“From the bulblet to the bulb, from garlic to an onion, there is but a single step. Let us split an onion in two from top to bottom. We shall find it composed of a succession of fleshy scales compactly fitted together. In the heart of this cluster of succulent scales, which are nothing but leaves so modified as to form a food-storehouse, are found other leaves of normal shape and green color. An onion, then, is a bud provisioned for an independent life by the conversion of its outside leaves into fleshy scales; and it is called a bulb, not a bulblet, because of its size, the latter term being the diminutive form of ‘bulb.’ Bulb and bulblet differ merely in size: the bulb is larger, the bulblet smaller, and that is all. “Every one has noticed that an onion hanging on the wall ready at hand for the cook, is awakened to life in the course of the winter by the heat of the room, and from within its envelope of red scales puts forth a beautiful green shoot that seems to protest against the rigors of the season and reminds us of the sweet pleasures of spring. As it develops, its fleshy scales wrinkle, soften, become flabby, and finally fall off in decay to serve as fertilizer for the young plant. Sooner or later, however, its store of provision being exhausted, the shoot perishes unless placed in earth. There we have a striking example of a bud that develops independently by means of its own accumulated supplies. The leek is also a bulb, but very slender in shape. Like the onion, it consists of a cluster of lower leaf-parts sheathed one inside another. Among ornamental plants having bulbs are the lily, the tulip, and the hyacinth.” CHAPTER XIX TUBERS—STARCH “There are buds that, though called to an independent existence, do not, before separating from the mother plant, store up provisions nor thicken their scales; but the plant itself is charged with feeding them. When it is intended that the stem or branch shall itself maintain the buds it bears, then, instead of coming out into the open air where it would speedily cover itself with foliage and flowers, it remains underground and has for leaves only rudimentary scales. It grows so corpulent and deformed as to cease to bear the name of branch and to take instead that of tuber. As soon as necessary supplies have been stored up, the tuber detaches itself from the mother plant, and thenceforth the buds it bears find in it abundant nourishment for their separate existence. A tuber, then, is an underground branch swollen with nutritive material and having undeveloped scales in place of leaves, and it is also dotted here and there with buds which it must feed.