THE most extensive and successful culture of mushrooms in existence is carried on in widely-ramifying caves far beneath the surface in the vicinity of Paris. To give the reader as good an idea of it as I can we must visit one of the great “Mushroom caves” at Montrouge, just outside the fortifications of Paris, on the southern side. The surface of the ground is mostly cropped with wheat; but here and there lie, ready to be transported to Paris, blocks of white stone, which have recently been brought to the surface through coalpit-like openings. There is nothing like a “quarry,” as we understand it, to be seen; the stone is extracted as we extract coal, and with no interference whatever with the surface of the ground. We find a “champignonniste” after some trouble, and he accompanies us across some fields to the entrance of his subterranean garden. It is a circular opening like the mouth of an old well, but from it protrudes the head of a thick pole with sticks thrust through it. This pole, the base of which rests in darkness sixty feet below, is the easiest and indeed the only way by which human beings can get into the mine. I had an idea that one might enter sideways and in a more agreeable manner, but it was not so. Down the shaky pole my guide creeps, I follow, and soon reach the bottom, from which little passages radiate. A few little lamps fixed on pointed sticks are placed below, and, arming ourselves with one each, we slowly commence exploring dark, still, tortuous passages. I have heard that the first individual who commenced mushroom-growing in these catacomb-like burrowings was one who, at a particularly glorious epoch of the history of France, when a great many more brave garçons went to fight than returned from the victory, preferred, strange to say, to stay at home and hide himself rather than form a unit in “battle’s magnificently stern array.” Industrious and discreet youth! You deserve being held up as an example as much as the busy bee that improves each “shining hour.” [Illustration: Fig. 18. Mushroom-cave, 70 feet beneath the surface, at Montrouge, near Paris, July, 1868.] The passages are narrow, and occasionally we have to stoop. On each hand there are little narrow beds of half-decomposed stable manure running along the wall. These have been made quite recently, and have not yet been spawned. Presently we arrive at others in which the spawn has been placed, and is “taking” freely. The spawn in these caves is introduced into the little beds in flakes taken from an old bed, or, still better, from a heap of stable manure in which it occurs naturally. Such spawn is preferred, and considered much more valuable than that taken from old beds. Of spawn in the form of bricks, such as is used in England, there is none. [Illustration: Fig. 19. Newly-made bed against wall of cave.]