2 4 d ODD HOURS WITH NATURE 



development is just an extension of the process. 

 The mycelium exhausts the ground which it 

 occupies, and therefore its further growth must 

 be outward. It follows that in its second stage 

 there is a small circular patch of exhausted ground 

 surrounded by an outward -growing circle of living 

 mycelius. This hi turn exhausts its grounds, 

 and continues to grow from its outside edge 

 into the unexhausted soil without. The circle of 

 growing mushrooms and the circle of withered 

 grass are therefore explained, and all that remains 

 to account for is the verdure within. And this is 

 explained by the fact that the out ward -growing 

 mycelium, developing from its outside edge, must 

 always leave behind it a mass of mushroom sub- 

 stance, which, since it has nothing to live on, dies 

 and decays. Thus the mushroom, which begins by 

 impoverishing the ground it occupies, ends by 

 enriching it with a manure opulent in the most 

 valuable nitrogenous properties. 



It will be seen from this that the fairy ring is 

 a growth it may be a growth of many years' 

 endurance ; and sometimes the green circle 

 becomes so extensive that, if placed on a hillside, 

 it may be picked out at a great distance. But 

 the circular form is not always observed. Some- 

 times, as has been said, two growing circles meet, 

 and as they cannot extend into the ground ex- 

 hausted of mushroom food by each other, they 

 coalesce and form a figure eight. Where the 

 ground is particularly favourable many rings may 

 thus meet and produce an outline of undulating 

 curves. Again, a growing ring may meet an 



