VEINS. 



each, arising early, runs backward between the necks of the 

 ribs, sending a spinal branch through the inter vertebral fora- 

 men, and dividing in the vertebral groove into internal and 

 external branches. Subcostal: This pair resembles the in- 

 tercostals; one runs along the lower border of the twelfth rib 

 on each side, between the Transversalis and Internal oblique. 

 Diaphragmatic : to the upper surface of the Diaphragm. Fas 

 aberrans: This inconstant branch arises high up, from the 

 front and right side, and ascends behind the oesophagus. 

 Bronchial : There are usually but two, upper and lower, both 

 on the left side and going to the left lung. The right bronchial 

 artery may arise from the upper of these, from the first right 

 aortic intercostal, or from the aorta itself . (Esophageal: four 

 or five small branches to the oesophagus. Pericardial : small 

 branches to the pericardium. Mediastinal: small branches 

 to the posterior mediastinum. [837] 



VEINS. 



Pulmonary Veins. There are two on each side, upper and 

 lower. The upper right vein drains the right upper and middle 

 lobes ; the others each drain one lobe. In the root of each lung, 

 the upper vein lies below and in front of the artery ; the lower 

 vein is at the lowest part. The right upper vein runs behind 

 the superior vena cava, and the lower vein behind the right 

 auricle. Both left veins run in front of the aorta. All enter 

 the upper and back part of the left auricle. [870] 



Cardiac Veins. The coronary sinus lies in the auriculo- ven- 

 tricular sulcus, on the left side, and ends in the right auricle. 

 Its tributaries are: left coronary vein (great cardiac), running 

 in the anterior interventricular and auriculo-ventricular sulci 

 to the left end of the sinus and receiving a vein (left marginal) 

 from the left margin; right coronary vein (small cardiac) run- 

 ning in the auriculo-ventricular sulcus, entering the right end 

 of the sinus and receiving a vein (right marginal) from the 

 right margin ; oblique vein of Marshall, descending on the back 



[133] 



