72 BACTERIOLOGY 



B. Doubtfully chromogenic; growth on gelatin or agar light yellow - 



yellowish white. 



1. Gelatin liquefied. Class V, p. 91. 



2. Gelatin not liquefied. Class VI, p. 94. 



3. Do not grow on gelatin. No. 61. 



C. Distinctly chromogenic ; form a pigment on gelatin or agar. 



1. Pigment yellowish orange. 



a. Gelatin liquefied. Class VII, p. 96. 



b. Gelatin not liquefied. Class VIII, p. 102. 



2. Pigment reddish, pinkish, flesh-colored. Class IX, p. 105. 



3. Pigment bluish black. Class X, p. 108. 



CLASS I. WITHOUT PIGMENT ON GELATIN OR AGAR. DO NOT 

 GROW ON ORDINARY CULTURE MEDIA, OR, AT BEST, BUT 

 VERY POORLY. 



I. No growth on ordinary culture media. 



1 . M. gonorrhcece (Bumm) Flugge. 



II. Very feeble growth on gelatin or agar. 



2. M. catarrhalis Frosch-KoUe. 



I. M, gonorrhoeae (Bumm) Flugge 



Gonococcus Neisser: Centralblatt f. Med. Wissensch., 1879, No. 28. 



Diplococcus gonorrhoscB Bumm : Der Mikroorganismen der gonorrh. Schleimhauterkrank- 



ung, Wiesbaden, 1885. 

 Micrococcus gonorrhcecB Flugge : Die Mikroorganismen, 1886. 



Morphology. Coccio .8-1 .0 : 0.6-0.8 /«, ; in pairs, flattened at points of contact, 

 or in tetrads. Decolorized by Gram's method. Grow only in specially 

 prepared media, best in serum agar, one part of human ascites fluid and 

 two parts of melted agar. 



Differential diagnosis. Examination of pus, cover-glass preparations, shows 

 gonococci within the cells, when stained with alkaline methyl blue ; or 

 stain by Gram's method, and then with aqueous solution of Bismarck 

 brown. 



Pathogenesis. Not pathogenic for smaller laboratory animals. Inoculation 

 experiments upon man give positive results. 



Habitat. In gonorrheal pus, and associated with lesions of subsequent in- 

 fection. 



