62 



THORAX 



and divides into a descending or interventricular, and a 

 circumflex branch. The interventricular branch passes down 

 the sterno-costal surface of the heart, in the anterior longitudinal 

 sulcus (Fig. 29), and turning round the lower border, in the 

 cardiac notch, it anastomoses with the interventricular branch 



Right 



innominate vein 

 Innominate artery 



Superior vena c 



Serous . 

 pericardium' 



Apex of right auricle 

 (O.T. appendix) 



Coronary 

 sulcus 



Marginal branch 

 of right corona 

 artery 



Right ventricle 



Left common carotid 

 Left subclavian 



Left innominate vein 



Aortic arch 

 Ligamentum arteriosum 



Left pulmonary artery 

 -Pulmonary artery 



Left auricle (O.T. appendix) 

 Conus arteriosus 



Anterior interven- 

 tricular furrow with 

 the interventricular 

 branch of the left coro- 

 nary artery and the 

 great cardiac vein 



Left ventricle 



Apex of heart 



FIG. 29. Sterno-costal Surface of the Heart. 



of the right coronary artery. The circumflex branch runs to 

 the left, in the coronary sulcus, turns round the left border 

 of the heart (Fig. 28) and anastomoses, on the posterior 

 surface, with the transverse terminal branch of the right 

 coronary. From the stem of the artery twigs are given to 

 the roots of the pulmonary artery and the aorta, and its 

 terminal branches supply the walls of both ventricles and the 

 walls of the left atrium. 



Venae Cordis. The cardiac veins are: (i) the coronary 



