520 BACTERIA IN INFECTIOUS DISEASES NOT PROVED 



very delicate, almost transparent colonies developed ; they were of a pearl- 

 gray color ; with an irregular, rosette-like margin ; in the course of several 

 weeks they attained a diameter of one to one and one-half millimetres. 

 Upon potato a scanty, grayish- white, dry layer is developed. Under the 

 most favorable conditions the development was very slow not more rapid 

 than that of the tubercle bacillus. 



EMPYEMA. 



A. Frankel (1888), as a result of his bacteriological studies in 

 twelve cases of empyema, divides the cases into four groups. In 

 one group of three cases Streptococcus pyogenes was the only micro- 

 organism obtained in his cultures or seen in stained preparations of 

 pus from the pleural cavity. In a second group of three cases, oc- 

 curring in the course of a pneumonia, the only microorganism pre- 

 sent was " diplococcus pneumonias " (Micrococcus pneumonias crou- 

 posae). The third group included four cases of tubercular empyema ; 

 in one of these tubercle bacilli only were found in pus from the 

 pleural cavity, in one case streptococci were found, and in two no 

 microorganisms were found. In the fourth group of two cases the 

 empyema resulted from the opening of an abscess into the pleural 

 cavity, and streptococci were found in the pus. 



Xetter, in a series of forty-six cases examined by him, found 

 Micrococcus pneumonias crouposas in fourteen. Koplik (1890) found 

 the same microorganism in seven cases examined by him, and Strep- 

 tococcus pyogenes in two cases. 



ENDOCARDITIS. 



The experimental evidence relating to endocarditis is similar to 

 that in cystitis. The injection of the microorganisms found attached 

 to the diseased structures into the circulation of lower animals does 

 not produce endocarditis unless the valves have been previously in- 

 jured by mechanical violence or by chemical irritants. If some 

 doubt remains among pathologists as to the etiological relation of the 

 microorganisms found, the serious secondary results of the mycotic 

 invasion are well established. In a series of twenty-nine cases 

 studied by Weichselbaum (1885-1888) the following results were ob- 

 tained : In eight the result of culture experiments and microscopical 

 examination was negative; in seven "diplococcus pneumonias"' 

 (Micrococcus pneumonias crouposas) was found ; in six Streptococcus 

 pyogenes ; in two Staphylococcus pyogenes aureus ; in two Bacillus 

 endocarditidis griseus (Weichselbaum) ; in one Micrococcus endocar- 

 ditidis rugatus (Weichselbaum) ; in one Bacillus endocarditidis cap- 

 sulatus (Weichselbaum) ; in two cases a bacillus which he did not 

 succeed in cultivating. For further details see the descriptions of 

 microorganisms referred to. 



