The muscles of the face, which are attached to the skin, move and alter the shape of its folds and apertures. These different cutaneous parts are very complex, but at the same time known to persons who are the greatest strangers to anatomy. For them even it is unnecessary to describe here the eyebrows, the eyelids, the palpebral fissure, the ala or wing of the nose, and the lips. We will only point out, with regard to these parts, the significance of their various anatomical names, the employment of which will be useful in abridging the descriptions that follow.

On the eyebrow we distinguish a broad internal part (towards the median axis of the face) called the head of the eyebrow, and an external part called the tail of the eyebrow, which becomes thinner as it is removed from the middle line.

On each palpebral fissure, at its inner end, is a small perforated papilla—the lachrymal papilla—the perforation in which is named the punctum lachrymale, carrying the tears from the surface of the eye into the nose by special ducts. Each of the two extremities of the palpebral fissure bears the name of the canthus, or angle. We distinguish, therefore, on the eyelids an external canthus or angle characterised by its pointed form, and an internal characterised by its rounded form, bounding a small oval space called the lachrymal lake, at the bottom of which a rose-coloured fleshy tubercle projects (the caruncula lachrymalis). External to this is a pale fold, the plica semilunaris, a rudiment of the third eyelid (found in birds). We also give the name of commissure (or angle) to each extremity of the buccal aperture (commissure of the lips). The groove extending from the septum of the nose to the centre of the upper lip is known as the philtrum.

Lastly, we must note a fold which normally exists in a more or less marked degree in every subject, and the changes of which take a great part in the expression produced by the various muscles of the cheeks. This is the naso-labial fold, so named because, arising from the region bounded by the cheek and the side of the nose, it is directed obliquely downwards and outwards, passes at a short distance from the posterior border of the wing of the nose, and terminates near the commissure of the lips. In the subject who served for the experiments of Duchenne (Fig. 99, page 320) this fold was strongly marked, as it generally is in all old people.

The human head and face, the features, and the muscles which underlie the skin have, it is supposed, undergone progressive and retrogressive changes in the process of evolution. The cranium has expanded with the evolution of the brain, while the face has become smaller and feebler, and the teeth have shown distinct signs of degeneration and diminution, both in size and number.

Of the soft parts of the face, the apertures of the eyes and mouth have increased in mobility and functional power and refinement of expression; while the nasal apertures and the ears illustrate a retrogression in evolution. The interior of the nasal cavity as well as the nostrils presents a simpler or more degenerate type in man than in the lower animals, in whom the sense of smell is so much more highly developed. The external ear is a good example of a rudimentary organ. Its parts have a definite form, and each wrinkle or corrugation has a separate name (see Fig. 93). It is composed of a mass of elastic cartilage (except in the tip or lobule) which penetrates into the passage of the ear in a tubular form. This cartilaginous pinna is the shrivelled-up remains of the mobile funnel-shaped ear of the lower animals; and the tip of the ear is represented by an angular projection (Darwin’s tubercle) placed on the edge of the rim of the ear (helix).

The lobule is soft, and consists of a mass of fat enclosed in the skin. It is usually free from the neck, but in some cases (as, for example, in the right ear of the poet Byron) the lobule is attached to the skin of the neck, and is not in full relief. The muscles of the nose and ear are also degenerate, and the movements of the nostrils and of the ears are only rudimentary.

In the same way the arrangement of the muscles underlying the skin of the neck and head presents examples of advance or retrogression when compared with the similar muscles of lower animals.

In hairy animals the body is covered all over by a thin layer of muscle which underlies the skin, and is called the panniculus carnosus.

In man the body has become almost denuded of hair, except on the head and face, and at the same time his capacity of facial expression is vastly greater than in one of the lower animals.

The effect of these changes is seen in the condition of the panniculus carnosus. It has degenerated over the hairless trunk, and only remains normally as the platysma myoides of the neck. But, on the other hand, the parts of the panniculus carnosus which have swept over the face and have surrounded the apertures of the eye and mouth in particular, have become differentiated into the complicated series of muscles of expression, rudimentary and feeble on the scalp and in relation to the pinna and the nasal opening, but highly organised in relation to the apertures of the eye and mouth.

