DISSECTION OF THE ABDOMEN. 



343 



throughout the liver, the larger hepatic venous trunks are formed • and 

 these, as already seen, enter the posterior vena cava in the anterior 

 nssure of the liver. 



The Hepatic Artery is a branch of the coeliac axis. It enters the 

 liver with the portal vein, and ramifies with it. It has three sets 

 of branches: (1) capsiilai^ 

 branches, to the tunica pro- /- 



pria; (2) vaginal branches, to 

 Glisson's capsule and the 

 vessels within it; and (3) 

 interlobular branches, whose 

 capillaries pass into the 

 lobule, where they help to 

 form the intralobular plexus, 

 and enter the central vein. 

 The capillaries of the vaginal 

 and capsular branches termin- 

 ate in veins that join the 

 portal vessels. 



The Liver Cells. — These are 

 polygonal, granular, nucleated 

 masses of protoplasm, often 

 containing fat particles. They are arranged in columns between the 

 radial strands of the intralobular plexus of capillaries. 



The Bile Passages begin within the lobule as a network of fine canals 

 — the bile capillaries — tunnelled at the lines of apposition of the liver 

 cells. At the periphery of the lobule these become continuous with 

 interlobular bile ducts having a proper vrall and a simple cubical or 

 short columnar epithelial lining. The interlobular bile ducts unite to 

 form the larger ducts that accompany the blood-vessels in the portal 

 canals, and these finally form the main bile duct, which passes in the 

 gastro-hepatic omentum to perforate the wall of the duodenum. 



Fig. 47. 



Transverse Section through the Hepatic 

 Lobules {Turner), 

 i, i, i. Interlotnlar veins ending in the intialobular 

 capillaries; c, c. Central veins joined by the intra- 

 lobular capillaries. At a, a. the capillaries of one 

 lobule communicate witli those adjacent to it. 



steucthee of the spleen. 



The spleen, like the liver, possesses two coats, viz., an outer serous or 

 peritoneal coat, and a deeper fibrous tunic, or tunica propria. The latter 

 is composed of white fibrous tissue with a considerable admixture of 

 elastic and non-striped muscular fibres. It detaches from its inner sur- 

 face a multitude of trabectdce, which by their anastomosis form a fibrous 

 framework in the interior of the organ. The interspaces of this frame- 

 work are occupied by a grumous material — the splenic pulp. If the cut 

 surface of the spleen be washed beneath a tap, the pulp may be removed 

 and the fibrous trabeculfe rendered very evident. 



