GONOOOCOUS 203 



To differentiate them from other diplococei, Stein- 

 schneider and Galewski recommend that the preparations 

 should be left for half an hour in a solution of gentian violet 

 in aniline water, rinsed, laid for five minutes in solution of 

 potassium iodide, and left in alcohol until decolorised, after 

 which they are again rinsed, dried, and double-stained 

 in dilute alkaline solution of methyl blue. The gonococci 

 are pale, the other diplococei stained blackish. 



In making a rapid examination of a series of secre- 

 tions for the presence of gonococci, F. Winkler uses the 

 following drying-on process : — A clean slide is prepared with 

 a small drop of gonorrhoeal secretion, and immediately 

 passed several times through the flame without being 

 previously dried in air. The pus is thus desiccated in a thin 

 film, over which a concentrated alkaline solution of methyl 

 blue is next poured ; after a half a minute the preparation 

 is washed in water, dried over the flame, and mounted in 

 Canada balsam. The pus-cells appear pale blue, the 

 gonococci dark blue. 



The ordinary nutrient materials which prove favourable 

 to the growth of other micro-organisms fail us completely 

 in the case of gonococcus, which grows neither on gelatine, 

 agar, nor potato, though on the other hand, as Bumm has 

 proved, it thrives on human blood-serum. According to him 

 the cultures exhibit a greyish -yellow layer, resembling from 

 its pointed prominences a group of mountains, and whose 

 margins extend diffusely into the surrounding parts. The 

 serum is not liquefied. The most suitable temperature lies 

 between 33° and 27° C. Growth is very slow, and comes to 

 an end in three days. Cultivation experiments on plover's 

 egg albumen gave good results in the hands of Von Schrotter 

 andF. Winkler, a thin, tolerably transparent, whitish deposit 

 showing itself on the surface of the solidified mass of white 

 of egg in as short a time as six hours at incubation tem- 



