Several months' constant traveling in the “proclaimed area” has led the writer to conclude that it contains at least four “primary centres” which harbour tsetse-flies, situated as shown on the map as follows:

No. 1, opposite Rifu, near Patsanjoka Marsh ;

No. 2, W. & S.W. of Kuti Marsh ;

No. 3, at Nyansato near the Chitawa Marsh ; and

No. 4, along and on each side of the Lingadsi River, between Long. 38° 8′ and 34° 13′ E.