causing Disease in Man in Nyasaland. 



201 



It is evident that in this case there is little difference in type in the 

 trypanosomes taken during the first nine days and the last nine days of an 

 infection. In the former there are 25 per cent, short and stumpy forms, 

 37 per cent, intermediate, and 38 per cent, long and slender ; in the latter 

 22, 43, and 35 per cent, respectively. 



Tahle XX.— Percentage of Posterior-nuclear Forms found among the Short 

 and Stumpy Varieties of the Trypanosome of Strain X, Dongolosi. 



Date. 



Experiment 

 No. 



1913. 





Nov. 27 



2437 



„ 28 



2437 



Dec. 2 



2437 



„ 3 



2437 



„ 4 



2437 



,, 5 



2437 



„ 6 



2437 



„ 7 



2437 



„ 8 



2437 



,. 9 



2437 



Animal. 



Eat 



Percentage among short 

 and stumpy forms. 



Average 



1 

 3 

 

 1 

 10 

 3 

 4 

 7 

 10 

 11 



5 -0 



Breadth. — The following Table gives the breadth of the trypanosome of 

 Strain X, Dongolosi. 



Table XXI. — Measurements of the Breadth of the Trypanosome of Strain X, 



Dongolosi. 



Date. 



Experiment 

 No. 



Animal. 



Number of 

 trypanosomes 

 measured. 



In microns. 



Average 

 breadth. 



Maximum 

 breadth. 



Minimum 

 breadth. 



1913 



2437 



Eat 



500 



2-71 



4-50 



1 -25 



To Ascertain the Type of Trypanosome which arises from a Single 



Trypanosome. 



There is always, when dealing with a dimorphic type of trypanosome, a 

 danger of there being two species present. Some experiments were, therefore, 

 made by inoculating animals with a single trypanosome, to find out if the 

 original dimorphic type would appear. The single trypanosomes were picked 

 out in the usual way, by means of dilution and capillary tubes. The blood of 



