244 



it iouad a faTourable state of the soil and the requisite materitth of growth, 

 and that both these conditions were provided by the moles, which usually made 

 their spring wanderings in runs of a more or less circular form. This may be 

 termed the "mole theory" of their formation. He was not going to discus* 

 these theories or any other, for there were several, but he mentioned them 

 because he wished to suggest a few experiments of a very simple nature to 

 such of the members as lived in the country, and had leisure to carry them out. 



Directly they observe the rings of the common "Fairy ring fungus" 

 (Marasmius OreadenJ springing up, first let them cut a square foot of turf and 

 soil out a few yards from the ring, loosen the soil, and add if they please a very 

 little rotten manure, then cut a piece of the same size, including a portion of 

 the ring, and remove it as carefully as possible to the prepared hole ; in short, 

 making an exchange. 



2ndly. When the ring is large— a ring of the horse mushrocm (Agaricus 

 arvensis) is particularly favourable for this experiment — let them cut a straight 

 trench at right angles to the ring, say a yard long within the cucle up to the 

 ring, and a yard long without from it, raise the turf and loosen the soil to a 

 depth of 8 or 10 inches, add a little manure all along it, and then restore the 

 turf. By this experiment the ring need not be disturbed, nor the mycelium 

 injured. 



Srdly. A carefully cut, and still more carefully carried, portion of a ring 

 might be inserted into the middle of a mushroom bed purposely made, or of a 

 used-up cucumber bed, where the soil was loose, and the material of growth 

 Abundant in all directions. 



Other modes of varying these experiments would suggest themselves to 

 any one who thinks over the subject. They would require great nicety in 

 carrying out, so as to be deep enough to get the mycelium, and to move it with 

 as little injury as possible. No doubt many of these experiments would fail, 

 and be therefore simply negative, but if any one of them succeeded, it could 

 not fail to be of great interest. He did not believe common observation of the 

 rings themselves would give the solution, or it would have been discovered ere 

 this. 



The President supported Dr. Bull in urging the members to interest 

 themselves in this subject, and to make the experiments ; but he thought, 

 however, that a good deal might still be learnt by careful observation of the 

 growth of the rings from year to year, marking the size of the rings accurately 

 by fixing pegs into the ground and leaving them for the following year. He 

 was quite sure, if they would take the trouble to make the experiments and 

 observations suggested, that they would become interested in it, and could not 

 fail to gain some useful information. 



Dr. Bull said : Gentlemen fond of gathering mushrooms in their own 

 fields might like to know that a dressing of common salt on the grass in 

 spring was the best manure to encourage their growth, and it was also equally 

 good for the pasture itself. 



