1, One of the gills or lamellæ of the mushroom slightly magnified, showing the cells round the edge. c, Cells which do not bear spores. fc, Fertile cells. 2, A piece of the edge of the same powerfully magnified, showing how the spores s grow out of the tip of the fertile cells fc.
"First, under a moderate power, you will see the cells forming the centre of the fold and the layer of long cells (c and fc) which are closely packed all round the edge. Some of these cells project beyond the others, and it is they which bear the spores. We see this plainly under a very strong power when you can distinguish the sterile cells c and the fertile cells fc projecting beyond them, and each bearing four spore-cells s on four little horns at its tip.
"These spores fall off very easily, and you can make a pretty experiment by cutting off a large mushroom head in the early morning and putting it flat upon a piece of paper. In a few hours, if you lift it very carefully, you will find a number of dark lines on the paper, radiating from a centre like the spokes of a wheel, each line being composed of the spores which have fallen from a fold as it grew ripe. They are so minute that many thousands would be required to make up the size of the head of an ordinary pin, yet if you gather the spores of the several kinds of mushroom, and examine them under a strong microscope, you will find that even these specks of matter assume different shapes in the various species.
"You will be astonished too at the immense number of spores contained in a single mushroom head, for they are reckoned by millions; and when we remember that each one of these is the starting point of a new plant, it reminds us forcibly of the wholesale destruction of spores and seeds which must go on in nature, otherwise the mushrooms and their companions would soon cover every inch of the whole world.
"As it is, they are spread abroad by the wind, and wherever they escape destruction they lie waiting in every nook and corner till, after the hot summer, showers of rain hasten the decay of plants and leaves, and then the mushrooms, toadstools, and puffballs, grow at an astounding pace. If you go into the woods at this season you may see the enormous deep-red liver fungus (Fistulina hepatica) growing on the oak-trees, in patches which weigh from twenty to thirty pounds; or the glorious orange-coloured fungus (Tremella mesenterica) growing on bare sticks or stumps of furze; or among dead leaves you may easily chance on the little caps of the crimson, scarlet, snowy white, or orange-coloured fungi which grow in almost every wood. From white to yellow, yellow to red, red to crimson and purple black, there is hardly any colour you may not find among this gaily-decked tribe; and who can wonder that the small bright-coloured caps have been supposed to cover tiny imps or elves, who used the large mushrooms to serve for their stools and tables?
"There they work, thrusting their tubes into twigs and dead branches, rotting trunks and decaying leaves, breaking up the hard wood and tough fibres, and building them up into delicate cells, which by and by die and leave their remains as food for the early growing plants in the spring. So we see that in their way the mushrooms and toadstools are good imps after all, for the tender shoot of a young seedling plant could take no food out of a hard tree-trunk, but it finds the work done for it by the fungus, the rich nourishment being spread around its young roots ready to be imbibed.
"To find our fairy-ring mushrooms, however, we must leave the wood and go out into the open country, especially on the downs and moors and rough meadows, where the land is poor and the grass coarse and spare. There grow the nourishing kinds, most of which we can eat, and among these is the delicate little champignon or 'Scotch-bonnet' mushroom, Marasmius Oreades,[1] which makes the fairy-rings. When a spore of this mushroom begins to grow, it sucks up vegetable food out of the earth and spreads its tubes underground, in all directions from the centre, so that the mycelium forms a round patch like a thick underground circular cobweb. In the summer and autumn, when the weather is suitable, it sends up its delicate pale-brown caps, which we may gather and eat without stopping the growth of the plant.
"This goes on year after year underground, new tubes always travelling outwards till the circle widens and widens like the rings of water on a pond, only that it spreads very slowly, making a new ring each year, which is often composed of a mass of tubes as much as a foot thick in the ground, and the tender tubes in the centre die away as the new ones form a larger hoop outside.
"But all this is below ground; where then are our fairy rings? Here is the secret. The tubes, as we have seen, take up food from the earth and build it up into delicate cells, which decay very soon, and as they die make a rich manure at the roots of the grass. So each season the cells of last year's ring make a rich feeding-ground for the young grass, which springs up fresh and green in a fairy ring, while outside this emerald circle the mushroom tubes are still growing and increasing underneath the grass, so that next year, when the present ring is no longer richly fed, and has become faded and brown like the rest of the moor, another ring will spring up outside it, feeding on the prepared food below."
"In bad seasons, though the tubes go on spreading and growing below, the mushroom fruit does not always appear above ground. The plant will only fruit freely when the ground has been well warmed by the summer sun, followed by damp weather to moisten it. This gives us a rich crop of mushrooms all over the country, and it is then you can best see the ring of fairy mushrooms circling outside the green hoop of fresh grass. In any case the early morning is the time to find them; it is only in very sheltered spots that they sometimes last through the day, or come up towards evening, as I found them last night on the warm damp side of the dell.