Tournefort's method, which is established upon the figure of the flower, takes it into the first class among such plants as have campaniform or bell-shaped flowers.
Dr. Van Royen, whose system is undoubtedly a very elegant attempt towards the natural method in botany, arranges it among such as he calls Oligantheræ; namely, such plants as have the stamina equal to, or fewer in number than, the segments of the corolla.
Dr. Haller, whose method is upon the plan of a natural one also, includes the Bella-donna among the Isostemones, such plants as have the number of the stamina equal to the segments of the corolla.
In the sexual system of Linnæus, at this time so generally received, and so well established, it belongs to the Pentandria monogynia, or such plants as have five stamina and one style. The plants of this order are arranged into five subdivisions. The Atropa comes in among those, that have declinated stamina. According to this method, we shall give its generical characters from the last edition of Linnæus's Genera Plantarum.
The most obvious and essential character of the genus is the globose berry, and open calyx[8]. The general character is as follows.
Atropa Linn. Gen. Plant. Ed. 5. Nº. 222.
The calyx is a gibbous permanent perianthium, formed of a single leaf divided into five acute segments.
The corolla is formed of a single bell-shaped petal, the tube of which is very short; the limb ventricose, of an oval figure, and longer than the calyx. The mouth is small, expanded, and divided into five pretty equal segments.
The stamina are five subulated filaments proceeding from the base of the flower, and are of the same length: at the base they are connivent, and at the top bent outwardly. The antheræ are thick and assurgent.
The germen is of a semiovated figure: the style is filiform, of the length of the stamina, and inclinated. The stigma is capitated, transversely oblong, and assurgent.