134 LYMPHATIC SYSTEM. 



tion of the large trunk of the lacteals, as seen at m Plate II. 

 The thoracic duct therefore is the common trunk which receives 

 the lymphatic vessels of the lower extremities, the lacteals, and 

 the lymphatics of all the abdominal viscera. 



With respect to the lymphatics of the larger viscera, (such 

 as the liver, the spleen, and the kidneys,) they are generally 

 in two sets : one which lies upon the surface of the organ, and 

 the other which accompanies the large blood-vessels in its centre. 

 In the liver I have found these two sets communicate with 

 each other, so that by injecting mercury into the lymphatic 

 vessels which lie upon its convex surface, I have filled those 

 which accompany the pori bilarii and vena portarum in its 

 centre. The greatest part of the lymphatic vessels which lie 

 upon the convex surface of the liver, run towards its falciform 

 ligament, and pass down by the side of the vena cava. But 

 some of them run towards the right ligament of the liver, 

 where they pass down upon the diaphragm to get to the tho- 

 racic duct. The lymphatics on the concave surface run towards 

 the portae where they join those which come from the centre 

 of the liver along with its large blood-vessels ; it is remarkable 

 of those lymphatic vessels which run upon the surface of the 

 liver, that their valves can readily be made to give way, so 

 that I have injected them from their trunks to their branches, 

 and to great minuteness ; some preparations of which I have 

 now by me. 



It has been suggested by one of the best anatomists of this 

 age, 1 that the lymphatics of the stomach do not open into the 

 thoracic duct like those of the other viscera, but only open into 

 the sanguiferous veins of the stomach ; but from repeated dis- 

 sections of the human subject I am convinced of the contrary ; 

 and likewise from the analogy with other animals, particularly 

 fish, whose lymphatic vessels either have no valves, or the 

 valves readily give way, so that I have repeatedly pushed in- 

 jections from the thoracic duct into the lymphatics of their 

 stomachs, as I have also done into the lymphatics of the other 

 viscera contained in the cavity of their abdomen; as will be 

 more particularly mentioned hereafter. 



The thoracic duct, which receives all the vessels that we 

 have yet described, differs in its size in different subjects, but 



1 Dr. Meckel. 



