PATHOGENIC BACTERIA. 309 



Diplococcus Intracellularis Meningitidis.* Found in 

 the exudate of cerebro-spinal meningitis by Weichselbaum; 

 isolated by Dunham t and others from the upper air passages 

 in such cases. 



Flexner J found that the reason for the rapid death and dis- 

 integration of the organism which takes place in 24 to 48 

 hours in the ice box and less quickly in the incubator is due 

 to an enzyme contained in the organism itself an autolytic 

 enzyme. 



FIG. 73. Diplococcus intracellularis meningitidis and pus-cells. (X 1000.) 



Flexner furthermore found that by using diluted serum of the 

 sheep instead of that of human beings in the agar medium, and 

 by the addition of a calcium salt (calcium carbonate) to this 

 sheep-serum-agar medium a given culture will remain alive 

 many weeks. 



Dunham and Ward, assisting Flexner, failed to find the or- 



* The writer is indebted for the brief statement which it is possible to give 

 here chiefly to the exhaustive Report to the Massachusetts Board of Health 

 by Councilman, Mallory and Wright, 1898. The photograph was made from 

 a preparation kindly furnished by Dr. Mallory. See also Davis Journ. Infec. 

 Dis. Vol. IV. 1907. pp. 558-681. 



f Journ. Inject. Dis. Sup. No. 2. Feb., 1906. pp. 10-20. 



t Journ. Exper. Med. Vol. IX. 1907. pp. 105-141. 



