CHAPTEE XIII. 



DISEASES OF THE LYMPHATIC SYSTEM. 



LYMPHATIC VESSELS. 



Lymphangitis. It is only in the superficial lymphatic vessels 

 of the subcutaneous tissue that evidence of inflammation can be 

 discerned by the eye. These when inflamed appear as red 

 streaks owing to the peri-lymphangitis which accompanies the 

 affection. In some instances the distribution of the lymphatic 

 vessels is thus clearly marked out, and the skin then becomes 

 mapped with a fine network of reddened lymphatics. Owing to 

 their proximity to the surface, an induration caused by the 

 inflammatory products can occasionally be readily palpated, 

 and is very characteristic. Because of the same anatomical 

 relation, lymphorrhoea is seen from the ulcerations and fissures 

 of portions of skin affected with filarial and other obstruction 

 of the lymphatics. 



The deep lymphatic vessels of the limbs commence in the 

 bones, periosteum, ligaments, muscles and inter-muscular con- 

 nective tissue, altogether beneath the deep fascia. It is on 

 this account that inflammation of these vessels seldom gives 

 evidence of its existence by signs superficial to the deep 

 fascia, as is well observed in the early stages of acute infective 

 periostitis. 



The deep lymphatics within the abdomen, especially those 

 running between the layers of the mesentery and omenta, are 

 but little supported, and when there is any obstruction to the 

 onward flow of lymph in them easily part with their contents to 

 form an effusion in the peritoneal cavity, in the form of chylous 

 ascites. 



Where lymphatics lie in loose connective tissue, as for example 



