FASCIAE OP THE HEAD AND NECK. 277 



tion of the fluids in opposition to the laws of gravity; and in the palm 

 of the hand and sole of the foot is a powerful protection to the struc- 

 tures which enter into the composition of these regions. In some 

 situations its tension is regulated by muscular action, as by the tensor 

 vaginae femoris and gluteus maximus in the thigh, by the biceps in the 

 leg, and by the biceps and palmaris longus in the arm ; in other situa- 

 tions it affords an extensive surface for the origin of the fibres of 

 muscles. 



The fasciae may be arranged like the other textures of the body 

 into, 1. Those of the head and neck. 2. Those of the trunk. 3. 

 Those of the upper extremity. 4. Those of the lower extremity. 



FASCLE OF THE HEAD AND NECK. 



The TEMPORAL FASCIA is a strong aponeurotic membrane which 

 covers in the temporal muscle at each side of the head, and gives 

 origin by its internal surface to some of its muscular fibres. It is 

 attached to the whole extent of the temporal ridge above, and to the 

 zygomatic arch below ; in the latter situation it is thick and divided 

 into two layers, the external being connected to the upper border of 

 the arch, and the internal to its inner surface. A small quantity of 

 fat is usually found between these two layers, together with the or- 

 bital branch of the temporal artery. 



CERVICAL FASCIA. The fasciae of the neck are the superficial and 

 the deep. The superficial cervical fascia is a part of the common 

 superficial fascia of the entire body, and is only interesting from con- 

 taining between its layers the platysma myoides muscle. 



The deep cervical fascia is a strong cellulo-fibrous layer which in- 

 vests the muscles of the neck, and retains and supports the vessels and 

 nerves. It commences posteriorly at the ligamentum nuchaa, and passes 

 forwards at each side beneath the trapezius muscle to the posterior bor- 

 der of the sterno-mastoid ; here it divides into two layers, which embrace 

 that muscle and unite upon its anterior border to be prolonged onwards 

 to the middle line of the neck, where it becomes continuous with the 

 fascia of the opposite side. Besides thus constituting a sheath for the 

 sterno-mastoid, it also forms sheaths for the other muscles of the neck 

 over which it passes. If the superficial layer of the sheath of the 

 sterno-mastoid be traced upwards, it will be found to pass over the 

 parotid gland and masseter muscle, and to be inserted into the zygo- 

 matic arch ; and if it be traced downwards, it will be seen to pass in 

 front of the clavicle, and become lost upon the pectoralis major muscle. 

 If the deep layer of the sheath be examined superiorly, it will be 

 found attached to the styloid process, from which it is reflected to the 

 angle of the lower jaw, forming the stylo-maxillary ligament ; and if 

 it be followed downwards, it will be found connected with the tendon 



