402 THE MUSCLES AND FASCIA 



inserted into the under surface of the jugular process of the occipital bone. This 

 muscle lies behind the internal jugular vein, and in front of the upper portion of 

 the vertebral artery. 



The Longus colli (m. longus colli) is a long, flat muscle, situated on the anterior 

 surface of the vertebral column, between the atlas and the third thoracic vertebra. 

 It is broad in the middle, narrow and pointed at each extremity, and consists 

 of three portions a superior oblique, an inferior oblique, and a vertical portion. 

 The superior oblique portion arises from the anterior tubercles of the transverse 

 processes of the third, fourth, and fifth cervical vertebrae, and, ascending obliquely 

 inward, is inserted by a narrow tendon into the tubercle on the anterior arch of 

 the atlas. The inferior oblique portion, the smallest part of the muscle, arises 

 from the front of the bodies of the first two or three thoracic vertebrae, and, ascend- 

 ing obliquely outward, is inserted into the anterior tubercles of the transverse 

 processes of the fifth and sixth cervical vertebra?. The vertical portion lies directly 

 on the front of the vertebral column; it arises, below, from the front of the bodies 

 of the upper three thoracic and lower three cervical vertebras, and is inserted 

 above into the front of the bodies of the second, third, and fourth cervical vertebrae. 



Relations. By its deep surface, with the prevertebral fascia, the pharynx, oesophagus, sym- 

 pathetic nerve, the sheath of the great vessels of the neck, the inferior thyroid artery, and the 

 recurrent laryngeal nerve; by its superficial surface, with the cervical and thoracic portions of 

 the vertebral column. Its inner border is separated from the opposite muscle by a considerable 

 interval below, but they approach each other above. 



Nerves. The Rectus capitis anticus minor and the Rectus lateralis are supplied from the 

 loop between the first and second cervical nerves; the Rectus capitis anticus major, by branches 

 from the second, third, and fourth cervical; the Longus colli, by branches from the second to 

 the seventh cervical nerves. 



Actions. The Rectus anticus major and minor are the direct antagonists of the muscles 

 at the back of the neck, serving to restore the head to its natural position after it has been drawn 

 backward. These muscles also serve to flex the head, and, from their obliquity, rotate it, so 

 as to turn the face to one or the other side. The Longus colli flexes and slightly rotates the 

 cervical portion of the vertebral column. 



8. The Lateral Vertebral Region (Figs. 309, 310). 

 Scalenus anticus. Scalenus medius. Scalenus posticus. 



The Scalenus anticus (m. scalenus anterior} is a conical-shaped muscle, 

 situated deeply at the side of the neck, behind the Sternomastoid. It arises 

 from the anterior tubercles of the transverse processes of the third, fourth, fifth, 

 and sixth cervical vertebrae, and, descending almost vertically, is inserted by a 

 narrow, flat tendon into the scalene tubercle on the inner border and upper 

 surface of the first rib. The lower part of this muscle separates the subclavian 

 artery and vein, the latter being in front, and the former, with the brachial plexus, 

 behind. 



Relations. By its superficial surface, this muscle is in relation with the clavicle, the Sub- 

 clavius, Sternomastoid, and Omohyoid muscles, the transversalis colli, and the suprascapular 

 arteries, the subclavian vein, and the phrenic nerve; by its deep surface, with the Scalenus medius, 

 pleura, subclavian artery, and brachial plexus of nerves. It is separated from the Longus colli, 

 on the inner side, by the vertebral artery. On the anterior tubercles of the transverse processes 

 of the cervical vertebrae, between the attachments of the Scalenus anticus and Longus colli 

 lies the ascending cervical branch of the inferior thyroid artery. 



The Scalenus medlUS (m. scalenus medius), the largest and longest of the three 

 Scaleni, arises from the posterior tubercles of the transverse processes of the lower 

 six cervical vertebrae, and, descending along the side of the vertebral column, 



