930 THE YASCULAE SYSTEM. 



off, either from the terminal part of the splenic artery or, more commonly, from some of 

 its terminal branches. They pass between the layers of the gastro-splenic ligament to 

 the left part of greater curvature of the stomach, and anastomose with the cesophageal, 

 the left gastric, and the left gastro-epiploic arteries. 



(iii.) The left gastro-epiploic branch arises from the front of the splenic, close to its 

 termination, and passes forwards, between the layers of the gastro-splenic ligament, to the 

 left end of the lower part of the greater curvature of the stomach, along which it is 

 continued, from left to right, between the layers of the greater omentum. It ends 

 by anastomosing with the right gastro-epiploic artery, and it gives off numerous 

 gastric branches to both surfaces of the stomach ; they anastomose with the short gastric 

 and with branches of the left and right gastric arteries. Long slender omental branches 

 pass to the omentum and anastomose with branches of the colic arteries. 



(c) Arteria Hepatica. The hepatic artery (Fig. 771) runs along the upper 

 border of the head of the pancreas to the right gas tro - pancreatic fold of 

 peritoneum, in which it turns forwards to the upper border of the first part of the 

 duodenum. It then passes upwards, between the layers of the hepato-duodenal 

 ligament, anterior to the portal vein and to the left of the bile duct, and reaches 

 the porta hepatis, where it divides into right and left branches. 



Branches. (i.) The right gastric artery is a small branch which arises opposite the 

 upper border of the first part of the duodenum. It runs to the pylorus, between 

 the layers of the lesser omentum, and then turns to the left along the smaller 

 curvature of the stomach. It gives branches to both surfaces of the stomach, and 

 terminates by anastomosing with the left gastric artery. 



(ii.) The gastro- duodenal artery. This branch of the hepatic arises just above the 

 upper border of the first part of the duodenum, descends behind it and terminates opposite 

 its lower border. In its course it lies between the neck of the pancreas and the 

 first part of the duodenum, and anterior to the portal vein. The bile duct is on: 

 its right side. The vessel ends by dividing into the right gastro-epiploic and thej 

 superior pancreatico-duodenal arteries. The right gastro-epiploic artery is the larger 

 of the two terminal branches of the gastro - duodenal ; it passes from right to left, 

 along the greater curvature of the stomach, between the layers of the greater: 

 omentum, and unites with the left gastro-epiploic branch of the splenic artery. From 

 the arterial arch so formed branches pass upwards on both surfaces of the stomach, tci 

 anastomose with branches of the right and left gastric arteries. Other branches pass 

 downwards in the greater omentum, and anastomose with branches of the colic arteries. 

 The superior pancreatico-duodenal artery runs a short course to the right, between the 

 duodenum and the head of the pancreas, and divides into anterior and posterior terminal 

 branches, which descend, the former in front of and the latter behind the head of th( 

 pancreas, to anastomose with similar branches of the inferior pancreatico-duodenal artery 

 They supply the head of the pancreas, anastomosing in it with the pancreatic branches 

 of the splenic artery ; branches are given also to the second part of the duodenum anc 

 to the bile duct. 



(iii.) Terminal branches. The right hepatic artery passes, either in front of or 

 behind the hepatic duct and behind the cystic duct, to the right end of the porta hepatis 

 there it divides into two or more branches which enter the substance of the liver anc 

 accompany the branches of the portal vein and the hepatic duct. As it crosses abov< 

 the junction of the hepatic and cystic ducts, the right hepatic artery gives off a cysti' 

 branch. The cystic artery runs downwards and anteriorly, along the cystic duct, to th< 

 gall-bladder, where it divides into anterior and posterior branches ; the anterior passe 

 downwards between the gall-bladder and the visceral surface of the liver, to both o 

 which it gives offsets ; the posterior branch is distributed on the posterior surface of th 

 gall-bladder, between it and the peritoneum. The left hepatic artery is longer an< 

 narrower than the right. It runs to the left end of the porta hepatis, gives one or tw 

 branches to the caudate lobe, crosses the fossa of the umbilical vein, and breaks u 

 into branches which terminate in the substance of the left lobe of the liver. 



2. Arteria Mesenterica Superior. The superior mesenteric artery (Figs. 77 

 and 773) springs from the front of the aorta, about 12 mm. (half an inch) belo^ 

 the origin of the cceliac artery and opposite the first lumbar vertebra. 



It passes obliquely downwards and forwards, crossing anterior to the left rena 

 vein, the uncinate process of the head of the pancreas, and the third or trans vers 



