THE VEINS OF THE HEAD AND NECK 



643 



3. The Middle Cardiac Vein (v. cordis media) commences at the apex of the heart, 

 ascends in the posterior longitudinal sulcus, and ends in the coronary sinus near 

 its right extremity. 



!4. The Posterior Vein of the Left Ventricle (v. posterior ventriculi sinistri) runs on 

 the diaphragmatic surface of the left ventricle to the coronary sinus, but may end 

 in the great cardiac vein. 



5. The Oblique Vein of the Left Atrium (v. obliqua atrii sinistri [Marshalli] ; oblique 

 vein of Marshall) is a small vessel which descends obliquely on the back of the left 

 atrium and ends in the coronary sinus near its left extremity; it is continuous above 

 with the ligament of the left vena cava (lig. vence cavoe sinistrce; vestigial fold of 

 Marshall), and the two structures form the remnant of the left Cuvierian duct. 



Azygos vein 



Left pulmonary veins 



Oblique vein of left atrium 

 Great cardiac vein 

 Left marginal vein 



Bight pulmonary 

 veins 



Small cardiac vein 



.^^^ 

 Posterior vein of left ventricle 



Middle cardiac vein 

 FIG. 556. Base and diaphragmatic surface of heart. 



The following cardiac veins do not end in the coronary sinus: (1) the anterior 

 cardiac veins, comprising three or four small vessels which collect blood from the 

 front of the right ventricle and open into the right atrium ; the right marginal vein 

 frequently opens into the right atrium, and is therefore sometimes regarded as 

 belonging to this group; (2) the smallest cardiac veins (veins of Thebesius), con- 

 sisting of a number of minute veins which arise in the muscular wall of the heart; 

 the majority open into the atria, but a few end in the ventricles. 



THE VEINS OF THE HEAD AND NECK. 



The veins of the head and neck may be subdivided into three groups: (1) The 

 veins of the exterior of the head and face. (2) The veins of the neck. (3) The diploic 

 veins, the veins of the brain, and the venous sinuses of the dura mater. 



