TRYPANOSOMA VIVAX 99 



be spread mechanically by species of Mnsca, Sarcophaga and Comp- 

 somyia, sucking the wounds of infected animals and carrying over the 

 trypanosomes to wounds on healthy ones. 



Endotrypanum schaudinni, Mesnil and Brimont, 1908. 

 This organism was discovered in the blood of a sloth (Choloepus 

 didactylus), in South America (French Guiana). 1 It possesses special 

 interest, in that the best known form of the organism is endoglobular, 

 inhabiting the erythrocytes of the sloth. A free trypanosome in the 

 same animal was considered to be different from the endoglobular 

 form, which was somewhat like a peg-top, and possessed a short 

 flagellum. Darling 2 (November, 1914) has seen the organism in 

 Panama. He describes free crithidial forms in shed blood, but not 

 in the blood-stream of the sloth. 



Trypanosoma boylei, Lafont, 1912. 



This is a parasite of the Reduviid bug, Conorhinus rubrofasciatus. 

 The insect attacks man in Mauritius, Reunion and other places. 

 Lafont infected rats and mice by intraperitoneal injection with the 

 gut-contents of infected bugs. Trypanosomes appeared in the mice. 

 Other flagellate types were assumed by the parasites in the bug. 



MONOMORPHIC TRYPANOSOMES. 



A number of trypanosomes, characterized by relative uniformity 

 in size and structure, may be considered under this heading. They 

 occur in cattle, sheep, goats and horses in Africa, especially West 

 Africa. Morphologically, they are characterized by the posterior 

 (aflagellar) part of the body being swollen, while the anterior part 

 narrows. The nucleus is central and situated at the commencement 

 of the narrowing of the body. The blepharoplast is almost 

 terminal, the undulating membrane is narrow and not markedly 

 folded, so that the flagellar border lies close to or along the body. 

 The flagellum may or may not possess a free portion. 



Some recent workers have considered that 7*. brucei (Zululand 

 strain) and T. evausi are also monomorphic, but they do not exhibit 

 the general characteristics outlined above. T. brucei and T. evansi 

 have already been considered separately. 



The monomorphic trypanosomes, as defined above, include : 



Trypanosoma vivax, Ziemann, 1905. 



This trypanosome 3 occurs in cattle, sheep and goats, and was first 

 found in the Cameroons. It is fatal to cattle. Equities are also 

 affected. Antelopes are the possible reservoirs of the trypanosome. 



1 C. ft. Soc. Biol., Ixv, p. 581. 2 foitrn. Me.i. Research, xxxi, p. 195. 



3 See Bruce and colleagues (1910), Proc. Roy. Soc., B, Ixxxiii, p. 15. 



