The genus _Datura_ is nearly allied to _Brugmansia_, but it may be easily distinguished by its calyx, which divides when the ovary begins to swell, and the upper part drops off, leaving only the lower part to enfold the capsule. The corolla of all the species of Datura is funnel-shaped, and the limb, in the large-flowered kinds, often shows marks of the plaits in which it lay when it was folded in the bud. There are five distinct stamens, which are generally enclosed in the mouth of the corolla. The capsule is fleshy when young, and in most of the species it is covered with spines. This is the case with _D. Stramonium_ (the common Thorn-apple), _D. Tatula_, and _D. Metel_, all of which have also their stamens enclosed; but in _D. ceratocaulon_ the capsule is smooth and the stamens exserted, that is, they project beyond the tube of the corolla. The genus Brugmansia is distinguished by its calyx being ventricose, and only two or three cleft; it is also strongly ribbed. The corolla is funnel-shaped, the tube being strongly ribbed; and the limb is five-lobed, the lobes being cuspidate, that is, drawn out into abrupt points. The flowers are drooping, and in _Brugmansia suaveolens_, formerly _Datura arborea_, they are very fragrant. The anthers grow together. The capsule is two-celled, smooth, and of a golden yellow, and the seeds are each covered with a thick corky skin. In _Solandra_, a nearly allied genus, the calyx bursts on one side, and the lobes of the corolla are not cuspidate, but rounded and fringed. The stamens also project beyond the mouth of the corolla, and the capsule is four-celled. The species of Solandra are all stove-trees. TRIBE III.—VERBASCINEÆ. The plants included in this division differ from those in the preceding ones, in not having the corolla plaited in the bud, and in having the anthers only one-celled; distinctions which have been thought of sufficient importance to induce many botanists to make this tribe a separate order.