328 



MUSCLES AND FASCIAE. 



arch ; its fibres pass downwards and forwards, to be inserted into the upper hal! 

 of the ramus and outer surface of the coronoid process of the jaw. The deep 

 portion of the muscle is partly concealed, in front, by the superficial portion ; 

 behind, it is covered by the parotid gland. The fibres of the two portions are 

 united at their insertion. 



Relations. By its superficial surface, with the integument ; above, with the 

 Orbicularis Palpebrarum and Zygomatici; and with Steno's duct, the branches 

 of the facial nerve, and the transverse facial vessels, which cross it. By its deep 

 surface, with the ramus of the jaw, and the Buccinator, from which it is separated 

 by a mass of fat. Its posterior margin is overlapped by the parotid gland. Its 

 anterior margin projects over the Buccinator muscle ; and the facial artery lies 

 on it below. 



The temporal fascia is seen, at this stage of the dissection, covering in the 

 Temporal muscle. It is a strong aponeurotic investment, affording attachment, 

 by its inner surface, to the superficial fibres of the muscle. Above, it is a single 

 layer, attached to the entire extent of the temporal ridge ; but below, where it 

 is attached to the zygoma, it consists of two layers, one of which is inserted 

 into the outer and the other into the inner border of the zygomatic arch. A 

 small quantity of fat, the orbital branch of the temporal artery, and a filament 

 from the orbital branch of the superior maxillary nerve, are contained between 

 these two layers. It is covered, on its outer surface, by the aponeurosis of the 

 Occipito-frontalis, the Orbicularis Palpebrarum, and Attollens Aurem and At- 

 trahens Aurem muscles ; the temporal vessels and nerves cross it from below 

 upwards. 



Fig. 218. The Temporal Muscle, the Zygoma and Masseter having been removed. 



Dissection. In order to expose the Temporal muscle, remove the temporal fascia, which may 

 be effected by separating it at its attachment along the upper border of the zygoma, and dis- 

 secting it upwards from the surface of the muscle. The zygomatic arch should then be divided, 

 in front, at its junction with the malar bone ; and behind, near the external auditory meatus, and 

 drawn downwards with the Masseter, which should be detached from its insertion into the ramus 

 and angle of the jaw. The whole extent of the Temporal muscle is then exposed. 



The Temporal (Fig. 218) is a broad radiating muscle, situated at the side of the 

 head, and occupying the entire extent of the temporal fossa. It arises from the 

 whole of the temporal fossa, which extends from the external angular process 

 of the frontal in front, to the mastoid portion of the temporal behind ; and from 



