Fig. 123.—The same, sixteen years old.
Simultaneously there is a drooping of the corners of the mouth, which, when exaggerated in infancy, forms the characteristic and charming grimace of a child who is on the point of crying. Accordingly, sorrow draws the frontal zone upward, and the labial zone downward; in other words, it lengthens the face.
Expression of Pleasure.—On the contrary, laughter and happiness shorten the face; all the muscles are brought into play that stretch the corners of the mouth, as well as those which raise the upper lip, in consequence of which the upper teeth are disclosed.
The frontal zone remains in repose; excepting that there is a contraction of the orbicular muscle of the eyelids, especially in its lower portion; the lower lid is drawn upward and the skin is puckered at the external angle of the eye; the lachrymal gland is compressed, the circulation of blood stimulated, as always results from every expression of joy, the secretion of the gland is increased, and consequently a few tears are readily shed. The eye, grown smaller and half hidden, shines brilliantly, because moistened from without and irrigated from within by an abundant flow of blood.
Expression of Various Emotions: Anger.—During anger the superciliary muscles prevail in exceedingly energetic action, drawing the forehead strongly downward, wrinkling it vertically, and also producing transverse wrinkles on the nose. In the labial zone the orbicular muscle is intensely active, and the lips contract. When anger endures for a long time, the condition above described diminishes in intensity, leaving only a slight frown, while the closed lips protrude in tubular form. An expression usually described by the terms, to sulk or pout.
This is the way in which little children express their displeasure; and the pouting lips sometimes rise clear to the tip of the little nose, in sign of proud defiance. This form of grimace is common to the children of every race: it has been observed in the children of Hottentots and Chinese, as a sign of prolonged anger and ill humor.
Hence the contraction of the mouth is a characteristic sign of anger; and when the emotion is very strong, even the masticatory muscles may enter into play, causing a grinding of the teeth.
Surprise.—In surprise, on the contrary, the entire labial zone is in repose, and there is complete and free contraction of one muscle alone, the frontal; consequently it produces longitudinal lines across the entire forehead, uplifting the eyebrows, which passively follow the elevation produced by the frontal muscle, forming two arches around which the wrinkles of the forehead form themselves in parallel lines. The eyes in consequence are stretched to their widest. The oral zone is so far relaxed that the lower jaw droops in obedience to gravity and the mouth gapes open: bouche béanie. Sometimes a less intense degree of surprise fails to do away with the contraction of the orbicular muscle of the lips, which, without being actively contracted, but simply because relieved from the interference of antagonistic muscles, closes the mouth in a rounded or tubular aperture.