M. Gasparin, in his report on the production of truffles, made to the great "Paris Exposition" of 1855, refers to the "natural truffle-grounds at Vaucluse," where the "common oak produces truffles like the evergreen oak;" although, in other localities, owing no doubt to the different conditions of the soil, those gathered at the base of the one species of oak differ very materially from those gathered at the base of the other. All these experimental results, and many others we might give in connection with the culture of edible fungi, point to the conditions of the soil, produced by natural rather than artificial means, as all-essential for the propagation of fungus spores, as well as their development into full-sized plants. The cultivation of other and minuter fungi, for scientific purposes, need not be referred to in this connection. The same general observations will be found to apply in the case of all the experiments tried, although some very curious and remarkable modifications occur where pseudospores are to be found in the micelium of different plants. Nearly all these fungi have their own parasites, originating undoubtedly in the diseased conditions of the plant from which they derive their nutriment. Indeed, all fungi, whether parasitic or non-parasitic, have their origin, more or less definitely occurring, in decay. It is no more true that death is a necessity of life, than that life is an equal necessity of death. As out of the dead past springs the eternally living present, so from the "muddy vesture of decay" spring all the marvellous powers of reproduction with which nature was endowed from the beginning.