358 A MANUAL OF ANATOMY. 



right bronchus presents a more conspicuous opening than 

 the left, and therefore is more liable to receive any object 

 inspired into the trachea. 



The right bronchus gives off a large branch to the upper 

 lobe of the lung and then bifurcates to supply the middle 

 and lower lobes. 



The left bronchus divides into two branches, one for each 

 lobe. 



The right bronchus is shorter, wider, and more hori- 

 zontal than the left. Its length is about an inch and its 

 width a little more than half as much. The right pul- 

 monary artery is below and then in front of the bronchus. 

 The azygos major vein arches upward over the bronchus 

 from behind to empty into the vena cava superior. 



The left bronchus is longer, narrower, and more oblique 

 than the right. Its length is about two inches. In front 

 of it is the aortic arch, the left pulmonary artery is above 

 and then in front of it. Behind the bronchus is the 

 oesophagus, thoracic duct, and descending aorta. 



The Lungs. Figs. 59, 68. 



The lungs are two in number, the right and left. The 

 right consists of three lobes and the left of two. 



When the chest is intact they fill the pleural cavities, 

 with the exception of the extreme lower angle between the 

 chest and diaphragm. See page 263. The lung is de- 

 scribed as having an apex, projecting into the root of the 

 neck through the upper opening of the chest, and rising 

 above the first rib about one and one-half inches (three- 

 fourths of an inch above the clavicle) ; a base, concave, to 

 fit over the convexity of the diaphragm, upon which it 

 rests ; an outer convex surface opposed to the interior of 

 the chest ; an inner surface, concave, fitting over the peri- 



