THE THORAX AND THORACIC VISCERA. 79 



Expose the remains of the thymus gland, then clear it away. Demonstrate the superficial cardiac 

 plexus and trace the superior and inferior cervical cardiac nerves of the left side. Carefully dissect 

 away the pericardium, fat, connective tissue and fascia from the base of the heart. Expose the supe- 

 rior vena cava and its tributaries, also the arch of the aorta and its branches. 



The thymus body or gland, 955-6-7. (935-6) 

 Relations. 

 Structure. 

 Vessels : Arteries. 



Veins. 

 Nerves. 



Lymphatics of the thymus, 697. (682) 

 Superficial cardiac plexus, 869-70. (849) 



Superior cervical cardiac nerve, left side, 867. (847) 

 Inferior cervical cardiac nerve of the left side, 819. (800) 

 The veins, 638. (626) 

 Pulmonary. 

 Systemic. 



Veins of the thorax. 



Innominate, or brachio-cephalic veins, 640-1. (627-8) 

 Right innominate vein : 

 Relations : In front. 

 Behind. 

 Right. 

 Left. 



Left innominate vein : 

 Relations : In front. 

 Behind. 

 Below. 

 Above. 

 Tributaries : 



Internal mammary veins. 

 Left superior intercostal vein. 

 Mediastinal, pericardial, and thymic veins. 

 Superior or descending vena cava, 639. (627) 

 Relations : In front. 

 Behind. 

 Right side. 

 Left side. 

 Tributaries. 



Chief variations in the superior vena cava and innominate veins, 642. (628-9-30) 

 (y) Variations due to the persistence of the left duct of Cuvier. 

 (2) Variations due to persistence of the left and suppression of the right duct 



of Cuvier. 



The aorta, 495 to 501. (487 to 494) 

 Arch of the aorta. Thoracic aorta. 

 Arch of the aorta : 



Ascending portion of the arch : 

 Relations: In front. 

 Behind. 

 Right side. 

 Left side. 



Transverse portion of the arch : 

 Relations : In front. 

 Behind. 

 Above. 

 Below. 



Descending portion of the arch : 

 Relations : In front. 

 Behind. 



