278 EELATION OF BIG GAME TO FLY-DISEASE. 



" The result of my examination up to the pi-esent of the 

 Tsetse-fly is briefly this ; — 



" Immediately after feeding, the tube of the proboscis can be 

 seen to be crammed full of red blood corpuscles, among which the 

 hjeraatozoa can be seen actively wriggling. Up to 46 hours 

 after feeding I have seen living hjematozoa and red blood 

 corpuscles in the proboscis. After 118 hours the hsematozoa are 

 still Very numerous and A'igorously active in what remains of the 

 blood in the stomach. After 140 hours the stomach is empty. 

 After 25 and 70 hours I have seen many motionless hsematozoa 

 in the faeces, but I have never seen at any time any appearance 

 of life in the hcematozoa in the fteces or contents of the lower 

 part of the intestine. The pai'asites appeared, however, un- 

 changed in form, and I intend making some injection experiments 

 with the fseces to find out if these motionless hsematozoa have 

 any vitality left in them" (p. 19). 



Pages 19 to 24 are devoted to the second part of the account 

 of the etiology of Nagana, viz. : — 



" B. — Relation op Big Game to the Fly Disease. 



" As we have found that the Tsetse-fly in a state of nature 

 does act as a carrier of the hasmatozoa of Fly Disease, it is evident 

 that it must procure the parasite somewhere, and what more 

 natural than it should procure it from the blood of warm-blooded 

 animals living in the Fly Country ? 



"It is not necessary to suppose that in these animals Nagana 

 is a fatal disease, but only that the big game harbour the' 

 parasite which causes the disease for a longer or shorter time 

 with little or no disturbance to health. We have seen, as in the 

 case of the heifer mentioned on page 33, that cattle may have 

 the parasite in their blood for at least eighteen months without 

 causing death, and it is possible that some of the big game die of, 

 this disease. When in the Fly Country quite lately, I chanced 

 on a dead wildebeeste surrounded by vultures. The skin of this 

 animal was quite intact and showed no signs of its having come 

 to a violent death. It was somewhat emaciated and had the' 

 appearance of an animal dead of Nagana. I did not inject any 

 blood from it into a susceptible animal, as it was in a state of 

 decomposition" (p. 19). 



" In regard to this relation of big game to the Fly Disease, 

 there can be no question as to the very widely spread opinion 

 which exists regardmg the wild animals as in some way or other 

 responsible for its propagation, and in this connection the buflalo, 

 wildebeeste, quagga, waterbuck and koodoo are usually named. 

 Europeans and natives in all parts of the country are found who 



