CHAPTER XIII 

 YEASTS AND MOLDS 



The organisms commonly designated as yeasts and molds, though not 

 belonging to the bacteria (Schizomycetes), are of the greatest importance 

 in human economy and play a most active part in life. Some of them 

 are most beneficent while others are very injurious to health. The yeast 

 organisms (Saccharomyces) cause the alcoholic fermentations in saccharine 



PIG. 69. Development of Mucor mucedo. a, b, c, d, stages in the formation of the 

 zygospore; d, mature zygospore; e,f, endospore formation; g, endospores; h, germinating 

 spore, this develops and finally gives rise to new zygospores; , mucor slightly magnified. 

 This mould is found on stale bread, damp leather, gloves, etc. 



solutions. Many of the mold group cause skin and other diseases. 

 They all belong to the plant division fungi. The more important species 

 may be grouped under three orders, as follows: 

 I. Phycomycetes. (Zygomycetes.) Zygospore formation. 



1. M ucor corymbifer. \ . , , . . . , . 



, . J , J } Both are found in tissue infections. 



2. Mucor mucedo. J 



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