CHAPTER XXVII 



FLOWERLESS PLANTS {Continued) 



Moulds, Mildews, Yeast, Bacteria 



If we have studied the mushrooms and have seen 

 the mycelium, it will be an easy step to understand the 

 moulds, and from these, through the familiar yeast plant, 

 we may pass to the study of the bacteria. We shall not 

 have far to seek for specimens of moulds and mildews. 

 We may find them too often on plants and trees that we 

 are trying to rear. After a period of wet weather they 

 may cover the books on our shelves, the clothes in our 

 closets, — not to speak of the eternal vigilance necessary 

 to prevent them from appropriating any food that is not 

 sealed against their attacks. While many may be inclined 

 to consider them too minute for elementary lessons, in 

 the mass they are easily seen, and their relation to proper 

 sanitation of the home and to fungous diseases of plants 

 makes them an essential part of the plan for nature study. 

 As a whole, too, the group plays a necessary and benefi- 

 cent role in nature. 



Moulds. — A jelly glass, or even a medicine vial, furnishes 

 ample room for a garden of these instructive plants, and 

 they may be cultivated on almost anything for soil. First 

 we will take some kind of liquid culture medium in which 

 we can see all the different parts of the mould plant as it 



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