YUCCA FILAMENTOSA.--Silk Grass. North America, 1675. A well-known and beautiful plant, with numerous leaves arranged in a dense rosette, and from 1 foot to 2 feet long by 2 inches broad. Flower scape rising to 5 feet or 6 feet in height, and bearing numerous flowers that are each about 2 inches deep. There is a beautiful variegated form of this species named Y. filamentosa variegata, and one with much narrower leaves than the typical species, and known as Y. filamentosa angustifolia.
Y. GLORIOSA.--The Mound Lily. United States, 1596. This is another well-known hardy species, with long, sharp-pointed leaves, and a handsome, much branched scape, of flowers that are each about 2 inches deep. There are several varieties, differing in colour of foliage, including Y. gloriosa glaucescens, with decidedly glaucous foliage; Y. gloriosa superba, with rigid leaves and a shorter and denser flower scape; and another with variegated leaves. Y. gloriosa recurvifolia is usually dwarfer in the stem than the type, and more inclined to branch than the other species, and less rigid, with recurving leaves that are not so sharp-pointed, The flower panicle is large and very much branched.
The Yuccas all do well if planted in light loam of good quality.
ZELKOVA ACUMINATA (_syns Z. japonica_ and _Planera acuminata_).--Japan. This resembles very nearly our common Elm in appearance, and being perfectly hardy is to be recommended for planting in this country.
Z. CRENATA (_syns Planera crenata_ and _P. Richardi_).--Zelkova Tree. Western Asia to Mount Caucasus, 1760. This is a handsome, large growing tree, with oblong deeply-crenated leaves, and small and inconspicuous flowers. For avenue planting or as a standard specimen this is a valuable tree, being quite hardy, and of free and quick growth. P. crenata pendula is a good weeping form, and worthy of culture.
Z. CRETICA.--Crete. A pretty small growing bush or tree of about 20 feet in height, with crenate, leathery, dark green leaves, which are usually fully an inch in length. The leaves are hairy, and the twigs, too, are thickly covered with short grey hairs.
ZAUSCHNERIA CALIFORNICA.--Californian Fuchsia, or Humming Birds' Trumpet. California and Mexico, 1847. A small-growing, densely-branched shrub, with linear-lanceolate silvery pubescent leaves, and bright red or scarlet tubular flowers, with a long, slender style resembling some of the Fuchsias. It is a pretty and distinct Alpine shrub, and not being perfectly hardy should be assigned a rather warm and sheltered position.