YAWS. 



179 



be noted before reporting their presence. To stain them in section 

 Levaditi's method is the best. 



T. pertenue. An organism of similar morphology was first 

 reported by Castellani as present in yaws. It is found in smears and 

 sections as with T. pallidum. 



FIG. 58. The spirochaeta refringens is the larger and more darkly stained 

 organism, while the lightly stained and more delicate parasites is the Spirochaeta 

 pallida. (Treponema pallidum). From a chancre stained with Wright's blood 

 stain. (Hirsch by Rosenberger.) 



Trypanosoma. 



The genus Trypanosoma has a more or less spindle-shaped body, 

 along one border of which runs an undulating membrane. There is 

 one flagellum bordering the membrane and projecting like a whip 