It is for the most part these highly differentiated muscles which have to be dealt with in this chapter in connection with the expression of the emotions.

The muscles of expression (Fig. 94) are arranged in three series: one around the eyes and eyebrows, occupying the upper region of the face; the second about the nose; and the third around the aperture of the mouth, occupying the middle and especially the lower region of the face. The first series includes the occipito-frontalis, the corrugator supercilii, and the orbicularis palpebrarum; the second includes the pyramidalis nasi, compressor naris, and dilator alæ nasi; the third set is most numerous, comprising the levator labii superioris alæque nasi, levator labii superioris, zygomaticus major and minor, the levator anguli oris, the orbicularis oris (to which we may add the buccinator), the risorius, depressor anguli oris, and depressor labii inferioris. Finally, in the neck and extending up to the lower jaw is the platysma myoides, which takes a considerable part in certain powerful expressions of the face.

In the study of these muscles we will enter but little into anatomical details, but will content ourselves with pointing out the situation of the muscle, its fixed attachments to the bones of the face, its direction, and, lastly, the point on the skin where it takes its insertion. On the other hand, we must carefully inquire into its mechanism and the manner in which its contraction produces alterations in the skin of the face, and the nature and direction of the folds which it marks thereon. We must ask ourselves what expression results by the occurrence of these alterations in the face. And, lastly, we will endeavour to give a diagram of this expression after the mode of representation employed by Humbert de Superville (page 298).

A.—Muscles of the upper part of the face (forehead, eyebrows, eyelids, and root of nose.)

1st. Occipito-frontalis muscle (muscle of attention).—This muscle (1, Fig. 88, page 285) (Fig. 94) consists of an anterior and a posterior belly, connected by an intermediate membranous tendon covering the scalp. Its anterior belly extends as a fleshy sheet, quadrilateral in form, over each lateral half of the forehead. The muscles of each side are continuous with one another across the middle line. The anterior muscular portion is the frontalis. Its lower border is attached to the skin of the eyebrow, and blends with the orbicularis palpebrarum. From this origin its fibres ascend vertically and parallel to each other towards the region of the roots of the hair, and become continuous, at this level, with the membranous expansion of the epicranial aponeurosis. This aponeurosis, which covers the vault of the skull and is adherent to the skin of the scalp, is prolonged backwards to the occipital region, where it terminates in a bilateral fleshy layer, the occipitalis muscle, attached to the superior curved line of the occipital bone.

In order to understand the mechanism of the occipito-frontalis muscle it is necessary to consider it as taking its fixed origin at the posterior part of the skull, through the medium of the epicranial aponeurosis and the occipitalis portion of the muscle; its insertion is its attachment to the deep surface of the skin of the eyebrow and the orbicularis palpebrarum. It has no bony attachment in the region of the forehead. The frontalis, therefore, in contracting, draws the skin of the eyebrow and the upper eyelid from below upwards, and consequently raises the eyebrow, and causes transverse folds to appear in the skin of the forehead.

In examining (Fig. 95) a face in which this muscle is contracted we perceive that it expresses attention; if the contraction of the muscle is very great this expression of attention changes to that of astonishment. In entering into the detail of the changes that the face then presents we see that the eyebrow is raised and its superior convexity is very marked, that the eye is widely opened, clear, and brilliant, and that the forehead is furrowed on each lateral half by curved folds concentric with the curve of the eyebrows, continued more or less from one side to the other, and describing curves in the middle line with the concavity upwards. In a child or young woman, in whom the skin is supple and elastic, it does not give rise to the formation of folds, and the skin of the forehead remains quite smooth during the contraction of the frontal muscle, and then the elevation of the eyebrow, the exaggeration of its curve and the state of the eyes, open and bright, are sufficient to give the expression of attention.

Figure 96 is the representation of attention, characterised here solely by the form of the eyebrows and the frontal folds.

