MICROCOCCUS BICOLOB. 189 



growth upon potato. These characteristics are not sufficient for sepa- 

 rating it, especially as Heydenreich does not describe his potato cul- 

 tures as essentially different from those of the Micr. pyogenes. Kapt- 

 schewsky declares (C. B. vi, 504) the Micr. biskra identical with the 

 Micr. pyogenes, and prefers to consider a streptococcus as the cause of 

 the disease. 



Micrococcus of gangrenous mastitis in sheep, Nocard (A. P. I 417). 

 Staphylococcus haemorrhagicus, E. Klein (C. B. xxn, 81). 



De Jong's Staphylococcus bovis is said to be different from the 

 Micr. pyogenes. Injected subcutaneously, intraperitoneally, and in- 

 travenously it is pathogenic for rabbits, dogs, and guinea-pigs. 

 Neither its white nor its yellow form liquefies gelatin, in spite of 

 luxuriant growth ; milk is not coagulated ; in bouillon it forms a 

 delicate, tenacious sediment. 



The cause of a circumscribed falling of hair, without discolora- 

 tion of the hair-bed and without a tendency to spread, is found, 

 according to Vaillard and Vincent, in a white liquefying coccus, 1 // 

 in diameter, which corresponds throughout, in its growth, to the 

 Micr. pyogenes y albus (A. P. IV, 1890, 446). 



(Literature by Hollborn, C. B. xvm, 47, 108. ) 



Micrococcus bicolor (Zimmermann). 



Round cocci from 1.2 // to 1.6 p. Gelatin plate : At first yellowish, 

 succulent, elevated ; later, orange-yellow,, slowly sinking, oily looking 

 colonies of round form; besides these there are others about the same, 

 but white in color. Magnified sixty times they are even-bordered and 

 faintly granular. Gelatin stab: Superficial growth is white, with a 

 slowly forming cup-shaped liquefaction. The growth along the stab 

 is thread-like. Agar plate is like gelatin, and also presents gray and 

 yellow colonies intermixed. Arjar streak : Succulent, whitish or gray- 

 ish-yellow growth with orange-yellow islands and points. The surface 

 growth in the agar stab always presents more or less perfect gray and 

 orange sectors, from which it is often possible to obtain pure gray or 

 pure orange-colored growths, but which in following generations again 

 produce the two colors. Bouillon becomes diffusely cloudy with mod- 

 erate, firm precipitate. Milk becomes a little acid and remains fluid. 

 Upon 2fo peptone bouillon it forms a trace of H 2 S and indol. We 

 have obtained this organism, which was isolated by Zimmermann from 

 tap-water, from gastric contents. The Micr. cremoides Zimmer- 

 mann is very closely related to this. We were entirely unable to 

 differentiate the culture obtained by Zimmermann. 



Also, the Micr. aurantiacus Cohn, which we obtained from Krai, 

 is distinguished only by the absence of liquefaction. We have also 

 obtained from it white, orange, and striped cultures, which pass from 

 one into the other. 



At present we can give no other decisive characteristics of the Micr. 

 bicolor, aurnntiaciiSj and even of the Micr. candicans as differing from 

 the Micr. pyogenes except the pathogenic action in animals and absence 

 of liquefaction. 



