528 TEE AETEE1ES. 



axis, this artery is directed downwards and to the left, lying beside its 

 satellite vein and the superior face of the left extremity of the pancreas. 

 It reaches the anterior fissure of the spleen in turning round the large tube- 

 rosity of the stomach, passes along the entire length of that fissure, and leaving 

 it only near the point of the organ to throw itself into the great omentum, 

 where it is named the left gastro-omental artery (or gastro-epiploica sinistra). 

 The splenic artery gives off, during its course, very numerous collateral 

 branches. These are : 



1. External or splenic ramifications, which immediately enter the 

 substance of the spleen. 



2. Internal or gastric ramifications, also called the short vessels (vasa 

 brevia) in Man, which are comprised between the two layers of the gastro- 

 splenic omentum, and go to the great curvature of the stomach, where they 

 nearly always divide into two branches : one which ramifies on the anterior 

 wall of the viscus, the other on its posterior wall. These vessels inosculate 

 with those sent to the membranes of the stomach by the proper gastric artery. 



3. Posterior or omental twigs of little importance, destined for the great 

 omentum. 



Left gastro-omental artery. This artery follows the great curvature 

 of the stomach to a. distance varying with the state of repletion of that 

 viscus, passing between the two layers of the omentum, and inosculating 

 with the right gastro-omental artery. The branches it sends off on its 

 track are descending or omental, and ascending or gastric ; the latter being 

 disposed exactly like the analogous branches emanating directly from the 

 splenic artery. 



3. HEPATIC ARTERY. Applied to the superior face of the pancreas, and 

 incrusted, as it were, in the tissue of that gland, whose anterior border it 

 follows, the hepatic artery is directed from left to right, passes under the 

 posterior vena cava, which it crosses obliquely, reaches the posterior fissure 

 of the liver, and enters it with the vena portaB to become broken up into 

 several branches, whose ultimate divisions carry nutritive blood to the lobules 

 of the liver. 



Before reaching that organ, however, the hepatic artery furnishes the 

 pancreatic branches., the pyloric artery, and the right gastro-omental artery. 



Pancreatic arteries. Irregular and very numerous, these branches are 

 detached from the hepatic artery on its passage over the superior face 

 of the pancreas, and plunge into the tissue of that gland, whose arterial 

 blood is chiefly derived from this source. 



Pyloric artery. This vessel arises at the dilatation towards the origin 

 of the duodenum, before the hepatic artery enters the posterior fissure 

 of the liver, and most frequently by a trunk common to it and the right 

 gastro-omental artery. It passes towards the small curvature of the 

 stomach, and sends off branches around the pylorus, which anastomose 

 with the posterior gastric arteries and the right gastro-omental artery. 



Right gastro-omental artery (gastro-epiploica dextra). This artery crosses 

 the duodenal dilatation inferiorly and posteriorly, to place itself in the 

 substance of the great omentum ; in doing which it passes along the great 

 curvature of the stomach, and anastomoses by inosculation with the left 

 gastro-omental artery. In its course, it throws off ornental and gastric 

 branches, which are analogous to those emanating from the latter vessel. 

 Before crossing the duodenum, it also emits a particular branch, designated 

 in treatises on Veterinary Anatomy the duodenal artery ; this is a somewhat 

 considerable division, which follows the small curvature of the duodenum in 



