ABDOMINAL CAVITY 447 



extremity of the small curvature. Trace the right gastric artery to its origin 

 from the hepatic artery and follow the latter upwards, in the right border 

 of the lesser omentum, to its division into right and left branches immediately 

 below the porta hepatis. On the walls of the artery some of the fibres of the 

 hepatic plexus of sympathetic nerves may be recognised, and at its side some 

 of the hepatic lymph glands may be seen. Clean both terminal branches of 

 the hepatic artery carefully, especially the right branch which passes either 

 anterior or posterior to the hepatic duct. To the right of the hepatic artery 

 find the common bile duct, trace it downwards to the point where it dis- 

 appears behind the first part of the duodenum and upwards to the upper 

 border of the lesser omentum, where it is formed by the union of the common 

 hepatic duct with the cystic duct. Follow the cystic duct to the neck of 

 the gall-bladder, noting that it makes an S-shaped bend. Continue 

 the incision already made in the gall-bladder into the cystic duct and note 

 that the spiral arrangement of the mucous membrane is continued into the 

 duct. Follow the common hepatic duct upwards into the porta hepatis, to 

 the point where it is formed by the union of the right and left hepatic 

 ducts which come respectively from the right and left lobes of the liver. 

 Clean away the fascia from between the hepatic artery and the common 

 bile duct and display the portal vein which lies behind them. Trace it 

 upwards to its division into right and left branches, at the porta hepatis, 

 and downwards to the first part of the duodenum where it disappears from 

 view at the present stage of dissection. Note that the portal vein lies 

 immediately in front of the epiploic foramen (Winslow) and that its posterior 

 surface is covered by the peritoneum of the anterior margin of the foramen. 



Omentum Majus (The Greater Omentum). After he has 

 displayed and studied the structures situated between the two 

 layers of the small omentum the dissector should examine 

 the greater omentum. It hangs down, like an apron, before 

 the viscera which lie in the lower part of the abdomen. It is 

 a double fold of peritoneum and consists, therefore, of two 

 anterior and two posterior layers, the former being separated 

 from the latter by a portion of the cavity of the omental bursa. 

 The upper margins of the two anterior layers are attached to 

 the lower part of the great curvature of the stomach, where 

 they become continuous with the peritoneum on the anterior 

 and posterior surfaces of that viscus. To the left and 

 above, the two anterior layers are continuous with the two 

 layers of the gastro-lienal ligament, but at a lower level 

 the two anterior layers become continuous with the two 

 posterior layers at the free left border. Similarly at the 

 lower and the right margins of the greater omentum the two 

 anterior become continuous with the two posterior layers. 

 The upper margins of the two posterior layers are attached 

 to the lower border of the transverse colon, and, through the 

 peritoneum on the anterior and posterior surfaces of the 

 latter, they become continuous with the two layers of the trans- 

 verse meso-colon, which attaches the transverse colon to the 



