PRIZE ESSAY 
335 
first inoculation killed rabbits by anthrax, and later when the bac- 
teridies disappeared, the microbe resisting, the same blood killed 
hens with all the lesions of cholera. In some animals, on the 
contrary, such as dogs, sheep and guinea pigs, the bacteridies 
resist the most; the septic microbe is eliminated, and it is always 
by anthrax that those animals died when inoculated with that 
blood. 
Mortal septicaemia shows itself even in animals which have 
not been inoculated, but which have taken septic virus through 
digestive apparatus; the inoculation lias then taken place through 
lesions of the buccal or guttural membrane. In the point of view 
of general prophylaxy this is an important discovery.— Revue 
dh Hygiene. 
PRIZE ESSAY. 
By J. T. Duncan, V.S. (Toronto.) 
CONTAGIOUS DISEASES OF CATTLE. 
I. PLEURO-PNEUMONIA CONTAGIOSA-INTRODUCTION. 
In treating of the contagious diseases of cattle, the one men¬ 
tioned above demands our first attention ; not only on account of 
the enormous injury it is capable of inflicting on the stock inter¬ 
ests of any country to which it is brought—not only because of 
the prominence given to it by recent events, but because of the 
facility with which it may be introduced into a country at present 
free from it. This it is which gives to Canada such a vital inter¬ 
est in the disease. W"e are, and have been, free from its ravages. 
So long as we remain so, our trade in cattle (now one of the most 
lucrative and important to the country) will not be subjected to 
annoyance and loss by legislative interference. While the United 
States, by gross govermental carelessness, have allowed it to be¬ 
come firmly established in their borders, we are enjoying the ben- 
