Most of these are not very important substances, as they have rarely been employed as poisons in this country. Serious symptoms have, however, resulted from their accidental use. HENBANE (_Hyoscyamus niger_).—All parts of this plant are poisonous; but the seeds are more powerful than the root or leaves. In medicinal doses it is a feeble narcotic. It owes its powers to an alkaloid (_hyoscyamia_) it contains. In very large doses henbane produces giddiness, flushings, excitement, and a sense of weight in the head; the limbs tremble, and there is general loss of power, the pupils get dilated, there is double vision, flashing of light before the eyes, and great drowsiness. If vomiting supervene these symptoms generally pass off; otherwise we may find fierce delirium, loss of speech, complete loss of power over the limbs, cold sweats, and exhaustion. In some instances, when the roots have been eaten by mistake for parsnips, the symptoms have been those of drunkenness and delirium. Dr. Houlton states (_Lancet_, 6th July, 1844) that this error was committed one night at a monastery. The monks who partook of the roots had such hallucinations that the establishment resembled a lunatic asylum. They rang the bell for matins at midnight, and those who attended were unable to read, or they read that which was not in the book. In another reported case (_Edin. Med. and Surg. Journal_, p. 562, October, 1844), the roots were put into soup, of which nine persons partook. Although no unpleasant flavor was noticed at the time of eating, yet very shortly afterwards all complained of an acrid taste, nausea, indistinctness of vision, restlessness, delirium, and great somnolency, which continued some time. The appearances found after death consist chiefly of great congestion of the venous system. The lungs and brain have especially been found loaded with dark-colored blood. To prevent a fatal result from the use of henbane or others of this group, we must trust to stimulant emetics, as sulphate of zinc, and full doses of castor oil, so as to get rid of the offending substance. _Test._—The only test for hyoscyamus is the botanical characters of the plant, when taken in substance, and its power (common to all in this group) of dilating the pupil. ATROPA BELLADONNA (_Deadly Nightshade_).—Two other plants known under the name of Nightshade will hereafter be referred to. The Deadly Nightshade, now to be noticed, is indigenous, and grows in woods and gardens. The root, leaves, and berries are poisonous, this property being due to the presence of an alkaloidal principle—_Atropia_.