PALPEBRAL REGION. 301 



edge of the aponeurosis of the Occipito-frontalis, and converge to be inserted 

 into a projection on the front of the helix. 



Relations. Superficially, with the skin ; deeply, with the areolar tissue derived 

 from the aponeurosis of the Occipito-frontalis, beneath which are the temporal 

 artery and vein and the temporal fascia. 



The Attollens auriculam (Auricularis superior), the largest of the three, is 

 thin arid 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 

 crania] surface of the pinna. 



Relations. Superficially, with the integument; dee}}ly, with the areolar tissue 

 derived from the aponeurosis of the Occipito-frontalis, beneath Avhich is the tem- 

 poral fascia. 



The Retrahens auriculam (Auricularis posterior] consists of two or three fleshy 

 fasciculi, which arise from the mastoid portion of the temporal bone by short 

 aponeurotic fibres. They are inserted into the lower part of the cranial surface 

 of the concha- 

 Relations. Superficially, with the integument; deeply, with the mastoid portion 

 of the temporal bone and the posterior auricular artery and nerve. 



Nerves. The Attrahens and Attollens auriculam are supplied by the temporal 

 branch of the facial; the Retrahens auriculam is supplied by the posterior' auricu- 

 lar branch of the same nerve. 



Actions. In man, these muscles possess very little action : the Attrahens auric- 

 ulam draws the ear forward and upward; the Attollens auriculam slightly raises 

 it: and the Retrahens auriculam draws it backward. 



3. Palpebral Region (Fig. 195). 



Orbicularis palpebrarum. Levator palpebrse. 



Corrugator supercilii. Tensor tarsi. 



Dissection (Fig. 194). In order to expose the muscles of the face, continue the longi- 

 tudinal incision made in the dissection of the Occipito-frontalis down the median line of the 

 face to the tip of the nose, and from this point onward to the upper lip ; and carry another 

 incision along the margin of the lip to the angle of the mouth, and transversely across the face 

 to the angle of the jaw. Then make an incision in front of the external ear, from the angle of 

 the jaw upward, to join the transverse incision made in exposing the Occipito-frontalis. 

 These incisions include a square-shaped flap, which should be removed in the direction marked 

 in the figure, with care, as the muscles at some points are intimately adherent to the 

 integument. 



The Orbicularis palpebrarum is a sphincter muscle, which surrounds the cir- 

 cumference of the orbit and eyelids. It arises from the internal angular process 

 of the frontal bone, from the nasal process of the superior maxillary bone in front 

 of the lachrymal groove for the nasal duct, and from the anterior surface and 

 borders of a short tendon, the tendo oculi, or internal tarsal ligament, placed at the 

 inner angle of the orbit. From this origin the fibres are directed outward, forming 

 a broad, thin, and flat layer, which covers the eyelids, surrounds the circumference 

 of the orbit, and spreads out over the temple and downward on the cheek. The 

 palpebral portion (ciliaris) of the Orbicularis is thin and pale; it arises from the 

 bifurcation of the tendo palpebrarum, and forms a series of concentric curves, which 

 are on the outer side of the eyelids inserted into the external tarsal ligament. The 

 orbital portion (orbicularis latus) is thicker and of a reddish color: its fibres are 

 well developed, and form complete ellipses. The upper fibres of this portion blend 

 with the Occipito-frontalis and Corrugator supercilii. 



Relations. By its superficial surface, with the integument. By its deep surface, 

 above, with the Occipito-frontalis and Corrugator supercilii, with which it is inti- 

 mately blended, and with the supra-orbital vessels and nerve ; below, it covers the 

 lachrymal sac, and the origin of the Levator labii superioris algeque nasi, the Leva- 

 tor labii superioris, and the Zygomaticus minor muscles.. Internally, it is occa- 

 sionally blended with the Pyramidalis nasi. Externally, it lies on the temporal 



