H. E. Durham 
a considerable resistance to infection with the nagana trypanosome, yet 
they are not solidly immunised by apparent recovery from oue attack. 
Relation of Birds to Nagana. 
In our joint report the fact is recorded that we were unable to 
infect pigeons with nagana ; this has been confirmed by other writers, 
for instance Laveran and Mesnil. 
It seemed possible that other kinds of birds might have a different 
reaction, and having obtained a kestrel (Falco tinnunculus ), I inoculated 
it in the breast with citrated rat’s blood, which swarmed with Nagana 
trypanosomes. The injection, about 2 c.c. in bulk, was given on 
10. XI. 98. Twenty days later (1. xil.) the breast was punctured, and 
two rats were inoculated with the blood that was obtained, although 
no recognisable trypanosomes were to be seen. One of these rats died 
on the 12th day with trypanosomes in its blood and great enlargement 
of the spleen ; its death, however, was complicated with a septic inflam¬ 
mation of the pleura. The second rat died on the 13th day, apparently 
of uncomplicated nagana, its blood was teeming with the parasites and 
the chief enlargement of the lymphatic glands corresponded with the 
site of injection (right thigh). 
On 11. xil. the blood of the kestrel was again examined both locally 
from the breast and from the foot, but nothing that could be recognised 
as trypanosomal was found. Two more rats were injected with blood 
from the breast on this day, 31 days after the original inoculation of the 
bird. Both these rats succumbed to nagana ; one was killed on the 
11th day with teeming masses of trypanosomes in its blood ; the other 
died on the 16th day. In both the chief glandular enlargement was in 
the right inguinal region, corresponding to the inoculation in the thigh. 
On 24. ii. 99 two more rats were inoculated, but they died after 
24 and 48 hours of septic mischief. 
On 6. HI. 99 two more rats were injected with blood from the bird’s 
breast. One of these died 35 days later without signs of infection by 
nagana, the other survived. 
A reinoculation of the bird was performed on 25. IV. subcutaneously 
in the breast with about 1 c.c. of highly infected citrated rat’s blood. 
On the next day only bird’s and rat’s red blood corpuscles, haemoglobin 
crystals and leucocytes could be found in a sample removed for in¬ 
spection. Fifteen days later a rat was inoculated with blood from the 
breast, the result was negative. 
15—2 
