The fact here recorded has certainly been generally overlooked; and Mr. Percival deserves the gratitude of his professional brethren for directing their observation to the point. Every practitioner, however, has met with instances in which the molars were implicated. There are two forms of disease to which these teeth are liable; caries, or decay, and a loss of vitality, or death. The death of a tooth has not hitherto been observed upon by veterinary authors, but it is not rare. The causes which may give rise to it cannot be accurately stated, though they may be conjectured. The vessels that nurture the fang and ramify through the pulp, are small and delicate; the alveolar cavities are thin, some of them in the upper jaw being not thicker in parts of their walls than brown paper. The force of the masticatory muscles is very great, and if any hard substance be taken between the teeth, it is easy to imagine that the minute arteries of the fang should thereby be ruptured. The effect produced upon the pulp, and the transient agony occasioned by biting a piece of hard crust, are familiar to every human being; nor can we suppose that the horse's teeth, especially when the greater strength of its muscles is duly considered, are not liable to similar and proportionably greater injury. There may be no history to such a case, no record of the date when the occurrence took place; for the horse is not always watched during the time of its feeding, nor were it watched, is it possible that the groom would attribute the sudden exhibition of pain to the right cause. The primary effect is therefore misinterpreted or unnoticed; but after a time it is remarked that the creature is longer than its companions emptying the manger; then it begins to quid its hay,--that is, the hay is taken into the mouth partially masticated and formed into a pellet or round mass; but instead of being swallowed, the prepared morsel is allowed to fall from the mouth. Should no advice be taken, the horse becomes bad in its coat, and loses flesh. No amount of corn, or extra grooming, will restore it to condition; medicines may be administered with no better effect. The disease is strictly local in its nature, and the constitutional symptoms are only sympathetic. Should the affection still be suffered to proceed unchecked, the animal is continually moving its lips; either it is restless in the stable, or leans the head against the manger, and neglecting the food which is before it, remains dull and quiet, the eyes half closed, and the breathing quickened. A dose of medicine seems to do it some temporary good, but the purgation has hardly ceased before the symptoms reappear; saliva runs from the mouth, and the food in the manger is rendered sloppy, almost like to a mash, before it is eaten; the bones of the face at last swell; the breath becomes fetid; and a thick offensive purulent discharge issues from one of the nostrils. That discharge is not