262 GONORRHCEA AND SOFT SORE 



undergo degeneration, becoming swollen and of various sizes, 

 and staining very irregularly. Degenerated forms are seen even 

 on the second day, whilst in a culture four or five days old com- 

 paratively few normal cocci may be found. The less suitable 

 the medium the more rapidly does degeneration take place. 

 When mixed with other organisms the gonococcus may be 

 separated by serum-agar plates (p. 43). 



On ordinary agar and on glycerin-agar some growth may 

 take place when the reaction is just alkaline to litmus, but these 

 media are quite unsuitable for ordinary purposes. The organism 

 does not grow on gelatin, potato, etc. 



Comparison with Meningococcus. The morphological and 

 cultural characters of the gonococcus and meningococcus are in 

 many respects closely similar ; the following points are of 

 importance in distinguishing them. The conditions of growth 

 of the gonococcus are more restricted than those of the meningo- 

 coccus. The gonococcus usually does not grow on the ordinary 

 agar media, whereas the meningococcus grows well, at least after 

 the first sub-culture. The colonies of the latter are more opaque 

 and have more regular margins than those of the gonococcus. 

 The meningococcus grows well in bouillon, producing a general 

 turbidity, whereas the gonococcus does not grow ; even in serum 

 bouillon the latter organism flourishes feebly, and the scanty 

 growth falls to the bottom leaving the medium clear, whilst the 

 meningococcus produces'^abundant growth with general turbidity. 

 The fermentative effects have also been studied, and the chief 

 results obtained are that glucose is the only sugar usually 

 employed which is fermented by the gonococcus, whereas the 

 meningococcus always ferments maltose also. (For fermentative 

 tests in the case of the gonococcus, solid media, as introduced 

 by v. Lingelsheim, should be used, the serum medium of Martin, 

 with litmus and the particular sugar added, being specially 

 suitable.) 



Specific serum reactions agglutination, opsonic action, 

 bactericidal action, and fixation of complement have been 

 studied by Torrey, Elser and Huntoon, and Martin, in the case 

 of the two organisms. The general results obtained are that 

 each organism represents a somewhat heterogeneous group 

 showing considerable variations as regards the tests mentioned. 

 An anti-gonococcus serum produced by injecting one strain of 

 gonococcus has the maximum effect on that strain, whilst its 

 action on other strains may be much feebler ; so also with an 

 anti-meningococcus serum in relation to different strains of 

 meningococci. An anti-gonococcus serum may have some effect, 