2nd. The orbicularis palpebrarum (6, Fig. 88, and 10, Fig. 94).—The orbicular muscle of the eyes is a very extensive muscle which encircles the palpebral orifice. It is composed of numerous portions which can act more or less independently, and which have not all an equal importance in the expression of the face.

a. One part of this orbicular muscle, called the palpebral part, is contained in the thickness of the eyelids, and produces by its contraction the closing of the eyes. If this contraction is moderate it produces only a certain drawing together of the eyelids and reduces the opening of the eyes to the form of a linear slit. This state of the palpebral opening does not constitute by itself an expression, properly speaking, but it may be complementary to various expressions; thus, associated with a slight contraction of the triangular muscle of the lips, which is the muscle of disgust and discontent (page 333), it gives to the countenance the expression of disdain and contempt.

b. A second part of the orbicular muscle is arranged in a circular manner on the outer side of the eyelids, and corresponds exactly to the contour of the orbital orifice of the skeleton (Fig. 58, page 174, and Fig. 88, page 285). This portion, which we may call the orbital portion, is divided into two parts: one, the inferior fibres, the contraction of which moves the lower eyelid slightly upwards and causes a furrow at its junction with the cheek, and without being expressive by itself, completes the expression of laughter by giving to it a character of frankness and truth; and the superior fibres, which merit more detailed study, for they produce by their action a characteristic expression of reflection, meditation, and contemplation.

This superior orbital portion of the muscle (muscle of reflection) is placed beneath the skin of the eyebrow, and its fibres, like it, describe an arc with the concavity downwards, of which the inner extremity is adherent to the internal border of the orbital opening. The mechanism, therefore, of this muscle is easily foreseen; for, like all curved muscles, more or less fixed at their extremities, it must in contraction straighten its curve. It accordingly acts in this way on the eyebrow, to the skin of which it is adherent, and effaces its curve, rendering it straight transversely; and it depresses, and consequently makes tense, the skin of the forehead, causing its wrinkles to disappear.

In examining a face in which this muscle is contracted we perceive that it expresses reflection. In Figure 97, owing to the excessive development of the eyebrow, which is greatly lowered, the hairs descend over the eyes, and the expression is rather that of painful reflection or of intense application of the mind pre-occupied with sadness; but we see in every case that this expression is obtained essentially by the lowering and straight direction of the eyebrow, which veils the eye and effaces all wrinkles on the forehead. This alteration in the features is precisely the reverse of that produced by the frontalis muscle, as is shown by the comparison of Figures 95 and 96, and in fact the two states of mind corresponding to the expression given by each of the muscles are precisely the reverse of each other. We cannot be at the same time attentive to an external object and meditating in reflection. Usually the succession of these states of mind and facial expression is as follows:—We are attentive to that on which we are looking, the eye open, brilliant, the eyebrow raised, and the forehead wrinkled (contraction of the frontal muscle); afterwards we reflect on what we have seen, and are, so to speak, abstracted from the external world—the eyebrow is lowered, the forehead smooth, and the eye veiled (by contraction of the superior fibres of the orbicularis palpebrarum), or the eyes may be closed (by contraction of the whole of the muscle).

Figure 98 is the representation of reflection, characterised by the absence of the frontal folds, the depression of the eyebrows and the presence of two small vertical folds in the space between the eyebrows, to which the depression of the eyelid gives rise (Fig. 97). This representation of reflection (Fig. 98) does not acquire its full demonstrative significance until we compare it with that of attention (Fig. 96).

3rd. Pyramidalis nasi muscle (or muscle of menace).—This small muscle, situated in the space between the eyebrows on a level with the root of the nose (11, Fig. 94) (9, Fig. 88, page 285), is formed by short vertical fibres, which is attached by its lower end to a membranous expansion over the nasal bones (Fig. 58, page 174), and by its upper end to the deep surface of the skin of the space between the eyebrows.

The contraction of this muscle therefore produces the following result:—Taking its fixed insertion at the nasal bones, it draws downward the skin of the space between the eyebrows, forming short transverse folds, and depressing slightly the inner part of the eyebrow.

