134 NEW YORK ZOOLOGICAL SOCIETY. 



mates have been free from this disease. The experimental work 

 along this line is not complete, but the facts already gathered 

 are of importance. 



The examinations were conducted as follows : As soon after 

 death as possible the animal was opened, the trachea from larynx 

 to bifurcation was ligatured at each end and removed. Smears 

 and scrapings were then taken under sterile conditions from mu- 

 cous membrane, 5 to 6 slides used in each instance. A like num- 

 ber of specimens were taken from the nostrils under the same 

 conditions at the same time. Smears were taken from the living 

 animal by the means of small cotton swabs applied to the mucous 

 membrane of the throat or nostrils. 



Smears taken from the nostrils of suspected cases and those 

 that showed no clinical signs whatever, were interesting in dem- 

 onstrating that at one time the bacilli were present in great num- 

 bers, while at other times (intervals of one or two weeks) we 

 find them few in number or wholly absent in the same animal, 

 hence it would seem that too great reliance cannot be placed on 

 the occurrence of bacilli in the nostrils as indicating a diseased 

 animal, for in several instances bacilli were found in the secre- 

 tions from the nostrils when on careful autopsy no evidences 

 of tuberculosis were found. The bacilli were found to be fairly 

 constant in advanced cases of pulmonary lesions where breaking 

 down of tissue was a distinct feature. Coughing is rarely present 

 among these animals, even in the most advanced cases, but sneez- 

 ing is quite frequent even in health, and this, it seems to me, is the 

 most prolific source of dissemination of the contagium. Since 

 the bacilli when dried may be carried by currents of air it is 

 not necessary that healthy animals should come in direct con- 

 tact with the tuberculous cases to become infected. 



Without the Bacillus tuhercnlosis the disease cannot be con- 

 tracted even by the most weakly animal, but it is equally true 

 that with its presence in a building or in the body of a com- 

 panion the strongest is not absolutely free from the danger of 

 contagion. Notwithstanding the frequency of extensive pul- 

 monary lesion, the trachea, larynx, and pharynx are seldom af- 

 fected with tuberculosis in these animals. I found lesions in the 

 larynx in only one instance, but in three cases discovered an 

 occasional bacillus within the epithelial cells lining this organ. 

 Some appeared to be in process of degeneration. The bacilli 

 were never in sufficient numbers to give rise to any distinct 

 lesions. Two of these cases had no lesions of tuberculosis pres- 

 ent in any part of the body on examination. This fact would 



