NOT DESCRIBED IN SECTIONS IV. AND V. 323 



Stains best with Loffler's solution of methylene blue ; does not stain by 

 Gram's method. 



Biological Characters. An aerobic and facultative anaerobic, non- 

 liquefying micrococcus. Grows very slowly at the room temperature not 

 below 20 C. In the incubating oven grows in the usual culture media. In 

 gelatin stick cultures a scanty development of small, white colonies occurs 

 along the line of puncture. Upon the surface of agar small, transparent 

 drops are developed along the impfstrich. \Jponpotato, at 37 C.. a thin, 

 broad, yellowish, shining layer is developed in the course of a few days 

 scarcely visible. Upon blood serum small, moist, transparent colonies are 

 developed. 



Pathogenesis. Pathogenic for rabbits and rats, which die in from six to 

 ten days after inoculation with a pure culture; the spleen is found to be en- 

 larged, the lungs hyperaemic, and a bloody serum is found in the cavity of 

 the abdomen ; the cocci are present in the blood in considerable numbers, 

 but are rarely seen in the red corpuscles. Inoculations in oxen, horses, 

 goats, sheep, guinea-pigs, and birds were without effect. 



35. MICROCOCCUS GINGIV^E PYOGENES. 



Obtained by Miller (1889) from the mouth of a man suffering from alveo- 

 lar abscess. 



Morphology. Large cocci of irregular dimensions, solitary or in pairs. 



Biological Characters. An aerobic and facultative anaerobic, non-lique- 

 fying micrococcus. Grows at the room temperature in the usual media. Upon 

 gelatin plates it forms spherical, well-defined colonies, which under a low 

 power are at first slightly colored and later opaque. In gelatin stick cultures 

 an abundant development occurs both upon the surface and along the line 

 of puncture. Upon the surface of agar a tolerably thick, grayish growth 

 occurs along the impfstrich, which has a purplish tint by transmitted light. 



Pathogenesis. Subcutaneous injections in mice produce a local abscess 

 and necrosis of the skin, followed sometimes by death. Injections into the 

 cavity of the abdomen produced peritonitis and death in from twelve to 

 twenty-four hours. 



36. PSEUDODIPLOCOCCUS PNEUMONIA. 



Obtained by Bonome (1888) from the sero-fibrinous exudate in an autopsy 

 of an individual who died of cerebro-spinal meningitis. _ 



Morphology. Oval cocci, in pairs or in chains of five or six elements, 

 often surrounded by a transparent capsule; not to be distinguished from 

 Micrococcus pneumoniae crouposae. 



Stains with the usual aniline colors and by Gram s method. 



Biological Characters. An aerobic, non-liquefying micrococcus. Grows 

 in the usual culture media at the room temperature (Micrococcus pneumonias 

 crouposae does not grow at the room temperature) . In gelatin stick cultiires 

 very small colonies are developed along the line of puncture at the end Of 

 twenty-four to twenty-eight hours. Upon the surface of agar a rather 

 scanty, moist layer is developed along the impfstrich. Upon potato a thin, 

 scarcely visible layer is developed. In bouillon tine development is abun- 

 dant; the culture medium acquires a very acid reaction and gives oil a strong 

 odor like that of perspiration. . 



Pathogenesis. Pathogenic for mice, guinea-pigs, and rabbits, in wnicn 

 animals it produces fatal septicaemia; the spleen is not enlarged, as is the 

 case in animals inoculated with Micrococcus pneumoniae crouposae. 



37. STREPTOCOCCUS SEPTICUS LIQUEFACIENS. 



Obtained by Babes (1889) from the blood and various organs of a child 

 which died of septicaemia following scarlatina. 



