"Let us change the subject, and talk about lilies and roses." - E. Buxton.
FROM time out of mind there has been a close companionship between the lily and the rose. They have bloomed together in all gardens of delight, from Mother Eve's, where the rose was "without thorn," to grandmamma's, where they lived with single pinks, and gillyflowers, prince's-feather, and love lies-bleeding, behind prim hedges of clipped box. They have been together in heraldry, where the Rose of England and the Lily of France were blazoned on the same Plantagenet shields and banners, together in mediaeval art, where they have bloomed side by side at the feet of the Virgin, and together in the love-poetry of all times and lands from the Hebrew "Song of Songs" to Tennyson's "Maud".
But botany breaks up this immemorial fellowship and puts them far asunder. It tells us, indeed, that they have nothing in common.
Each represents one of the two great classes, into which most flowering plants are divided. The lily's tribe is described by the ponderous term "Monocotyledons," and includes palms, rushes, sedges, grasses, the Calla-lily and her kin, the queenly orchids, and many simple flowers, better known and better loved than either.
The rose is a "Dicotyledon," and member of a series whose names are legion.
The differences between these two great classes of plants, of which lily and rose are types, begin while they yet lie dormant in the seed and may be clearly seen at every point in their subsequent development.
Every seed, of whatever variety, contains a little plant, completely formed and snugly folded into the smallest possible compass. Packed around this little plant, or incorporated into its substance, there is (in most cases) a store of starchy food which will nourish it till it grows large and strong enough to shift for itself. And wrapped about the outside of the seed there are generally two coats, the inner very thin and fine, and the outer comparatively firm and tough.
The peculiarities which distinguish the seeds of the Monocotyledons may be readily seen in a grain of Indian corn which has been soaked in water till it is swollen and softened. If now we split it down lengthwise with a sharp penknife we can see something of its inner economy, without the aid of a microscope. Near the smaller end of the grain, and at one side, is a pale, tiny corn-plant. It has one leaf rolled into a hollow cone, and enclosing a little bud, whence other leaves would have developed had the plants sprouted in the ground. There is a short, thick stalk, and, at its base, a blunt point.
At this point lies a little group of cells, full of vital power, whence the roots of the seedling should have sprung.
But the whole young plant or germ occupies but a small proportion of the seed's interior, and all the rest of the space is filled with stored food for the seedling's first growth.
The wheat germ lies in a similar position to that of the baby corn-plant, in the narrower end of the seed, and pressed against its wall. And in it, as in all the grains and grasses, Nature has provided very liberally for the first needs of the sprouting plant. This is the reason why the seeds of grasses - corn, wheat, rye, barley, rice, and oats - are among the chief food products of the world.
In all these seeds the store of nourishment is packed around the little plant, close to it, but distinct from it.
Scientific botanists call such seeds as this "albuminous," and they are produced by the majority of the lily's kin.
The seeds of most dicotyledons, on the contrary, contain little or nothing, except the baby-plant, and are called "exalbuminous".
But we must not infer from this term that the kin of the rose send their offspring out portionless into the cold world. Food for the seedling during its feeble infancy is generally present, and often abundant. Peas, beans, and acorns are fat and firm with starches for the young plant. Rape, flaxseed, and castor-oil beans are rich in vegetable oil, and nearly all seeds contain nitrogenous nourishment in the form of aleurone.
But this nourishment is stored, not around the baby-plant, but within the tissues of the first leaves. And these leaves, in the kin of the rose, are always two in number. Their substance has formed part of the seed, and therefore they are called seed-leaves or "cotyledons," and all the plants which have two of them are distinguished as dicotyledons (two-seed leaves). When we take the woody shell off an acorn, or strip the skin from a bean, we find that the white substance which remains splits naturally into halves. These are the two first leaves of the young plant, so distended by the nourishment stored within them that their true character is not at once discernible. Folded between them lie two more leaves, almost white and very tiny, which will be unfolded to the light as soon as the young plant gets its head fairly above ground, and between these inner and younger leaves is that portion of the plant which will carry on the work of development - the growing point.
Sometimes, when the cotyledons are very large and heavy, the tender stem of the seedling seems unequal to the task of lifting them above ground. This is the case with germinating acorns and horse-chestnuts.
The nut remains beneath the ground or on its surface, and the first leaves which the seedling-oak or horse-chestnut unfolds to the light correspond to the first pair of soft, green leaves which appear on the little bean-plant.
The halves of the sprouting bean, which appear above ground as two thick, oval seed-leaves, correspond to the halves of the sprouting horse-chestnut, which lie half buried beneath the soil.
After the dicotyledon has formed its roots and is fairly started in life, its leaves may grow up the stem singly or in pairs, and new ones may unfold one at a time or two together. But whatever individual eccentricities or family characteristics appear in the arrangement of later foliage, the seed-leaves of the rose's kin are always two, alike and opposite.