1058 THE ORGANS OF DIGESTION. 



diaphragm in the falciform ligament. They ramify in the lobes adjoining the 

 ligament. They are almost capillary and anastomose with each other. 



The fifth group is formed of veins passing from the sub umbilical part of the 

 abdominal wall to the left longitudinal fissure of the liver. They are situated in 

 the inferior part of the falciform ligament. The most important end at the umbili- 

 cal incisure of the liver ; others end in the umbilical fissure ; and others, very deli- 

 cate, surround the round ligament : one or two constantly empty into the left portal 

 branch. At their origin these veins communicate with the epigastric veins, inter- 

 nal mammary, and the tegumentary veins of the abdomen. 



The fourth and fifth groups do not come from the alimentary tract, and hence 

 establish an anastomosis between the portal and general venous systems. These 

 branches would dilate in some chronic diseases of the liver and aid the obstructed 

 portal system. 



The hepatic duct is formed at the transverse fissure by two tributaries, one 

 from the right and one from the left lobe. The calibre of each nearly equals that 

 of the trunk formed. The tributaries to these two branches start from the inter- 

 lobular spaces in company with the portal and arterial twigs. 



The lymph-vessels form a superficial and deep set. 



The superficial lymph-vessels of the convex surface belong either to the poste- 

 rior half or to the anterior half of the liver. Those of the posterior half form 

 several groups, and from right to left are found first on the right edge, a larger 

 lymph-vessel which runs around to the right lateral ligament, and from there to 

 the inferior surface, and empties into a gland on the head of the pancreas. 



Then comes a series of lymph-vessels which go over to the coronary ligament, 

 and from there to the posterior surface of the liver, and empty into the lymphatic 

 glands which lie on the inferior vena cava just above the Diaphragm. Along the 

 falciform ligament from the right as well as from the left lobe is developed a rich 

 network of vessels which unite into several larger trunks. These run between 

 both layers of the falciform ligament, and join finally to form a big trunk which 

 pierces the Diaphragm and empties into glands situated above this at its point of 

 fusion with the pericardium. 



Those vessels springing more laterally from the left lobe of the liver empty 

 into glands situated more to the right, lying on the vena cava ; the vessels rising 

 to the left of the left lateral ligament, and from it, empty into glands situated on 

 the lower part of the oesophagus. 



Those vessels springing from the anterior half of the convex surface arch 

 around the anterior margin of the liver and run into the glands situated in the 

 transverse fissure. The vessels of the under surface also pass to those same 

 glands. Only a few twigs arising on the posterior surface of the liver end in the 

 glands lying on the vena cava. 



Of the deeper lymph-vessels, some accompany the portal veins, and others the 

 hepatic veins. The first, fifteen or eighteen in number, empty into the glands sur- 

 rounding the neck of the gall-bladder. The last accompany the hepatic veins to 

 the vena cava, five or six in number, and pass through the foramen venae cavae of 

 the Diaphragm, and empty into glands situated just above it. 



Microscopically the lymphatics are seen in Glisson's capsule in the interlobular 

 spaces, where they accompany the blood-vessels. They rise from lymph-spaces in 

 the intralobular plexus. 



The nerves come from two sources, left vagus and coeliac plexus. The left 

 vagus after its passage through the oesophageal opening gives off twigs which turn 

 from left to right along the lesser curvature of the stomach, between the two layers 

 of the lesser omentum, to accompany the branches of the portal veins. Those 

 twigs from the coeliac plexus are much more numerous, and come from three 

 sources, right vagus, phrenic, and great sympathetic. They meet the hepatic 

 artery and follow this to the transverse fissure. The nerves all divide into right 

 and left sets, which accompany the branches of the artery, of the portal vein, and 

 the tributaries of the hepatic duct. They terminate in fine tree-like endings, show- 



