TRYPANOSOMA BRUCEI 541 



Sudan, Uganda, Rhodesia, East Africa, the territory around Lakes Nyasa 

 and Tanganyika, and all the districts bordering on the Transvaal except 

 those to the south. It will be seen that in West Africa this trypanosome 

 is apparently absent, but a form morphologically indistinguishable from 

 it was described from Togoland and the surrounding districts by Mesnil 

 and Brimont (1909), and was named by them T. togolense. It was dis- 

 tinguished from T. brucei by immunity and inoculation tests. A trypano- 

 some of much wider distribution in West Africa is T. pecaudi Laveran, 

 1907, which produces a disease known as baleri. Laveran and Mesnil 

 describe this trypanosome as differing in certain respects from T. brucei, 

 especially as regards the presence of certain small forms. The trypano- 

 some which was described by Balfour (1909) and the writer (1909) in the 

 Sudan as T. pecaudi is indistinguishable morphologically from T. brucei. 

 Macfie (1913) described a trypanosome from Northern Nigeria which was 

 indistinguishable from T. brucei, and the same form was isolated by Macfie 

 (1914) by feeding wild G. tachinoides on guinea-pigs, so that it would appear 

 that a trypanosome of the polymorphic type exists in animals all over 

 tropical Africa. According to Laveran and Mesnil, T. pecaudi and T. togo- 

 lense can be distinguished from T. brucei by their immunity reactions and 

 other features. It is extremely doubtful, however, if any real specific 

 differences exist between these forms. Similarly, the trypanosome which 

 was isolated from a bush buck in the Luangwa Valley by Kinghorn and 

 Yorke (1912c), and named by them T. multiforme on account of certain 

 short forms of the T. congolense type, which were mixed with others of 

 the T. brucei type, may in reality be T. brucei, or possibly a mixed infection 

 of T. brucei and T. congolense. T. suis, described by Ochmann (1905) 

 and Geisler (1912) from pigs in Somaliland, is probably T. brucei, as 

 also T. elephantis, discovered by Bruce et al. (19096) in an elephant of 

 Uganda. Bruce et al. (1914^) discovered a trypanosome in three dogs 

 in Nyasaland, which they regarded as an aberrant form of T. brucei. 

 It produced a chronic type of infection instead of the usual acute one, 

 and differed slightly in other respects from the usual T. brucei strains. 

 It was inoculable to rabbits, dogs, and white rats, but not to oxen, goats, 

 monkeys, or guinea-pigs. Though it was considered to be a modified 

 form of T. brucei, the name T. anceps was suggested in case it should be 

 decided to regard it as a new species. 



Duke (1913) isolated a trypanosome of the T. brucei type from donkeys 

 in East Africa. It was readily inoculable to most laboratory animals, 

 but of seven guinea-pigs inoculated, only one became infected. The 

 trypanosome was shown to develop in G. 2J(ilp(ilis with salivary gland 

 infection. Knuth and Du Toit (1921), for reasons which are not quite 

 clear, propose to name this trypanosome T. dukei. There seems to be no 



