has isolated
an acidophilic organism from the dejecta of infants which resembles
closely, both in manner of growth, resistance to acids, true branching,
and temperature optimum, the granule bacillus and related forms.

[This group of sixteen illustrations (Figs. 14 to 29), showing various
aspects of the Yoghourt bacillus and others of a cognate nature, is
taken from the _Centralblatt fuer Bakteriologie_ of Jena.--L. M. D.]

[Illustration: FIG. 14.--Granule Bacillus from Yoghourt.
Shredded preparation of a fresh skim-milk culture at 37 deg.
C. for six hours. Stain: aqueous methylene blue. (Enlarged
1:500.) In Figs. 15 and 17 will be noticed the chain
arrangement of the bacillus, which, in spite of the
supposed data of Luerssen and Kuhn, will be generally
noticed in the granule bacillus.]

[Illustration: FIG. 15.--Granule Bacillus from Yoghourt,
cultivated after the usual Agar method, for twenty-four
hours at 37 deg. C. Stain: aqueous methylene blue. (Enlarged
1:500.)]

[Illustration: FIG. 16.--Granule Bacillus from Yoghourt.
Agar Milk Sugar Culture cultivated for forty-eight hours
at 37 deg. C. Below is the true branching, above, the
distorted involution form. This production of involution
forms occurs chiefly in old cultures, and is an indication
of degeneration. Stain: aqueous methylene blue. (Enlarged
1:700.)]

[Illustration: FIG. 17.--_Bacteria W._ from Milk,
cultivated twenty-four hours at 37 deg. C. Methylene blue.
(Enlarged 1:500.) The similarity in the pictures ought to
serve as a proof of the near relation of the granule form
and non-granule varieties.]

[Illustration: FIG. 18.--Agar Milk Sugar Culture. From the
original Bulgarian Yoghourt. In the centre, and beneath,
the characteristic hairy irregular colonies of the granule
bacillus (_Bacillus bulgaricus_ group), to the left, the
smooth contoured yeast colonies. The colonies of the
former organism always remain microscopic in size.
(Incubated several days at 20 deg. to 25 deg. C. Magnified X 10.)]

[Illustration: FIG. 19.--Agar Milk Sugar Culture. Surface
colony of granule bacillus from calf's stomach. The great
resemblance this colony bears to those formed by the
granule bacillus from Yoghourt will be apparent. This
fact, as well as close agreement in other cultured
features, induced Kuntze to place these organisms in one
group. (Incubated two days at 37 deg. C. Magnified X