=Age of Horse from One to Nine Years, as Indicated by Teeth (Incisors) in Lower Jaw.=--The age of a horse is determined by: 1. The character of the teeth, i.e., whether they be temporary or permanent. 2. The period at which they are cut. 3. The condition of the teeth themselves. Temporary or milk teeth are distinguished from the permanent teeth by being smaller, whiter, and having more distinct necks. The fangs are small and have little attachment to the gums. The jaws are plump, fleshy, and round, and the teeth are arranged in something like a semicircle. Permanent teeth are larger, broader, wider in the necks and more discolored than milk-teeth. The plumpness and circularity of the jaw is less than in the young colt, and gradually decreases. In old age the teeth are arranged in a nearly straight line. During the first ten months the six incisors appear. At twelve months the teeth show little signs of wear, the corner teeth are mere shells, having no inner walls, and the teeth are close together. At two years the corner teeth have grown up to level of others; the centre teeth are worn. The teeth stand wide apart at necks because of growth of jaw. Shortly before three years old the two centre milk-teeth are shed and replaced by permanent teeth. Shortly before four years old the next two milk-teeth on either side are shed, and permanent ones appear. Shortly before five years old the corner milk-teeth are shed, and permanent ones appear, but as shells only, having no internal walls. At about six years old the inner wall of the corner teeth has grown up level with outer wall. The tusks appear at about three and one half years, are matured at six, and then begin to wear away. Usually absent in mares. Between three and five years the marks or cups in the permanent teeth are very plain. At _six_ the marks are well worn in centre teeth. At _seven_ the marks disappear from centre teeth, are well worn in the two next, but plain in corner teeth. At _eight_ the marks have all disappeared, except in corner teeth, in which they are worn. At _nine_ the marks are usually gone from all the incisor teeth in lower jaw. The temporary incisors in upper jaw fall out usually a little earlier than those in lower jaw. The permanent incisors in upper jaw are longer and larger than the lower, and the mark is deeper and remains longer than in the lower teeth. Beyond nine years the teeth become angular and foul, the tusks worn, and the age only to be determined accurately by much experience and observation. Old horses frequently suffer from uneven and sharp-edged grinders. Their mouths should be occasionally examined, particularly if the animal be off his feed, and, if necessary, the teeth should be rasped off. SICK HORSES. The horses on sick report are in charge of the stable sergeant, who reports daily to the captain for instructions as to their treatment.