218 Trypanosome causing Disease in Man in Nyasaland . 



From an examination of these Tables it will be admitted, in spite of the 

 paucity of the material, that the Naturally Infected Dog strain belongs to the 

 same group as T. gambiense and T. brucei vel rhodesiense in regard to its mode 

 of development in G. morsitans. 



The Type of Trypanosome found in the Infected Flies. 



A number of drawings of the developmental forms of the Naturally 

 Infected Dog strain of trypanosome was made from the alimentary tract and 

 salivary glands of the infected tsetse flies. In the intestine the same type 

 of trypanosome was found which has already been described and figured in 

 previous papers.* In the only infected fly which showed a development in 

 the salivary glands, the trypanosomes were described in the living unstained 

 preparations as being exceedingly numerous, small and active. In the 

 stained preparations the trypanosomes were seen to be typical " blood 

 forms " and absolutely identical to those figured in the development of the 

 trypanosome causing disease in man in Nyasalandf and also in that of 

 T. brucei, Zululand, 1913.J It is therefore unnecessary to figure them again. 



Conclusion. 



The trypanosome of the Naturally Infected Dog strain belongs to the same 

 group as T. gambiense and T. brucei vel rhodesiense, the trypanosome causing 

 disease in man in Nyasaland, and is probably merely a weak strain of the 

 latter species. 



* 'Roy. Soc. Proc.,' B, vol. 83 (1911). 

 t Ibid., B, vol. 87, p. 516. 

 + Ibid., B, vol. 87, p. 493. 



