PRACTICAL BACTERIOLOGY. 



DEMONSTRATION X. 



Examination of Plate cultures — Gonorrhoeal pus — Pus from 

 Actinomycosis. 



1. Examine the plate cultures from pus, made last 

 day. Make agar and gelatine sub-cultures of any differ- 

 ent varieties of bacteria that may be present. 



Examine the cultures daily, noting characters of 

 growth, so as to aid identity of the species. 



2. Make cover glass preparations from any different 

 varieties of bacteria developing on plates. 



Stain with anilin gentian violet, and also by Gram's 

 method. 



Staining of Gonorrhoeal Pus. 



In the usual manner prepare cover glass films of the 

 pus. It is best to make these directly from the dis- 

 charges. 



3. Stain the dried and fixed films in eosin and 

 methylene blue. 



Note the relationship of the Gonococci to the pus cells. 



4. Stain other films in anilin gentian violet for one 

 minute. Mount these films in water and examine for 

 Gonococci. If present, remove film from slide and wash 

 rapidly several times through alcohol. Then wash in 

 water, dry and mount in the usual manner. The 

 Gonococcus is decolorized. A second film may be 

 treated by Gram's method. The Gonococcus does not 

 retain the stain, when so treated. 



