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SUBCL AVIAN ARTERY. RELATIONS. 



and phrenic nerve. Behind and beneath it is invested by the pleura, 

 is crossed by the right recurrent laryngeal nerve and vertebral vein, 

 and is in relation with the transverse process of the seventh cervical 

 vertebra. The^rr^ portion on the left side is in relation in front with 

 the pleura, the vena innominata, the pneumogastric and phrenic nerves 

 (which lie parallel to it), and the left carotid artery. To its inner 

 side is the ossophagus ; to its outer side the pleura ; and behind, the 

 thoracic duct, longus colli, and vertebral column. 



Plan of the relations of ike first portion of the Right Subclavian Artery. 



In Front. 



Internal jugular vein, 

 Subclavian vein, 

 Pneumogastric nerve, 

 Cardiac nerves, 

 Phrenic nerve. 



Right Subclavian Artery. 



Behind and Beneath. 



Pleura, 

 Recurrent laryngeal nerve, 



Vertebral vein, 

 Transverse process of 7th cervical vertebra. 



Plan of the relations of the first portion of the Left Subclavian 

 Artery. 



In Front. 

 Pleura, 



Vena innominata, 

 Pneumogastric nerve, 

 Phrenic nerve, 

 Left carotid artery. 



Inner Side. 

 (Esophagus 



Left subclavian artery. 



Outer Side. 

 Pleura. 



Behind. 



Thoracic duct, 

 Longus colli, 

 Vertebral column. 



The Second portion is situated between the two scaleni, and is sup- 

 ported by the margin of the first rib. The scalenus anticus separates 

 it from the subclavian vein and phrenic nerve. Behind it is in rela- 

 tion with the brachial plexus. 



The TJiird portion is in relation, in front with the subclavian vein 



