THORAX AND ABDOMEN OF THE HORSE 125 



the ventral border of the aorta immediately this vessel has passed 

 through the diaphragm. The coeliac artery is scarcely more than 1 cm. 

 in length, and divides into three branches — the left gastric, splenic and 

 hepatic. 



(1) A. gastrica sinistra. — The left gastric artery is the middle one 

 of the three vessels. It passes towards the cardia of the stomach, where 

 it ends by dividing into cranial and caudal branches. In addition, it 

 contributes an cesophageal branch and several twigs to the pancreas. 

 (a) Pancreatic hranches (rami pancreatici) supply the middle part of 

 the gland. (6) The (Esophageal branch (ramus ossophageus) is some- 

 what variable in its origin. Instead of arising from the main stem of 

 the gastric, it may leave the caudal branch of this artery. In other 

 cases it leaves the splenic artery. Whatever its origin, it follows the 

 dorsal border of the oesophagus through the diaphragm into the thorax, 

 where it anastomoses with the oesophageal artery, (c) The cranial branch 

 (ramus cranialis) of the left gastric artery crosses the lesser curvature of 

 the stomach to the right of the cardia, and is distributed over the 

 cranial surface of the organ, (d) The caudal branch (ramus caudalis) 

 passes to the right along the lesser curvature and ramifies on the caudal 

 surface of the stomach. Twio^s from both the cranial and the caudal 

 branches establish numerous anastomoses with the right gastric and 

 short gastric arteries. 



(2) A. lienalis. — The splenic artery passes towards the left, across 

 the saccus csecus of the stomach, and so gains the base of the spleen. 

 Running down the hilus to the apex of this organ, it becomes the left 

 gastro-epiploic artery. Its branches are : — (a) Pancreatic branches 

 (rami pancreatici) to the left extremity of the gland, (b) Numerous 

 splenic branches (rami lienales) leave the splenic artery as it traverses 

 the hilus, and immediately sink into the substance of the spleen. 



(c) From the opposite (concave) border of the splenic numerous short 

 gastric arteries (aa. gastricae breves) arise and pass between the two 

 layers of the gastro-splenic ligament to reach the greater curvature of 

 the stomach. They anastomose with branches of the left gastric artery. 



(d) On passing beyond the apex of the spleen the splenic becomes the 

 left gastro-epiploic ^ artery (a. gastroepiploica sinistra). This runs from 

 left to right between the two layers of the great omentum, supplies 

 numerous omental branches and several short gastric arteries, and ends 

 by anastomosing with the right gastro-epiploic artery. 



(3) A. hepatica. — The hepatic artery pursues an oblique course to 

 the right and ventralwards to reach the visceral surface of the liver, 

 where it divides into proper hepatic and gastro-duodenal arteries. The 



1 eitiirXoov (epiploon) [Gr.], the cai;l of the entrails = omentum [L.]. 



