332 Col. Sir D. Bruce and others. Domestic Fowl of |Nov. 12, 
Table IT. 
Days of ewe Result of 
‘“eycle” | Experiment | No. of me eh inoculation of | 
Date. the flies No. of Aj oe perigee oe fowl’s blood 
fed on fowl Hed alse PETE 1 Ue into normal 
: fective ? 
fowl. s monkeys. 
1910. 
May 9—21 ...... 7—19th Cock 2455 50 NO A080 ore Negative 
| GIO &, 4—22nd » 2471 60 Yes (18 p. c.) ¥ 
, 16—June 1 7—238rd 5 Ato 95 Pe Oe We oa) 59 
PPG | aot , 2480 55 » (15 p.e.) a 
June 2—11......... 10—19th » 2518 100 une aman 5 
tS DE, eae) 5—17th , 2519 100 ee. - 
age Si ieee Ae 8—23rd 2519 100 | Yes (8°8 p. ¢.) 5 
Se 5 lyk pt 11—20th 2519 100 pita cee | ‘ 
Remarks.—The chief criticism against these experiments is the fact that the flies fed on the 
fowls during the earlier days of the experiments, when the Glossina palpalis are usually not 
infective. However, as results have been recorded by the Commission where Glossina palpalis 
have infected susceptible animals as early as the 18th day of an experiment, it has been decided 
to publish these experiments. 
Can Fowls Transmit the Virus of Sleeping Sickness to clean Laboratory-bred 
Glossina palpalis? If this is possible, can the Flies so Infected convey the 
Virus to Normal Susceptible Aiimals ? 
In view of the results obtained by the first series of experiments, 16 would 
seem somewhat unnecessary to follow this question further. 
It has so far been proved that the blood of fowls which have been fed upon 
by infected Glossina palpalis is non-infective when injected into susceptible 
animals. It has now to be ascertained if the blood of such fowls is also 
incapable of infecting the fly. This would constitute additional evidence 
against the fact that fowls act as a reservoir of 7rypanosoma gambiense. 
Cages of laboratory-bred and laboratory-infected Glossina palpalis, which 
were known to be infective, were fed on fowls for a varying number of days. 
Next, clean laboratory-bred flies were fed on these fowls for several days. 
The flies were then fed on normal susceptible animals (monkeys), in the 
endeavour to infect such. animals with Z’rypanosoma ganbiense, and so prove 
that the blood of the fowl was infective. The full details of three experiments 
are given below :— 
