508 BACTERIOLOGY. 



formed foci may contain fully virulent cocci. But 

 lobar pneumonia is not the only form of pneumonia 

 in the production of which this organism is concerned. 

 It has been shown by Netter that more than one-half 

 of the cases of bronchopneumonia, whether primary or 

 secondary to some other disease, as measles and diph- 

 theria, both in children and adults, are due to the 

 micrococcus lanceolatus. The microscopical appear- 

 ances in bronchopneumonia are the same as in lobar 

 pneumonia, the only difference being, according to the 

 observations of Ribbert and Baumgarten, that in the 

 former the infective process is less extended, resulting 

 in the formation of a number of small foci instead of 

 the lung being attacked in toto. 



Beside the affections above mentioned, this micro- 

 coccus is associated with other pathogenic bacteria, 

 producing a secondary or mixed infection. In tuber- 

 culosis, for example, it is often found associated with 

 the tubercle bacillus, taking part with this organism in 

 the destruction of the tubercular tissue of the lungs. 

 Having once reached the lung it may penetrate to dif- 

 ferent organs in the body, producing in them more or 

 less intense inflammatory processes, which are mostly of 

 a purulent character. It may thus cause inflammations 

 of the serous membranes of the endocardium, the peri- 

 cardium, the meuinges, and even of the brain itself. 

 Foremost among the secondary infections which it 

 causes are meningitis, serofibrinous pleurisy, and em- 

 pyema. In 25 cases of purulent meningitis examined 

 by Netter the " pneumococcus " was found in 16; 4 of 

 these cases were complicated with purulent otitis, 6 

 with pneumonia, and 3 with ulcerative endocarditis. 

 In 45 cases collected by Netter from the literature of 



