154 ESSENTIALS OF BACTERIOLOGY 



Form. A small coccus occurring in pairs, flattened against 

 each other, and contained within the leukocytes. 



Properties. Ferments sugars, with acid production. 



Growth. Best in blood-agar, serum-agar, and ascitic glucose- 

 agar at body temperature in twenty-four hours. 



Colonies. Circular discs, almost transparent under low 

 power; margins smooth. 



Fig. 89. Diplococcus intracellularis meningitidis in leukocytes. Cover- 

 glass preparation from peritoneal exudate in a guinea-pig (x 2000) (Wright 

 and Brown). 



Stain. With basic anilin. Gram negative, resembling 

 gonococcus. 



Patho genesis. Causes epidemic cerebrospinal fever, prob- 

 ably by infection through the nasopharynx; the organism is 

 found in the spinal fluid and in other inflammatory exudates, 

 and can be examined in fluid by lumbar puncture. 



Ordinary laboratory animals immune, but Flexner has 

 succeeded in inoculating monkeys. 



