84 BOAED OP AGRICULTURE. 



lungs, heart, and other organs, and cause for a time great irri- 

 tation and inflammation of these and other parts by their move- 

 ments in forcing and boring passages for themselves in the 

 tissues ; but thej all eventually perish, while still small, in 

 such localities, and those that get into the liver and. abdomi- 

 nal viscera are the only ones that survive and develop to their 

 full size, becoming the water-bladders, or " Ot/sticercus tenu- 

 icolUs" first described. 



The complete history of this, like the other tape-worms, 

 previously described, has been ascertained beyond doubt by 

 direct experiment. In this case the water-bladders have been 

 given to dogs, and at the proper time the dogs have been killed, 

 when the mature tape-worms have always been found corres- 

 ponding in number to 'the number of water-bladders eaten, 

 and in size to the length of time. And then the eggs or joints 

 of the tape-worms have been given to lambs ; and although 

 such lambs generally die in the course of five or six days, 

 when they swallow large numbers, yet even in that short time 

 the young worms have been found in vast numbers already 

 distributed in the system ; but when only a few eggs are em- 

 ployed, they do not cause immediate death. And in this way 

 Prof. Leuckart has studied their complete development. This 

 tape-worm, in its mature state, does not inhabit the human 

 body. Dr. Moller even swallowed several of the living blad- 

 der-worms without any result. 



When these young worms have once got into the system of 

 a sheep, there is no remedy. In this case, prevention is our 

 only hope ; and to this end the same means should be used as 

 ao-ainst the Tcenia coenurus and T. echinococcus, to be de- 

 scribed farther on. Especial care should always be taken to 

 destroy the water-bladders and all other parasites observed in 

 slaughtering animals, as well as those removed from living- 

 animals by medicines or surgical operations ; for in many cases 

 the eggs are capable of retaining their vitality for many weeks 

 or months. They should never be thrown aside as harmless, 

 or even buried, but should be destroyed by scalding hot water 

 or fire. Much may be done, also, in diminishing the numbers 

 of this and other parasites by frequently doctoring those dogs 



