YUCCA, ADAM'S NEEDLE; a genus of the monogynia order belonging to the hexandria class of plants.
Species. 1. The gloriosa, or common Adam's needle; rises with an erect, ligneous, thick stem two or three feet high, having very long, narrow, stiff, entire leaves ending in a long, sharp, black-spine, garnishing the stem almost to the bottom and in a large tuft at top; and from the centre of the top leaves rises a long branching peduncle, sustaining a panicle of bell-shaped white and purple flowers.
2. The filamentosa, or Virginia yucca; rises with an upright, thick, ligneous stem two or three feet high, adorned at top with a tuft of very long, spear-shaped, stiff, blunt-pointed, sawed filamentose leaves, emitting long threads from the sides, hanging downward; and from the top of the stem amidst the leaves an erect peduncle or flower-stalk, several feet high, garnished with many large, white, and purple-striped leaves. Both these species flower in August and September, and make an ornamental appearance, but are not succeeded by seeds in this country. They are natives of North America, the former that of Canada, and the latter of Virginia, and are both tolerably hardy.
3. The aloifolia, or aloe-leaved yucca; rises with an erect, thick, fleshy stem, eight or ten feet high, crowned with a large tuft of long narrow, stiff, crenated, aloe-like leaves, ending in sharp spines; and from the centre of the crown of leaves come out the flower-stalk, branching pyramidally two or three feet high, having all the branches terminating in a spike of flowers, purple without and white within, appearing in August and September.
4. Draconis, or tree-leaved yucca; rises with an upright, thick, brown stem, three feet high, crowned with long, narrow, serrated leaves ending in spines and nod downward; and in the centre of the leaves arise the flower-stalk very branchy, with all the branches terminating in spikes of flesh-coloured flowers in August and September.
All these four species of yucca, being of singularly curious growth, are worthy of culture in every good collection, keeping some of all the sorts in pots, to move to shelter of a green-house in winter, as they will afford a conspicuous and entertaining variety in this collection: some plants of the two first sorts may also, after attaining a little strength and gradually hardened, be planted out in the full ground in some dry warm situation, sheltered by adjacent shrubs and trees. As all the sorts are of a succulent nature, they should always be planted in a light dry soil; if somewhat sandy the better. The propagation of all the sorts is by off-sets and suckers, from the root and head of the plants; also by seed. The two last kinds being tender, cannot bear the open air.
Uses. A kind of bread is made from the roots of this plant by the Indians, which much resembles that from the Cassava. See Jatropha.
Z, or z, the twenty-fourth and last letter, and the nineteenth consonant of our alphabet; the sound of which is formed by a motion of the tongue from the palate downwards and upwards to it again, with a shutting and opening of the teeth at the same time. This letter has been reputed a double consonant, having the sound ds; but some think with very little reason; and, as if we thought otherwise, we often double it, as in puzzle, muzzle, &c. Among the ancients, Z was a numeral letter, signifying two thousand, and with a dash added a-top, Z̄ signified two thousand times two thousand, or four millions.
In abbreviations this letter formerly stood as a mark for several sorts of weights; sometimes it signified an ounce and a half, and very frequently it stood for half an ounce; sometimes for the eighth part of an ounce, or a dram Troy weight; and it has in earlier times been used to express the third part of an ounce, or eight scruples. ZZ were used by some of the ancient physicians to express myrrh, and at present they are often used to signify zinziber, or ginger.