526 



Description of a Strain of Trypanosoma brucei from Zululand. 

 Part III. — Development in Glossina morsitans. 



By Surgeon-General Sir David Bruce, C.B., F.B.S., A.M.S. ; Major A. E. 

 Hamerton, D.S.O., and Captain D. P. Watson, B.A.M.C. ; and Lady 

 Bruce, B.B.C. (Scientific Commission of the Boyal Society, Nyasaland, 

 1912-14.) 



(Keceived March 17— Eead March 26, 1914.) 

 [Plate 25.] 



Introduction. 



In previous papers* the morphology of this trypanosome and its action on 

 animals were described. The chief object of this paper is to compare the 

 development of this species of trypanosome with that of the trypanosome 

 causing disease in man in Nyasaland — the T. rhodesiense of Stephens 

 and Eantham. The development of the latter has already been described.f 

 It will therefore only be necessary here to present the various data in the 

 form of tables and figures, which can then be compared with similar tables 

 and figures in the previous paper. 



The Development of T. brucei, Zululand Strain, 1913, in G-. morsitans. 



.Seven experiments were made with laboratory-bred flies. Three of these 

 were positive and four negative. Two experiments were also made with 

 wild flies, both of which were positive. 



Table I. — Laboratory-bred Flies. 



Date. 



Expt. 



No. of 

 flies 

 used. 



Experiment 

 positive or 

 negative. 



No. of infected 

 flies found. 



No. of days 

 before flies 

 became infective. 



Temperature 

 at which flies 

 kept. 



1913. 















Feb. 11 



1857 



58 





1 







„ iv 



1909 



50 



+ 



10 



21 



? 



Mar. 11 



1988 



45 



+ 



20 



13 



84° P. (29° C.) 



„ 17 



1996 



55 





4 





April 25 



2111 



50 





3 







May 26 



2188 



30 





1 







June 23 



2188a 



20 



+ 



8 



14 



84° E. (29° C.) 



* 'Eoy. Soc. Proc.,' this vol., pp. 493 and 511. 

 t Ibid., this vol., p. 516. 



