Much more conspicuous are these general and special relations of form to general and special actions in the environment, among phænogams that are multiaxial. That when standing alone, and in places where the winds do not injure them nor adjacent things shade them, shrubs and trees develop with tolerable evenness on all sides, is an obvious truth. Equally obvious is the truth that, when growing together in a wood, and mutually interfered with on all sides, trees still show obscurely radial distributions of parts; though, under such conditions, they have tall taper stems with branches directed upwards--a difference of shape clearly due to the different incidence of forces. And almost equally obvious is the truth, that a tree of this same kind growing at the edge of the wood, has its outer branches well developed and its inner branches comparatively ill-developed. Fig. 197, which inaccurately represents this difference, will serve to make it manifest that while one of the peripheral trees can be cut into something like two similar halves by a vertical plane directed towards the centre of the wood--a plane on each side of which the conditions are alike--it cannot be cut into similar halves by any other plane. A like divergence from an indefinitely-radial symmetry towards an indefinitely-bilateral symmetry, occurs in trees that have their conditions made bilateral by growing on inclined surfaces. Two of the common forms observable in such cases are given in Fig. 198. Here there is divisibility into parts that are tolerably similar, by a vertical plane running directly down the hill; but not by any other plane. Then, further, there is the bilateralness, similar in general meaning though differently caused, often seen in trees exposed to strong prevailing winds. Almost every sea-coast has abundant examples of stunted trees which, like the one shown in Fig. 199, have been made to deviate from their ordinary equal growth on all sides of a vertical axis, to a growth that is equal only on the opposite sides of a vertical plane directed towards the wind’s eye. From among vegetal aggregates of the third order, we have now only to add examples of the entirely asymmetrical form which accompanies an entirely irregular distribution of incident forces. Creeping plants furnish such examples. They show, both when climbing up vertical or inclined surfaces and when trailing on the ground, that their branches grow hither and thither as the balance of forces aids or opposes; and the general outline is without symmetry of any kind, because the environing influences have no kind of regularity in their arrangement.