cs,
it seems probable that accidental confusion with other organisms must
have occurred.

[Illustration: A MILK FILLING APPARATUS

FIG. 10--Where soured milk is handled on the large scale,
a special filling apparatus for bottles is desirable, and
the soured milk supply should be under cover as shown.
This apparatus is made by the Dairy Machinery and
Construction Company.]

Krannhals[52] succeeded in isolating ten different keffir bacteria among
which were several sporulating bacteria. Here too it is impossible to
attach any importance to the results, as the artificial preparation of
keffir, by means of these bacteria, was not attempted. Beijerinck[53]
studied the organisms constituting keffir grains and attached prime
importance to the occurrence of two organisms, viz., (_a_) a yeast,
_Saccharomyces kefir_, which was capable of inverting milk sugar by
means of an enzyme (lactase) and afterwards fermented the products with
the formation of alcohol and carbon dioxide, and also (_b_) a non-motile
non-sporulating bacterium, afterwards _Lactobac. caucasicus_. The
latter, when cultivated on gelatine, gave rise to tough warty colonies
about 1/40 in. diameter, and was regarded as one of the lactic acid
bacteria found in milk which has been incubated at 77 deg. to 90 deg. F.
and afterwards incubated at a higher temperature, 100 deg. to 104 deg. F.
Scholl[54] isolated three different organisms, of which a yeast inverted
milk sugar for the lactic acid bacteria, while _Dispora_ peptonised the
albuminoid matters.

Adametz[55] failed to isolate _Dispora_, and came to the conclusion
that ordinary lactic bacteria and yeasts played the most important part
in the fermentation.

Essaulow found in keffir grains six different organisms--yeast cells,
cocci, short thick bacilli, bent bacilli, long threads, and motile
bacteria. The two latter would seem to be _Bacillus subtilis_, while the
others may be regarded as _Bacterium acidi lactici_ (Hueppe), _Bacterium
aerogenes_, and _Streptococcus lacticus_ (Grotenfeldt). Pure cultures
were insufficient to produce keffir, while mixed cultures of _Bacterium
acidi lactici_ and yeasts were effective.

Freudenreich,[56] to whom we owe a record of very carefully executed
experiments, could not arrive at a satisfactory explanation of the role
of _Bacillus caucasicus_. This organism is described as being 5-6 mu long
and 1 mu thick, slightly motile, and possessing bright refractive spo