184 



BOVINE PATHOLOGY. 



liver, for instance, found filled with enormous cysts, being 

 thereby much enlarged and deformed, and with compara- 

 tively little secreting substance remaining. These parasites 



Fig. 26. — Tcsnia eckinoccoccus. A. Mattire form, 

 or scolex of cyst (Cobbold). 



B. Tajnia head 



have been observed in many parts of the body, even in bones; 

 they seem to prefer protected situations, as parenchymatous 

 or soft viscera. Dogs, foxes, and other canine bearers of 

 Tania echinococcus pass the segments of that parasite 

 with their fsBces, and thus act as diffusers of this disorder. 

 Parts containing the cysts should never be given to dogs, 

 but destroyed. Intimate association of dogs with cattle is 

 related to prevalence of this disorder. The eradication of 

 this disease is of great importance, as it causes a certain 

 mortality among human beings, especially in Iceland. 



In concluding our notice on specific blood d'iseases, we 

 must observe one remarkable argument in favour of the 

 hypothesis of their parasiticnature. As methods of research 

 have improved diseases previously classed among the exan- 

 themata have been traced to animal or vegetable parasites ; 

 favus and scabies prove this. Hurtrel d^Arboval was only in 

 accordance with his times when he gravely discussed the 

 value of vaccination as a preventive of the latter disorder. 



