VEINS OF THE NECK. 341 



The Transverse sinus (basilar, anterior occipital) passes transversely 

 across the basilar process of the occipital bone, forming a communication 

 between the two inferior petrosal sinuses. Sometimes there are two si- 

 nuses in this situation. 



VEINS OF THE NECK. 



The veins of the neck which return the blood from the head are the 



External jugular, 

 Anterior jugular, 

 Internal jugular, 

 Vertebral. 



The External jugular vein is formed by the union of the posterior auri- 

 cular vein with the temporo-maxillary, and commences at the lower bor- 

 der of the parotid gland, in front of the sterno-mastoid muscle. It de- 

 scends the neck in the direction of a line drawn from the angle of the 

 lower jaw to the middle of the clavicle, crosses the sterno-mastoid, and 

 terminates, near the posterior and inferior attachment of that muscle, in 

 the subclavian vein. In its course downwards it lies upon the anterior 

 lamella of the deep cervical fascia, which separates it from the sterno- 

 mastoid muscle, and is covered in by the platysma myoides and superfi- 

 cial fascia. At the root of the neck it pierces the deep cervical fascia ; it 

 is accompanied, for the upper half of its course, by the auricularis magnus 

 nerve. The branches which it receives are the occipital cutaneous and 

 posterior cervical cutaneous, and, near its termination, the supra and pos- 

 terior scapular. 



The external jugular vein is very variable in size, and is occasionally 

 replaced by two veins. In the parotid gland it receives a large commu- 

 nicating branch from the internal jugular vein. 



The Anterior jugular vein is a trunk of variable size, which collects the 

 blood from the integument and superficial structures on the fore part of 

 the neck. It passes downwards along the anterior border of the sterno- 

 mastoid muscle, and opens into the subclavian vein, near the termination 

 of the external jugular. The two veins communicate with each other, 

 and with the external and internal jugular vein. 



The Internal jugular vein , formed by the convergence of the lateral and 

 inferior petrosal sinus, commences at the foramen lacerum posterius on 

 each side of the base of the skull, and descends the side of the neck, 

 lying, in the first instance, to the outer side of the internal carotid, and 

 then' upon the outer side of the common carotid artery to the root of the 

 neck, where it unites with the subclavian, and constitutes the vena inno- 

 minata. At its commencement, the internal jugular vein is posterior and 

 external to the internal carotid artery, and the eighth and ninth pairs of 

 nerves ; lower down, the vein and artery are on the same plane, the glosso- 

 pharyngeal and hypoglossal nerves passing forwards between them, the 

 pneumogastric being between and behind in the same sheath, and the 

 nervus accessorius crossing obliquely behind the vein. 



The Bra?iches which the internal jugular receives in its course are, the 

 facial, the lingual, the inferior pharyngeal, the occipital, and the superior 

 and inferior thyroid veins. 



The Vertebral vein descends by the side of the vertebral artery in the 

 canal formed by the foramina in the transverse processes of the cervical 

 29* 



