i^ 



65Q Dl. HARKIS H. WILDER, 



II. Ligaments and Fasciae. 



'l'he osseo - cartilaginous framework of the head is reinforced by 

 a system of connective tissue, disposed between and îibout the muscles 

 in the form of ligaments and fasciae. 



These are partially exposed by the removal of the integument, 

 and being conspicuous and constant, serve as important anatomical 

 landmarks, and thus deserve special mention. As their dissection 

 must take place pari passu with that of the muscles, they cannot be 

 described in order of preparation as with the muscles, but must receive 

 a simple anatomical description. 



1 . Ligamentum i n t e r m u s c u 1 a r e posterius. 



This ligament forms a septum of connective tissue, extending from 

 the skull, through the muscles, to the superficial fascia. 



It lies between the masseter and the mass of dorsal muscles and 

 arises from a transverse ridge upon the Os petroso- occipitale, which 

 extends from the median line outwards and backwards to the posterior 

 exterior angle of the skull. 



Its anterior surface gives origin to the posterior fibres of the 

 masseter, while the dorsal muscular mass is inserted into its posterior 

 surface. Anteriorly it becomes continuous with the digastric fascia 

 (v. inf.). 



2. Ligamentum intermuscul are 1 aterale. 



This ligament arises from the sharp lateral ridge of the skull, 

 which is formed by the quadrate, tympanic and occipito-petrosal bones; 

 and stretches as an horizontal partition between the masseter above 

 and the digastricus below. 



At its free outer edge it becomes continuous with the investing 

 fascia of the digastricus (q.v.). 



3. L i g a m e n t u m inte r m u s c u 1 a r e a n t e r i u s. 



This is possibly the temporal fascia of higher animals. It arises 

 along a line drawn between the posterior inner corner of the tempo- 

 ralis muscle and the antorbital process. 



From this origin it expauds and serves first as a separating wall 

 between temporalis and masseter, and then, extending forward beside 

 the eye, serves as a support to the optic and deep ophthalmic nerves. 

 Still anterior to this, the ligament gradually losses itself in the con- 

 nective tissue of the upper lips, lateral to the nasal capsule. 



