1910. | Reservoir of the Virus of Sleeping Sickness. 317 
fable ©. 
= No. of days Result. | 
No. of 2 iil No. of days | 
experi-| eae infected ee , ; 3 Remarks, 
a | aed appeared. | Positive.| Negative. 
| | 
2328  Bush-buck 5 | — i oes Trypanosomes never seen. | 
2357 | Reed-buck 12 25 + | 
2359 | ks | 6 Korea a5 ie 
2371 | Bush-buck 8 bab i 
2372 | ‘ | 6 | 8 + 
2378 Water-buck 8 | _ + | Trypanosomes never seen. 
2427  Reed-buck 6 7 + | | 
2428 Bush-buck 13 — + | _ Trypanosomes never seen. 
2429 | Reed-buck 8 9 + 
2431 i | 6 fe pele ona 
2445 : i. | 7 | 8 + | 
From these experiments it is shown that antelope may be readily infected 
with Sleeping Sickness by the bites of artificially-infected tsetse flies. 
Eleven antelope were used, and in every case a positive result was obtained. 
It will be remembered that in similar experiments made with cattle the 
same result was obtained. 
2. If Antelope can be Infected with the Virus of Sleeping Sickness, can they 
| Transmit the Infection to Clean Laboratory-bred Glossina palpalis when 
these Tsetse Flies are allowed to Feed upon Them? Further, of these 
Glossina palpalis become infected, can they transnit the Virus to 
Susceptible Animals ? 
It has now been proved that water-buck, reed-buck, and bush-buck can 
be infected with the virus of Sleeping Sickness, with what would seem to be 
unfailing regularity. Should, however, these antelope be incapable of 
infecting the Glossina palpalis with Trypanosoma gambiense, the fact is of 
academic importance only. On the other hand, should the results of 
feeding clean laboratory-bred Glossina palpalis on these infected buck give 
positive results when these flies are subsequently fed on normal susceptible 
‘animals, a further step has been made in the search for a reservoir of the 
virus of Sleeping Sickness, other than man and his domestic animals. 
The method adopted to test this second query was carried out as follows :— 
Clean, laboratory-bred Glossina palpalis were fed for several days on an 
infected buck. After an interval of starvation of 24 hours or more the flies 
were transferred to healthy animals and fed daily. When the healthy 
animal showed Trypanosoma gambiense in its blood the experiment was 
Stopped, and the surviving flies were dissected as soon as possible. 
