372. The flower as the standard of beauty. So it has ever been regarded. Through this attribute, so evidently divine in its origin, it breathes on the heart an influence which is essentially spiritual, always pleasing, elevating, and pure. The benevolent Thought which first conceived of this crowning glory of the vegetable world had evidently in view the education of man's moral nature as well as the reproduction and permanence of vegetable nature.
373. The flower in the light of science. The pleasure of the florist in contemplating the flower as merely an object of taste is not diminished when he comes to view it in the light of science. Parts which he before regarded as embellishments only, now assume new value as indispensable agents in fulfilling a great design; every organ takes form according to the sphere of its office, and the beau-ful flower no longer appears as the possible accident of a chance-world.
374. Its nature and origin. Wo have before observed that the flower-bud is, in nature and origin, one and the same with the leaf-bud. Now a leaf-bud is regularly unfolded into a leafy branch. A flower-bud is unfolded into a flower. Hence the flower, in its nature and origin, is one and the same with a leafy branch.
375. Theoretical view. When, therefore, this new necessity arises in the life of a plant, viz., the perpetuation of its species, no new principle or organ is evoked, but the leaf, that same protean form which we have already detected in shapes so numerous and diverse, the leaf, is yet once more in nature's hand molded into a series of forms of superior elegance, touched with colors more brilliant, and adapted to a higher sphere as the organs of reproduction.
376. The evidence on which this theory rests may be referred to two sources; namely, natural and artificial development. We mention a few instances of each kind, earnestly recommending the student to study for himself the many facts which will fall under his own observation bearing upon this deeply interesting theory.
377. Case of the poppy. The ordinary complete flower, e. g., the poppy, consists of four kinds or sets of organs, viz., the sepals (outside), petals next, stamens and pistils, and each kind is quite different and distinct from the others. The metamorphosis of the leaf, first into the sepal then the petal, etc., is so abrupt that it seems to lose its identity at once. But there are some
378. Cases in the natural development of plants where the transition of the leaf is gradual, changing insensibly, first to bracts then to sepals, thus apparently making the metamorphosis in question visible before our eyes. Such cases are exactly in point. The leaves of the paeony, large and much divided below, become smaller and more simple above, gradually passing into bracts and thence into sepals. In Calycanthus the sepal passes into the petal by gradations so gentle that we can not mark the limit between them. In the lilies these two organs are almost identical. In the water-lily, where the sepal, petal, and stamen are all thus graduated, the transition from petal to stamen is particularly instructive. These two forms meet half way by a perfect series of gradations, when a narrowed petal is capped slightly with the semblance of an anther. And finally, cases of a close resemblance between stamen and pistil, so unlike in the poppy, are not wanting, as in the tulip-tree.
229, Papaver (poppy); 8, stamens; p, stigmas. 230, Sepal. 231, Petal - all very different. 282 Petals of the water-lily (Nyniphaea) gradually passing into (240) stamens.
379. Flowers always regular in the early bud. An early examination of flower-buds often exhibits the several kinds of organs much less diverse than they subsequently become. See the early bud of columbine. Those flowers which are called irregular, as the pea, catmint, violet, are regular, like other flowers, in the early bud; that is, the several petals are at first seen to be precisely similar, becoming dissimilar and distorted in their after growth; so in the stamens and other or gans.
241, Ranunculus acris; a single flower. 242, R. acris, β. plena, a double flower. 243, Epacris lmpressa; the flowers changing to leafy branches (Lindley).
380. Cases in artificial development or teratology (τέpa, a monstrosity, λόγος), where organs of one kind are converted into those of another kind by cultivation, afford undeniable evidence of the doctrine in question - the homology of all the floral organs with the leaf. Such cases are frequent in the garden, and however much admired, they are monstrous, because unnatural. In all double flowers, as rose, paeony, Camillia, the stamens have been reconverted into petals, either wholly or partially, some yet remaining in every conceivable stage of the transition. In the double butter-cup (242) the pistils as well as stamens revert to petals, and in the garden cherry, flowering almond, a pair of green leaves occupy the place of the pistils. By still further changes all parts of the flower manifest their foliage affinities, and the entire flower-bud, after having given clear indications of its floral character, is at last developed into a leafy branch. (Fig. 243.)
381. In Clarkia, Celastrus, damask rose, and other garden plants, cases have been noted wherein the petal asserts its foliar nature by producing a secondary flower-bud in its axil 1 Thu3 in a thousand instances of abnormal growth, we find evidence proving the leaf to be the type whence all other forms of appendages are derived, and whither all tend to return.