THE LIVER 



Gall- 

 bladder 



the sinusoids empty themselves into one vein, of considerable size, which runs down the 

 center of the lobule from apex to base, and is called the intralobular vein. At the base of 

 the lobule this vein opens directly into the sublobular vein, with which the lobule is con- 

 nected. The sublobular veins unite to form larger and larger trunks, and end at last in the 

 hepatic veins, these converge to form three large trunks which open into the inferior vena cava 

 while that vessel is situated in its fossa on the posterior surface of the liver. 



3. The bile ducts commence by little passages in the liver cells which communicate with 

 canaliculi termed intercellular biliary passages (bile capillaries'). These passages are merely 

 little channels or spaces left between the contiguous surfaces of two cells, or in the angle where 

 three or more liver cells meet (Fig. 1094), and they are always separated from the blood capil- 

 laries by at least half the width of a liver cell. The channels thus formed radiate to the circum- 

 ference of the lobule, and open into the interlobular bile ducts which run in Glisson's capsule, 

 accompanying the portal vein and hepatic artery (Fig. 1093). These join with other ducts to 

 form two main trunks, which leave the liver at the transverse fissure, and by their union form 

 the hepatic duct. 



Structure of the Ducts. The walls of the biliary ducts consist of a connective-tissue coat, in 

 which are muscle cells, arranged both circularly and longitudinally, and an epithelial layer, 

 consisting of short columnar cells resting on a distinct basement membrane. 



Excretory Apparatus of the Liver. The excretory apparatus of the liver con- 

 sists of (1) the hepatic duct, formed by the junction of the two main ducts, which 

 pass out of the liver at the porta; (2) the gall- 

 bladder, which serves as a reservoir for the bile; 

 (3) the cystic duct, or the duct of the gall-blad- 

 der; and (4) the common bile duct, formed by 

 the junction of the hepatic and cystic ducts 



The Hepatic Duct (ductus hepaticus) . Two 

 main trunks of nearly equal size issue from 

 the liver at the porta, one from the right, the 

 other from the left lobe; these unite to form 

 the hepatic duct, which passes downward and 

 to the right for about 4 cm., between the layers 

 of the lesser omentum, where it is joined at 

 an acute angle by the cystic duct, and so forms 

 the common bile duct. The hepatic duct is 

 accompanied by the hepatic artery and portal 

 vein. 



The Gall-bladder (cesica fellea) (Fig. 1095). 

 The gall-bladder is a conical or pear-shaped 

 musculomembranoiis sac, lodged in a fossa on 

 the under surface of the right lobe of the liver, 

 and extending from near the right extremity of 

 the porta to the anterior border of the organ. It 

 is from 7 to 10 cm. in length, 2.5 cm. in breadth at 

 its widest part, and holds from 30 to 35 c.c. It is 

 divided into a fundus, body, and neck. The 

 fundus, or broad extremity, is directed down- 

 ward, forward, and to the right, and projects 

 beyond the anterior border of the liver; the 

 body and neck are directed upward and back- 

 ward to the left. The upper surface of the gall- 

 bladder is attached to the liver by connective 

 tissue and vessels. The under surface is covered by peritoneum, which is reflected 

 on to it from the surface of the liver. Occasionally the whole of the organ is 

 invested by the serous membrane, and is then connected to the liver by a kind 

 of mesentery. 



Relations. The body is in relation, by its upper surface, with the liver; by its under surface, 

 with the commencement of the transverse colon; and farther back usually with the upper end 



Hepatic 

 duct 



Common bile* 

 duct 



FIG. 1095. The gall-bladder and bile ducts 

 laid open. (Spalteholz.) 



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