Mushrooms and Other Spore Plants 



duced by a wide variety of specific agents, fungi, bacteria, 

 worms, insects, weather, soil conditions, etc. Of these various 

 causes, the fungi are among the most conspicuous, widely dis- 

 tributed, and diversified. There are vast numbers of disease- 

 producing fungi. The life-cycles of many of these are not yet 

 completely known. Three important stages, however, may be 

 recognized in the life cycle of any fungus, the plant body 

 (a mass of parisitic threads penetrating and feeding upon the 

 tissues of the host) ; the " fruiting" or spore-producing part 

 (ex. bracket fungus) ; and third, the incredibly abundant micro- 

 scopic spores. The spores are carried great distances by the 

 wind, and can long resist unfavorable conditions. These fea- 

 tures have much to do with the universal distribution and 

 abundance of the fungus diseases. 



" A conservative estimate of the damage caused by fungi 

 attacking corn, wheat, oats, barley and rye is said to be $200,- 

 000,000 annually; and this amount is stolen so steadily that 

 few realize their loss." Hodge. 



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