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surrounds and forms the aperture itself, the other nine are pairs, and radiate from this as from a centre.

The proper elevator of the upper lip extends from the lower border of the orbit to the upper lip, lying close to the border of the common elevator of lip and nose. When the lip is raised without raising the nose, which is not a very easy act, this muscle is the instrument.

The elevator of the angle of the mouth lies beneath the preceding, and partly concealed by it.'

"The zygomatici are two narrow fasciculi of muscular fibres, extending obliquely from the most prominent point of the cheek to the angle of the mouth, one being larger and longer than the other.' The elevator of the angle of the mouth, and the zygomatic muscles, serve to retract the angle of the mouth in smiling; they are therefore muscles of expression.

The two former of these four muscles are concerned in raising the upper lip, but they do not act very powerfully, or conspicuously. In fact, the upper lip is a feature remarkable for fixity, as compared with the under lip, and is not often elevated in man, and, on the occasions when it is raised, this is done by the common elevator rather than by its own proper muscles.

The region of the lower jaw contains three muscles, the depressor of the angle of the mouth, the depressor of the lower lip, and the elevator of the lower lip.

The depressor of the angle of the mouth lies at the side and lower part of the face, being extended from the angle of the mouth to the lower jaw.

The depressor of the lower lip is a small square muscle, lying nearer to the middle line of the chin than the preceding, by which it is partly concealed. It arises from the fore part of the lower jaw-bone, and is inserted into the lower lip, its fibres becoming blended with those of the orbicular muscle of the mouth, having been previously united with those of its fellow on the opposite side.

The elevator of the lower lip arises from a slight pit below the teeth-sockets of the lower jaw, near the middle line of the

jaw, and is inserted into the tegument of the chin, which it lifts when in action.

The remaining muscles of the mouth are unconnected with either jaw, having a sort of middle position between them.

'At each side of the face, in the part called the 'cheek,' is a muscle, the buccinator; and, round the margin of the mouth, one-the orbicularis oris.

The buccinator is a thin, flat plane of muscular fibres, quadrilateral in figure, occupying the interval between the jaws.' This muscle is exerted in masticating the food, and receives nerves from the same source as the masseter, which is one of the principal muscles engaged in the act of mastication.

The orbicularis oris 'belongs to the class of sphincter muscles, and like them is elliptic in form, and composed of concentric fibres, so placed as to surround the aperture of the mouth, but with this peculiarity, that the fibres are not continued from one lip into the other. The muscle is flat and thin; its inner surface being in contact with the coronary artery of the lips, labial glands, and the mucous membrane; the external with the skin and the fibres of the different muscles which converge towards the margin of the mouth.'

'The aperture of the mouth is susceptible of considerable dilatation and contraction; the former being affected by the different muscles which converge to it, and which may be compared to retractors drawing with different degrees of obliquity the lips, or their angles, in the direction of their respective points of attachment. The elevators are necessarily placed at the upper part of the face, the depressors in the opposite situation, and the proper retractors on each side; and these are the zygomatici and the buccinators. The buccinators also contract and compress the cheeks; this power is brought into play when any substance becomes lodged in the interval between them and the jaws.'-QUAIN, p. 256.

18. With regard to the instinctive play of those various muscles under Emotion, the first remark to be made is, that in the gay and pleasing emotions the face is opened out

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laterally by the action of the muscles that draw the parts away from the middle line. The principal muscles engaged in this action are the buccinator and zygomatici for the mouth, and the occipito-frontalis for the eyebrows. On the other hand, in painful states, the features are drawn towards the middle line by the action of the corrugator for the eyebrows and the orbicularis for the mouth. The expansion and contraction are also observable from above downwards; for the action that separates the eyebrows lifts them, while the corrugator both draws together and depresses the same parts. Again, in the mouth, the contraction takes place partly by the closing of the lips, but also by the action of two of the muscles of the lower lip, namely, the depressor of the angle of the mouth and the elevator of the lower lip. These last are remarkably uniform in the expression of painful feeling, and are seen at the earliest stage of infancy. They curve the mouth downwards, as the smile curves it slightly upwards. Thus it is that in painful states the features are puckered and contracted, both from without inwards and from above downwards; while in the opposite state they are expanded in all ways.