In a face in which this muscle is contracted (see the atlas of Duchenne) the expression is that of harshness, menace, and aggression. Looking at the expression of countenance which Duchenne reproduced by this contraction, we can readily believe that if the subject had been represented in full, its attitude would have been one of menace; and the individual would be shaking his fist or brandishing a weapon. Moreover, anything which throws a shadow or a dark look between the eyebrows gives to the physiognomy a character of harshness, as when the contraction of the pyramidalis produces the transverse folds in this region. Therefore, in those persons in whom the eyebrows seem to meet, owing to an exaggerated development of hair in the space between, the physiognomy always presents at first sight the stamp of severity and harshness, which may not agree in the least with the true character of the subject. The expression of the pyramidalis is too delicate, and due to a change of the features too local and slight for us to express it by a drawing, as we have done in the case of the preceding muscles.

4th. Superciliary muscle (corrugator supercilii, or muscle of pain).—This short muscle is deeply hidden beneath the skin of the region of the head of the eyebrow. Its fixed attachment is to the frontal bone, above the superciliary arch; from this origin its fibres are directed outwards and slightly downwards to be inserted into the deep surface of the skin at the middle of the eyebrow.

Its mechanism consists in drawing the eyebrow inwards and slightly upwards, and as it is attached to the middle of the eyebrow it draws it together at this point, namely, towards its inner part. The eyebrow is therefore, so to speak, abruptly hooked upwards and inwards, like a curtain that has been tucked up and attached to a fixed point. It therefore produces on the skin of the forehead folds concentric to this gathering together of the eyebrow and situated in the middle of the forehead, besides producing the vertical furrows, obvious in the figures, between the eyebrows.

Figure 99 represents, after a photograph of Duchenne, the state of the physiognomy caused by the contraction of the superciliary muscle. This physiognomy has an expression characteristic of suffering, and any greater accentuation of the action of the muscle shows in a marked degree the expression of physical or mental agony.

We see that the only parts changed in this expression (compare Fig. 95, page 315) are the inner half of the eyebrow and the region between the eyebrows on the forehead; pain, therefore, is expressed by the raising of this part of the eyebrow and its gathering together abruptly in the middle of the forehead, and by the presence of the short folds immediately above this and the more extended folds occupying the middle region of the forehead.

Figure 100 is a diagrammatic representation of pain, expressed only by changes in the neighbourhood of the inner part of the eyebrow (contrast with Fig. 102 following).

B.—Muscles of the middle region of the face.

5th. The great zygomatic muscle (zygomaticus major, muscle of laughter).—This muscle (17, Fig. 94, and 11, Fig. 88) has its fixed attachment on the cheek-bone; from this origin it is directed obliquely downwards and forwards, to be inserted into the deep surface of the skin near the angle of the mouth.

6th. Elevator of the angle of the month.—The levator anguli oris is a muscle which largely aids the great zygomatic muscle in its action. It arises from the canine fossa of the upper jaw, and is directed downwards towards the angle of the mouth. It is inserted into the skin, and blends with the orbicularis oris (15, Fig. 94).

The mechanism of these muscles consists in drawing the angle of the mouth upwards and outwards, an action which results in some complex changes in the expression of the countenance. At first the orifice of the mouth is enlarged transversely, and its direction ceases to be straight, so that each lateral half is directed obliquely upwards and outwards. As the naso-labial line (Fig. 95) passes, at its lower end, near the commissure of the lips, this also is carried upwards, describing a slight curve concentric to the commissure of the lips, while the upper part of the line describes a curve with its convexity downwards. The skin of the cheek gathered up towards the cheek-bone becomes more prominent, and forms, below the outer angle of the eye, several radiating folds (commonly called crows’-feet), which throw a slight shadow beneath the external angle of the eye; this makes it appear as if the line of the eyelids is a little raised on the outer side (or oblique upwards).

Figure 101, representing the contraction of the great zygomatic muscle, illustrates in a diagram the frank expression of gaiety and laughter, and we see that the alterations of expression take place only, as we have already said, in the line of the lips, the naso-labial line, and the external angle of the eyes.

