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lacking, on the culture gelatin, the smoothly spreading border. In 
young broth gelatin cultures, the pigment fluoresces blue, and after 
some time a white precipitate forms in the gelatin. 
Examined auxanographically, KNO, as source of nitrogen proved 
to cause a feeble growth with mannite, a vigorous one with kalium- 
malate, citrate, malonate, succinate and tartrate, as well as with 
elucose and levulose. On the other hand no growth is seen with 
cane-sugar maltose, milk-sugar, and raffinose. 
In broth, with 2°/, glucose, this bacterium, like all fluorescents, 
produces acid. Broth with 2°/, cane-sugar, becomes however strongly 
alkaline, which is observed also in all other fluorescent secreting no 
invertin. 
This bacterium neither produces diastase, nor can it hydrolise indican 
or ureum. In broth it forms no sulphureted hydrogen and no indol. 
In its behaviour towards free oxygen it likewise corresponds with 
the fluorescents, i.e. with the cover-glass culture in the humid room, 
both motion and growth cause accumulation in the meniscus. 
This makes the bacterium strongly contrast with B. stutzert and 
B. vulpinus, whose motion figures show the spirillum type. 
As to the energy of its denitrifying power B. demtrofluorescens 
corresponds with B. stutzers. At the “tube experiment” with broth 
gelatin with O,1°/, KNO,, the bubbles form over the whole length 
of the tube, quite in the same way as with B. stutzeri. 
5. Accumulation of Bacillus vulpinus ne sp. 
Already in my introductory observations I remarked, that an 
accumulation experiment with full access of air, when using tartrate 
and nitrate, produced this species, but the accumulation obtained in 
this way was still very imperfect. By cultivating under partly 
exclusion of air, I succeeded in improving the experiment very much. | 
obtained this result by enclosing in the culture bottle with the liquid a 
determined volume of air, and reinoculativg from bottle to bottle under 
the same conditions three or more times. It is true that thereby not 
all other species are totally removed, but this is no obstacle to the 
recognition of B. vulpinis, whose colonies are extremely charac- 
teristic, possessing a quite unique brown-red pigment. 
The experiment is as follows: 
Into a bottle of 50 Cem. 1 to 2 grams of fresh garden soil is put, 
and further it is filled up with the following culture liquid, whilst 
leaving on air bubble of 2 Cem: Tap-water, 2 °/, Calcium-tartrate, 
Ont NOS, and 0:05 pO KAP O:. 
11% 
