150 First Report on Economic Zoology. 



Nairobi, 



East Africa Protectorate, 



3rd September, 1901. 



To Sm Chaeles Eliot, K.C.M.G., C.B., 



His Majesty's Commissioner and Consul General, Mombasa. 



Sm, — I beg to acknowledge receipt of a copy of the correspondence 

 re Tsetse-fiy and tbe preservation of the Buffalo which you forwarded to 

 nie for my opinion, and I have the honoiu' to transmit to you herewith my 

 observations on the subject. 



The Tsetse-fly belt of British East Africa, exclusive of Jubaland, may 

 be said to extend from Mtoto Andes to Simha, a distance of roughly ninety 

 miles ; it is situated in a densely wooded, low-lying part of the country, 

 about 3000 feet to 3100 feet above sea level. 



Driajani, an old camping ground, within this area, was considered by 

 the late Captain Haslam and myself to be the most dangerous place for fly, 

 on the old transport route, but strange to say it was practically devoid of 

 game of any kind. 



In my opinion, Buffalo and other big game are not the only factors in 

 the Tsetse-fly theory, and we must first consider the question of climate 

 and humidity before we condemn the Bos caffa as the true and only source 

 of the Tsetse-fly and Tsetse -fly disease. 



I believe that the distribution of the fly is entirely influenced by the 

 physical aspects of the country and that for its existence it must have a 

 humid, low-lying position. 



Major Bruce in his excellent report says (see p. 20. Further report 

 on Tsetse-fly disease in Zululand, 1896), "That the presence of wild 

 animals in the vicinity of horses and oxen is not the only factor in the 

 problem is shown by the fact that in the old days when big game was 

 numerous and roamed over the whole country, hunters and travellers 

 never complained of fly until they encountered the disease in low-lying 

 tracts of country or along the large river valleys." 



As in the Hermansdorp district of Cape Colony herds of Buffalo are 

 still to be found, yet Tsetse-fly with its concomitant disease is unknown, 

 so in the high altitude of the Kedong (GOOO feet), in this Protectorate, 

 herds of Buffalo are to be met with, greatly reduced in numbers by rinder- 

 pest within recent years it is true, yet neither Tsetse-fly nor Tsetse-fly 

 disease have ever been known to occur, nor has the fly or its disease been 

 heard of in the Baringo district of the Uganda Protectorate, where herds 

 of Buffalo and other big game exist. 



When studying the causes which rendered the Island of Mombasa 

 uninhabitable for horses, I ascertained that an organism, the morphology 

 of which was identical with that fuund in animals suffering from Tsetse-fly 

 disease, was found in donkeys which had never left the island. 



I expressed an opinion then {vide Preliminary Report as to the causes 

 which rendered the Island of Mombasa uninhabitable for horses in ISOO) 

 with regard to African Nagana and Indian Surra being one and the same 

 disease, and as the occurrence of Surra cannot be attributed to the presence 

 of wild animals or Tsetse-fly, we must explain, ere we destroy the buffalo 

 in an attempt to stamp out Nagana, why a disease identical mth that 



