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4
Grunde.> In no case has a determination of the fungi been made.
Cao (5), who made a special study of the genus Oidium, isolated
many »species»’ and demonstrated the abundance of pathogenic
and non-pathogenic Oidium forms in nature. He found species of
this genus in faeces from the following animals: sheep, calf, rat,
rabbit, chicken, and slug. ANKERSMIT (2), studying the bacterial
flora of cattle excrement reports colonies of moulds growing on
material plated from the reticulum of a cow, but whithout any |
determinations. WEIGMANN and WotrFF (69) found Penicillium
brevicaule repeatedly in the faeces of cow and attributes to this
fungus the peculiarity of giving the mustard taste to milk and
butter when cows are being fed on cabbage. WÜTHRICH and FREUDEN-
REICH (71) found Oidium lactis in faeces of* a cow fed on sour
potatoes. Hopre (29) reports the presence of »moulds and yeasts»
in the digestive apparatus of Cricetus frumentarius. In one case
the fungus was determined to be a Mucor.
2. Preparation of Media and Methods of Isolations.
Before taking up for consideration the results of the isolations
it seems advisable to give a few remarks on the technic employed
in taking samples, in obtaining pure cultures, etc. Needless to
say, all Petri dishes were carefully sterilized for three hours at
about 150° C. All other glassware, including test tubes, bottles
and flasks, was sterilized in the hot air sterilizer for about three
hours at 150° C. The media used in this investigation was (except
when otherwise stated) the one commonly in use in this laboratory
for the growing of all ordinary fungi, and referred to as potato
agar. In making this media 18—20 grams of agar-agar were
melted either in an autoclave or over a gentle fire. While this
was being done an average-sized potato was pared, sliced, and
boiled in about half a litre of water for half an hour. The liquid
was strained through a double thickness of cheese cloth and added
to the melted agar. To this mixture was also added a table-
spoonful of cane sugar and enough water to make a litre. When
these ingredients were thoroughly mixed the medium was put into |
test tubes and sterilized in the autoclave for 30 minutes at 20
pounds pressure.
In collecting the samples great care was exercised to exclude
every possible chance of contamination by fungous spores in the
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