114 MICROBES, FERMENTS, AND MOULDS. 
which appear simultaneously with the moulds, pene- 
trate deeply into the tissues, disintegrate them by 
feeding at their expense, and the putrid condition 
increases; then the decomposition changes its nature 
and becomes less intense. The putrefied matter is 
finally desiccated, and leaves a brown mass—a complex 
mixture of substances combined with water (hydro- 
carbons), and of fatty and mineral substances which 
gradually disappear by slow oxidation (Gautier). 
Pasteur has ascertained, from the microscopic 
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oral 
Fig. 61.—Bacilli of pu- 
irefaction (Rosenbach : 
much magnified ) Fig. 62.—Zoogtoea of Spirillum tenue. 
study of the phenomena which occur in an infusion 
of animal matter in process of decomposition, that 
microbes appear in it in the form of globules or 
short rods (Micrococcus, Bacterium termo, Bacillus, 
etc.), which are either free or collected in a semi- 
mucilaginous mass, to which the special name zoogloea 
was at first given (Fig. 62). These microbes rapidly 
deprive the liquid of all its oxygen. At the same 
time a thin layer of mucedinew and of bacteria is 
