524 BACTERIOLOGY. 
fuchsin; not so readily with methylene-blue, which is, 
however, one of the best staining agents for demon- 
strating its presence in pus. Beautiful double-stained 
preparations may be made from gonorrheal pus by 
treating cover-glass smears with methyl-violet and 
eosin. Gonococci are decolorized by Gram’s solution; 
but this cannot be depended upon alone to absolutely 
distinguish the gonococcus from all other diplococci 
- Fic. 69. 
Gonococcus in pus-cells. >< 1100 diameters. 
found in the urethra and vulvo-vaginal tract, for espe- 
cially in the female other diplococci are occasionally 
found which are also not stained by Gram’s method. 
‘It serves, however, to distinguish this micrococcus from 
the common pyogenic cocci, which retain their color 
when treated in the same way, and in the male urethra 
it is practically certain, as no organism has been found 
in that location which in morphology and staining is 
identical with the gonococcus. It is certainly the most 
distinctive characteristic of the staining properties of 
