TREATMENT PROPHYLACTIC. 169 



knows but what a " sleek little mouse," who invades 

 our larder by night, may not deposit the OVA of the 

 echinococcus on our bread, butter, and cold meat, which 

 we innocently partake of at our first meal on the 

 morrow, and more particularly cheese. Again, the 

 animal may be conveyed to the inward man by means 

 of impure water, raw vegetables, fruit, and roots. Like 

 the embryos of other "Tsenise," however, they are so 

 small as to escape the field of ordinary vision. Their 

 migration, however, is certainly performed like that of 

 the embryos of other Tsenise, by passing into the system, 

 as I have ventured to suggest, either by ABSORPTION or 

 by perforating the intestines, and getting into the 

 abdominal cavity, where they prefer attaching them- 

 selves to the liver or the kidneys, or to the organs in the 

 cavity of the chest, or by migration along the " ductus 

 communis choledocus" into the liver, or to the outer 

 surface of that organ. 



The hydatids of human beings, says "Thudicum," 

 most frequently accompany them to their graves ; or 

 at all events, they are not permitted to continue their 

 dangerous existence ; but the echinococci of sheep or 

 lambs are again set free in the process of slaughtering, 

 and are in turn to be devoured by dogs, " and it may 

 be " by cats, pigs, ducks, rats, and mice, whose favourite 

 haunt is the slaughterhouse, butchers' shambles, or 

 the knacker's yard, to be again developed into tape- 

 worms. It has not yet been clearly proved that the 

 animals herein mentioned, in addition to the dog, are 

 not infested by the ova of the echinococcus. While man, 

 then, does not contribute to the multiplication and 

 propagation of the worm, his constant liability to the 



