324 PATHOGENIC MICROCOCCI 



Morphology. Micrococci, about 0.3 to 0.4 /* in diameter, in pairs or in 

 short chains in which the elements are loosely connected. 



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



Biological Characters. An aerobic, liquefying micrococcus. Grows in 

 the usual culture media at the room temperature. In gelatin stick cultures 

 at the end of twenty-four hours a thin, granular, whitish stripe is seen along 

 the line of puncture, while the surface seems somewhat depressed; later 

 liquefaction of the gelatin occurs in funnel form ; the liquefied gelatin is but 

 slightly clouded, and upon the walls of the funnel peculiar, flat, white, leaf- 

 shaped, jagged colonies are seen. Upon the surface of agar, at 36 (1, small, 

 white, tnin, shining, transparent colonies are developed, which may attain 

 a diameter of two to three millimetres. Upon blood serum a scarcely visible 

 granular layer is developed. 



Pathogenesis. Subcutaneous injections in mice and rabbits produce 

 local inflammation with oedema, and death occurs in about six days ; the 

 streptococci are found in large numbers in the effused serum, in the blood, 

 and in the spleen. After being cultivated for some time in artificial media 

 the cultures lose their pathogenic power. 



38. MICROCOCCUS OF KIRCHNER. 



Obtained by Kirchner (1890) from the bronchial secretions (in sputum) of 

 patients suffering from epidemic influenza soldiers in garrison at Hanover. 



Morphology. Spherical cocci, usually associated in pairs, and surrounded 

 by a capsule. Distinguished from Micrococcus pneumonias crouposae by be- 

 ing smaller, quite spherical, and the elements in a pair being more widely 

 separated from each other. Found in the bronchial secretion in scattered 

 pairs, or associated in groups ; occasionally seen in chains. 



Stains with the usual aniline colors, but not by Gram's method. 



Biological Characters. An aerobic micrococcus; does not grow in flesh- 

 peptone-gelatin at the room temperature. Upon agar plates, at 36 p., 

 small, grayish-white, transparent, spherical colonies are developed, which 

 later form round, grayish-white plaques. In agar stick cultures an abun- 

 dant development occurs upon the surface, extending to the walls of the 

 test tube ; growth also occurs along the line of puncture. 



Pathogenesis. Not pathogenic for rabbits or for white mice. A guinea- 

 pig which received one cubic centimetre of a bouillon culture in the pleural 

 cavity died at the end of twenty-four hours ; the spleen was not enlarged ; 

 lungs hyperasmic ; the micrococci were found in the blood and in the vari- 

 ous organs. Another guinea-pig, which received one cubic centimetre of a 

 bouillon culture in the cavity of the abdomen, recovered after a slight indis- 

 position. 



39. MICROCOCCUS NO. II. OF FISCHEL,. 



Obtained by Fischel (1891) from the blood of two cases of influenza. 



Morphology. Micrococci of from 1 to 1.25 u in diameter, mostly in 

 pairs, sometimes in chains. 



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



Biological Characters. An aerobic and facultative anaerobic, liquefy- 

 ing micrococcus. Grows in the usual culture media at the room tempera 

 ture. Upon gelatin plates minute colonies, visible only under the micro- 

 scope, are developed at the end of three days. In gelatin stick cultures an 

 abundant milk-white growth occurs along the line of puncture, and lique- 

 faction of the gelatin commences at the end of four days ; this progresses 

 slowly. Upon agar plates, at 37 C., superficial colonies are developed re- 

 sembling a drop of milk. Upon potato, at 37 C., at the end of eight days a 

 thin, shining layer of a yellowish-white color, and about one centimetre 

 broad, is developed; no growth upon potato at the room temperature. No 

 growth occurs in liquid blood serum or in milk. In sterilized water this 

 micrococcus is said by Fischel to lose its vitality in eight hours. 



