352 
PLEURO-PNEUMONIA IN AUSTRALIA. 
Mitta River, in the vicinity of which the disease had been 
found. The Messrs. M,Laurin deny any knowledge of the 
existence of the complaint about the Mitta Mitta, when their 
cattle were removed ; and they advance as a reason why they 
could not have been infected at the time, that three or four 
hundred head left behind on the run have not even yet exhi¬ 
bited the slightest symptoms of disease. 
We are not at all disposed to doubt the perfect truthfulness 
of these statements, but still we are of opinion that they are 
not conclusive against the assumption that the disease might 
possibly have been introduced into the Yarra Yarra herd in 
this way. Pleuro-pneumonia was, about the time of the 
removal of Messrs. M^Laarin's cattle from the Mitta Mitta 
station, discovered very near to it; and it is possible, there¬ 
fore, that the seeds of the disease may have been sown amongst 
them before they left, which might have required some time 
for development. It was not necessary that the whole herd 
should have been infected in the first instance. It would 
have been sufficient that one or two infected beasts had been 
taken to Yarra Yarra. The dissemination of the disease 
might, no doubt, be accelerated by the usage the cattle sus¬ 
tained, by being tailed closely during the day, and pent up 
together in very wet yards, and in cold weather during the 
night, for a length of time. The cold would predispose to 
an inflammatory state of the lungs, and the close intercourse 
would render the disease more easily communicated. 
On the other hand, we are free to admit that there are many 
other ways in which the disease might have been introduced 
into this herd. The Yarra Yarra station is bounded by the 
Great Southern Road for six or eight miles ; and before the 
Cattle Disease Prevention Act came into operation, teams of 
working bullocks from Victoria travelled in that direction in 
considerable numbers, and probably camped on the run. 
Some of these might not only have been infected, they might 
have died of the disease on the very station. The pasture 
might have become infected with the malignant saliva, the 
surrounding atmosphere contaminated with the malaria. 
Stray beasts, too, from the numerous herds of store cattle 
taken into Victoria from this colony might, in their effort to 
return to their old runs, have passed over the station, or even 
remained on it to communicate the evil. 
Besides, we have been informed that a working bullock, 
which had been brought from Victoria in a team to Albury, 
just before the Act came into force, had strayed on to Messrs. 
M‘Laurin ? s run, and that this bullock, when slaughtered with 
their cattle, was found to be infected with chronic pleuro- 
