136 NEW YORK ZOOLOGICAL SOCIETY. 
in my opinion, is not the common source of infection, but that 
intestines and abdominal organs are usually infected secondarily 
through the breaking down of tubercular deposits in lungs find- 
ing their way into bronchial tubes, finally reaching the throat, 
the animal swallowing secretion containing the bacilli in great 
numbers, some of which would doubtless escape the action of 
the gastric juices, pass on to the intestines, and if in sufficient 
number produce tubercular enteritis, or they might pass to 
mesenteric glands without producing any lesions whatever in 
the intestines. 
Experimental evidence apparently shows that a relatively large 
number of bacilli are necessary to experimentally infect healthy 
animals by ingestion. Probably if the mucous membrane be 
not intact a smaller number of the bacilli would suffice. 
The rarity or total absence of tubercular lesions in the stomach 
would indicate that the gastric juices possess power to prevent 
the growth of the bacilli. 
Specimen smears were taken from cesophagus at the middle 
and lower third. Although I have made numerous smears I have 
in only a few instances found the bacilli to be in great numbers, 
and in a large percentage of cases none were present. 
The method used in staining was that of Gabbets. After 
spreading the material in the finest possible film upon the glass 
slide a fluid composed of 100 grammes of a 5 per cent. aqueous 
solution of carbolic acid, and 10 grammes of absolute alcohol in 
which 1 gramme of carbo-fuchsin had been dissolved; a few 
drops of this solution was poured over the film side of slide and 
heated for two minutes, or until steam arose from the stain. It 
was then placed for about one minute in a mixture of 100 
grammes of a 25 per cent. solution of sulphuric acid in which 
2 grammes of methylene blue had been dissolved. It was next 
rinsed in alcohol and mounted in Canada balsam, microscopic 
examination with 1-12 oil emersion lens used. 
By this convenient method the bacilli appear red or pink, and 
the surrounding tissue blue or greenish in color. 
The fact that we are not at the present time seriously affected 
with tuberculosis is no reason why we should not take every 
possible precaution to prevent and to repress its further advance. 
