_Inarching_ bears considerable resemblance to layering, as it is performed without separating the part which is to form the new plant. A branch is bent from a living plant, and partly cut through, and, the tongue thus formed being introduced into a slit made in another plant, the two are bound closely together. It is obvious that this mode of grafting, which is called inarching, can only be practised with plants in pots, as it requires the two plants that are to be united to be brought close together, and to remain so till the graft has taken effect. You must observe that, in all kinds of grafting and budding, there must be a considerable degree of resemblance between the scion and the stock, for the graft to take effect. Thus, though one stoned fruit may be grafted on another, such as the almond or peach on the plum, a stoned fruit cannot be grafted on a kerneled fruit, such as a plum on an apple or a pear. In the like manner, an apple cannot be grafted on an orange, which was formerly supposed to be done, to produce a pomegranate; nor a rose on a black currant, which it was formerly believed would produce a black rose. It is true that plants are sometimes sold in Italy which appear to have been unnaturally grafted, such as a rose upon an orange; but it will be found, when closely examined, that the pith of the orange has been artfully scooped out, and the stem of the rose tree introduced into the hollow space thus formed, through a hole made in the stem close to the root. In this way the two plants may appear to be one for some time; as the stem of the orange tree will live and produce leaves two or three years after the pith is removed, provided the operation has been performed carefully.