SMALLPOX, SYPHILIS, CANCER, ETC. 169 



Mitoses in epithelial cells. -In good sections at this 

 stage in a narrow zone separated by a definite interval from 

 the area in which the parasites are visible the epithelial cells 

 are swollen and many of them are in mitosis. The cells 

 occupying the interval between the advanced line of visible 

 parasites and the active epithelial cells probably contain 



FIG. 47. A PORTION OF THE EPITHELIUM OF A RABBIT'S CORNEA FORTY- 

 EIGHT HOURS AFTER VACCINATION. Guarnieri's bodies are seen as 

 roundish dark objects near the nuclei of the epithelial cells. From 

 a photograph of one of the Author's preparations made in 1894. 

 H. and E. x 400. 



parasites in the microhenad stage and the activity of the 

 cells is defensive. 



Variations in the parasites. Though they look quite 

 different the two sets of elements shown in the two parts of 

 Fig. 48 represent the same fact, the passage of the parasites 



