Leaving the Government post on the Amala river, at an altitude of 5,500 feet, on 25th July, I moved down the west bank of the river and camped at a spring known as Ol-otu-lomot, at an altitude of 5,200 feet (see accompanying sketch-map). The next day I moved further down the river in search of an old Masai native, by name Ol-botor-ol-joni, who was reported to be familiar with the places in which tsetse-fly (Endorobo of the Masai) was to be found. I found this old man at the place marked on the map and camped there at an altitude of 5,100 feet.