28 INFECTION AND IMMUNITY. 



organs or groups of organs to be involved in some 

 particular manner. These are features which, 

 together with a constant bacteriology, stamp them 

 as specific diseases. On the other hand, a large 

 number of micro-organisms cause no well-defined 

 clinical and anatomic disease, but, depending on 

 various accidents, cause an inflammation now in 

 one organ, now in another. 



Eegarding the production of suppuration, the 

 pyogenic power is common to a large number 

 of microbes. A diphtheritic or pseudo-diphtheri- 

 tic process in the mouth and throat may be caused 

 by the diphtheria bacillus, streptococcus, staphylo- 

 coccus, oidium or yeasts ; bronchitis may be caused 

 by the influenza, tubercle, plague and typhoid 

 bacilli, and by the infecting agents of the acute 

 exanthemata, etc. ; pulmonitis by the pneumococ- 

 cus, streptococcus, tubercle, plague, Friedlander 

 and influenza bacilli, oidium, actinomyces, etc.; 

 meningitis by the tubercle and influenza bacilli, 

 streptococcus, staphylococcus, pneumococcus, gono- 

 coccus, diplococcus of epidemic meningitis, the 

 syphilis virus, etc. ; arthritis by the streptococcus, 

 staphylococcus, tubercle bacillus, gonococcus, the 

 virus of rheumatic fever, etc. ; endocarditis by the 

 streptococcus, staphylococcus, gonococcus, pneu- 

 mococcus, tubercle bacillus, etc., and septicemia 

 by a whole host of organisms aside from those 

 mentioned as causing specific diseases. 



Within certain limits, however, there is often a 

 degree of specificity in the processes produced by 

 some of the organisms mentioned, which some- 

 times allows of clinical and anatomic differentia- 

 tion. The infiltrating and rapidly extending in- 



