The plants of this group agree in their general structure with the adder's-tongue, which is a thoroughly typical representative of the group; but nevertheless, there is much variation among them in the details of structure. While most of them are herbaceous forms (dying down to the ground each year), a few, among which may be mentioned the yuccas ("bear grass," "Spanish bayonet") of our southern states, develop a creeping or upright woody stem, increasing in size from year to year. The herbaceous forms send up their stems yearly from underground bulbs, tubers, _e.g._ _Trillium_ (Fig. 83, _A_), or thickened, creeping stems, or root stocks (rhizomes). Good examples of the last are the Solomon's-seal (Fig. 83, _B_), _Medeola_ (_C_, _D_), and iris (Fig. 84 _A_). One family, the yams (_Dioscoreæ_), of which we have one common native species, the wild yam (_Dioscorea villosa_), have broad, netted-veined leaves and are twining plants, while another somewhat similar family (_Smilaceæ_) climb by means of tendrils at the bases of the leaves. Of the latter the "cat-brier" or "green-brier" is a familiar representative. [Illustration: FIG. 83.--Types of _Liliifloræ_. _A_, _Trillium_, × ¼. _B_, single flower of Solomon's-seal (_Polygonatum_), × 1. _C_, upper part of a plant. _D_, underground stem (rhizome) of Indian cucumber root (_Medeola_), × ½. _E_, a rush (_Juncus_), × 1. _F_, a single flower, × 2. _A-D_, _Liliaceæ_; _E_, _Juncaceæ_.] The flowers are for the most part conspicuous, and in plan like that of the adder's-tongue; but some, like the rushes (Fig. 83, _E_), have small, inconspicuous flowers; and others, like the yams and smilaxes, have flowers of two kinds, male and female. [Illustration: FIG. 84.--Types of _Liliifloræ_. _A_, flower of the common blue-flag (_Iris_), × ½ (_Iridaceæ_). _B_, the petal-like upper part of the pistil, seen from below, and showing a stamen (_an._). _st._ the stigma, × ½. _C_, the young fruit, × ½. _D_, section of the same, × 1. _E_, diagram of the flower. _F_, part of a plant of the so-called "gray moss" (_Tillandsia_), × ½ (_Bromeliaceæ_). _G_, a single flower, × 2. _H_, a seed, showing the fine hairs attached to it, × 1. _I_, plant of pickerel-weed (_Pontederia_), × ¼ (_Pontederiaceæ_). _J_, a single flower, × 1. _K_, section of the ovary, × 4.]