A Thousand Miles in a MachiUa 



a tsetse bite is fatal, producing a rot which causes 

 death. It is not this variety of tsetse, but glossina 

 palpalis, that habitually carries the sleeping sickness 

 germ. It has been ascertained — so we were told on 

 the voyage home by a doctor who had been for 

 sometime studying sleeping sickness — that glossina 

 morsitans and the ordinary mosquito can also carry 

 the poison. We gathered, however, that they both 

 retain the infection for a comparatively short time.^ 



One curious peculiarity about the tsetse is the 

 manner in which it will entirely abandon a district in 

 which it has once been prevalent. Mr. Selous gives 

 several instances of this in his works. The reason 

 for migration is a disputed point. The presence of 

 the tsetse is attributed by some to the vicinity of 

 certain kinds of game, and it is said that if the game 

 left the *' fly " would go with it. Whatever the truth 

 of this theory may be, it is not one that a sports- 

 man would wish to encourage, and it can hardly 

 be applicable to North- East Rhodesia, where there 

 was not a sufficiency of game to attract the 

 enormous quantity of '' fly " we at times en- 

 countered. 



There is one point, and one only, to be said in 

 favour ol glossina morsitans, and that is that it goes 

 to bed at night. This peculiarity frequently enables 

 valuable cattle to be driven with safety through the 

 *'fly" belts, which are well known. 



1 Quite recently sleeping sickness has appeared in the 

 Luangwa Valley. It has not yet been fully determined what 

 insect is the carrying agent. A Commission is being sent 

 out by the Chartered Company to investigate. 



154 



