THE CERVICAL MUSCLES. 



549 



And, finally, the superior oblique portion is formed by slips arising from the trans- 

 verse processes of the sixth to the third cervical vertebrae and joining the upper part 

 of the medial portion. 



Nerve-Supply. — From the anterior divisions of the second, third, and fourth 

 cervical nerves. , 



Action. — To bend the neck ventrally and laterally. 



Fig. 544. 



Anterior tubercle of atlas 



Longus colli, superior oblique 

 portion 1 



Rectus capitis anticus major 



Lotigus colli, median portion ^ 



Longus colli, inferior oblique — • 

 portion 



Scalenus medius 



Scalenus anticus 



I rib 



Clavicle 



Vll cervical vertebra 

 I thoracic vertebra 



Deep dissection of neck, showing prevertebral muscles. 



2. Rectus Capitis Anticus Major (Fig. 544). 



Attachments. — The rectus capitis anticus major (m. longus capitis) partly 

 covers the upper part of the longus colli. It arises by four tendinous slips from the 

 transverse processes of the third to the sixth cervical vertebrae, and passes directly 

 upward to be inserted, into the basilar portion of the occipital bone, lateral to the 

 pharyngeal tubercle. 



Nerve-Supply. — From the anterior divisions of the second, third, and fourth 

 cervical nerves. 



Action. — To flex the head and rotate it slightly towards the opposite side. 



