104 STUDIES ON FERMENTATION. 



than -jjyyj of a millimetre (nearly y-VTr i^O i^ diameter, we per- 

 ceived much larger ones, swollen and contorted in the 

 most singular manner, and measuring as much as -y'-^ of 

 a millimetre across their broadest parts. There was also a 

 multitude of the ordinary spores of aspergilhis mixed with 

 others of larger size, and big, inflated cells, with irregular or 

 spherical protuberances, full of granular matter. As there are 

 all the stages between the normal spores of the plant and the 

 big cells, and between these latter and the filaments, it must be 

 admitted that the whole of this strange vegetation results from 

 spores which change their structure under the influence of 

 special conditions to which they are exposed.* Beyond all 

 doubt these cells and irregularly shaped segments, in vegetating 

 with difiiculty, gave rise to the fermentation, which, although 

 insignificant, was sufficiently marked to produce more than a 

 gramme (15 grains) of alcohol. The oxygen of the air failing, 

 or existing in insufficient quantity for the regular develop- 

 ment of the filaments of mycelium belonging to the plant, and 

 for the germination of its submerged spores, filaments and spores 

 vegetated as the yeast of beer might have done if deprived 

 of oxygen. 



If we study the vegetation of as^ycrgillus glaucus with this 

 preconceived idea, we shall soon recognize the fact that these 

 spherical forms of mycelium are the result of a greater or less 

 deprivation of air. The filaments of this mycelium which 

 develop freely in the aerated liquid are young and transparent, 

 small in diameter, and exhibit the ordinary ramifications. 

 Those which are situated about the centre, in the denser or 



* Since -writing the above we have experienced some doubt as to 

 whether the forms of development represented in Fig. 20 are actually 

 those of the aspergilhis glaucus, which we supposed our fungoid growth 

 to be. In some of the later sketches of our observations we find similar 

 forms, which belong to a bluish kind of peniciJHum, with rather large 

 spores. Fortunately, this doubt affects our argument in no essential 

 particular. It matters very little what variety of fungoid growth it is 

 that gives rise to alcoholic fermentation attended by peculiarities of shape 

 that only occur in the development of its spores when air fails it. 



