But the case is evidently different with plants. They are intended fixedly to occupy many places comparatively unfit for them, and to fill up all the spaces where greenness, and coolness, and ornament, and oxygen are wanted, and that with very little reference to their comfort or convenience. Now it would be hard upon the plant if, after being tied to a particular spot, where it is indeed much wanted, and is a great blessing, but where it has enough to do to live, whence it cannot move to obtain what it wants or likes, but must stretch its unfortunate arms here and there for bare breath and light, and split its way among rocks, and grope for sustenance in unkindly soil; it would be hard upon the plant, I say, if under all these disadvantages, it were made answerable for its appearance, and found fault with because it was not a fine plant of the kind. And so we find it ordained that in order that no unkind comparisons may be drawn between one and another, there are not appointed to plants the fixed number, position, and proportion of members which are ordained in animals, (and any variation from which in these is unpardonable,) but a continually varying number and position, even among the more freely growing examples, admitting therefore all kinds of license to those which have enemies to contend with, and that without in any way detracting from their dignity and perfection. So then there is in trees no perfect form which can be fixed upon or reasoned out as ideal; but that is always an ideal oak which, however poverty-stricken, or hunger-pinched, or tempest-tortured, is yet seen to have done, under its appointed circumstances, all that could be expected of oak. The ideal, therefore, of the park oak is that to which I alluded in the conclusion of the former part of this work, full size, united terminal curve, equal and symmetrical range of branches on each side. The ideal of the mountain oak may be anything, twisting, and leaning, and shattered, and rock-encumbered, so only that amidst all its misfortunes, it maintain the dignity of oak; and, indeed, I look upon this kind of tree as more ideal than the other, in so far as by its efforts and struggles, more of its nature, enduring power, patience in waiting for, and ingenuity in obtaining what it wants, is brought out, and so more of the essence of oak exhibited, than under more fortunate conditions. Sec. 10. Ideal form in vegetables destroyed by cultivation.