THE FILTERABLE MICROBES 



371 



numerous in the ammon's horn of the brain in cases of street 

 rabies. Preparations should be made from the gray matter of 

 the brain. A bit of this tissue is carefully spread on a slide by 

 exerting moderate pressure upon it with a second slide or a cover- 

 glass and at the same time moving it along the surface of the first 



FIG. 145. Section through the cornu ammonis of brain of a rabid dog; stained by 

 the method of Lentz. Five Negri bodies of different sizes are shown, enclosed within 

 the ganglion cells. The smallest contains only three minute granules. (After Lentz, 

 Centralbl.f. Bakt, 1907, Abt. I, Vol. XLIV, p. 378.) 



slide. The film is fixed in pure methylic alcohol and stained with 

 Giemsa's solution, or it may be stained directly without fixation 

 with Leishman's stain. The Negri bodies are round and some- 

 what irregular in outline from i/i to 27/^1 in diameter, and usually 

 inside the nerve cells. In the interior of the larger bodies, smaller 



