190 



ABOUT FUNGI. 



[CHAP. 



carted down King William Street, and a year or 

 so ago an undescribed Peziza flourished inside my 

 cistern." 



Besides the pleasure of healthy association with 

 beautiful scenery obtained in searching for them, 

 fungi have a claim upon our at- 

 tention for other reasons. First, 

 they are by no means insignifi- 

 cant factors in the economy of 

 Nature. As we have said, they 

 are parasites and scavengers. 

 Much of the natural food of man 

 is destroyed by these plants, and 

 for this reason alone we ought 

 to know something about them. 

 One of the most troublesome 

 fungi in this respect is Peronospora infestans, the 

 Potato fungus, to which we have referred at some 



FIG. 142. 



FIG. 143. 



length in Chapter I. As will be seen, on reference 

 to fig. 142, it is one of the moulds, somewhat resem- 

 bling Mucor. Fig. 143 shows a section of the potato 



