350 



DISSECTION OF THE ABDOMEN. 



and supplii 

 branches ; 



receives 

 vaginal 

 branches. 



Hepatic 

 artery 

 nourishes 

 the vessels 

 and capsule : 



ending in 

 lobules. 



and end in 

 the vena 

 cava. 



Biliary 

 ducts form 



right, left, 

 and common 

 hepatic 

 ducts. 



Structure 

 of medium- 

 sized ducts. 



until the last branches of the vein (interlobular) penetrate between 

 the lobules, where they communicate together, and supply the 

 hepatic substance. 



In the portal canals the offsets of the vena portae are joined by 

 small vaginal and capsular veins, which convey blood from branches 

 of the hepatic artery. 



The hepatic artery (tig. 132, c), while surrounded by the capsule, 

 furnishes vaginal branches, which ramify in the sheath, giving it a 

 red appearance in a well-injected liver, and supply twigs to the 

 coats of the portal vein and biliary ducts, and to the areolar tissue : 

 from the vaginal branches a few offsets (capsular) are given to the 



coat of the liver. Finally, the 

 artery ends in fine interlobular 

 branches, from which offsets 

 enter the lobules. 



The hepatic veins (venae cavae 

 hepaticae) begin by small intra- 

 lobular veins from the centre of 

 the lobules ; these are received 

 into the sublobular branches, 

 which anastomose together, and 

 unite into larger vessels. Fin- 

 ally, uniting with neighbouring 

 branches to produce larger 

 trunks, the hepatic veins are 

 directed from before backwards 

 to the vena cava inferior, into 

 which they open by large ori- 

 fices. The hepatic veins may be 

 said to be without a sheath, 

 except in the larger trunks ; so 

 that when they are cut across 

 the ends remain patent, in con- 

 sequence of their close connec- 

 tion with the liver structure. 



Hepatic duct. The biliary 

 ducts follow the portal vein in 



their mode of branching, and run with the other vessels in the portal 

 canals (fig. 132, rf). They issue from the liver at the transverse 

 fissure in right and left trunks, which by their union form the 

 common hepatic duct.* 



Structure. The moderately-sized hepatic ducts consist of a fibrous 

 coat, lined by a mucous layer ; and penetrating the wall is a longi- 

 tudinal row of openings, on each side, leading into sacs, and into 

 branched tubes which sometimes communicate. 



FIG. 132. VESSELS IN A PORTAL 

 CANAL, AND THE LOBULES OF 

 THE LIVER (KIERNAN). 



I. Lobules of the liver. 



p. Branch of the portal vein, with 

 a, a. small branches which supply 

 interlobular offsets. 



c. Hepatic artery. 



d. Hepatic duct. 



i, i. Openings of interlobular 

 branches of the portal vein. 



* Aberrant ducts exist between the pieces of the peritoneum in the left 

 lateral ligament of the liver, and in the bands bridging over the round ligament 

 and vena cava ; they anastomose together, and are accompanied by branches 

 of the vessels of the liver, viz., portal vein, hepatic artery, and hepatic vein. 



