278 RABIES. . 



ammonis (Hippocampus major). They may be demonstrated by 

 staining smears of brain substance by some Romanowsky method, 

 especially by the Giemsa stain. As their relation to the nerve-cell is 

 more or less disturbed by such a method, it is preferable to fix brain 

 tissue about the region of the cornu ammonis in Zenker's fluid, then to 

 imbed in paraffin and make sections. These are stained with Giemsa 's 

 stain and the Negri bodies are brought out as lilac-red bodies in the 

 blue cytoplasm of the nerve-cells. It is necessary to differentiate in 

 95% alcohol. In addition to examining for the Negri bodies, a rabbit 

 may be inoculated subdurally with a sterile salt-solution emulsion of 

 the medulla of the dead dog. 



If the brain or cord of the dog are to be sent to a laboratory for 

 examination they should be packed in ice or placed in glycerin. Take 

 of glycerin one part and one part water. Sterilize the diluted glycerin 

 by boiling, allow to cool, and drop the pieces of brain tissue into this. 

 This does not kill the virus. It is supposed by some that Negri bodies 

 are protozoal in nature notwithstanding the fact that the virus will pass 

 through a coarse Berkefeld filter. 



Antirabic serum has been prepared by injecting sheep with emul- 

 sions of rabid rabbits' cord and brain at first intravenously, then 

 subcutaneously. 



