The trees, several hundred years old and with their branches meeting at a great height, formed an arch of foliage through which, here and there, shone a ray of sunlight. Their smooth trunks, with white bark, gave the effect of enormous columns sustaining the weight of an immense building full of shade and silence. On the lofty summits crows cawed while smoothing their feathers. Occasionally a redheaded green woodpecker, surprised at its work, which consists of pecking the wormy wood with its beak to make the insects come out that it feeds on, gave a cry of alarm and flew off like a dart. In the midst of the moss with which the ground was carpeted were here and there numbers of mushrooms. Some were round, smooth, and white. Jules could not admire them enough; he likened them in his imagination to eggs laid in a mossy hollow by some wandering hen. Others were glossy red, others bright fawn-color, and still others brilliant yellow. Some, just coming out of the ground, were enveloped in a kind of bag that tears open as the mushroom grows; some, more advanced, spread out like an open umbrella. Finally, there were many that had already begun to decay. In their fetid rottenness swarmed innumerable grubs, which later would become insects. After picking a number of the principal kinds, the party sat down at the foot of a beech, on the soft moss-carpet, and Uncle Paul spoke thus:

“A mushroom is the blossom of a plant that lives under ground and is called by learned men mycelium. This subterranean plant is composed of white, slender, fragile threads, resembling in their entirety a large cobweb. If you pull up a mushroom carefully you will see at the base of its stalk, in the earth that clings to it, numerous white threads of the mycelium. Let us imagine a rosebush planted so as to leave nothing but the roses above ground. The buried bush will represent the subterranean mycelium; the roses, open to the air, will represent the blossoms of the mycelium, that is to say the mushrooms.”

“A rosebush,” objected Jules, “has stout branches covered with leaves; the mushroom-plant, according to what I see, has nothing of the sort. It is a kind of moldiness that branches out in the ground in white veins.”

“Those white veins, so delicate that one can hardly touch them without breaking them, form the subterranean plant, without leaves or roots. They lengthen little by little in the ground to a pretty good distance from the point of departure. Then, at a favorable moment, they produce little swellings which grow under ground, become mushrooms, and burst open their bed of earth to expand in the air. This structure explains to us why mushrooms grow in groups. Each group, with the mycelium that produces it, constitutes one and the same plant.”

“I have seen groups of mushrooms in a perfect circle,” Claire remarked.

“If the ground is of uniform character and nowhere hinders the propagation of the subterranean vegetable in one direction rather than in another, the mycelium spreads equally on all sides, and so produces circular groups of mushrooms, which the country people sometimes call witches’ circles.”

“Why witches’ circles?” asked Jules.

“The ignorant and superstitious think they see an effect of witchcraft in this curious circular arrangement, whereas it is but the natural result of the uniformly equal development of the subterranean plant.”

“Then there are no witches?” said Emile.

“No, my dear. There are rogues who abuse the credulity of others; there are simpletons disposed to listen to them; but no one has preternatural powers.”