PLATE I 



FIG. 1. 

 f\i 



ni 



V 



Cover-glass preparation of perieardial exudate, showing 

 bacillus pyoeyaneus stained "blue, and the bacillus tuber- 

 culosis stained red. (Ernst'.) 



FIG. 2. 



*. 



s - 



':." 





Urethral dischnrge from a case of gonorrhoea, showing 

 gonococei enclosed in pus corpuscles, and lying free in the 

 discharge. Stained with methylene blue. (C. E. Simon.) 



