268 IMPORTANT VARIETIES OF FISSION-FUNGI. 



Bacterium erythrogenes. (Qrotenfelt.) Lehm. and 



Neum. 



Bacillus lactis erythrogenes Grotenfelt. Bacillus of red milk. 

 Literature: Grotenfelt (Fortschritte der Mediz., 1889, vii, 41) and A. 

 Baginsky (C. B. vi, 137). 



Non-motile, short rods, 0.8-3.0 // long and 0.5-1.0 u thick. Stains 

 by Gram's method. Upon the gelatin plate, grayish-yellow, roundish 

 disks, which gradually sink into the gelatin and liquefy it. When 

 magnified 60 times, at first both the superficial and deep colonies 

 resemble very much those of the Bact. coli; later, when liquefaction 

 begins, the border of the colony, now having become opaque, is 

 beset with fine hairs, and later appears irregularly eaten out and 

 coarsely granular. The intensity of liquefaction is decidedly variable 

 in different colonies. Upon the gelatin stab there develops a sulphur- 

 yellow, thick, slowly sinking growth; later the liquefaction is cylin- 

 dric. The surface growth upon agar is yellow and moist. Agar and 

 gelatin (especially in the dark) become colored intensely rose-red to 

 garnet. Our cultures also did so in diffuse daylight. According to 

 Grotenfelt, the pigment presents two lines between D and E, and one 

 in the blue portion of the spectrum. Potato culture is sulphur-yellow, 

 elevated, partly dull and partly moist. The cream separates from 

 milk (cream, yellow), the casein forms a flocculent precipitate (with 

 alkaline reaction), the clear serum becoming rose-red. No gas is 

 formed from grape-sugar. From bouillon there is formed abundant 

 indol, but little H 2 S. Our description is from a culture obtained from 

 Krai. 



Bacterium helvolum. (Zimm. i, p. 52.) Lehm. and 



Neum. 



Plump, rather thick, short rods (1.0-3.6 u long, 0.8-1.2 fi thick), 

 non-motile, staining by Gram's method. Gelatin plate : Colonies are 

 roundish, lively lemon yellow, flatly elevated, and later they sink in 

 the gelatin. When magnified 60 times : homogeneous, hardly at all 

 transparent in the middle, clearer at the edges, border smooth, and 

 with beginning liquefaction the sharp border becomes slightly 

 crumbly. 



Upon the gelatin stab culture a luxuriant, shining, intense lemon- 

 yellow growth, which slowly sinks into the medium. Agar culture : 

 yellowish-gray, moist. Potato culture : dull, broad, greenish -yellow. 

 Bouillon becomes cloudy, with a delicate pellicle. Abundant forma- 

 tion of H 2 S, but none of indol. No gas is formed from grape-sugar. 

 Milk is coagulated. 



We obtained an organism from air which corresponded exactly with 

 Zimmermann's description. Bacillus luteus Flugge appears identical, 

 except that liquefaction is absent. Also the following appear very 

 closely related : the non-liquefying Bac. constrictus Zimmerman n 

 (I, p. 42) and the Bac. subnavus Zimmermann (I, p. 62). 



