BOVINE TUBERCULOSIS. 
427 
pleura, or on the periphery of the lobules in the interstitial cel¬ 
lular tissue. 
It is likely that each tubercular focus was formed around a 
phagocyte of the bronchial mucosa absorbed into the lymphatic 
circulation after having absorbed one or several Koch’s bacilli. 
3d. The mucous membrane of the mamma is very suscepti¬ 
ble to microbic infection and offers a very slight resistance to 
Koch’s bacilli, especially during lactation. 
These experiments and similar ones practiced on milking 
goats have demonstrated that of all the tissues of the living or¬ 
ganism, the mamma in a state of lactation makes a field best 
adapted to the growth of the tubercular bacillus. They show, 
also, but this is denied by some authors, the possibility of prim¬ 
itive tuberculosis in the mammary gland. 
They show finally how real is the tubercular intoxication. 
Cows 10 and 11, killed jlist before going to die, did not 
show any such organic lesion as could explain that deep 
cachexia which was causing death. With them the period of 
incubation was very short ; 3 days for cow No. 10 ; 13 days for 
cow No. 11. 
4th. The intravenal injection asserted itself, as it always 
does when a virulent bacillus is used, as the most severe and 
rapid method of infection, but no practical conclusion can be 
drawn from it, as tubercular infection never develops in that 
manner. 
5th. This observation is the last, and has a very practical 
import. 
On none of the animals experimented upon, no matter how 
short the period of incubation, or how rapid the evolution, the 
lesions had not undergone the mollification or the calcification, 
which is the rule, one may say, with all the tubercular bovines. 
To sum up our conclusions in reference to the two points 
aimed at by our society : 
1st. Whatever may be the means of contamination, there 
always elapses some time between the moment when the con¬ 
tagion has penetrated the organism and that where it manifests 
