SMALLPOX AND GOWPOX. 



651 



prepared it is much more durable than when dried on 

 ivory points or quills. 



The Appearance of the " Vaccine Organism." Williams 

 has described the appearances observed as follows : 



" The epithelial cells of the skin in the infected areas 

 of vaccinated calves contain characteristic bodies. These 

 bodies are generally spheroidal, but may be quite irreg- 

 ular in outline. They vary in size from that of a 



FIG. 87. 



V V 



Epithelial cells of sebaceous gland of hair containing vaccine bodies. 

 V. Homogeneous vaccine bodies. N. Granular nuclei. X about 600 diam. 



particle of nuclear chromatin to that of the nucleus 

 iteelf, and are sometimes even larger. Usually they 

 are about one-fourth the size of the nucleus. They 

 are seen only in the body of the cell, never in the 

 nucleus, and generally only one is seen in each cell, 

 though there may be three or four. They take most 

 nuclear stains rather more faintly than the nucleus, 

 and are distinguished, moreover, by their homogeneous 



