CHAPTER XXIV. 

 EXAMINATION OF BUCCAL AND PHARYNGEAL MATERIAL. 



IN a preparation made from material taken by a sterile swab from 

 the region of the normal buccal and pharyngeal cavities and stained by 

 Gram's method, we are struck by the variety of organisms present. 



Gram positive and Gram negative staphylococci are present, as are 

 also streptococci, pneumococci, leptothrix forms and very probably 

 yeasts and sarcinae types with many Gram negative bacilli. If 

 pseudodiphtheria organisms are present, we have these showing a 



FIG. 80. Vincent's angina. Spirochaeta vincenti. (Coplin.) 



Gram positive reaction. If this material is smeared on agar plates 

 and cultured at 37 C., we are struck by the fact that the colonies on the 

 plates may be exclusively staphylococcal and streptococcal. 



It is very difficult, if not impossible, to distinguish a pneumo- 

 coccus colony from a streptococcus one on a plate culture. The presence 

 or absence, however, of the pneumococcus is distinctly shown in the 



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