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can either be found in serum-filled cavities of the 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 the 

 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 e^gs of the liver fluke must be rigorously destroyed. Manure of rotten 

 sheep or other infected animals must not he put on wet ground. As the liver aud 

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

 The manure of affected animals should not he stored where there is a drainage from it 

 to theneighhoring grass. It should he mixed with lime and salt before being spread 

 on meadows or cultivated fields. 



(2.) If sheep are infected, let them he sent to the butcher at once, unless they are 

 specifl.lly valuable and are not badly affected. If kept, they must not he 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 aud 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 and hares must not be allowed to in- 

 troduce the eggs. 



The most prolific source of introducing parasites is in the introduc- 

 tion of infected sheep, and purchascirs should learn all they can of the 

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



(4.) All heavy and 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 aud salt (or both) should be spread over the ground at the 

 proper season to destroy the embryos, the cysts of the fluke, and also the snail which 

 acts as host. 



After draining, such fields should be cultivated and suitable crops 

 raised on them. 



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

 more fluke-germs will they pick up. 



