Baldness, the falling off of the hair, (from Alopecia 375 a fox,) because the fox is subject to a distemper that resembles it. Athrix, Depilis, Pha-lacrotis; when particularly on the sinciput, Calvities, and Calvitium; which Galen thinks is owing to a defect of moisture. When the bald part is smooth and winding, like the track of a serpent, it is called ophiasis: but the general name of all the different appearances of bald places is area; and the hair is said to fall off areatim, by shedding; whence in general this disease is called area.

Celsus says, that the alopecia comes at any age, but the ophiasis only affects infants. In childhood, it often succeeds the tinea, achores, and favi.

The cause is a disease of the roots of the hair. Galen says, that eating mushrooms may occasion these disorders; and that malignant or contagious diseases of various kinds may produce the same effect.

The alopecia spreads itself on the beard, as well as on the hairy scalp, and is irregularly formed. The ophiasis usually begins at the back part of the head, and creeps about the breadth of two fingers, till it hath extended its two extremities to both the ears, and sometimes to the forehead. It seems to be more malignant than the alopecia, since the cuticle is also corroded so far as the roots reach; the skin also changes its colour, and is pale, or darker coloured, and, if pricked, a serous blood issues out.

In the tinea the excoriations and exulcerations are deeper, and often the hair does not grow again.

In infants these disorders commonly go off as age advances; but in adults, the cure, especially of the ophiasis, is very difficult. In proportion as a redness appears readily on rubbing the part, the cure may be expected to be easy. If a leprosy is the cause, the case is more difficult of cure. The most favourable is when hairs begin to push out on the edges of the areas.

If any other disease attends, its removal will often cure the alopecia. If the disease is formed, the head must be shaved, then washed with lye in which are in-uised the abrotanum and other warm stimulants: the part must then be rubbed until the skin grows red, and gentle stimulants should be continued. See Celsus, Sennertus.