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Scientific Memoirs by

thick, yellowish strata, with a few more prominent masses. It had no perceptible
smell. No commas could be found, the growth apparently consisting entirely of
large, straight Bacilli

     EXPERIMENT IV.—One hundred grammes of dry garden-earth were triturated
with about thirty grammes of fresh fæcal matter and the mixture set as usual in
a covered beaker. The fæcal matter was neutral in re-action. Forty-eight hours
later the earth appeared to be everywhere penetrated by white fungal hyphæ,
and on the surface a crop of young sporangia, of a species of mucor, had begun to
appear. Fifty cubic centimetres of neutral salt solution full of the commas from
two tube-cultivations of forty-eight hours' growth were now poured over it and
the beaker again set aside. Two days later a stratum of brownish alkaline
fluid, with a distinct thin scum, was still present on the surface. Some of this,
and some of the surface earth, were mixed with neutral salt solution and a plate-
cultivation of it set as usual. On the following day this had a sickly, somewhat
choleraic smell. The surface was covered by yellowish and bluish colonies, and
full of small interstitial ones. Six preparations were mounted, and in two of them
commas were present.

     Six days after the addition of the commas to the earth another plate-
cultivation was started. Forty-eight hours later it was crowded with concrete
yellowish colonies, and also contained some large, diffused patches of yellowish
and bluish colour. The smell was non-choleraic and like that of the flowers
of Bassia latifolia. Twelve preparations were mounted, but none of them con-
tained commas.

     Eight days after the commencement of the experiment another plate-cul-
tivation was inoculated from the earth. On the following day it had a faint
non-choleraic smell and was crowded with concrete colonies. Some diffuse
patches, of yellowish and bluish colour, were also present. Twelve preparations
were mounted from colonies which in any way resembled colonies of commas,
but none of them contained commas. Two days afterwards the cultivation had
a strong smell of bats. Another set of preparations was mounted, but, as before,
contained no commas.

     EXPERIMENT V.—Twenty-five grammes of fresh fæculence was triturated
with seventy-four grammes of dry garden-earth. Water was then added and
the mixture thoroughly stirred up and boiled over a Bunsen flame until nearly
dry. It was then transferred to a clean glass beaker and the latter set in a
boiling water-bath for half an hour. On the next day the beaker was kept in the
bath for an hour, and the same process was repeated on the two following ones.
At this stage of the experiment a plate-cultivation was inoculated from the soil
by the usual method. On the following day it was found to be full of
yellowish defined, circular colonies. The smell was faint and non-choleraic. Pre-
parations showed that the colonies were apparently all composed of a short,
thick, straight Bacillus. Twenty-four hours after the previous heating the beaker