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In general the colonies on meat-gelatine 1 °/, ureum or ammo- 
nium malate-gelatine 1°/, ureum are characterized by their small 
dimensions, whilst a field of calciumphosphate- and calciumearbonate- 
crystals surrounds them. 
After 5 or 6.days the titre has risen toa maximum of + 125 c.c.N. 
per 100 cc. of culture-liquid, so that + 4°/, ureum has been split. 
The 4 or 5 species present are the Urobacillus leubii (Brtserinck) 
and the most powerful species described by Mique, the Urobacillus 
maddoat, freudenreichit and duclauxii together with a species not 
yet described and not forming spores, which will be called wroba- 
cillus jakschit. 
After infection of cultures with ammoniummalate it is especially the 
Urobacillus maddori and wurobacillus duclauxi together with the 
Urobacillus jakschii which predominate. Sometimes the Urobacillus 
jakschu supplants the two other species almost entirely and is almost 
accumulated to pure cultivation. 
If we start from pasteurized material, it is especially the Urobacillus 
maddoati and Urobacillus duclauxii which make themselves con- 
spicuous. 
In these culture-liquid the Urobacillus pasteuri BrimrincK did not 
occur, so that the latter may be said to belong to the ureum- 
bacteria which positively want albumen for their growth. 
For the description of the Urobacillus leubit, freudenreichit, maddox 
and duclauxu it is sufficient to mention the chief characteristics. 
The Urobacellus jakschii, however, will be described more in details. 
Urobacillus lewbit (BrIJERINK). 
Urobacillus leubii, which generally occurs in the Vorflora of 
BEIJERINCK’s accumulation-experiments, is a little moving bar which 
can get oblong spores. 
On meat-gelatine with ammoniumearbonate it is difficult to distinguish 
this species from wrobacillus pasteurii. Inocculated from this medium 
on neutral meat-gelatine it grows into two species of colonies: viz. 
into yellow, troubled, thin colonies forming spores and into glassy, 
transparent colonies free from spores. 
The growth is, however, upon meat-gelatine with ammoniumcar- 
bonate much better than upon neutral meat-gelatine. - 
The spores can bear boiling heat and can be dried. 
Gelatine is not melted. 
In bouillon 6°/, ureum 2'/,°/, ureum is split in 4—5 days 