Figure 102, giving the representation of laughter according to the preceding description of the great zygomatic muscle, is very similar to the corresponding figure of Humbert de Superville (Fig. 92, page 299), only, in order to express the reality without having regard here to appearances, we have drawn the lines of the eyes horizontal; and, again, the naso-labial furrow has been represented with its form convex downwards and inwards for the upper two-thirds, and with the slight hook which its inferior extremity describes. This naso-labial furrow is of the utmost importance in the expressions produced by all the muscles belonging to the lips, as we shall see in the following description.

7th. The lesser zygomatic (zygomaticus minor) and elevator of the upper lip (levator labii superioris, muscle of grief).—On the inner side of the great zygomatic muscle there exists frequently (10, Fig. 88, page 285), but not constantly, a small muscular fasciculus which arises from the anterior part of the cheek-bone and descends to be inserted into the thickness of the upper lip. This muscle, called the lesser zygomatic, does not take part in the expression of laughter; in fact, it changes the naso-labial furrow in the same manner as the following muscle (the external common elevator), and so expresses, as we shall see, emotion, sadness, and grief.

8th. The elevator of the upper lip (levator labii superioris) arises (14, Fig. 94, and 14, Fig. 88, page 285) from the inferior border of the bony margin of the orbit and descends to the upper lip.

Its contraction raises the upper lip itself, but not the labial commissure, so that each half of the line of the lips, raised within and remaining depressed at its outer extremity, becomes slightly oblique from above downwards and from within outwards (the reverse of the obliquity produced by the great zygomatic muscle); at the same time the centre of the naso-labial furrow is raised and the furrow becomes curved with its concavity downwards and inwards (the reverse of the curve produced by the great zygomatic).

By means of these changes the countenance takes on the expression of discontent, emotion, and grief (see the atlas of Duchenne).

We give here only one drawing (Fig. 103) in which are shown the two essential changes produced by this muscle (obliquity of the line of the lips and curve of the naso-labial furrow), which seems to us to show in a satisfactory manner the expression of grief in tears. We comprehend the value of this drawing better by comparing it with Figure 102. We see that the changes produced by the muscle of grief (lip and naso-labial furrow) are precisely the reverse of those produced by the muscle of laughter (zygomaticus major), just as the two corresponding emotions are the reverse of each other. We remark also how slight is the distance which separates these two muscles, and how delicate are the shades of anatomical arrangement which separate them, so delicate that authors do not agree as to whether the muscle found between them, the lesser zygomatic muscle, when it exists, should be considered as associated with the great zygomatic or, as we think, with the common elevator of the nose and upper lip. Beyond doubt their anatomical relations should remind us, in the nature of the emotions and their expression, how small a distance there is between laughter and tears.

9th. The elevator of the nose and upper lip (levator labii superioris alæque nasi, muscle of sobbing, of weeping bitterly).—This muscle (13, Fig. 94, and 7, Fig. 88) arises above from the inner border of the orbit; it descends almost vertically to be inserted by some of its fibres into the wing of the nose, and by the majority into the upper lip, not far from its central portion.

It therefore raises the middle part of the lip, the labial commissure remaining fixed, and gives accordingly to each half of the line of the lips a direction oblique downwards and outwards (like the preceding muscle, but in a more characteristic manner); at the same time it dilates the nostril by raising the wing of the nose; lastly, by the traction that it exercises vertically on the skin of the naso-labial furrow, it raises en masse the inner and upper part of this furrow and renders it straight, causing it to form a species of groove wherein the tears flow when they pour abundantly from the inner angle of the eyelids. These changes (see the atlas of Duchenne) give to the countenance the expression of grief with abundant tears, or of weeping bitterly.

The drawing of Figure 104 renders this expression to a certain degree, but it is difficult to realise it with the simple elements we use in these formulæ. We see that all the folds of the face converge towards the inner angle of the eye, or towards the point of attachment of this muscle.

10th. Transverse muscle of the nose (compressor naris, muscle of lasciviousness).—This muscle (12, Fig. 94, and 9, Fig. 88) is attached at its origin to the skin of the cheek on a level with the side of the nose, and is directed transversely forwards over the nose to join a thin aponeurosis which stretches over the bridge of the nose, and receives the insertions of these two muscles, and that of the pyramidalis nasi.

