THE LIVER. 583 



the sub-lobular, (Fig 189, B.) The base enters into the 



constitution of the walls of the sub-lobular vein, and the 



A FIG. 189. B remainder 



of the lobule 

 has its sur- 

 face covered 

 with the cap- 

 sule of Glis- 

 son, in which 



the minute branches of the vena portae, hepatic vein, and 

 hepatic duct ramify. 



The interior of the lobule has its centre (Fig. 189, A) 

 occupied by a vein, called intra-lobular^ which connects it 

 with the sub-lobular vein. The intervals, between the fis- 

 sures of adjacent lobules, are called interlobular fissures ; 

 and the spaces, formed by the apposition of several lobules, 

 are called interlobular spaces. These spaces and fissures 

 are, occupied by the delicate branches of the portal vein, 

 hepatic artery and duct, termed each interlobular, and 

 formed from the plexuses belonging to the sheaths, consti- 

 tuting the portal canals, which are hence called vaginal 

 plexuses. From the interlobular, branches of each set pro- 

 ceed, and enter the lobules, forming plexuses in each, called 

 lobular venous } and lobular biliary plexuses. 



The lobular plexus of the portal vein contains, in its 

 meshes, the acini, or biliary plexus, and is traced into the 

 intra-lobular vein, and thence to the sub-lobular, from 

 which the hepatic veins are formed. It is not settled 

 whether the terminations of the biliary ducts are coecal, or 

 anastomosing arches. 



The lobules, thus constituted, are supposed to be nothing 

 but a congeries of biliary ducts, surrounded by blood-ves- 

 sels. More recent observations, with the microscope, make 

 each acinus to consist of a collection of cells of various size 



FIG. 189, A represents the Lobules of Mr. Kiernan. a Intra-lobular vein. 

 b Interlobular fissure, c Interlobular space. 



FIG. 189, B represents the Sub-lobular vein, a Lobule, b Intra-lobular 

 rein, c Sub-lobular hepatic vein a longitudinal section being made of it. 



