496 



THE ABSORBENTS. 



them occupy the interval between the right and left bronchi at their diver- 

 gence, whilst others of smaller size rest upon the first divisions of these tubes 



Fig. 336. 



Fig. 336. LYMPHATIC VES- 

 SELS OF TUB HEAD AND 

 NECK AND OP THE UPPER 

 PART OP THE TRUNK 

 (from Mascagni). 



The chest and pericar- 

 dium have been opened on 

 the left side, and the left 

 mamma detached and 

 thrown outwards over the 

 left arm, so as to expose a 

 great part of its deep sur- 

 face. 



The principal lymphatic 

 vessels and glands are shown 

 on the side of the head and 

 face, and in the neck, axilla, 

 and mediastinum. Between 

 the left internal jugular vein 

 and the common carotid 

 artery, the upper ascending 

 part of the thoracic duct 

 marked 1, and above this, 

 and descending to 2, the 

 arch and last part of the 

 duct. The termination of 

 the upper lymphatics of 

 the diaphragm in the me- 

 diastinal glands, as well as 

 the cardiac and the deep 

 mammary lymphatics, are 

 also shown. 



for a short distance 

 within the lungs. In 

 early infancy their co- 

 lour is pale red ; towards puberty, we find them verging to grey, and studded 

 with dark spots ; at a more advanced age they are frequently very dark or 

 almost black. In chronic diseases of the lungs they sometimes become en- 

 larged and indurated, so as to press on the air tubes and cause much irrita- 

 tion. They are frequently the seat of tuberculous deposits. 



The deep lymphatics of the thoracic walls are divisible into two sets, the 

 sternal and the intercostal. The sternal lymphatics, commencing in the 

 muscles of the abdomen, ascend between the fibres of the diaphragm at its 

 attachment to the ensiform cartilage, and continue upwards behind the 

 costal cartilages to terminate on the left side in the thoracic duct, and on 

 the opposite side in the right lymphatic duct. They receive branches from 

 the upper surface of the liver, and small branches from the anterior parts of 

 the intercostal spaces. The intercostal lymphatics, passing backwards in 

 each intercostal space, receive, as they approach the spine, branches 

 coming forward through the intertransverse space, and enter the intercostal 

 glands, through the efferent ducts of which their contents are poured on 

 both sides of the body into the thoracic duct. 



The lymphatics of the lungs, like those of other organs, form two sets, 

 one being superficial, the other deep-seated. Those at the surface run 

 beneath the pleura, where they form a network by their anastomoses. 



