STRUCTURE OF THE LIVER 



385 



is conveyed from it by the hepatic duct, either directly into the intestine or 

 when digestion is not going on, into the cystic duct, and thence into the gall- 

 bladder, where it accumulates until required. The portal vein, hepatic 

 artery, and hepatic duct branch together throughout the liver, while the 

 hepatic veins and their tributaries run by themselves. The interstices of the 

 vessels are filled by the liver cells. 



Structure of the Liver. The liver is made up of small roundish or 

 oval portions called lobules, each of which is about ^ of an inch (about 



P x 



FIG. 272. Section of Liver. X 80. P, Portal vein; H, hepatic artery; B, bile-duct. 



(Hendrickson.) 



i mm.) in diameter, and includes the minute hepatic artery and hepatic 

 duct. The hepatic cells, which form the glandular or secreting part of the 

 liver, are of spheroidal form, somewhat polygonal from mutual pressure, 

 about 25 to 3o// in diameter, and possess one, sometimes two nuclei. The 

 cell substance contains a variable amount of glycogen and often some fatty 

 globules and possibly some granules of bile pigment. 



The bile capillaries commence between the hepatic cells, and are bounded 

 by a delicate membranous wall of their own. They appear to be always 

 bounded by hepatic cells on all sides, and are thus separated from the nearest 

 blood capillary by at least the breadth of one cell, figures 271 and 272. 



