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 



^8V,)_ 



"I 



<? l* 



Fig. 61. Bacilli of pu- 

 trefaction (Rosenbach: 

 much magnified) Fig. 62. Zoogloea 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 mucedinece and of bacteria is 



