324 ORGANS OF EXPRESSION. 



supplied. They have been already detailed. The veins 

 have corresponding names and situation with the arteries, 

 and terminate in the jugular. 



The nerves (Fig. 74, 91, 9<T) supplying the mouth and 

 pharynx come from the fifth, the seventh, eighth, and 

 ninth pair of the cerebral nerves, and from the sympa- 

 thetic system. 



CHAPTER III. 



ORGANS OF EXPRESSION. 



THESE comprise the muscles concerned in giving expres- 

 sion to the various passions, which are chiefly the occipito 

 frontalis, corrugator supercilii, pyramidalis nasi, compressor- 

 nasij and orbicularis palpebrarum, (Fig. 55.) The facial 

 nerve (Fig. 97) must also be included in the organs of 

 expression, as it is the motive power of the muscles. 



Occipito-frontalis. Dissection. Commence an incision 

 from the root of the nose, and carry it through the integu- 

 ment, along the median line of the cranium, as far back as 

 the tuberosity of the occipital bone. Make a second in- 

 cision parallel with, and about half an inch above the 

 eyebrow, and connect it with the first. Make a third 

 incision from the posterior extremity of the first, upon 

 either side of the occipital protuberance, along the superior 

 transverse ridge of this bone. Commence dissecting off the 

 integuments at the transverse incision, and this muscle will 

 be* exposed. The adhesion between this muscle and the 

 scalp is very close, and this, added to the paleness of its 

 fibres* makes the dissection both difficult and tedious, re- 

 quiring caution and perseverance to succeed. The scalp 

 being removed, this muscle is seen to consist of four fleshy bel- 

 lies two anterior covering the forehead, and two posterior 

 investing the occiput, with an intervening and expanded 

 aponeurotic structure, covering the superior and lateral por- 

 tions of the cranium. It arises by two fleshy bellies, with ten- 

 dinous fibres, from the superior transverse ridge of the 



