1. The Occipito Frontalis (fig. 166, A) arises in a web of fibers from the back of the skull, descends over the forehead, and is inserted into the eyebrow, where it mingles its fibers with those of the orbicularis palpebrarum. Its action is to raise or arch the eyebrow.

2. The Orbicularis Palpebrarum (fig. 166, B) is the muscle which closes the eyelids. The outer and stronger portion (represented by the darker lines in the engraving) draws down the eyebrows, and is the direct opponent of the occipito frontalis.

3. The Third Muscle (fig. 166, C) is properly a part of the first, and is called the descending slip of the occipito fronta lis; but as it descends on the side of the nose and is attached to the bridge, it has a different effect from the rest of the muscle-drawing down the extremity of the eyebrow, while the other portions are being raised.

4. The Corrugator Supercilii (fig. 166, D) arises from the lowest part of the frontal bone where it joins the bones of the nose, and running obliquely upward is inserted in the skin under the eyebrow. This muscle and the orbicularis palpebrarum, acting together, knit the eyebrows.

MUSCLES OF THE EYE.-What is called the Ocular Group consists of seven muscles.

1. The Levator Palpebra Superioris (fig. 167, 1) is the muscle which raises the upper eyelid, acting in opposition to the orbicularis. It arises deep

within the orbit, and is attached to the cartilage which gives firmness to the upper eyelid. It is long, thin, and triangular.

2. The Rectus Superior (fig. 167,) arises with the preceding, and is inserted

into the globe of the eye, which its action draws directly upward.

3. The Rectus Inferior (fig. 167, 13) arises from the inferior margin of the optic foramen (opening) and is inserted into

the lower surface of the globe, which its office is to draw downward.

4. The Rectus Internus (fig. 167, 10) is a short thick muscle arising from the common tendon and sheath of the optic nerve (fig. 167, 2), which almost conceals it in our drawing, and being inserted into the inner surface of the globe. Its action draws the eyeball toward the inner angle of the eye.

5. The Rectus Externus (fig. 167, 12), the extremity of which, at its insertion, is shown in our cut, is the antagonist of the preceding, and draws the globe toward the outer corner of the eye.

6. The Obliquus Superior (fig. 167,) arises from the mar gin of the optic opening, and is inserted into the sclerotic coat near the entrance of the optic nerve. Its office is to roll the eyeball inward and forward.

7. The Obliquus Inferior (fig. 167, ") (the opponent of the preceding) arises from the margin of the superior maxillary bone, and is inserted into the outer and posterior portion of the eyeball, which its action rolls outward and backward. MUSCLES OF THE NOSE.-We may enumerate four muscles

Fig. 168.

MUSCLES OF THE NOSE.

connected with the nose which have a physiognomical signification, and whose location and action should be understood by the student.

1. The Levator Labii Superioris alaqui Alæ Nasi, or elevator of the upper lip and wing of the nose (fig. 168, A), has its origin on the upper jaw-bone and descends to the lip; but a part of it stops short and is attached to the movable cartilage of the nostril, which it raises along with the upper lip.

2. The Depressor Ala Nasi, or depres sor of the wing of the nose (fig. 168, B) arises from the upper jaw-bone close to the sockets of the front teeth, and descending is inserted into the cartilage of the side of the nostril, which it draws down.

3. The Compressor Nasi, or compressor of the nose (fig.

168, C), arises from the bridge of the nose, and is inserted in the lateral cartilage of the nostril. As its name implies that, it compresses the nose; but it also expands the nostril by raising the lateral cartilage.

4. The Orbicularis Oris (fig. 168, D) belongs to the next group; but a slip from it, detaching itself from the mass of that muscle, runs up the edge of the septum of the nose.

THE LIPS AND CHEEKS.-The mouth is the center of expression, and it is here that the greatest number of muscles

connected with expression are concentrated. It is important that their location and action should be understood.

1. The Orbicularis Oris (fig. 169, A) is the circular muscle which surrounds the mouth, and to which the fleshy structure of the lips is in a great measure owing. It has properly no origin, its fibers being traceable continuously around the lips, which its office is to close. It is the opponent of many other muscles, which, taking their origin from the prominent bones of the face, are concentered toward the mouth, and, besides opening it, move the lips in various directions.

2. The Levator Labii Proprius (fig. 169, C) arises from the upper jaw, near the orbit, and is attached exclusively to the upper lip, which it raises.

3. The Levator Anguli Oris (fig. 169, D) lies under the last named, and is, of course, shorter. It raises the angle of

the mouth.

4. The Zygomaticus (fig. 169, E) arises from the zygomaa process of the cheek-bone (fig. 163, G) described in a previous section, which joins the temporal bone and helps to form the zygomatic arch-and is inserted into the angle of the

mouth. Its whole course may be seen in fig. 165 (H). There is sometimes an additional muscle arising and inserted in a similar manner, called the zygomaticus minor.

4. The Buccinator (some fibers of which may be seen at G, fig. 169) is a flat muscle which lines the inside of the cheek. It arises from the sockets of the back teeth of both jaws, and is inserted into the angle of the mouth, which its action draws back.

5. The Triangulis Oris, or Depressor Anguli Oris (fig. 169, H), is a comparatively powerful muscle arising from the lower jaw and inserted into the angle of the mouth, which it depresses. In the drawing, some muscular fibers (I) may be seen, which join the triangulis oris, and pass to the angle of the mouth. These are parts of the platysma myoides, a superficial muscle of the neck which mounts over the jaw to terminate in the cheek. The uppermost faciculus (bundle) represented in the drawing has been described by Santorini as a distinct muscle, and from its action in laughter has obtained the name of risorius (laughing muscle) Santorini.

6. The Quadratus Menti (fig. 169, K) is a small square muscle situated on the chin, which depresses the lower lip.

7. The Levator Menti (fig. 169, L) is a small muscle which arises from the lower jaw, near the sockets of the front teeth, and passes to be inserted into the integument of the chin. When this and the last-named muscle act together, they throw up the chin and project the lower lip. The levator menti is sometimes called superbus, from the look of lofty contempt which its action gives to the mouth.

We have now briefly described all the bones and muscles of the face and head that are prominently concerned in expression or in the formation of the more prominent signs of character. To some of these we shall have frequent occasion to refer, and the reader who can make himself master of their locations and offices will find his progress greatly facilitated; but in any case this chapter can readily be consulted, and will prove invaluable.

Fig. 170.

one

can fail to be struck with the great variety which exists in the form and quality of the chin. It may be prominent or retreating; long or short; broad or narrow; pointed, round, or square; double or single, coarse or delicate. Few attach any importance to these differences, supposing them to be merely accidental; but they are all significant, and it is our purpose in this chapter to show what they mean.

THE CHIN AND THE CEREBELLUM.

The chin corresponds in position with the cerebellum, and there is a close anatomical relation between the lower jaw, of which the chin forms a part, and the base of the back-head