COMMON NAME. Colic root.
    MEDICINAL PART. The root.
    Description. -- This is a delicate twining vine, with a perennial root. From this root proceeds a smooth, woolly, reddish-brown stem, the sixth of an inch in diameter, and from five to fifteen or eighteen feet long. The leaves average two to four inches in length, and about three-quarters of their length in width. They are glabrous on the upper surface, with soft hairs on the lower. The flowers are of a pale greenish yellow color, and are very small. The seeds are one or two in each cell, and flat.
    History. -- There are several species of yam-root which grow in the West Indies, and which the natives eat as we do potatoes, but these are not medicinally like the Dioscorea Villosa, which I have described above, and which is a slender vine growing wild in the United States and Canada, and found running over bushes and fences, and twining about the growths in thickets and hedges. The farther south we go the more prolific it is. It flowers in June and July. The root, which is the part used, is long, branched, crooked, and woody. From this is made a preparation called Dioscorein, or Dioscorin, which contains all its active qualities.
    Properties and Uses. -- Antispasmodic. Half a pint of the decoction has been used, in almost innumerable cases of bilious colic, with great good effect; the same is also employed for spasm of the bowels, and to allay violent nausea; especially, however, the unaccountable nausea of pregnant women. Dioscorein possesses the properties of the crude root in a marvellous degree. I use it mainly for bilious colic; it is the very best relief and promptest cure now known. I also give it in some forms of uterine disease (always, however, combined with other material of a similarly excellent character), but my use of it is chiefly for bilious colic, and for this I commend it to the public.
    Dose. -- Of the decoction, two to four ounces; tincture, twenty to sixty drops; Dioscorein, one to four grains.