Isolation and Cultivation 395 



The gonococci are small, the length of one of the coffee-bean cocci 

 being about 1.6 ju, its breadth about 0.8 /JL. They are not motile, 

 nor provided with flagella, and are without spores. 



Quite as characteristic as the form of the organism is its rela- 

 tion to the cells. In most of the inflammatory exudates the gono- 

 cocci are contained either in epithelial cells or in leukocytes, very 

 few of them lying free. This intracellular position is supposed to 

 depend upon active phagocytosis of the cocci by the cells. It may 

 not obtain in old lesions. 



Staining. They stain readily with all the aqueous solutions of 

 the anilin dyes best with rather weak solutions, but not by Gram's 

 method. 



Fig. 143. Gonococci in urethral pus. 



The organisms contained in pus can be beautifully shown by 

 first treating the prepared film with alcoholic eosin, and then with 

 Loffler's alkaline methylene blue. A differential color test can be 

 made by staining the film by Gram's method and then with aqueous 

 Bismarck brown, or, what may be still better, with 3 per cent, 

 aqueous solution of pyronin. Ordinary pus cocci, taking the 

 Gram's stain, appear blue-black; the gonococci, taking the counter- 

 stain, are brown in the former, purplish red in the latter case. 



Isolation and Cultivation. The organism does not grow upon 

 any of the ordinary culture-media, and grows very scantily upon 

 any artificial medium. Wertheim* succeeded in cultivating it by- 

 diluting a drop of gonorrheal pus with human blood-serum, mixing 

 this with an equal part of melted 2 per cent, agar-agar at 4oC., 

 and pouring the mixture into Petri dishes, which, as soon as the 

 medium became firm, were stood in the incubator at 37C. or, 

 preferably, 4oC. In twenty-four hours the colonies could be 

 observed. Those upon the surface showed a dark center, sur- 

 rounded by a delicate granular zone. 



* "Archiv. fur Gynakologie," 1892. 