This aponeurosis, which covers the bridge of the nose, forms a fixed point towards which these muscles draw the skin of the cheek and nose, so as to mark on the lateral surface of the nose a series of vertical folds (perpendicular to the direction of the muscle).

Duchenne considered the change produced by these muscles to be characteristic of the expression of lasciviousness. Perhaps this muscle by itself is not sufficiently expressive, but when its contraction accompanies that of certain other muscles, we find very clearly in the physiognomy the element of lewdness pointed out by Duchenne. In his atlas this author gives the photograph of a countenance in which he had produced contraction of the frontalis, the great zygomatic, and the compressor naris; a countenance of which the expression may be directly interpreted as that of an old man in whom the attention (frontalis muscle) is agreeably excited (great zygomatic) by a spectacle arousing lewd ideas (compressor naris); the face produced by Duchenne would be, for example, a study in physiognomy for the head of the old man in the classic subject of Susanna in the bath.

We have not attempted to represent by a drawing an unsatisfactory and perhaps doubtful idea of the expression of this muscle.

C.—Muscles of the lower part of the face.

11th. Orbicularis muscle of the lips (orbicularis oris).—In the substance of the lips, as in the eyelids, a muscle is found, the fibres of which surround the orifice of the mouth—the orbicularis oris (19, Fig. 94, and 15, Fig. 88). This muscle principally possesses functions not primarily pertaining to expression, but to the various uses of the lips—prehension of food, mastication, speech, suction, etc.; the part it takes in physiognomy, although of importance, is secondary to these elemental functions. As in the orbicular muscle of the eyelids, we distinguish in it internal fibres corresponding to the free border of the lips and external fibres more peripherally placed. If the inner fibres only contract (internal orbicular) they close the mouth, and, diminishing the size of the orifice, cause the red surfaces of the lips to be brought closely together in their whole extent. If the outer fibres (external orbicular) contract only, they project the lips forwards and render their surfaces prominent and rounded, as in the expression of pouting or in kissing.

We need not dwell at length on the muscle which constitutes the fleshy layer of the cheeks and forms the lateral walls of the cavity of the mouth. This muscle, called the buccinator (buccinare, to play the trumpet), is a thin sheet of muscle (21, Fig. 94) lining the hollow of the cheek in front of the line of the masseter. It is separated from that muscle posteriorly by a pad of fat (the remains of a suctorial pad), which in the infant is an important aid in suckling, and may be seen projecting into the side of the mouth. It takes a part in movements associated with the actions of the tongue and lips; it plays an important part in mastication by bringing beneath the crown of the teeth the food which passes outside the alveolar arches. It also aids in the articulation of sounds (speech) and in whistling and the playing of wind instruments (whence its name of buccinator), for it is the contraction of this muscle that expels from the mouth the air which inflates the cheeks. By its insertion into the angle of the mouth, where its fibres decussate with those of the orbicularis muscle, the buccinator is able to some extent to assist in the retraction of the mouth, as in grinning or snarling.

12th. The depressor of the angle of the mouth (depressor anguli oris, muscle of contempt).—This muscle belongs to the lower lip. It forms (22, Fig. 94, and 16, Fig. 88) a triangular layer, of which the base is attached to the lower jaw, external to the symphysis of the chin, and from this origin its fibres converge towards the angle of the mouth, where, by its apex, it is inserted into the deep surface of the skin.

This muscle depresses the labial commissure, and therefore renders the line of the lips oblique in a direction downwards and outwards; again, it draws downwards the lower extremity of the naso-labial furrow so as to render this furrow almost straight, except at its lower end, which describes a slight curve embracing the labial commissure.

The expression produced by a slight contraction of this muscle is that of sadness; marked contraction produces the expression of contempt. We have already seen (page 319) that a partial closing of the eyelids usually helps to complete the expression of contempt. Two other movements assist in this expression—a contraction of the common elevator of the nose and upper lip, raising the ala of the nose and curling the lip upwards; and a movement of the head to the opposite side. All these movements may have, as Darwin pointed out, a rational physical basis—the expression of the mouth implying a disagreeable taste, the uplifting of the nose an unpleasant smell, and the aversion of the head a disgusting sight.

