60 ANATOMY AND PHYSIOLOGY. 



Lying on the side of the nose is a small triangular muscle which 

 dilates the nostril. Its action will be felt if the nose be caught 

 between the finger and thumb ; it then acts almost irresistibly, ex- 

 panding the nostril under the finger. A muscle is seen running 

 down the side of the nose, connected to its wing and to the upper 

 lip ; it raises the upper lip, showing the teeth, and dilating at the 

 same time the nostril. Lying deeper than this muscle, in the hol- 

 low above the eyetooth, is a small muscle running downward and 

 outward, which lifts the angle of the mouth. Further out, coming 

 from the prominence of the cheek-bone, are two long delicate 

 muscles, inserted into the angle of the mouth, which distort it 

 upwards and outwards, producing the depressed line which leads 

 from the side of the nose to the angle of the mouth. Below, in 

 the middle, is a muscle which depresses the under lip, and at the 

 angle is a triangular one, attached like the preceding to the lower 

 jaw, which draws down the angle of the mouth. All these are 

 called the muscles of expression, because they produce all the dif- 

 ferent modifications of the features which express the feelings, as 

 beautifully exhibited by Le Brun in his drawings illustrative of the 

 passions. 



It may be remarked here, that the muscles which express lively 

 feeling and the gayer passions, such as the muscle of the scalp^ the 

 elevator of the eyelid, the elevators and dilators of the lips, do for 

 the most part either raise or draw the parts from the middle line of 

 the face ; while those which manifest the sadder feelings and the 

 darker passions, as the one which knits the brows, and the de- 

 pressors of the lower lip and of the angles, either depress the parts, 

 or draw them to the middle line. The constant and habitual exer- 

 cise of either of these sets of muscles leaves corresponding perma- 

 nent folds in the skin, which are indicative of the habitual feelings 

 and passions of the individual. 



On the side of the face we see two muscles which are not con- 

 nected with the features, but with the action of mastication. One 

 of them is of an oblong square form, lying on the ascending plate 

 of the lower jaw ; it closes the jaw forcibly, and may be felt swell- 

 ing by the finger placed upon it when in action. Another is seen 

 coming forwards, and closing the side of the mouth; it is the muscle 

 which enables us to blow, as in playing on the flute, or in working 

 with the blowpipe. 



On the side of the neck, the superficial thin muscle, seen in figure 

 7, having been removed, a very large strong muscle is seen passing 