19. The second remark is, that it is often the relaxation of a certain class of muscles, more than their excitement, which gives expression; of this, smiling and laughter furnish the most apposite examples.' The relaxation of the orbicular muscle of the mouth allows the retracting muscles to preponderate, without any unusual exertion being thrown into those muscles. We may even go so far as to assert that while the milder forms of gaiety and satisfaction are associated with a relaxed state of the orbicular and other muscles, pain produces an intense and energetic contraction generally, and this intensity is even more a part of its character than the excitement of special muscles. Thus, in pain we may have an energetic expansion of the face as well as a contraction, but we are sure to have an intense exertion of some kind or other. The tones of the voice are sharp and loud, indicating a vivid stimulus of the organs. So in the gestures of the body; it is not easy to specify any one gesture that always accompanies a painful excitement, for we usually calculate on seeing a

general excitement and energy of gesture in various forms, If a person sitting at ease is seized with a painful spasm, the excitement will probably throw him into an erect posture; if he happens to be standing, the flexor muscles are likely to be stimulated so as to bend or crouch the body with violence. When intense pleasure excites the system there is the same indiscriminate vehemence of action, and it is only by the more expressive organs-the voice and the features-that we know which passion is prevailing.*

20. I remark, in the third place, that a certain class of emotional states are marked out by their depressing action, or by their depriving all the muscles and motor centres of tone and energy. This is noted by Müller in the passage already quoted. Terror and grief, especially in their later stages, or after a certain amount of excitement has been discharged, are of this nature. The depression is first felt, like all other emotional stimuli, in the lungs and heart, and passes from these to the voice, the features, the carriage. The enfeebled respiration is occasionally assisted by a forced or voluntary act suggested by the sense of oppression, and this yields a sigh. The relaxation of the retractor muscles of the face, from exhaustion, has an effect the opposite of the smile, and the mouth is undistended, being opened only for the purpose of breathing. The whole expression is a sort of undress of the features, as during a general weariness.

nance.

In sorrow, a general languor pervades the whole counteThe violence and tension of grief, the lamentations and the tumult, like all strong excitements, gradually exhaust the frame. Sadness and regret, with depression of spirits and fond recollections, succeed; and lassitude of the whole body, with dejection of the face and heaviness of the eyes, are the

*In pain, the body is exerted to violent tension, and all the emotions and passions allied to pain, or having their origin and foundation in painful sensations, have this general distinction of character, that there is an energetic action or tremor, the effect of universal and great excitement. It must at the same time be remembered, that all the passions of this class, some more immediately, others more indirectly, produce in the second stage exhaustion, debility, and loss of tone, from over-exertion.'-BELL, Anatomy of Expression, p. 154.

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most striking characteristics. The lips are relaxed, and the lower jaw drops; the upper eyelid falls and half covers the pupil of the eye. The eye is frequently filled with tears, and the eyebrows take an inclination similar to that which the depressors of the angles of the lips give to the mouth.'Anatomy of Expression, p. 151.

21. There are states marked by the opposite of this character. Astonishment, for example, has a stimulating effect upon the organs of movement, and probably all that is peculiar in its expression may be attributed to this effect. The lungs are quickened, the mouth is opened and fixed to facilitate the breathing; the nostrils may be slightly distended for the same reason. The wide stare of the eyes is a result of anything strongly arresting the gaze, partly reflex, partly voluntary, and, it may be, in some degree emotional. This expression may be studied to great advantage in infants; in them we may see both the respiratory effects and the arrested gaze, the eyelids and eyebrows both being strongly elevated. The throwing out of the arms is a usual accompaniment of the state, and may be either secondary to the increased action of the chest, or that along with a primary effect of the emotion. There is a great tendency to throw the arms outward in making a vigorous respiration; but this would probably not of itself account for the action to the full extent that we see it, and I therefore assume also that the emotional state extends its influence to the extremities, as any emotional state is free to do.

The following is an interesting sentence on Laura Bridgeman, the blind deaf-mute at Boston. 'When Laura is astonished or amazed, she rounds and protrudes her lips, opens them, breathes strongly, spreads her arms, and turns her hands with extended fingers upwards, just as we do when wondering at something very uncommon.' These being in her case as unprompted by imitation as the earliest movements of infancy, we may look upon them as the original or instinctive effects of the emotion.

The case of respiratory action quickened to convulsion I shall speak of under the special instances where it occurs.