TRYPANOSOMES IN TSETSE-FLIES AND OTHER DIPTERA. 227 
“Monkey 478. 
“Sept. 14th, 1905.—Inoculate this animal subcutaneously 
with 15 c.c. of cerebro-spinal fluid from a case of sleeping 
sickness, ‘Sengoma.’ ‘Trypanosomes are numerous in the 
fluid. — 
“Sept. 26th.—Trypanosomes have appeared in this animal’s 
blood to-day for the first time. 
“Oct. 15th.—Trypanosomes numerous. 'T'welve flies fed 
on this animal to-day. 
“Oct. 19th.—Trypanosomes numerous. ‘Twenty flies fed 
to-day. 
“Noy. 12th—Trypanosomes numerous. Twenty flies fed 
to-day. 
“Nov. 27th.—Died this morning. Trypanosomes nume- 
rous in the blood. One trypanosome seen in a smear of the 
brain. Glands and spleen somewhat enlarged. Stomach 
surface shows a few minute black ulcers and several nematode 
worms. Lungs, heart, etc., are normal.” 
“Monkey 507. 
“ Oct. 17th, 1905.—Inject the intestinal contents, with a 
few drops of normal citrate solution, of one Glossina 
palpalis subcutaneously into this monkey. ‘This fly had fed 
on Monkey 478 some forty-six hours previously and was found 
on dissection to be swarming with trypanosomes (see p. 234). 
“ Dec. 5th.—This animal’s blood has been regularly exa- 
mined twice a week up to the present, but trypanosomes 
have never been found.” 
I begin the systematic record of my observations with the 
batch of July 31st, 1905. Previous to that date, however, | 
had made various tentative experiments and observations on 
the infection of the fly and on the changes of the trypano- 
somes in it, which I do not propose to record in detail. 
Batch of July 31st, 1905.—The object of this experi- 
ment was to determine the changes undergone by I’. gambi- 
