770 
Staining peculiarities: The microbe stains easily with the ordinary 
dyes for bacteria. After Gram the small rods show polar coloration, 
positive or negative, according to the medium; the comma-shape always 
positive, the body of the granular rods negative, the granules positive. 
After Mucn’s modification of Gram’s methods the results agree 
with those obtained with the Gram-stain. 
With Zieur’s stain they are not acid-fast. 
The microbe is facultative anaërobe, however it grows much better 
in presence of oxygen. Growth is sluggish in deep stab-cultures, 
covered with agar, and in a hydrogen-atmosphere. 
Influence of temperature on the growth. 
The growth optimum is in the neighbourhood of 32° C. 
The highest temperature at which growth is demonstrable is 39° C. ; 
at 40° C. it ceases altogether. 
The lowest possible temperature for growth is between 10° and 
Ber Ata Okri iis non-existent: 
Reaction of media: alkaline reaction is more conducive to growth, 
which however is not inconsiderable with acid reaction. 
Growth. 
Gelatin-stabeulture: not liquefacient, slight growth in 
the track made by the needle, threadlike, getting thinner 
lower down. 
Smear-culture: growing evenly in moderate amount. 
Plate-culture (after 24 hours): cultures elevated on the 
surface, dark grey (later greyish-yellow to ochraceous), round, 
smooth-rimmed, homogeneous, dewdrop-shaped, dim-glistening. 
Later on the colonies are finely granular and the edge gets 
finely crenated. 
Agar-stabculture: slight growth in the track, threadlike, 
ragged, getting thinner lower down. 
Smear-culture: growing evenly in fair amount. 
Plate-culture (after 24 hours): cultures elevated on the 
surface, yellowish, round, smooth-rimmed, somewhat granulous, 
granules finer near the rim than in the centre, where a dark 
stain is visible, dewdrop-shape, highly glistening, condensation 
water cloudy, no pellicle is formed. 
Ascitesagar-plateculture: sluggish and slight growth ; 
colonies finely granular, later here and there more coarsely 
granular especially at the periphery, so that the rim, being 
smooth at first, now becomes finely lobulated; elevated above 
the surface; fluorescence. 
