Chap. X.] 



THE HEART AND CIRCULATION. 



205 



the left side, and represents the pulmonary arch of that side 

 only. It soon bifurcates to supply the two lungs of which the 

 right is removed in the figure. From the lungs the blood is 

 returned by the pulmonary veins (pul. v.) to the left auricle 

 (L au.). Thence it passes into the left ventricle (I. v.). From 



pt.r. 



Fio. 63. HEART AND GREAT VESSELS RABBIT. 



a. i. c. v. Anterior intercostal vein. ao. Aorta, ao. ar. Aortic arch. 

 az. v. Azygos vein. ex. ju. External jugular vein. in. a. Innominate artery. 

 in.ju. Internal jugular vein. 1. OM. Left auricle. I. c. c. Left common 

 carotid artery. I. pr. c. Left precaval vein. L v. Left ventricle, pt. c. Post- 

 caval vein. pul. a. Pulmonary artery, pul. v. Pulmonary vessels: r. au. Right 

 auricle. r. c. c. Right common carotid artery, r. v. Right ventricle. 

 s. cl. a. Subclavian artery, s. d. v. Subclavian vein. s. d. Subclavian artery 

 and vein of the right side. 



this chamber it passes by the single aortic arch (ao. ar.) (which 

 answers to the left systemic aorta of the frog). At the summit 

 of the arch arises a vessel which at once bifurcates, giving rise to 

 the left common carotid (1. c. c.) and the innominate (in. a), which 

 latter soon again bifurcates to form the right common carotid 

 (r. c. c. ) and the right subclavian artery. The left subclavian artery 

 (s. cl. a.) takes its origin from the aortic arch independently. 



