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GENERAL MICROBIOLOGY 



EXERCISE 29. ANJESZKY'S METHOD OF STAINING 



SPORES 



Spores are not stained by the ordinary staining methods, 

 as their physical nature differs from that of the vegetative 

 rods within which they are formed. By proper treatment 

 with strong anilin dyes, however, it is possible to force the 

 stain into the spore. Once within the spore it is as dif- 

 ficult to remove the dye as it was to cause it to enter. 



FIG. 33. Contrast Spore Stain, Carbol-fuchsin and Methylen Blue, 

 X1500. (Orig. Northrup.) 



By a careful decolorization with a weak acid, it is pos- 

 sible to remove the stain from everything on the cover- 

 glass except from the spores. Then, on application of a 

 dye of a contrasting color, the specimen will show, e.g., a 

 bright red spore within a blue bacterium. 



The fundamental principles of this method are also 

 used for staining " acid-fast " organisms, ^ Bad. tuber- 

 culosis. 



Apparatus. Clean cover-glasses; clean slides; cover- 

 glass forceps; platinum loop and needle; Bunsen burner; 



