SlEEPINTt RiPKNERS A\n the liAHP-FiE-ftHAE.VI, PnOVINrE 
Extracts from Captain Howarrl Ensor’s Report to tlie Snrlan Sleeping Sickness 
Commission (April, 1908). 
On behalf of the Sudan Sleeping Sickness Commission, Captain Howard Ensor, D.S.O., 
continued and extended the work begun by Major Dansey Browning. He traversed a large 
portion of the remote Bahr-El-Ghazal Province, and carried out important investigations 
often under great difficulties. The results of his expedition are incorporated in an 
interesting and useful report which, I understand, is to be printed and circulated. One 
need only, therefore, tabulate some of the facts of more general interest collected by 
Captain Ensor, while Mr. Archibald contributes a short paper on his Uganda experiences 
and observations. 
Colonel G-. Douglas Hunter, D.S.O., the President of the above-mentioned Commission, 
has kindly permitted me to reproduce the maps prepared by Captain Ensor, and the latter 
has been good enough to furnish me with information regarding his work. 
He deals first with :—• 
A. The Tsetse Flies of the Bahe-El-Ghazal Province 
Noting that only the two species Glossimt palpalia and Glossina morsitans were found by 
him. Major Dansey Browning, however, discovered what Mr. Newstead believes to be a 
distinct variety of the latter species. 
1. Bistrihution. The maps show the places where the presence of G. palpalis 
was noted, and Captain Ensor believes that this fly is to be found everywhere in the 
Bahr-El-Ghazal Province where the conditions necessary to its existence, i.e. deep shade 
near open water, are to be found. The palpalis areas exist for the most part along the banks 
of rivers, and in the province there are four riparian palpalis areas which begin at the Nile 
and Congo watershed, and extend to the north throughout nearly the whole extent of the 
province. Two of these, along the Sueh and Naam rivers respectively, are of the highest 
importance in connection with the question of the spread of sleeping sickness into the 
interior of the province, because the two principal roads connecting the southern districts 
with the centre of the province follow the courses of these rivers. The Arabic name of 
G. palpalis is given as “ Bihati El Marad Eit Noom,” the Fly of Sleeping Sickness, the local 
Zandeh name being “A''. G^mza.” 
G. morsitans is termed in Arabic “ Dihan El Marad El Hahim,’’ the Fly of the 
Cattle Disease, and locally in the Zandeh tongue is called “ Paij-a.” 
The more intelligent natives, therefore, clearly recognise the difference between the 
two species of tsetse fly. 
G. morsif.ans is extremely common in most parts of the Bahr-El-Ghazal Province and is 
very troublesome. The localities in which it is known to exist are shown on the map. It 
is responsilile for a heavy mortality amongst transport animals working along the roads from 
M’volo to Meridi, Meridi to the Bassumboru River, and from Khojali to Wau. 
2. JIahiU. (i) Of G. palpalis. It exists almost exclusively in the immediate vicinity 
of the open water of rivers and pools, and the shade afforded by large trees is, according to 
Captain Ensor, absolutely essential. He has never found the fly along the banks of water¬ 
courses destitute of trees, even though thick scrub and long grass, afforiling considerable 
shade, may be jiresent. 
G. palpalis is never found where the papyrus swamps prevail. 
This is due in part to the absence of foreshore and of shade, and more jiarticularly to 
the absence of dry ground in such places, for Caiitain Ensor has noticed that the fly, when 
Tsetse flies 
<7/ossif/a 
palpalis 
