THE BLOOD. 237 



of the diameter of a red blood corpuscle. The convex border of 

 the body contains a delicate membrane which extends to the end 

 of the body, forming a tail. The body of the parasite contains 

 ■bright round granules which do not take the stain. Very destruc- 

 tive in South America. 



Fig. 5' 



Nagana, Tsetse Disease, Surra. Occurs in cattle, solidungula, 

 ■camels, dogs and cats. This is a pernicious anemia caused by 

 Trypanosoma Evansi (introduced into the tissues through the me- 

 dium of the tsetse fly). Fever, muscular weakness, edema, affec- 

 tion of the eyes, pronounced anemia. A flaggellate parasite, like 

 the above, 20 to 40 mic,ra long, 1 to 2.5 micra in diameter, actively 

 motile. 



