690 



THE NATURE BOOK 



heads come myriads of ripe spores, and 

 so minute and light are these non-sexual 

 spores (which, as I have previously 

 explained, are but minute constrictions 

 of the reproductive branches of the 



examples of similar but more malignant 

 organisms. 



When, ho\ve\-er, the spores that float 

 in the atmosphere settle upon an ex- 

 posed article of food or some moist organic 





l> 



# : 



W' 



••> 



♦a^ ' , 



i^r 



:.^ 



.B* 



. ■''m 



BLUE MOULD ON CHEESE. 

 (Magnified 60 diameters.) 



hyphcB) that they are removed from 

 the spore-heads by the slightest l^reath of 

 air. The air we breathe often contains 

 large numbers of such tiny spores ; thus 

 the smell of mouldiness is a sufficient 

 indication to us that, in all probal)ility, 

 we have inhaled several hundreds of 

 these invisible mould germs. Usually, 

 when thus disposed of, they do little 

 or no harm, but the germs of some 

 other lowly fungi may, on the con- 

 trary, be extremely mischievous ; the 

 microbes or bacteria that produce dis- 

 ease in man and domestic animals are 



product, such as I have previously 

 mentioned, they at once commence to 

 germinate and spread their hyphcr tlirough 

 the substance ; and so, in a few days, 

 another mould forest is produced, from 

 which millions of spores arise and are 

 wafted into tlie atmosphere. 



These fungi being parasitic on decay- 

 ing organic matter, naturally flourish 

 on such materials as jam, pickles, cheese, 

 bread, etc., for such materials are but 

 decaying substances. Whenever in our 

 methods of food preservation a weak 

 spot, due to souring or fermentation. 



