THE GINGER BEER PLANT. 281 
So early as 1857, M. Bail announced that the fungus, J/ucor 
mucedo, was able to transform sugar into alcohol by fermentation ; 
which assertion was correct, though he fell into error, according to 
Pasteur, in stating that it was metamorphosed during the process 
into ordinary yeast. Pasteur states, ‘these two plants should be 
profoundly distinct, and if divers authors have obtained them 
mixed one with the other in the culture of Mucor, it is no doubt 
because they were adventitiously sown with the beer yeast, the 
germs being abundant, particularly in the dust of the atmosphere 
of all laboratories where studies relative to fermentation are made.” 
The sub-aqueous growths of Mucorini are very interesting and 
instructive, showing, as they do, their adaptability to various and 
very diverse circumstances. With the ordinary aerial form every 
observer of these organisms is familiar: the long erect hyphz, bearing 
spherical capsules at their summit, filled with variously-shaped 
spores which easily germinate, their development being readily 
studied. The sub-aqueous growths are but little known, and it 
will be well here to borrow from Pasteur’s researches, which may 
be found in detail in his Ltudes sur la Bitre. 
Mentioning the Mucor ferment, he writes :—“ After an active life 
in contact with the air, or even with a limited quantity thereof, it 
can still live out of the direct action of this element. But when de- 
prived of oxygen there are apparently seen all the signs of alcoholic 
fermentation, that is to say, a notable proportion of sugar, relative 
to the weight of solid matter assimilated and fixed by the plant, 
decomposed into alcohol and carbonic acid gas, a decomposition 
which continues so long as active life remains in the submerged 
cells. Fermentation ceases absolutely, or continues in such a sub- 
