232 GONORRHCEA. 



immersed for a minute in a solution of methyl-blue, composed of 1 

 part of methyl-blue, 33 parts of alcohol, and 66 parts of water, 

 after which it is washed in water, and after drying mounted in 

 Canada balsam. 



Schuetz (Munch, med. Wochensehrift, No. 14. 1889) recommends 

 the following method : The carefully prepared cover-glass prepara- 

 tions are immersed for from five to ten minutes in a cold, filtered, 

 and saturated solution of methylene-blue in five per cent, carbolic 

 acid water. They are then washed in distilled water, and after- 

 ward placed for a moment in a solution of five drops of acetic acid 

 in twenty cubic cm. of distilled water, and again washed in pure 

 water. Everything in the specimen is now decolorized, except 

 the gonococci, which remain distinctly blue. Double staining 

 with safranin can now be done when the gonococci and epithelial 

 cells show a blue color, while the pus cells and their nuclei are 

 found salmon-colored. 



CULTIVATION. The cultivation of the gonococcus. is associated 

 with many difficulties. Bumm (Der Microorganismus der Gonor- 

 rhceischen Schleimhaut-Erkmnkung, Gronococcus Neisser, Wiesbaden, 

 1887), succeeded best in obtaining a pure culture upon blood serum 

 of the calf and sheep, especially if to the coagulated serum a little 

 serum from human blood is added, and after coagulating again the 

 nutrient medium is kept at an even temperature of 30 to 34 C. 

 (86 to 93.2 F.). If the temperature exceeds 38 C. (100.4 F.), 

 the gonococci are invariably destroyed. By using the above nutrient 

 substance Bumm observed, eighteen to twenty-four hours after in- 

 oculation, the whole surface covered with the growth. The culture 

 grows only upon the surface and does not liquefy the soil. The 

 addition of very mild antiseptics to the soil completely prevented 

 the growth of the microbe. Cultivations on agar-agar and gelatin 

 never proved successful. 



Kreis (" Beitrage zur Kenntniss der Gonococcen," Wiener med. 

 Woehenschrifi, 1885, Nos. 30-32) succeeded in cultivating the gono- 

 coccus upon agar-agar with an admixture of Kemmerich's meat- 

 peptone, kept at a temperature of 30 to 40 C. (86 to 104 F.). 

 The culture soil was not liquefied and the size of the cocci was uni- 

 form; addition to the soil of 2 per cent, alkali arrested further 

 growth of the culture. 



Krause ("Die Micrococcen der Blenorrhcea neonat.," Centralblatt 

 /. d. prakt. Augenheilk., 1882, p. 134) made cultivation experiments 

 upon meat-iufusion-peptone-gelatin, but failed in many instances. 

 After many trials with serum of animal blood he finally succeeded 

 in obtaining a culture by placing the glass tubes in an incubator, 

 in which the temperature was kept from 30 to 38 C. (86 to 

 100.4 F.). The culture appeared on the surface, starting from 



