300 MANUAL OF BACTERIOLOGY. 



him by Buxton. The streptococcus was grown in beef-broth 

 for ten days and the culture then inoculated with B. prodigiosus 

 and the mixed culture grown for another ten days. These cul- 

 tures, sterilized at 60° C, were injected into the tumors without 

 filtering. 



Streptococcus of Erysipelas. — The cause of erysipelas is 

 a streptococcus which in all essential respects — in its mor- 

 phology, its growth on culture-media, its behavior with stains 

 audits pathogenic properties — corresponds to the Streptococcus 

 pyogenes. It is probable that these organisms are identical, 

 though the clinical manifestations in erysipelas are sufficiently 

 characteristic to justify the clinician in making a distinction 

 between this on the one hand, and the other manifestations of 

 streptococcus infection on the other. In erysipelas, conta- 

 giousness is a most marked feature. 



Micrococcus Tetragenus.— Found in the cavities in the 

 lungs of pulmonary tuberculosis, in sputum and in pus. The 

 micrococci are enclosed in a transparent capsule, best seen in 

 preparations from the tissues of inoculated animals, and are 

 arranged in pairs or in fours; about i ^ in diameter; not motile; 

 stain by Gram's method. It grows well at the room tempera- 

 ture, but rather slowly; is a facultative anaerobe; does not 

 liquefy gelatin. Gelatin plates show little, white, punctiform 

 colonies, which, with the low power, are finely granular, and 

 have a peculiar glassy shimmer; in stab-cultures the growths 

 appear as little colonies along the line of puncture. On agar, 

 round white colonies form, which do not tend to spread. It 

 produces a thick, slimy film on potato and a broad, white, 

 moist growth on blood-serum. This organism is only oc- 

 casionally found in pus. It is pathogenic for white and gray 

 mice and guinea-pigs, but not for rabbits. It may produce 

 septicemia or only a localized suppuration in guinea-pigs. In 

 white mice general septicemia results on inoculation and the 

 Micrococcus tetragenus is found in the blood and in the great 



