VEINS OF THE HEAD AND NECK 611 



its dilated portion, re})reseiits what was the left duct of Cuvicr and part of the 

 sinus venosus in thctVetus. As stated at pat^c GOo, it is occasionally found jjcrvious, 

 and may be greatly enlarged, and help to form the so-called left superior vena cava. 

 There is, as might l)e gathered from the consideration of its morphology, no valve 

 "where the ol>li(iue vein is continued into the coronary sinus. 



The right marginal vein— sometimes called the anterior cardiac vein, or vein 

 of Galen — runs over the right ventricle, along the right margin of the heart, and 

 opens either into the right auricular vein or separately into the lower part of the 

 right auricle, its orifice, known as the foramen of Galen, being situated immediately 

 below the opening of the superior vena cava. Other small veins — the smaller 

 anterior cardiac veins (venae cordis parvae, or preventricular veins; — also 

 track U}) from the anterior surface (if the right ventricle, and o})en either into the 

 riglit marginal vein or separately into tlie right auricle. 



2. THE VEINS OF THE HEAD AND NECK 



The veins of the head and neck may be divided for purposes of description 

 into the superficial, which return th*e blood from the external parts of the head 

 and neck; and into the deep, which return the blood from the deeper structures. 

 The superficial may be again subdivided, according to the region from which they 

 carry the blood, into (1) The veins of the scalp and face; and (2) the veins of the 

 neck. The deep veins — into which, moreover, some of the superficial open — may 

 be subdivided into; — (1) The veins of the diploe; (2) the venous sinuses; (3) the 

 veins of the brain; (4) the veins of the nasal cavities; (5) the veins of the ear; 

 (6) the veins of the orbit; (7) the veins of the pharynx and larynx; and (8) the 

 deep veins of the neck. All the veins, whether superficial or deep, sooner or later 

 termiriate in the internal jugular, the external jugular, the vertebral, or the deep 

 cervical vein — chiefly the two former; and these veins open directly or indirectly 

 into the innominate veins at the root of the neck, through which all the blood from 

 the head and neck ultimately passes on its way to the heart. The external jugular 

 vein is quite superficial; it is formed by the confluence of the veins corresponding 

 to the upper branches of the external carotid artery, and, after receiving tributaries 

 from the superficial parts of the neck and from the shoulder, terminates just above 

 the clavicle in the subclavian vein. The internal jugular vein is deeply placed liy 

 the side of the common and internal carotid arteries. It begins in the jugular 

 fossa, where it is continuous wdth the lateral sinus, and, after receiving tributaries 

 corresponding to the low'er })ranches of the external carotid artery, terminates at 

 the root of the neck in the innominate vein. The vertebral vein accomi)anies the 

 vertelrral artery through the foramina in the transverse processes of the cervical 

 vertebrie. It begins in the suboccipital triangle by the confluence of small veins 

 from the deep muscles at the ])ack of the occiput, and, after receiving tributaries 

 from the cervical spine and deep muscles of the neck, ends in the innominate 

 vein. The deep cervical receives the occii)ital vein, courses downwards amongst the 

 deep muscles at the Imck of the neck, and ends in the iminminate vein. 



THE SUPERFICIAL VEINS OF THE HEAD AND NECK 



1. THE SUPERFICIAL VEINS OF THE SCALP AND FACE 



The blood from the scalp is returne(l by three main channels — viz. an anterior, 

 which passes over the forehead and face; a posterior, which descends over the 

 occipital l)one; and a lateral, formed ])y the confluence of two smaller veins which 

 descend over the parietal and temporal bones respectively — one in front, and one 

 behind the ear. 