Figure 105, copied from Duchenne, renders well, by the contraction only of the two triangular muscles of the lips, the expression of discontent and scorn. The depression of the angles of the mouth is characteristic, and the naso-labial furrow, very marked in the subject under experiment, is greatly changed in its direction and in the form of its inferior extremity, according to the mechanism that we have explained.

Lastly, the drawing of Figure 106 gives, so to speak, a diagrammatic formula of contempt by means of the form of the inferior part of the naso-labial furrow, and the concentric folds which it produces below the angle of the mouth.

13th. The depressor of the lower lip (quadratus menti: depressor labii inferioris, muscle of disgust).—This muscle (23, Fig. 94, and 17, Fig. 88), partly hidden by the depressor anguli oris, arises from the anterior part of the body of the lower jaw; from this origin the fibres ascend obliquely upwards and inwards to be inserted into the whole length of the lower lip.

This muscle’s action is to depress the lower lip, turning it outwards more or less strongly, so as to produce the grimace characteristic of a person who, having introduced into the cavity of the mouth a morsel of food which he does not find to his taste, rejects it forcibly, forming a species of groove with the lower lip turned outwards; if the contraction is less energetic the physiognomy expresses disgust.

We must refer to the atlas of Duchenne for the reproduction of this expression, always more or less rude, and have not attempted a drawing with a simple line as an indication of the labial fissure.

14th. Platysma muscle of the neck (platysma myoides).—In each lateral half of the anterior surface of the neck is a thin muscular sheet situated beneath the skin (25, Fig. 94, and 25, Fig. 74, page 217). This platysma muscle is attached below to the upper part of the chest, from which origin its fibres are directed obliquely upwards and forwards towards the lower jaw, to be inserted into the edge of the jaw, and the skin of the chin, of the lower lip, and the commissure of the lips; the more superior fibres sweep forwards in a horizontal direction across the cheek towards the labial commissure, and constitute the risorius muscle of Santorini (20, Fig. 94).

The platysma, which is not of itself essentially a muscle of expression, adds its contraction to that of various muscles of the face, so as to give to the corresponding expression a character of terrible energy; the risorius muscle does not therefore produce the expression of laughter (of gaiety), but only that of grinning, of forced laughter, threatening or sneering. The platysma in all these cases acts by depressing the lower jaw, slightly opening the mouth, and drawing the labial commissure downwards; it marks at the same time a series of transverse folds on the skin of the neck. These elements are capable of giving to the physiognomy a terrible character, which Leonardo da Vinci has well observed, in his chapter on the mode of representing a person in a state of violent anger, where he says, “it makes the sides of the mouth into a bow, the neck thick and swollen, and marked with wrinkles in front.”

If the characteristic changes produced by the contraction of the platysma of the neck occur along with the contraction of the frontalis muscle, the countenance, as shown in Duchenne’s series of photographs, takes on an expression of attention and astonishment such as might be produced by a terrible spectacle. Associated with the contraction of the superciliary muscle, the expression becomes that of acute pain, as, for example, in a wretch under torture, or a victim torn by a beast of prey. If the contraction of the pyramidalis nasi is accompanied by that of the platysma we have the expression of a savage and barbarous threat.

General considerations.—Associations and combinations.—From the enumeration we have made of the facial muscles from the forehead to the neck, we must perceive that among these muscles there are some which are by themselves completely expressive (e.g., the frontal, superciliary, and great zygomatic), and others which are expressive only in a complementary sense, or intended only to complete or change an expression produced by another muscle (such are the palpebral portion of the orbicularis of the eyelids, and the platysma of the neck), and lastly, others which are almost non-expressive, but yet associated with the true muscles of the expression (e.g. the buccinator). But we have not space here to dwell on these classifications.

