Much of the first part of this paper is in the nature of a continuation of the work previously published by the author. (Bull. Ent. Res., xxi, 1930, pp. 201–256). For this reason only a brief description can be given of the locality, vegetation, game, and fly-round methods ; those desiring a fuller knowledge on these subjects are referred to the above-mentioned paper. Again, a certain amount of repetition has been unavoidable. Some results obtained from only one year's observation have now been confirmed during a period of four and a-half years, and so have been given again. It is felt that this repetition is justifiable as the results in question are of special value, in that they are derived from four and a-half years continuous observation upon the same fly-belt, the method employed being constant throughout the whole period.The writer is in charge of Kikori Entomological Station, which he opened in March 1928 ; nine months later he was joined by his assistant Captain V. A. C. Findlay.The native village of Kikori is situated at the foot of the Masai escarpment, which bounds the Masai Steppe on the west. Kikori lies about 45 miles north of Kondoa-Irangi (the principal centre of the district), its approximate bearings being Latitude 4° 21′ S. and Longitude 33° 19′E. ; its elevation is 4,158 feet above sea-level.