282 



THE CIRCULATORY SYSTEM. 



2. A. anonyma (Fig. 115,7; Fi g- Il8 > ^)- The innominate 

 artery passes craniad from the convexity of the aortic arch (a'). 

 It gives rise first to a small mediastinal artery (in) which 



passes ventrad into the mediastinum, then to the left common 

 carotid (Fig. 115, /), then to the right common carotid (Fig. 

 115, m). Sometimes the carotids are given off from a common 

 trunk. Beyond the right common carotid the innominate is 

 continued as the right subclavian (Fig. 115, n). 



