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can either be found in scrum-filled cavities of tbe liver or attached to 

 the outside, or perhaps free in the cavity. Still later, the liver shows 

 places puckered up, which are caused by the reparative process and tbe 

 contraction of the newly-formed tissue. There will be numerous chan- 

 nels beneath the serous membrane visible to the unaided eye. The bil- 

 iary canals will be found thickened and enlarged at places to the size 

 of a hazel-nut, or even larger. In these dilatations are flukes of con- 

 siderable size, surrounded by a greenish black, sticky mass. Some- 

 times hard limy fragments are found in them. The substance of the 

 liver becomes very rotten, and crackles under pressure by the finger. 

 When the flukes migrate healing takes place to some degree, but tlie 

 liver will never look healthy. It will grow considerably smaller and 

 become much whiter, due to the connective tissue changes which take 

 place. 



Preventive treatment. — Thomas has formulated rules of prevention 

 against this parasite, which are founded on its life history and seem to 

 be eminently practical. He says : 



(1) All eggs of the liver fluke must be rigorously destroyed. Manure of rotten 

 sheep or other infected animals must not be put on wet ground. As the liver and 

 intestines contain eggs, these, too, must be destroyed or put in the compost heap. 

 The manureofaflfected animals should not be stored where there is a drainage from it 

 to the ueighboriug grass. It should be mixed with lime and salt before being spread 

 on meadows or cultivated fields. 



(2.) If sheep are iufeeted, let them be sent to the butcher at once, unless thej- are 

 specially valuable aud are not badly affected. If kept, they must not be put onto 

 wet ground. 



The above advice is preferable with all common stock; and the ex- 

 ceptions, when medicine should be tried, are very few. Stock should 

 be very valuable to repay the expense of care and treatment in face of 

 the large percentage of death which occurs in this disease, and the ill 

 condition of the remnant after recovery. 



(3.) Care must be taken to avoid introducing eggs of the fluke either with manure 

 or fluked sheep, or in any other way. Rabbits aud hares must not be allowed to in- 

 troduce the eggs. 



The most prolific source of introducing parasites is in the iutroduc 

 tion of infected sheep, and purchas(5rs should learn all they can of the 

 history of the animals they buy, aud not purchase from diseased flocks. 



(4.) All heavy aud wet ground must be thoroughly drained. 



Draining is of advantage in many ways. It makes tillable land of 

 what was before useless, either for pasturage (as shown by its infecting 

 the flocks with a fatal disease) or for cultivation. 



(5.) Dressings of lime and salt (or both) should be spread over the ground at the 

 proper season to destroy the embryos, the cysts of tbe fluke, aud also the suail whicli 

 acts as host. 



After draining, such fields should be cultivated and suitable crops 

 raised on them. 



(6.) Sheep must not be allowed to graze closely, for the more closely they graze the 

 more fluke-germs will they pick up. 



