causing Disease in Man in Nyasalaad. 



33 



Table IV agrees very closely with the same table given in the paper on 

 the " Morphology of the Trypanosome causing Disease in Man in Nyasaland."* 

 It is doubtful if this detailed method of measurement assists in putting 

 trypanosomes in their proper places, but it may be that when more work has 

 been done, something may emerge. There can be little doubt that 

 morphology, in future, will play an important part — perhaps the most 

 important part — in the classification of trypanosomes. 



Breadth. — The average breadth is 3 - 45 microns (maximum 5 '75, minimum 

 1*5). The short and stumpy average 3*7 (maximum 575, minimum 2), the 

 intermediate 3*16 (maximum 5, minimum l - 5), and the long and slender 2'84 

 (maximum 4*25, minimum T75). The breadth of the widest part of the body 

 of the 1000 trypanosomes is measured, including the undulating membrane. 



Shape. — This trypanosome closely resembles in general appearance the 

 various strains which have already been described from man, wild game and 

 wild G. raorsitans. Three black-and-white plates are given (Plates 1-3), which 

 will give a better idea of the appearance of this strain than a written 

 description. 



Table V. — Percentage of Posterior-Xuclear Forms found among the Short and 

 Stumpy Varieties of the Trypanosome of the Mzimba Strain. 



Date. 



Experiment 

 No. 



Animal. 



Percentage among short 

 and stumpy forms. 



Proportion to all forms 

 per 1000. 



1912. 











liar. 27 ... 



367 



Dog 











• „ 28... 



367 



3) 



10 



60 



„ 28... 



366 



53 



3 



18 



„ 29... 



367 





8 



48 



„ 29... 



366 



" 



13 



78 



„ 30 ... 



366 



55 



12 



72 



Apr. 1 ... 



366 





7 



42 



„ 25 ... 



387 





15 



90 



„ 29... 



387 





25 



150 



May 2 ... 



387 





37 



222 



„ 10... 



513 



Eat 



11 



66 



„ 10 ... 



512 



:> 



22 



132 



„ 11... 



513 



J) 



19 



114 



„ 11 ... 



512 



it 



12 



72 



„ 13... 



513 



5) 



7 



42 



„ 13... 



512 





5 



30 



„ 14... 



513 





10 



60 



„ 15... 



513 



5) 



28 



168 



• „ 16 ... 



513 



J* 



33 



198 



„ 16... 



512 



3) 



3 



18 





14 -7 



'88 



* 'Roy. Soc. Proc.,' 1912, B, vol. 85, p. 428. 



VOL. LXXXVII. — B. 