A more important question is that of the association of the action of various muscles, and especially of the muscles which are completely expressive by themselves. The expression peculiar to each of these muscles is, so to speak, one of the syllables or words of the language of physiognomy, but, like every other language, physiognomy associates these syllables and words to arrive at its expressions. Now experience shows that usually the associations and combinations are composed of few elements. Usually two suffice; three muscles are sometimes in play simultaneously, hardly ever four.

Again, if we endeavour to realise these combinations theoretically by supposing the contractions of two muscles associated at random, we soon perceive that among the combinations some are easy and ordinary, and this is on account of the nature of emotions which we suppose associated, and the mechanism of the corresponding muscles, while others are impossible for the same reason.

The following is an example of easy combination related at the same time to the emotions and also to the muscular mechanism—viz., the combination of the contraction of the frontalis and of the great zygomatic muscles, as expressive of attention and laughter. On the one hand, attention (frontalis) might be excited by a spectacle which provokes laughter (zygomatic); on the other hand, the frontal muscle and the great zygomatic being situated the one in the forehead and the other in the cheek, acting, one on the eyebrow, the other on the lips, the mechanism of one is independent of that of the other; this, however, from an anatomical point of view, does not prevent the two contracting simultaneously, exactly as the biceps might contract in order to flex the forearm, at the same time that the common extensor of the fingers extends the digital phalanges.

On the other hand, as impossible combinations discordant both to sentiment and muscular mechanism, we may, for example, consider the simultaneous contraction of the frontalis and the superior orbital portion of the orbicularis muscles of the eyelids. The first muscle expresses attention, the second reflection, or two opposite states of the mind, which cannot at the same time be open to external phenomena, and meditating on internal analyses. Again, the first muscle raises, the second depresses the eyebrow, which cannot be at the same time drawn in two opposite directions; just as, to take an example from the muscles of the limbs, the forearm cannot be at the same time flexed by the action of the biceps and extended by that of the triceps.

By submitting them to the same analysis we see that nothing is easier or more concordant to their mechanism and to the emotions than the simultaneous contraction of the frontalis and the depressor anguli oris (attention and contempt), of the superciliary and the depressor labii inferioris (pain and disgust), the pyramidalis and the common elevator of the nose and upper lip (menace and sorrow), etc. On the contrary, for the same double series of reasons we find impossible and discordant associations, such as those of the great zygomatic and the depressor labii inferioris (gaiety and disgust), the pyramidalis and the superciliary (menace and pain), and of the common elevator of the nose and upper lip and the great zygomatic (sorrow and laughter).

There are, however, combinations which at first sight appear discordant to the nature of the passions, but which are found, notwithstanding, not to have any obstacle to their realisation in the mechanism of the countenance. We take, for example, the superciliary and the great zygomatic: one expresses pain, the other laughter—two expressions of an opposite nature; however, as these muscles correspond, one belonging to the head of the eyebrow, the other to the labial commissure, they can act without one counteracting the other, and we may well understand their simultaneous contraction. Now on reflection we find that this association, anatomically possible, is often realised, notwithstanding the apparent incompatibility of the corresponding passions. In the midst of violent physical pain, which causes the involuntary and irresistible contraction of the superciliary, a serene and powerful will finds still the energy to smile. In order to find the realisation in a work of art it is sufficient to study the expression of the countenance of Seneca in the painting by Giordano. A similar example is offered by that of a young woman who has become a mother, and who, though still quivering with the pain of childbirth (superciliary muscle), is divided betwixt the physical pain and the mental joy of seeing the infant to whom she has given birth and at whom she smiles (great zygomatic muscle).

These latter examples show that the anatomical conditions take the lead up to a certain point of those conditions which result from the nature of the emotions, and that a combination of expressions is possible only when it can be realised by the action of the facial muscles.

We will finish here these short studies of the anatomy of the face, happy if we have been successful in showing the artist that in the movements of the face there is neither fancy, caprice, nor inspiration, but that all is subject to exact and precise rules which are the orthography of the language of physiognomy, and that the possible combinations are both large and varied, so that the artist can preserve his liberty of action while conforming to these rules, as the poet observes those of grammar without being on that account embarrassed in the scope of his genius.