PATHOGENIC BACTERIA. 255 



It is moderately pathogenic for guinea-pigs and rabbits 

 when inoculated into the pleura or peritoneum. Meningitis 

 and encephaHtis have been produced in the dog and goat by 

 inoculation in the meninges. 



This organism appears to be the principal if not the only 

 cause of epidemic cerebro-spinal meningitis. The lesion con- 

 sists of a purulent inflammation of the pia and arachnoid, 

 extending into the brain-substance, over the cord and along 

 the nerves. General invasion of the tissues of the body seems 

 not to occur, but focal areas of pneumonia may be present. 



V 



% 



Fig. 68. — Diplococcus inteacellularis meningitidis and Pus-cells. 



(X 1000.) 



Spinal puncture in the lumbar region is recommended as a 

 means of diagnosis. The puncture should be made early, 

 and the fluid should be examined with the microscope and by 

 cultures. 



Micrococcus gonorrhoeae (Gonococcus of Neisser). — Found 

 in pus in cases of gonorrhea. The micrococci generally are in 

 pairs, occasionally in groups of four. The cocci are flattened, 

 the flattened sides facing each other, and they are often com- 

 pared to a pair of biscuits. The long diameter of the pair of 

 biscuit-shaped elements is about 1.25 //. The organisms are 



