188 Drs. Stephens and Blacklock. T. brucei, Plimmer and [Dec. 7, 



double the width, and is more irregular in shape. The protoplasm is quite 

 homogeneous and much more delicate, and it stains very faintly with the 

 methylene blue." They are still to be found in films, and we easily found 

 them in Dr. Plimmer's old films, but we found only extremely rarely forms 

 that could be called " stumpy." We think that if they had been present 

 these observers would hardly have failed to have noticed and drawn attention 

 to them, as they have a striking appearance. 



(4) Bruce and others (5) make a comparison between T. brucei, Uganda, 

 1909, and T. brucei, Zululand, 1894. 



They state that many of the old Zululand preparations are still extant, so 

 that it has been possible to do this. The preparations were, however, 

 15 years old, and had been stained with carbol fuchsin. The slides were got 

 from horse, donkey, ox, monkey, dog ; 200 trypanosomes were measured 

 from the Zululand strain and 172 from the Uganda strain. The curves 

 obtained in this way certainly resemble one another, though in one case the 

 peak is at 18 fi, in the other case at 20 /a. 



Also trypanosomes are figured from each strain, and there can be little 

 doubt that there is a close resemblance, if not identity, viz., in the fact that 

 both possess both long and stumpy forms. " With the evidence available 

 the Commission consider themselves justified in considering the trypanosome 

 recovered from the Uganda ox to be identical with T. brucei, the cause of 

 Nagana in Zululand and other parts of South Africa." 



Further, Bruce states in another paper (6) that T. brucei (Uganda strain) 

 has actually 26 per cent, of non-flagellated forms. 



(5) In 1911 La veran (7) published an article, entitled "Identification et 

 essai de classification des trypanosomes des mammiferes." 



In this article he places T. brucei in his Group I, " Trypanosomes chez 

 lesquels le flagelle presente toujours une partie libre," whereas he places 

 T. gambiense in his Group III, " Trypanosomes ayant des formes a flagelle 

 libre et des formes sans flagelle libre." 



Or, in other words, T. brucei is classed among the monomorphic trypano- 

 somes while T. gambiense is among the dimorphic. We have then two 

 opposite statements as to the morphology of T. brucei, (1) that it is mono- 

 morphic and (2) that it is dimorphic. 



We possess two strains of (so-called) T. brucei in the laboratory, viz., the 

 Zululand strain, of which we have given the origin above, and the Uganda 

 strain from Surgeon-General Bruce, obtained originally from the ox in 

 Uganda in 1909. These strains have been maintained continuously at 

 Runcorn in a variety of animals, the Zululand strain for 4J years, and the 

 Uganda strain for 2\ years. In the case of the Uganda strain it was lost in 



