causing Disease in Man in Nyasaland. 



207 



In making up the average incubation and duration, mixed infections are 

 not included. It must be admitted that these averages are only approximate, 

 as it is impossible to deal only with animals of the same age, weight, health, 

 and powers of resistance. Dogs, for example, fall away very much during 

 the rains, when biting flies and ticks are numerous. 



Table II. — The Average Duration, in Days, of the Disease in Various 

 Animals caused by the Wild-game Strain of the Trypanosome causing 

 Disease in Man in Nyasaland. 





Goat. 



Monkey. 



Dog. 



White rat. 



Average duration, in days 



46 



38 



41 



32 



No. of animals employed 



5 



9 



13 



6 



Compare this with the following Table : — 



Table III. — The Average Duration of Life, in Days, of Various Animals 

 infected with the Human Strain of the Trypanosome causing Disease in 

 Man in Nyasaland. 





Goat. 



Monkey. 



Dog. 



White rat. 





42 



2o 



24 



30 





29 



20 



25 



21 



Table IV. — The Percentages of Eecoveries in Various Animals infected with 

 the Wild-game Strain of the Trypanosome causing Disease in Man in 

 Nyasaland. 





Goat. 



Monkey. 



Dog. 



White rat. 





















No. of animals employed 



5 



9 



13 



6 



Compare this with the following Table : — 



E 2 



