456 ANGIOLOGY. 



oesophagus. The efferent vessels unite to form two or three 

 trunks which enter the thoracic duct in different places. 



THOKACIC WALLS. 



In this group there are also three sets ; a double chain of small 

 round glands, situated on each side of the dorsal vertebrae above 

 the intercostal spaces, and under the costal pleura ; a large gland- 

 ular mass, resting on the xiphoid cartilage, just behind the heart 

 and in front of the inferior part of the diaphragm ; and a group 

 of rudimentary glands, which accompany the internal thoracic 

 arteries. 



The lymphatics of the diaphragm, after receiving, it is said, 

 those from the convex face of the liver, enter the glands at the 

 base of the diaphragm, leaving them by numerous branches which 

 accompany the internal thoracic arteries, and either join the 

 anterior extremity of the thoracic duct or the great lymphatic 

 vein, usuallji' after passing through the prepectoral glands. They 

 receive the lymphatics from the inferior part of the intercostal 

 spaces. The other lymphatic vessels of the thoracic walls run 

 upwards in the intercostal spaces, and enter the chain of glands 

 along the sides of the dorsal vertebrae, forming two canals, which 

 pass forwards to enter the anterior portion of the thoracic duct. 



ANTERIOR REGION. 



The lymphatics of the head, neck, and anterior extremity are 

 directed to the entrance of the thorax, where there is a group of 

 glands termed the iJrepectoral, which may be regarded as the 

 lymphatic centre of the whole anterior, as the suhlumbar is of 

 the posterior part of the body. Before the vessels reach this 

 point of convergence, they are intercepted by one or more of four 

 other glandular groups. We have in this region the following 

 groups of glands : — 



Prepectoral. I Submaxillary. 



Guttural. | Prescapular. 



Brachial. 



The prepectoral glands are found on each side of the ter- 

 minal extremity of the jugular veins, inside the inferior border of 

 the scalenus ; they are massive, passing into the chest under the 

 brachial vessels, and along the internal aspect of the first pair of 



