STATEMENTS BY BRADSHAW AND SELOUS. 39 



that any mere poison or venom should exist so powerful as to 

 cause the death of a large animal in such small dose." It will 

 be seen that in his first hypothesis Dr. Drysdale came very near 

 the truth, though Col. Bruce's investigations, with the subsequent 

 papers by Laveran and Mesnil [XXL], and Plimmer and Brad- 

 ford [XX.] on the life-history of Trypanosoma brucei, would seem 

 to show that the Tsetse-fly is in no sense its host : recent German 

 writers on Tsetse-fly disease, however, incline to the opposite 

 view. As we shall find, between this date and that of Col. 

 Bruce's memoir, vaiious writers published notes expressing practi- 

 cally the same view as Dr. Drysdale concerning the etiology of 

 Tsetse-fly disease. 



Captain J. F. Elton [59], writing in 1879, mentioned the 

 Tsetse as abounding near Livingstonia, at the south end of Lake 

 Nyasa ; * and in the same year Sir Rutherford Alcock [60] 

 stated that the Tsetse-fly " on the road to Mpwapwa " had 

 destroyed the draught cattle belonging to a party sent by the 

 London Missionary Society to Lake Tanganyika [Cf. 54]- A 

 note printed in the Proceedings of the Royal Geographical 

 Society [62] about the same time records the fact that bullocks 

 were working satisfactorily on the first section of the road then 

 being made from Dar-es-Salaam to the interior, and adds, " It is 

 therefore clear that there is no Tsetse-fly on the forty miles 

 already traced of the route. . . . " f A letter published in 

 " The Times," of February 25th, 1879, by Lewis Hornor [64] 

 recommends the Boer method of crossing fly-belts at night — a 

 mode of avoiding the attacks of the fly that, from the experience 

 of subsequent travellers, is not invariably eff"ective \_Gf. 77> HO]. 



Various books and papers [66-75] published during the next 

 two years (1880-1881), and dealing mainly with South Africa, 

 contain statements of the occurrence of the Tsetse-fly in ditferent 

 localities. 



Selous' " Hunter's Wanderings in Africa " [76], one of the 

 classics of South Afi'ican sport, and a paper on " The Tsetse Fly," 

 by Dr. B. F. Bradshaw [77], both of which appeared in 1881, 

 include many interesting details. The experience of both writers 

 had been gained in the same country, viz., the vicinity of the 



* Su- Harry Johnston [145], writing in 1897, states that the south 

 coast of Lake Nyasa is almost entirely free from Tsetse. 



t Cf., however [71], where it is stated that the Tsetse-fly occurs on this 

 road forty miles from the coast, rendering the employment of horses and 

 bullocks out of the question: "the belt of fly-country is, in fact, here 

 wider and more continuous than it is further to the north." 



