100 



ESSENTIALS OF BACTERIOLOGY. 



possible that the bacillary parasitic form is only one stage in 

 the life history of the organism. 



Little granules arranged like streptococci, which take the 

 characteristic stain, and look as if the protoplasm had been 

 destroyed that enclosed them, are frequently found in sputum. 



FIG. 53. 



Klatsch preparation. 



Bovine tubercle-bacilli are about one-third smaller than human 

 tubercle bacilli. 



Staining. The tubercle bacilli require special methods to 

 stain them, and a great number have been introduced. They 

 are stained with great difficulty : but once stained, they are 

 very resistant to decolorizing agents. Upon these facts all the 

 methods are founded. 



