XVIIl] TRYPANOSOMA SIMI^ 353 



tube was filled with small trypanosomes of the congolense type 

 without any free flagellum, whilst the parasites that swarmed 

 in the labrum were of the Leptomonas type. 



REFERENCES. 

 Broden, A. (1904). Bull. Soc. d'litudes Coloniales, Bnixelles, February, 



1904. 

 Laveran and Mesnil (191 2). Trypanosomes et Trypanosomiases. 

 Montgomery and Kinghorn (1909). Ann. Trop. Med. and Parasit. 



vol. III. p. 349. 

 Rodhain, van den Branden, Pons and Bequaert (1912). Bull. Soc. 



Path. Exot. vol. V. p. 281. 

 Roubaud (1909). Thdse de doct. es sci. nat. Paris, pp. 153 and 161. 



Trypanosoma simiae Bruce, Harvey, Hamerton, Davey and 

 Lady Bruce, 19 12. 



Synonym. T. ignotum Kinghorn and Yorke, 1912, 



General account. This species of trypanosome has been 

 recorded from Nyasaland, Central Angoniland, and North- 

 Eastern Rhodesia, where a large percentage of Glossina mor- 

 sitans are naturally infected with the parasite. Its pathogenic 

 properties are very remarkable, since it only affects such widely 

 different animals as monkeys and goats. Oxen, baboons, dogs, 

 guinea-pigs, and white rats, seem to be immune. 



In goats T. simian sets up a chronic disease, but in monkeys 

 the infection is rapidly fatal, for in a series of 19 the average 

 duration of life after the trypanosomes were first seen in the 

 blood was only 2-9 days. 



Morphology. When living the parasite shews active pro- 

 gressive movements, some individuals passing completely 

 across the field of the microscope. The dimensions of the 

 trypanosomes as found in the monkey and the goat, are 

 found to vary from 14 to 24 microns in length, by i to 2-75 

 microns in breadth, the mean being 18 microns in length by 

 1-75 in breadth. The parasites are monomorphic and, as a 

 rule, fairly uniform in shape. The authors give the following 

 summary of its characters : 



" Elongated, narrow, undulating body ; posterior extremity 

 bluntly pointed or rounded ; anterior extremity pointed ; 



H. B. F. 23 



