DISSECTION OF THE THORAX 409 



On left side. 



(a) Arch of aorta (arcus aortae). 



(b) Descending aorta (aorta descendens). 



The student should next undertake the dissection of the 

 structures in the root of each lung. Isolate them in the following 

 order : 



(a) Anterior pulmonary plexus (plexus pulmonalis anterior}. 



(b) Posterior pulmonary plexus (plexus pulmonalis posterior). 



To expose this, throw the lung medial ward over the pericardium 

 and remove the pleura from the back part of the radix pulmonis. 

 Secure the N. vagus and follow it into the plexus. 



(c) Bronchial arteries ( Aa. bronchioles), from the aorta thoracalis. 



(d) Pulmonary artery (A. pulmonalis). 



(da) Right ramus (ramus dexter). 



(db) Left ramus (ramus sinister). 



(e) Pulmonary veins (venae pulmonales). 



(ea) Right pulmonary veins (Vv. pulmonales dextrae). 



(eb) Left pulmonary veins (Vv. pulmonales sinistrae). 



(f) Bronchus, right and left (bronchus [dexter et sinister]). 



(fa) Bronchial rami (rami bronchiales) . (Vide Fig. 216.) 



(faa) Eparterial ramus (ramus bronchialis eparterialis) . 



(fab) Hyparterial rami (rami bronchiales hyparteriales). 



(g) Bronchial lymph-glands (lymphoglandulae bronchiales). 



Isolate these parts thoroughly and clean each structure; it 

 may be necessary to remove the bronchial lymph-glands in order 

 to expose the vessels and bronchi adequately. Fix in the memory 

 the relations of bronchus, artery, and vein, from before back- 

 ward and from above downward, on each side. 



Phrenic Nerve and Cardiac Plexus (N. phrenicus and plexus car- 



diacus). 



The phrenic nerve should be followed upward and downward 

 on each side, and the differences in relations on the two sides 

 studied. Isolate the following branches of the N. phrenicus : 



(a) Pericardiac ramus (ramus pericardiacus) . 



(b) Phrenico-abdominal rami (rami phrenicoabdominales). 



In dissecting out the cardiac plexus of nerves (plexus car- 

 diacus) in the concavity of the aortic arch, follow down 



(a) Superior cardiac nerve (N. cardiacus superior), from the cervical 



sympathetic. 



(b) Inferior cardiac ramus (ramus cardiacus inferior), from the left N. 



vagus. 



