Trypanosoma simiae (T. ignotum) is like T. congolense. It averages 17·5 µ long. It is virulent to monkeys and pigs.
Trypanosoma uniforme, Bruce, 1910.
Fig. 48.—Trypanosoma rotatorium, from blood of a frog. × 1,400. (After Laveran and Mesnil.)
This trypanosome was found in oxen in Uganda.[110] It can be inoculated to oxen, goats and sheep, but is refractory to dogs, rats and guinea-pigs. It has been found in antelopes. It resembles T. vivax, but is smaller (fig. 47), averaging 16 µ in length. A free flagellum is present. It is transmitted by Glossinæ.
Many other trypanosomes occur in mammals, while birds, reptiles, amphibia (fig. 48) and fish also harbour them. The discussion of these forms does not come within the scope of the present work. They are dealt with in Laveran and Mesnil’s “Trypanosomes et Trypanosomiases,” 2nd edit., 1912.
General Note on Development of Trypanosomes in Glossina.
Before concluding the account of trypanosomes, it may be of interest to remark that several African trypanosomes develop in various species of Glossina, and are found in different parts of the alimentary tract and in the proboscis. Thus (a) T. vivax, T. uniforme and T. capræ develop in the fly’s proboscis (labial cavity and hypopharynx) only; (b) T. congolense, T. simiæ and T. pecaudi develop first in the gut of the fly and then pass forward to its proboscis; and (c) T. gambiense and T. rhodesiense develop first in the gut and later invade the salivary glands of the tsetse. The proboscis or the salivary glands in such cases are termed by Duke[111] the anterior station of the trypanosome, wherein it completes its development.