1912.] Antelope and their Relation to Trypanosomiasis. 



163 



Ifc may in addition be pointed out in the case of Experiments 509-510 

 that both monkey and goat developed T. gambiensc — confirmed in the latter 

 by sub-inoculation into a monkey as well as in stained preparations ; more- 

 over, the goat was tethered in the camp some distance from the monkeys' 

 boxes. 



Since May, 1911, Dr. Carpenter has always had two monkeys in residence 

 in the boxes left by Hammerton and Bateman, and though examined from 

 time to time he has never had a case of spontaneous infection by stray flies. 

 The following is a brief history of the animals which serve as a control to 

 my experiments on Damba Island : — 



Monkey A. — Arrived Damba, May 1, 1911, and was immediately used to 

 test infectivity of wild Damba flies. Became infected on May 15, and was 

 immediately shot. 



Monkey B (into which the blood of Situtunga 402-3 was injected). — 

 Arrived Damba, May 25, 1911, and between then and September 25, when 

 the injections were made, a period of four months, was examined on 19 

 occasions, with negative results^ On October 2 was negative, and on 

 October 3 Dr. Carpenter first discovered trypanosomes in its blood. 



Monkey C. — Arrived Damba, May 29, 1911, and from that date was used 

 by Dr. Carpenter to test the infectivity of wild 67. palpalis from the neigh- 

 bourhood of Damba. It was examined on 36 occasions with no result during 

 the ensuing five months. On November 6 it became infected, having by 

 this time been fed upon by several thousands of wild fly. 



Monkey D. — Tame monkey kept by Dr. Carpenter, and exposed to all the 

 risks run by the experimental monkeys. Arrived Damba, March, 1911. In 

 perfect health up till October 9, 1911, when, at my request, it was first 

 examined. Since that date has been examined weekly, and has never shown 

 trypanosomes, and is in perfect health. 



Monkey E (into which blood of Situtunga 509-10 was injected). — Arrived 

 Damba, October 8, 1911, having previously been examined regularly at 

 Mpumu with negative results. Examined daily from November 3 to 

 November 17 inclusive, with negative results. On November 5 and 6 

 received blood of Situtunga 509-10, respectively. On November 18 

 trypanosomes first appeared in its blood. 



Monkey F. — Arrived on Damba, November 3, 1911, in perfect health. On 

 November 4 injected with the blood of hippo, Experiment 547 (cp. Table IV). 

 Between November 3 and December 12 examined on 21 occasions, with 

 negative results. At present in excellent health. 



Finally, it may be pointed out that the incubation period in the case of all 

 three positive experiments was in keeping with previous experience. Thus, 



