THE LIVER. 



1063 



the biliary ducts ; they have a yellowish color, have epithelial lining, and fibrous 

 coat, and in proportion as the lobe has atrophied, they have hypertrophied. They 

 present the tubular recesses, and anastomose with each other. These vessels are 

 found in certain mammals. 



The Excretory Apparatus of the Liver. This apparatus consists of the bile- 

 canaliculi and ducts, which we have seen in and between the lobules; of the hepatic 

 duct formed by the union of these ; of a diverticuluin or reservoir the (/all-bladder ; 

 of the communicating tube, cystic duct, and of the united cystic and hepatic ducts, 

 the common bile-duct or ductus choledochus (Fig. 677). 



Gall-bladder 



Hepatic duct 



Common bile-duct 



Duodenal 

 orifice 



FIG. 677. Biliary vessels and gall-bladder, dried and insufflated. (Tillaux.) 



The hepatic duct is formed by the union of the right and left bile -ducts 

 descending from the liver. They unite at an obtuse angle at the right end of the 

 transverse fissure. Their point of union is usually near the spot where they 

 emerge from the liver. Often this happens lower down and the hepatic duct is 

 shortened. Its usual length is 3-5 cm. (one to two inches) and diameter 4 mm. 

 It joins with the cystic duct at an acute angle to form the common bile-duct. It 

 descends in the right margin of the gastro-hepatic onientum with the vena cava 

 behind and the hepatic artery to the left. The passage of bile into the gall-bladder 

 only occurs when its exit to the duodenum is closed. The bile then from the 

 beginning of the common duct has a passage provided upward and backward to a 

 reservoir which is the gall-bladder. 



