44 ANIMAL PAKASITES. 



the last-mentioned experiment, I must maintain this opinion in 

 opposition to Leuckart, who seems to think that when the eggs 

 are masticated the embryo must necessarily be always destroyed, 

 or else that, from their small size, all the eggs must pass uninjured 

 through the teeth. It appears that eggs which have passed the 

 stomach and reached a portion of the intestine below the stomach 

 in an uninjured state, may still give issue to their six-hooked 

 embryos, from the discovery by Leuckart of a free embryo in the 

 intestinal mucus of a part of the small intestine ; and I also 

 consider that this view is supported by an experiment of 

 Leuckart's, which will be mentioned hereafter, according to 

 which the caudal vesicle of those Cysticerci which are left for a 

 time in contact with the fluid of the stomach in experiments in 

 artificial digestion, and then enclosed in a piece of the small 

 intestine, is readily digested ; whilst when the Cysticerci are 

 enclosed at once in the small intestine, no digestion of the 

 proglottis takes place. We may consequently suppose with some 

 probability that the temporary sojourn of the eggs in the stomach 

 of an animal at least facilitates the exclusion of the brood 

 materially. This question is especially important for the theory 

 of the production of Cysticercus cellulosce in the human body. 

 If we consider, on the one hand, that it cannot be denied that 

 Taenia solium is the producer of the germs of Cyst, cellulosce ; and 

 on the other that, in many cases of Cysticerci in the human 

 body, the simultaneous or previous existence of T. solium in the 

 same subject has been established beyond all doubt (as in the 

 case of Cyst, cellulosce in the brain of a person of weak intellect, 

 from whom Giinsburg had previously expelled a Taenia solium ; in 

 one of the cases of Cysticercus cellulosce in the eye, described by 

 Von Graefe, in which the woman suffered from T. solium ; and in 

 the case narrated by Moller, in which a woman who had been 

 epileptic for many years, and who had, twenty years before, 

 visited the hospital at Hamburgh, to get a tape-worm expelled, 

 and who exhibited Cyst, cellulosce in the brain) ; and if at the 

 same time we do not forget how often the patient is quite una- 

 ware of his being infested by a tape-worm, we may certainly 

 come, without much reflection, to the idea that it is by no means 

 improbable that in such a case the bearer of the tape-worm may 

 have infected himself with the Cysticerci. 



There are various ways in which this infection may take place. 

 The infested person, when the proglottides have fallen into his 



