1/4 BACTERIOLOGY. 



jected, suppurating nephritis with ensuing 

 septicaemia occurs. 



Inflammation of the membranes of the brain 

 can be produced by various bacteria, such as 

 Frankel's pneumococcus, the streptococcus of 

 erysipelas, tubercle bacilli and B. coli corn- 

 munis. However, Weichselbaum and later, 

 H. Jager, have made it appear probable 

 that the epidemic form of cerebro-spinal men- 

 ingitis is caused by a particular species, the 

 Diplococcus intracellularis. These bacteria 

 stain by Gram's method, both in cultures and 

 in preparations from the tissues, but in sections 

 become decolorized ; they form capsules, and 

 are cultivated more easily than the lancet bac- 

 teria. White mice proved refractory to in- 

 oculation. The experiments with the organism 

 are not yet complete enough to be altogether 

 convincing. 



The bacteria of influenza were discovered by 

 R. Pfeiffer in 1891. They are even somewhat 

 smaller than the bacilli of mouse septicaemia, 

 about two to three times as long as they are 

 thick, without capsules, and are decolorized by 

 Gram's method. They grow in the form of very 

 fine glassy drops, and succeed best upon blood- 

 serum or blood-agar or when haemoglobin is 

 added to the medium. A similar bacillus, which 

 can be cultivated more easily and is called the 



