MODES OF \RUBEREULAR, INFECTION” IN 
WILD ANIMAS? IN GCAPTIVIFY. 
By WeyREID BEAIR, D:V.S. 
I N the absence of the more positive information which one 
acquires from a long series of experiments designed for the 
purpose of ascertaining the priority and manner of invasion of 
tuberculosis, much of this information regarding the progress 
of the lesions has been gathered from post-mortem examinations 
of natural cases. This is particularly the case in animals whose 
price has prevented them from figuring largely in experimental 
pathology. 
As the existence of tuberculosis is determined by the pres- 
ence of tubercle bacillus which produces the disease, conse- 
quently it is only since the characters of this were made known 
that we have been able to make an absolute diagnosis in suspected 
cases. . 
The identity of tuberculosis in human beings and that of cer- 
tain animals, and the possibility of one infecting the other, renders 
this disease of the greatest importance. 
The great difficulty in determining when the animal first 
becomes tuberculous makes it practically impossible to prevent 
the possibility of infection to its companions. Particularly is 
this danger greater among primates, where it is necessary to 
confine from 6 to I0, or even more, in one cage. 
ANIMALS AFFECTED. 
While it is quite safe to say that hardly any animal possesses 
absolute immunity from tuberculosis, certain species and indi- 
viduals are undoubtedly less susceptible than others. 
My investigations from necessity have been confined to the 
animals in the primate collection, owing to the fact that with 
one or two exceptions the animals in the Park outside the pri- 
