Fig. 60. Anterior Aspect of the Neck, Superficial Layer. Adult. 



The Head is strongly inclined backwards. Plaiysma and part of the super- 

 ficial cervical fascia covering the right Sterno- Mastoid Muscle have been removed. 

 The right Sterno- Mastoid Muscle has therefore dropped backwards. 



Under the skin lies the Platysma, which, converging from both sides, only 

 reaches the middle line at the chin; it therefore does not cover the anterior 

 cervical region. Deep to it is the superficial layer of the cervical fascia which 

 is important because it pulls the Sterno-Mastoid Muscles towards the Middle line, 

 When the fascia is divided, — as necessar}' for dissecting purposes — these 

 muscles drop backwards and outwards. They cover, as is well seen, in Fig. 59. 

 when in their natural position, the large vessels of the neck at a much higher 

 level, than after division of the fascia. 



The Anterior Jugular Veins, anastomosing above with the Facial Vein, 

 end below in the jugular venous arch which connects the 2 External Jugular 

 Veins. This communication usually passes behind the Sterno-Cleido-Mastoid 

 Muscles. In some cases, the Anterior Jugular Veins terminate by joining one of 

 the Jugular Veins. 



The next layer comprises the Infrahyoid Muscles; the Sterno- Hyoid 

 converging above, the Sterno-Thyreoid, converging below. Thus, in the middle 

 line a space is formed which is broadest ('Yo inch) at the mid-point between the Hyoid 

 Bone and Sternum. The deep cervical fascia envelopes these muscles and covers 

 in this space. When this fascia is divided, the muscles mentioned sink downwards 

 and outwards, thus exposing Larynx, Isthmus of Thyreoid Gland and Trachea. 



In the Submaxillary Region the anterior bellies of the Digastric Muscles 

 converge towards the chin ; between these the ^tylo-H^oid Muscles and their 

 median raphe are visible; our figure shews a lymphatic gland in this region, 

 which is not uncommon. The attachment of the intermediate Tendon of the 

 Digastric to the Hyoid Bone varies; it is either bound down b\- an aponeurotic 

 continuation of the Fascia of the muscle which is fixed to the hyoid bone, or 

 the anterior beUy arises partly from the hyoid bone, either in a tendinous or in 

 a muscular origin. 



The distance between the intermediate tendon and the hyoid bone also 

 varies; thus the distance is much greater in this figure than in Fig. 63. 



Bursae are met with occasionally over the Pomum Adami and the space 

 between the Th3'reoid Cartilage and the Hyoid Bone. 



