INTRODUCTION 



At the commencement of 1910, when studjdng Tropical 

 Medicine at the London School, I was asked if I would 

 undertake an investigation into the bionomics of tho 

 Tse-tse fly, Glossina palpalis, in Uganda, as the Tropical 

 Diseases Committee of the Royal Society had come to 

 the conclusion that a greater knowledge of this fly was 

 essential for the successful dealing with the disease. 



I left England in June 1910, and during the second half 

 of this year and beginning of 1911 worked at Jinja, 

 on the north shore of the Victoria Nyanja,^ where the 

 Nile takes origin, and endeavoured to famiharize my- 

 self with the novel surroundings and with the fly. 



It soon appeared that residence on the completely 

 depopulated islands known as the Sesse Isles, in the 

 north-west part of the lake, would afford ideal conditions 

 for studying Glossina unaltered by the presence of man- 

 kind and his surroundings ; accordingly, in February 

 1911, I went to Nsadzi Isle, which, lying south of Entebbe 

 and within two or three hours of it by canoe, had been 

 recommended by the P.M.O. as suitable for a beginning. 

 This island, however, did not furnish aU the conditions 

 required for the investigations, and camp was moved, 

 after a fortnight, to the large Island of Damba to the 

 east and on the Equator, where the rest of the year was 

 spent. 



^ Nyanja, not Nyanza. The former is Luganda for lake, the latter 

 means nothing, and is erroneously copied from one book to another. 



