342 
Col. Sir D. Bruce and others. Infectivity of [Nov. 23, 
Table [I11—Transmission of Trypanosoma gambiense from Sleeping Sickness 
Patients, Class B, to Healthy Monkeys, an Interval of Time being 
allowed for the Development of the Trypanosomes in the Fly. 
No. of : No. of No. of No. of 
experi. | Duration of No. of | gios fed on days flies | days flies Ranaces 
P treatment. | doses. fed on fed on ; 
ment. patient. : 
patient. | monkey. 
1993 7 days . 2°71) 4 100 4 50 ~ Monkey remained 
healthy. 
2091 eee 2 50 5 50 - 5 
2094. (aa 2 60 5 50 _ > 
2170 We &: 2 60 6 50 _ 5) 
Nyse |) sur 4 100 5 50 ee ie 
1987 30° 5, 4 65 5 50 — me 
| 1997 30° ;, | 4 90 4 50 _ 4 
| 2068 30, | 4 65 6 50 - 3 
2070 Ob aes 4 80 6 50 — fi, | 
2107 SON; 4 65 6 50 _ E 
2195 SO e, 4 50 6 50 — hd 
| 2348") Va0. 4 65 4 50 & 
2096 1 year 8 60 5 50 — J, 
2109 148s 9 65 5 50 — Bs 
2172 Last 8 60 5 50 _ e 
2193 are 9 60 6 50 — i" 
2254 21 years ? 80 | 4 50 ~ 
2256 22 Ae ? 60 4 50 — = 
2258 She Mo sie 60 4 50 _ 5 
1943 Nil peal 65 6 | 50 — 3 
1957 i ees 100 4 | 50 = . 
1967 x ala. 110 6 | 50 — 55 
| 2048 5 ine 50 6 50 —- | * 
| 2280 A 3 130 4 50 + T. gambiense ap- 
| peared in blood. 
2298 - Ns 80 3 50 + 55 
Remarks——In Table III, Class B, 25 experiments from 19 different patients are recorded. 
Six of these were from untreated cases. 
Sleeping Sickness was transferred from two untreated patients to normal monkeys. The flies 
belonging to these experiments were not dissected. 
The remaining four experiments from untreated cases were negative, both as regards infection 
of the flies (190 dissected) and the conveyance of the disease to monkeys. 
Of the 19 negative experiments from cases under treatment, four were from two patients who 
had been under treatment for one week. They had each received two injections of soamin in 
l-gramme doses, combined with 0°02 gramme of perchloride of mercury. Eight experiments 
were from patients who had been one month under treatment. They had each received four 
injections (soamin 1 gramme, and perchloride of mercury 0°02 gramme, per dose). Four experi- 
ments were from two cases who had been under treatment for 11 months. One of these had 
received injections amounting in all to soamin 8 grammes, HgCl, 0°10 gramme, and orpiment 
2 grammes. ‘The other patient had received a total amount of soamin 9 grammes, HgCl, 
0°10 gramme, and orpiment (?). Two experiments were from patients who had been under 
treatment for two and a-quarter years. They had each received a total quantity of drugs 
amounting to atoxyl 19°7 grammes, HgCl, 0°06 gramme, orpiment 4°60 grammes, and soamin 
4 grammes. One experiment was from a patient who had been three and a-half years under 
treatment, and had received during the last 18 months atoxyl 9°5 grammes, soamin 7°5 grammes, 
and orpiment 4°6 grammes. 
From these 19 negative experiments 509 flies were dissected between the 4th and 52nd days 
after their last infected feed. No flagellates were found in any of them. 
By 
