causing Disease in Man in Nyasaland. 



43 



Baboon. — Only one was inoculated and it proved resistant. 



Monkey. — Twenty monkeys died, on an average, in 25*8 days (10 to 51). 

 The trypanosomes were always present in the blood and were often numerous 

 or very numerous. In none of the monkeys was oedema of the face or corneal 

 opacity noted. 



Dog. — Twenty-five dogs were inoculated. All died, on an average, in 

 34*3 days (14 to 78). The parasites were always present on microscopical 

 examination of the blood, and were often numerous and very numerous. 

 In eight of the 25 dogs, opacity of the cornea and swelling of the face were 

 present. 



Babbit. — Seven rabbits died, on an average, in 27 - 9 days (15 to 42). A 

 rabbit suffering from this disease presents exactly the same clinical picture as 

 that seen in rabbits suffering from Nagana. There is first swelling round the 

 eyes ; then the face puffs up, and sores break out round the nose and the eyes. 

 Next there is thickening of the ears, which eventually also become covered 

 with sores exuding a serous fluid. Towards the end the eyes are completely 

 closed up, the nose much swollen, and both eyes and nose discharge a 

 purulent fluid. 



Guinea-pig. — These animals are more refractory than rabbits, and often 

 require to be re-inoculated before they take the disease ; 15 were used. They 

 died, on an average, in 66'6 days (13 to 114). No prominent symptom, such 

 as oedema or corneal opacity, was seen. 



Bat. — -Twenty-one were inoculated and died, on an average, in 30"3 days 

 (13 to 93), with their blood swarming with trypanosomes and their spleens 

 enormously enlarged. 



Comparison of the Five Human Strains of the Trypanosome causing 

 Disease in Man in Nyasaland, in regard to their Virulence 

 towards Various Animals. 



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

 Animals. The letter E means that the animal is refractory, that is, 

 not susceptible to the disease. 



Strain. 



Ox. 



Goat and 

 sheep. 



Baboon. 



Monkey. 



Dog. 



Rabbit. 



Guinea-pig. 



White rat. 



I 



134 



34 



R, 



30 



24 



42 



52 



21 



II 





59 





16 



32 



33 



95 



44 



III 





31 





18 



42 





62 



22 



IV 





37 





39 



33 



15 



57 



49 



V. 





60 





25 



42 



28 



102 



32 



