24 THE ORGANISMS OF FERMENTATION 



plant), such fungi are designated parasitic ; but if, on the other hand, they 

 utilise inanimate (or defunct) organic material, they are known as saprophytes. 



The parasites proper may be divided into two groups : strict or obligate 

 parasites, which are restricted to living animals or vegetable bodies, and facul- 

 tative parasites, which will also thrive on suitable inanimate substrata, and can 

 therefore be cultivated on artificial nutrient media. 



This latter group forms the connecting link between Pathological and 

 Technical Mycology. The former science regards these, together with the 

 obligate parasites, as the causes of disease, whilst conversely Technical Mycology 

 is interested in the facultative parasites on account of the decompositions they 

 induce in artificial media, i.e. outside the animal or vegetable economy. This 

 interest is, however, purely scientific, since, for hygienic reasons, the use of 

 parasitic ferments for practical technical purposes is precluded. 



The true interest of the technicist in the domain of Mycology is exclusively 

 centred in the non-parasitic ferments, and these alone form more especially the 

 subject of the present work, the first volume being devoted to the Schizomyceles, 

 and the second to the Eumycetes. 



