724 THE LYMPHATICS IN PARTICULAR. 



united into a single vessel, into which the third opens at a variable distance from 

 the confluent of the first." ^ 



The affluents of the thoracic ditct. — The lymphatic vessels which enter the 

 thoracic duct are as remarkable for their number as their volume. Some empty 

 themselves into the receptaculum chyli ; a few vessels open into the great 

 lymphatic vessel of the thorax, and the others terminate in that canal near its 

 entrance into the venous system. 



The first, variable in their number — particularly the largest — are more espe- 

 cially regarded as the roots of the thoracic duct. 



Ordinarily three are found, with a certain number of small accessory trunks. 

 One of the largest branches enters the posterior part of the receptaculum chyli. 

 Very often double, and even multiple, it arises from an enormous group of glands 

 in the sublumbar region, around the posterior extremity of the abdominal aorta 

 and vena cava, and into which are collected all the vessels of the posterior limbs, 

 the pelvis, abdominal walls, and the pelvi-inguinal viscera. The other two trunks 

 reach the left side of the receptaculum, and result from the union of the lym- 

 phatics which come from the abdominal digestive organs ; among these 

 lymphatics, however, there are some belonging to the parietes of the stomach 

 and the parenchyma of the liver and spleen, and which reach the right side of 

 the receptaculum, to open singly into that cavity. 



The affluents the thoracic duct receives on its course, proceed from the viscera 

 contained in the thoracic cavity, and from the walls of that cavity. 



Those which terminate at the anterior extremity of the duct are formed by 

 the lymphatics of the left anterior limb, and the left half of the thorax, 

 diaphragm, neck, and head. 



We will now examine rapidly all the radicles of these affluents. 



Aeticle II. — The Lymphatics which form the Affluents of the 



Thoracic Duct. 



These lymphatic vessels are divided into five groups : 1. Those of the 

 abdominal limb, the pelvis, the abdominal parietes, and the pelvi-inguinal organs. 

 2. Those of the abdominal digestive viscera. 3. Those of the organs contained 

 in the chest. 4. Those of the thorax. 5. Those of the head, neck, and anterior 

 limb. 



Lymphatics of the Abdominal Limb, Pelvis, Abdominal Parietes, 

 and the Pelvi-inguinal Organs. 



All these vessels converge towards an immense group of glands — the suh' 

 lumbar. Besides these, there are other groups on difi:erent parts of their course, 

 constituting the deep inguinal, superficial inguinal, popliteal, iliac, and precrural 

 glands. The successive description of these glands, and their afferent and 

 efferent vessels, will complete the study of this apparatus. 



1. Sublumbar Glands (Fig. 399). 



This group, which occupies, as its name indicates, the sublumbar region, 

 comprises : 1. A small single mass situated in the sinus of the angle formed by 

 the two internal iliac arteries, and is often only a single large gland. 2. Another 



' G. Colin, Traitede Physiologie Compar^e des Animaux Domediques, 'Zod Edition, vol. ii 

 Paris: 1871. 



