CHAPTER IV 

 VASCULAR SYSTEM 



ARTERIAL SYSTEM. (Plate V.) 



The Aorta is the large blood-vessel which leaves 

 the left ventricle of the heart and bends in an arch 

 to the left and passes posteriorly along the mid- 

 line. It gives ofT the following branches : 



i . The Brachio-cephalic or Innominate Artery is the 

 first and larger of the two branches which lead 

 anteriorly from the arch of the aorta. It soon 

 gives off the following : 



a. The Right and Left Carotid Arteries. These 

 pass anteriorly along either side of the trachea 

 and are distributed to the neck and head. Their 

 principal branches are : 



(1) The Thyroid Artery, given off at the level of 

 the thyroid gland, and distributed principally to 

 that organ. 



(2) A large Muscular Branch, given off directly 

 opposite the thyroid artery, which supplies the 

 muscles of the neck. 



(3) The Lingual Artery, which is distributed to 

 the under surface of the tongue. 



(4) The Facial Artery, which sends branches to 



