. Anat., Bd. xxii?., p. 426, 1862. 



