GAME ANIMALS TO DISEASE IN AFRICA 15 
such insects are entirely dependent upon or associated with 
antelope and other game animals. 
It was formerly believed that in Africa the only carriers of 
any trypanosome belonged to the genus Glossina or tsetse flies, 
and that of these only the one species Glossina palpalis was 
capable of transmitting the human trypanosome of sleeping 
sickness. 
It is unnecessary here to go into the details of the numerous 
experiments and discoveries which have gradually dispelled 
this illusion, and it will be sufficient to say that — 
(i) In Rhodesia Glossina morsitans has been proved to 
transmit the human trypanosome causing sleeping 
sickness in that country ( T . rhodesiense, a separate 
species from T. gambiense of Uganda) ; 
(ii) while the genus Stomoxys has been proved to transmit 
a trypanosome in Mauritius and the Philippines, 
and in ‘ Sleeping Sickness Bulletin,’ No. 85, p. 117, 
it is pointed out that ‘ There is now not inconsiderable 
evidence from several parts of Tropical Africa that 
domestic animals may, in the absence of tsetse, 
become infected with trypanosomes pathogenic to 
them. Since other species of biting flies are in such 
cases present, it is suspected that these are the carriers. 
The flies incriminated are species of Tabanus, Hcema- 
tojpota, Stomoxys, Pangonia , and Lyperosia .’ 
Besides this it will be remembered that it has already been 
mentioned that trypanosomes have been found in almost all 
parts of the world, and as the tsetse flies ( Glossina ) are confined 
to Africa and a corner of south-east Arabia, it is obvious that in 
other countries the transmitting agents, many of which are 
now known, must be blood-sucking insects other than tsetse 
flies. Experiments to settle this question are badly needed, 
but there is at present great difficulty experienced in keeping 
the above-mentioned species of blood-sucking flies alive in 
captivity, and until this difficulty is overcome and satisfactory 
transmission experiments carried out, the question of what 
insects are concerned in the transmission of trypanosomes 
will remain uncertain. There is, however, sufficient evidence 
already to show that tsetse flies are not the only blood-sucking 
