eaih Fs 
FUNGI IN CHEESE RIPENING. 107 
and just as important that we know how to get rid and stay 
rid (if it be possible) of those we do not want. The discussion 
of the whole group will be reserved for another paper. Here 
we may describe in simple terms the two cheese fungi we find 
important, but it may as well be acknowledged at the outset 
that with the possible exception of the Camembert species, 
safe recognition of species without technical knowledge and 
cultural study is out of the question. 
THE CAMEMBERT MOLD. 
The spores of the Camembert mold grow rather slowly in 
comparison with the other molds of the group. ‘They first 
swell to nearly double size, then produce fine threads or hyphae 
at from one to three points on their surface. Upon a cheese 
or in laboratory culture the subsequent growth of these threads 
forms a colony large enough to be visible with the naked eye, 
in ordinary room temperature, in about two days. Usually in 
four or five days the colony will have become loosely white 
cottony, about one-half inch or less in diameter, and perhaps 
standing one-twentieth of an inch above the surrounding sur- 
face. At or about this stage the center of this colony begins 
to turn a shade of greenish grey, which is characteristic of 
this species, though one or two other forms produce colors 
closely resembling it except to one very familiar with the 
shades of color in question. ‘This is due to the presence of 
ripe spores. Upon the cheese in the cellar this color often does 
not appear in less than a week or even ten days. Microscopic 
examination shows that the submerged threads of mycelium of 
such a colony do not go deeper into the solid media than one- 
sixteenth of an inch, and that the superficial portion of the 
mycelium spreads as fast or nearly so as the part beneath the | 
surface of the substratum. This fungus grows and fruits for 
about two weeks, in some cases this may be prolonged to three 
weeks, and at the end of that period no further growth is to be 
expected from the primary colonies. Nor if the medium is un- 
disturbed is there a secondary growth from the germination of 
the spores produced by the first colony. In case the rind of 
the cheese is broken so that a fresh surface is presented, the 
spores will develop new colonies upon such areas. A colony 
then produces a single crop of spores and dies, under ordinary 
