THE PNEUMO-BACILLUS 491 



Milk is curdled, and the organism is an active fermenter of 

 many carbohydrates with gas formation ; the fermenta- 

 tion reactions are given in the table, p. 454. 



Pathogenic action. The pneumo-bacillus is pathogenic 

 to mice and guinea-pigs, but rabbits are immune. Post- 

 mortem, the spleen is enlarged, the lungs are congested 

 and consolidated in patches, arid the organism is found 

 in large numbers in the blood. In a small percentage 

 of cases of croupous pneumonia Friedlander's bacillus 

 may be associated with the 8. pneumonice. Friedlander's 

 bacillus may sometimes induce a primary broncho- 

 pneumonia, as in a series of 411 cases recorded by 

 Zander. 1 The onset in these cases was not sudden, 

 as is the rule in croupous pneumonia, but was preceded 

 by a prodromal stage of malaise, lasting one to two 

 days. It also causes bronchitis and bronchial and 

 other catarrhs of the respiratory tract, and is occa- 

 sionally associated with anginal conditions, which are 

 characterised by the formation of a false membrane, with 

 an absence of any general symptoms. A microscopical 

 examination of the membrane will show the organisms 

 surrounded with a capsule and unstainable by Gram's 

 method. If a culture be made on serum, the large, round, 

 greyish colonies of the bacillus will be recognisable in 

 fifteen to twenty hours, and should be examined micro- 

 scopically. To obtain a pure culture a white mouse 

 should be inoculated from a colony ; it will die in twenty- 

 eight to sixty hours. Friedlander's pneumo-bacillus has 

 also been met with in water by Grimbert. According to 

 him, it is identical with the B. capsulatus of Mori. 



Streptococcal Pneumonias 



Streptococcal broncho-pneumonia is occasionally primary, but 

 is commonly secondary to measles, influenza, whooping-cough, 



1 Deutsche med. Wochenschr., 1919, Bd. 45, p. 1180. 



