AURICULAR REGION. 319 



aponeurosis below the coronal suture. The inner margins of the two frontal 

 portions of the muscle are joined together for some distance above the root of 

 the nose ; but between the occipital portions there is a considerable though 

 variable interval. 



The aponeurosis covers the upper part of the vertex of the skull, being con- 

 tinuous across the middle line with the aponeurosis of the opposite muscle. 

 Behind, it is attached, in the interval between the occipital origins, to the occi- 

 pital protuberance and superior curved lines above the attachment of the Tra- 

 pezius; in front, it forms a short angular prolongation between the frontal 

 portions ; and on each side, it has connected with it the Attollens Aurem and 

 Attrahens Aurem muscles ; in this situation it loses its aponeurotic character, 

 and is continued over the temporal fascia to the zygoma by a layer of laminated 

 areolar tissue. This aponeurosis is closely connected to the integument by a 

 dense fibro-cellular tissue, which contains much granular fat, and in which 

 ramify the numerous vessels and nerves of the integument ; it is loosely con- 

 nected with the pericranium by a quantity of loose cellular tissue, which allows 

 of a considerable degree of movement of the integument. 



Nerves. The frontal portion of the Occipito-frontalis is supplied by the facial 

 nerve ; its occipital portion by the posterior auricujar branch of the facial, and 

 sometimes by the small occipital. 



Actions. The frontal portion of the muscle raises the eyebrows and the skin 

 over the root of the nose ; at the same time throwing the integument of the 

 forehead into transverse wrinkles, a predominant expression in the emotions 

 of delight. By bringing alternately into action the occipital and frontal por- 

 tions, the entire scalp may be moved from before backwards. 



2. AURICULAR KEGIO^. (Fig. 215.) 



Attollens Aurem. Attrahens Aurem. 



Eetrahens Aurem. 



These three small muscles are placed immediately beneath the skin around 

 the external ear. In man, in whom the external ear is almost immovable, they 

 are rudimentary. They are the analogues of large and important muscles in 

 some of the mammalia. 



Dissection. This requires considerable care, and should be performed in the following 

 manner : To expose the Attollens Aurem ; draw the pinna or broad part of the ear downwards, 

 when a tense band will be felt beneath the skin, passing from the side of the head to the upper 

 part of the concha ; by dividing the skin over the tendon, in a direction from below upwards, 

 and then reflecting it on each side, the muscle is exposed. To bring into view the Attrahens 

 Aurem. draw the helix backwards by means of a hook, when the muscle will be made tense, and 

 may be exposed in a similar manner to the preceding. To expose the Retrahens Aurem, draw 

 the pinna forwards, when the muscle being made tense may be felt beneath the skin, at its inser- 

 tion into the back part of the concha, and may be exposed in the same manner as the other 

 muscles. 



The Attollens Aurem, the largest of the three, is thin, and fan-shaped; its 

 fibres arise from the aponeurosis of the occipito frontalis, and converge to be 

 inserted by a thin, flattened tendon into the upper part of the cranial surface 

 of the pinna. 



Relations. Externally, with the integument ; internally ', with the temporal 

 aponeurosis. 



The Attrahens Aurem, the smallest of the three, is thin, fan-shaped, and its 

 fibres pale and indistinct ; they arise from the lateral edge of the aponeurosis 

 of the Occipito-frontalis, and converge to be inserted into a projection on the 

 front of the helix. 



Relations. Externally, with the skin; internally, with the temporal fascia, 

 which separates it from the temporal artery and vein. 



The Retrahens Aurem consists of two or three fleshy fasciculi, which arise 



