TOO 



THE ANIMAL PARASITES OF MAN 



It is probably transmitted by Glossina palpal is and other tsetse flies. 

 Its movement is very active. It possesses a free flagellum (fig. 45) and 

 it averages 23/4 to 24 //, in length. T. cazalboui (Laveran, 1906) the 

 causal agent of "souma" in bovines and equines in the French Sudan 

 is probably synonymous with 7\ vivax. 



Trypanosoma caprae (Kleine, 1910) is allied, 



but is somewhat broader and more massive. 



It was found in goats in Tanganyika. 



Trypanosoma congolense, Broclen, 1904. 



Probable synonyms. Trypanosoma dimorphon, Laveran 

 and Mesnil, 1904 ; Trypanosoma nanum, Laveran, 

 1905 ; Trypanosoma pecorum, Bruce, 1910 ; Try- 

 panosoma confusum, Montgomery, 1909. 



This trypanosome causes disease among 

 horses (e.g., Gambia horse sickness), cattle, 

 sheep, goats, pigs, and dogs. It is widely dis- 

 tributed in Central Africa (e.g., Gambia, Congo, 

 Uganda, Nyasaland), the strain probably being 

 maintained naturally in big game. It is trans- 

 mitted by various Glossince, and perhaps by Tab anus and Stomoxys. It 

 is said to develop in the gut and proboscis of Glossina palpalis and 

 G. morsitans. The trypanosome averages 13 /x to 14 //. in length and 

 has no free flagellum (fig. 46). It is about 2 //, broad. Formerly 

 T. nannm and T. pecorum were said to differ in their pathogenicity, the 

 former being said not to infect the smaller laboratory animals. Yorke 

 and Blacklock (1913), however, consider 

 that the virulence varies and that these 

 trypanosomes are probably the same. 



F IG . 45 . Trypanosoma 

 vivax. X2,oco. (Original. 

 From preparation by Fan- 

 tham.) 



FlG. 46. Trypanosoma 

 congolense. x 2,000. (Orig- 

 inal. From preparation by 

 Fantham.) 



FlG. 47. Trypanosoma 

 uni forme, x 2,000. (Orig- 

 inal. From preparation by 

 Fantham.) 



The T. dinwrphon originally obtained by Button and Todd (1903) 

 in Gambian horse sickness has been shown to be a mixture of T. vivax 

 and T. congolense. 



Trypanosoma simiae (T. ignotum] is like T. congolense. It averages 

 17-5 fju long. It is virulent to monkeys and pigs. 



