The last family (_Solaneæ_) includes the nightshades (_Solanum_) (Fig. 119, _D_), to which genus the potato (_S. tuberosum_) and the egg-plant (_S. Melongena_) also belong. Many of the family contain a poisonous principle, _e.g._ the deadly nightshade (_Atropa_), tobacco (_Nicotiana_), stramonium (_Datura_), and others. Of the cultivated plants, besides those already mentioned, the tomato (_Lycopersicum_), and various species of _Petunia_ (Fig. 119, _H_), _Solanum_, and _Datura_ are the commonest. The second order of the _Anisocarpæ_ consists of plants whose flowers usually exhibit very marked, bilateral symmetry (_Zygomorphism_). From the flower often being two-lipped (see Fig. 120), the name of the order (_Labiatifloræ_) is derived. Of the nine families constituting the order, all but one are represented within our limits, but the great majority belong to two families, the mints (_Labiatæ_) and the figworts (_Scrophularineæ_). The mints are very common and easily recognizable on account of their square stems, opposite leaves, strongly bilabiate flowers, and the ovary splitting into four seed-like fruits (Fig. 120, _D_, _F_). The great majority of them, too, have the surface covered with glandular hairs secreting a strong-scented volatile oil, giving the peculiar odor to these plants. The dead nettle (_Lamium_) (Fig. 120, _A_) is a thoroughly typical example. The sage, mints, catnip, thyme, lavender, etc., will recall the peculiarities of the family. The stamens are usually four in number through the abortion of one of them, but sometimes only two perfect stamens are present. [Illustration: FIG. 120.--_Anisocarpous sympetalæ_ (_Labiatifloræ_). _A_, dead nettle, _Lamium_, (_Labiatæ_), × ½. _B_, a single flower, × 1. _C_, the stamens and pistil, × 1. _D_, cross-section of the ovary, × 2. _E_, diagram of the flower; the position of the absent stamen is indicated by the small circle. _F_, fruit of the common sage, _Salvia_ (_Labiatæ_), × 1. Part of the persistent calyx has been removed to show the four seed-like fruits, or nutlets. _G_, section of a nutlet, × 3. The embryo fills the seed completely. _H_, part of an inflorescence of figwort, _Scrophularia_ (_Scrophularineæ_), × 1. _I_, cross-section of the young fruit, × 2. _J_, flower of speedwell, _Veronica_ (_Scrophularineæ_), × 2. _K_, fruit of _Veronica_, × 2. _L_, cross-section of _K_. _M_, flower of moth-mullein, _Verbascum_ (_Scrophularineæ_), × ½. _N_, flower of toad-flax, _Linaria_ (_Scrophularineæ_), × 1. _O_, leaf of bladder-weed, _Utricularia_ (_Lentibulariaceæ_), × 1. _x_, one of the "traps." _P_, a single trap, × 5.]