INDEX. 207 



Y 



Yeast, an organised ferment, 171. 



Zea MAIS, Solerenohyma in, 41. 



Zygnenaacese, see Spirogyra. 



Zygospore, see Reproduction in fungi, 147. 



Zygote, of Spirogyra, 148. 



Zymogens, as precursors of enzymes, 158, 159. 



h\£l 



J 'I 



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