Chorea, neglected or improperly treated, or too frequently pursuing its natural course, degenerates into paralysis agitans. There is a tremulous or violent motion of almost every limb. The spasms are not relaxed, but are even increased during sleep, and when the animal awakes, he rises with agitation and alarm. There is not a limb under the perfect control of the will; there is not a moment's respite; the constitution soon sinks, and the animal dies. No person should be induced to undertake the cure of such a case: the owner should be persuaded to permit a speedy termination to a life which no skill can render comfortable. Chorea is oftenest observed in young dogs, and especially after distemper; and it seems to depend on a certain degree of primary or sympathetic inflammatory affection of the brain. Chorea is often very plainly a consequence of debility: either the distribution of nervous power is irregular, or the muscles have lost their power of being readily acted upon, or have acquired a state of morbid irritability. The latter is the most frequent state. Their action is irregular and spasmodic, and it resembles the struggles of expiring nature far more than the great and uniform action of health. It is not the chorea that used to be described, in which there was an irresistible impulse to excessive action, and which was best combated by complete muscular exhaustion; but the foundation of this disease is palpable debility. [Rickets, bad feeding, cold and damp housing, worms in the alimentary canal, mange, and other chronic affections, are all forerunners of this malady.--L.] In the treatment of chorea there must be no bleeding, no excessive purgation, but aperients or alteratives, merely sufficient to keep the fæces in a pultaceous state, so as to carry off any source of irritation to the intestinal canal, and particularly some species of worms, too frequent sources of irritation there. To these should be added nutritious food, gentle exercise, tonic medicines, and general comforts. Counter-irritants may be applied--such as blisters over the head, and setons, extending from poll to poll--the application of turpentine, or the tincture of cantharides; but all of these will frequently be of no effect, and occasionally a rapid and fearful increase of irritability will ensue: antispasmodics are in this case of no use, and narcotics are altogether powerless. As for tonics, iron and gentian have been serviceable to a certain extent, but they have never cured the complaint. The nitrate of silver will be the sheet-anchor of the practitioner, and if early used will seldom deceive him. It should be combined with ginger, and given morning and night, in doses varying from one-sixth to one-third of a grain, according to the size of the dog.