The Yam (Dioscoreæ), and the Elephant’s-foot (Testudinaria), are the principal genera in this order; and both have an enormously-large tuberous root which is eatable, and a very slender climbing stem, with rather small leaves and inconspicuous flowers. The ovary is below the flower, and the fruit is capsular.
ORDER CXCIII.—TAMACEÆ.
This order consists only of the genus Tamus, the Black Bryony, which Dr. Lindley includes in Dioscoreæ. It has, however, a berry-like fruit.
ORDER CXCIV.—SMILACEÆ.
This order includes Smilax, the root of a species of which affords the drug called Sarsaparilla, the Lily of the Valley (Convallaria), and the Alexandrian Laurel, or Butcher’s Broom (Ruscus). The male and female flowers in Smilax are on different plants; and in Ruscus the flowers spring from the middle of the leaves. The perianth is in six equal segments, and there are six stamens. The ovary is three-celled, with the cells one or many seeded, and the fruit is a globose berry. The seeds, when ripe, have a brown membranous skin. Dr. Lindley confines this tribe to Smilax, and Ripogonum; and includes the other genera in Liliaceæ.
ORDER CXCV.—ASPHODELEÆ.