1910.] Glossina palpalis Med on Sleeping Sickness Patients. 348 
Table [V.—Transmission of Trypanosoma gambiense from Sleeping Sickness 
Patients, Class C, to Healthy Monkeys, an Interval of Time being 
allowed for the Development of the Trypanosomes in the Fly. 
| | | 
No: of |) Nozot 
No. of ; ie No. of Byer: 5 
experi- Honea Gy Ole. eGatteniem| GER WEE | Claelbes Result. | Remarks. 
reatment. | doses. : fed on fed on 
ment. | patient. ; 
| | patient. | monkey. | 
21038 7 days 2 60 6 50 - Monkey remained 
| healthy. 
2168 (igor 2 63 6 50 = 33 
2250 (ome 1 100 4: 50 _ ‘ 
wez034 |. 30° ,, PI 100 3 50 + | gambiense ap- 
peared in blood. 
2098 30) 4 50 5 50 ~ Monkey remained 
healthy. 
2105 30, 4, 65 4 50 _~ 5 
| 2189 30 ,, 4 60 7 50 — 53 
| 2191 30 ,, 4 65 a 50 _ 
2244, 23 years i 120 4 50 — 3 
2242 Nil Nil 85 z 50 _ 35 
Remarks.—In Table IV, Class C, 10 experiments are recorded. One of these was from an 
untreated case with large numbers of trypanosomes in the cervical glands, but none detectable in 
the blood. 
The monkey was not infected by flies fed upon this patient, and so the flies were not dissected. 
Of the 9 experiments from treated cases, Class C, three were from two patients who had been 
under treatment for one week, of whom one had been given a single dose of soamin 2 grammes, 
and HgCl, 0°04 gramme. The other patient had received two doses. 
The experiments performed from these patients were negative as regards infection of both 
monkeys and flies. 
Three patients had been under treatment for one month. Each of these patients had been given 
injections of soamin and perchloride of mercury, amounting to 2 grammes of the former drug and 
0:08 gramme of the latter. One of these experiments was positive, both as regards infecting the 
flies and transmitting the disease to monkeys. 
Seventy-five flies were dissected from the positive experiment, 2034. Of these, four flies were 
found to be infected with Trypanosoma gambiense on the 28th, 39th, 40th, and 46th day 
respectively after their last infected feed. ‘The four flies found to be infected with trypanosomes 
were injected into a susceptible animal, which subsequently developed Sleeping Sickness. 
It is obvious that the results obtained from these experiments, though 
giving us some information, are insufficient to warrant a decisive answer to 
the questions before us. 
With regard to the first query: Can treatment of Sleeping Sickness 
patients by the drugs named influence the infectivity of the fly? Omitting 
the mechanical transmission experiments, we may say that out of the 35 
experiments only one produced a positive result, zc. flles were infected and 
the disease transmitted from a Sleeping Sickness patient under treatment 
to a normal monkey. The case referred to above will also entitle us to 
express an opinion as to whether one or more doses of a certain trypanocidal 
