But, again, the several muscles are interwoven, one with the other, and, moreover, tliey are difïerentiated frora the rest of the muscles of the bodv by the fact that not only the muscle as a whole, but also each single muscle-bundle, is capable of independent movement.
This, for instance, is the origin of dimples in the cheeks, through the isolated action of a muscle-bundle which terminates at that particular point in the skin, and contracts in the act of smiling.
There is an excellent description of the facial muscles in Merkel (1) and Langer (2). The muscles are the chiefest exponents of individuality, and possess for us here cjuite a subordinate interest as such. unless one chooses to reckon the delicate de vel op ment of facial expresion as one of the beauties of womanly perfection. To analyse in detail the expression of the face, which is the mirror of the soul, would be overstepping the limits of this book.
But one peculiarity of the facial muscles, which Langer has especially pointed out, deserves our particular attention.
At various places in the face, the termini of certain muscles are inwoven with the skin, for instance in the frontal region, in the ala: nasi, the lips and the chin. The limits of such inplantations are the eyebrows, and the oblique furrow between the chin and the lower lip, and further off, on both sides, two furrows, one of which descends from the ala nasi to the outer edge of the mouth, the other from the outer edge of the mouth to the chin; the latter is often united below the chin with the opposite furrow.
This muscular conformation affects the distribution of the fatty deposit in the face. The fatty layer cannot develope within the boundaries of the firmly cohering muscles; we therefore see, even in cases of pronounced obesity, that the forehead, nose, mouth and chin are preserved from it, whilst the above-mentioned furrows become more and more prominent vvhen there is a great accumulation of fat in the cheeks. One or more rolls of fat form at the chin beneath the combined line of the lip and chin; it is the wellknown double-chin.
As, therefore, a certain roundness of forms is peculiar to women,
(1) Merkel, Topographische Anatomie, J, p. 100.
(2) Anatomie der aüsseren For men, p. 129.