560 



Dr. H. L. Duke. Some Observations on [Aug. 16, 



the peripheral blood as regards ordinary routine examination, while the 

 animal shows no symptoms whatever. 



When, however, this trypanosome occurs together with T. vivax, or 

 possibly with T. gamhiense, the animal may become rapidly emaciated, and 

 die with paretic symptoms, particularly in the hind limbs. This, however, is 

 not a constant phenomenon, as is shown in the case of Goat 512, which was 

 infected in November, 1911, simultaneously with T. uni forme, vivax, and 

 gamhiense, and at the time of writing is apparently in perfect health. 



The following table is of interest, as affording marked contrast to the 

 course of disease described by Bruce : — 



Expt. 



Infected. 



Duration of disease. 



Bemarks. 



Qoat 352 



„ 397 



„ 431 



Calf 481 



„ 536 



„ 573 



„ 616 



Bushbuck 620 

 Sheep 534 



Nov., 1910 



Jan., 1911 

 Feb., „ 

 Jan., „ 



Feb., „ 



Mar., „ 



Killed Dec, 1911 



Died" in July, 1912, 

 after 18 months 



Up till date of infection 

 with T. gamhiense 

 showed good health 



In apparently perfect health at 

 time of death. 



No trypanosomes visible during last 

 week. Slight emaciation. 



Killed by leopard. Apparently in 

 excellent health when attacked. 



Alive and well July, 1912. 



In excellent health July, 1912. 

 Infected with T. qambiense in 

 Feb., 1912. Died May, 1912. 



In all the above experiments, the strain employed was derived originally 

 from a wild bushbuck shot at the Lake shore. 



The strain employed by Bruce and his collaborators was derived originally 

 from oxen, which may explain the difference in the virulence. 



Antelope as a Reservoir of T. uniforme. 



Two situtunga which were brought alive to the laboratory were found to 

 harbour this trypanosome as a natural infection. 



These animals have been kept under observation, and from time to time 

 laboratory-bred G. palpalis have been fed upon them. These experiments 

 are summarised in the following table : — 



