305 



with three pairs of hooklets, by which it is able to burrow in tis- 

 sues, and make its way to any j)art of the human system. After 

 it has found its proper nidus, be it muscle, brain, eye, or other 

 organ, and has become encysted, its hooklets drop off, and from 

 its walls a protuberance grows inwards, which gradually changes 

 into a head, neck, and body, or, in other words, becomes the sco- 

 lex. This at first remains enclosed within the embryonic blad- 

 der as a receptacle, but later the animal pushes itself free. Its 

 head has now become that of the true Ttenia, and from it depends 

 the former receptacle as a bladder. Siebold maintains that this 

 cyst is only a joint of the scolex, which has become dropsical ; but 

 Kuchenmeister (and his views are adopted by all modern pathol- 

 ogists) insists that this is another stage of development, and the 

 normal condition of the animal. Now, unless the encysted ani- 

 mal is set free artificially, the genei-ation stops here ; but if, in 

 any way, it escape, and again find entrance within the intestinal 

 canal, it fastens itself by its head to the walls, its bladder drops 

 off, leaving behind the marks of attachment on the oldest joint, 

 and in its place the true joints of the Tjenia are developed, form- 

 ing the animal with which we started. 



It is only by this method that a Taenia can be produced ; for 

 the eggs or embryos of the proglottis either pass into the tissues, 

 and become there encysted scolices or nurses, or else pass away 

 with the fiBces, At all events, they are never converted pri- 

 marily into Tainiae, else we should find tapeworms as plentiful as 

 ascarides. To account for the production of Tgenite, therefore, we 

 must admit the scolex within the intestinal canal, and this may 

 be done more easily than we imagine. The head of the Cysti- 

 cercus is but a mere mite, and it is not necessary that its bladder 

 should accompany it, which, as above mentioned, drops off, leav- 

 ing behind the mark of its former attachment. We know how 

 general a disease this parasite forms among swine ; but it is not 

 wholly confined to them ; for we find it also, though seldom, 

 in the bear, deer, and ox, not to mention many other animals, so 

 that nations who eat no pork may be infested by Ttenire. It is 

 probable that many scolices may pass through the intestinal canal 

 of man, and yet not generate the tapeworm, for it must attach 

 itself to its walls before the joints are produced. 



PROCEEDINGS B. S. N. H. — VOL. VI. 20 APRIL, 1868. 



