30 
Tuberculin Reaction in Monkeys. 
On March 1st, 1911, there were three monkeys left in 
the detention rooms for retesting. During the year we 
have received twenty-three new animals. During the 
previous year we had four deaths from tuberculosis, but 
early after the beginning of this past fiscal year several 
more monkeys died from the same disease. It was then 
decided to retest all the monkeys in the collection. The 
animals were brought to the infirmary in convenient 
groups, tested and returned to the outer cages. When 
the inside cages had been emptied, the whole inside of 
the monkey house was disinfected by formaldehyde gas 
and thoroughly washed. The monkeys were then re- 
turned to the inside exhibition cages. The whole num- 
ber of tests made during this year was 123, representing 
23 new and 50 old monkeys. Forty-three monkeys were 
tested two or more times. Our methods of handling 
the animals have been the same except that slightly 
larger doses of the tuberculin have been used. I find a 
more pronounced reaction with one and a half or two 
milligrams in the rhesus macaques and small baboons 
and usually the dose is doubled on secondary test. Of 
the twenty-three monkeys received this year two have 
died of tuberculosis and two without showing it. The 
other 10 dying from tuberculosis were passed before the 
first of March, 1911. Five of the twelve tuberculous 
animals died on exhibition, the remaining seven in the 
laboratory where they were returned for retesting or 
were detained for poor condition awaiting a further test. 
In the last report we described the history of Red 
Monkey No. 21. At the beginning of the year he was 
waiting for another injection and he was killed after this 
although his temperature record was not bad. His his- 
tory and association with infected monkeys were enough 
to condemn him. In the lungs and bronchial glands 
there were a few small fibro-caseous nodules about two 
or three millimetres in diameter. These contained a 
