138 BACTERIA 



Morphology and Stains. The morphology of this organism is 

 peculiar and characteristic. Always found in pairs which are ce- 

 mented by an invisible substance. These pairs resemble coffee 

 beans with the concave sides opposite each other and slightly apart; 

 or kidneys placed with the hilums facing each other. 



In pus it is generally found within the pro- 

 toplasm of the leucocytes, about, though never 

 within, the nuclei. It is non-motile; has no 

 flagella, or spores, and stains readily with all 

 the basic stains, but best with Loffler's blue. 

 It is decolorized by Gram's stain. This point 

 is most important in differentiating it from 

 FIG. 43. Gonococci other diplococci, except the meningococcus. A 

 ' diplococcus is said to exist normally in some 



urethras that resembles the gonococcus, but 

 is Gram positive. 



Oxygen Requirements. It is a facultative anaerobe. 

 Vital Conditions. It is cultivated with difficulty in culture 

 media. Grows best at about 36 C. As it dies quickly in usual 

 culture media, a special one must be employed; that containing as- 

 citic or hydrocele fluid, blood or urine is best. It does not withstand 

 high temperature, drying, or light, very long, and is very easily killed 

 in culture by silver salts. In tissues of the urethra it may live many 

 months. 



Cultures. On agar, containing ascites fluid, it grows very spar- 

 ingly. The colonies are exceedingly delicate, and gray, turning 

 to yellowish, and are scarcely above the culture media. It will not 

 grow in gelatine, milk, or ordinary bouillon, but in one made of 

 nutrose, serum, beef-extract, and peptone. 



Habitat. Never found outside the human organism, except on 



linen, towels, instruments, etc. It is in all senses a strict parasite. 



Bacterial Activities. Apparently does not produce a soluble 



toxin, but an endo-toxin (gonotoxiri), which is highly resistant to 



heat. 



