BRANCHES OF THE ABDOMINAL AORTA. 713 
arch, passes down on the lateral side of the lateral digit, and is distributed like the 
medial one. 
BRANCHES OF THE THORACIC AORTA 
The bronchial and cesophageal arteries often arise separately. 
There are thirteen pairs of intercostal arteries. The first comes from the 
dorsal, the next four from the subcostal, and the remainder from the aorta directly. 
The two phrenic arteries are very variable in origin. They may come from 
the aorta, the cceliac, left ruminal, or an intercostal or lumbar artery. 
BRANCHES OF THE ABDOMINAL AORTA 
The cceliac artery is about four to five inches (ca. 10-12 cm.) in length. It 
passes ventrally and curves forward between the rumen and pancreas on the left 
and the right crus of the diaphragm and the posterior vena cava on the right. It 
gives off five chief branches. 
1. The hepatic artery arises from the convex side of the curve of the cceliac 
artery as it crosses the posterior vena cava. It passes downward, forward, and to 
the right above the portal vei to the portal fissure, and gives off the following 
branches: 
(1) Pancreatic branches. 
(2) Dorsal and ventral branches go to the corresponding lobes of the liver. 
The ventral branch is the larger; it gives off the right gastric artery, which runs in 
the lesser omentum to supply the origin of the duodenum and the pylorus, anas- 
tomosing with the dorsal branch of the omaso-abomasal artery. 
(8) The cystic artery supplies the gall-bladder. 
(4) The gastro-duodenal artery divides into right gastro-epiploic and pan- 
creatico-duodenal branches. The right gastro-epiploic artery anastomoses with 
the left gastro-epiploic. The pancreatico-duodenal artery anastomoses with the 
first intestinal branch of the anterior mesenteric artery. 
2. The right ruminal artery (A. ruminalis dextra) is the largest branch, and 
usually arises by a short common trunk with the splenic. It runs downward and 
backward on the right face of the dorsal sac of the rumen to the posterior transverse 
fissure, in which it turns around to the left and anastomoses with branches of the 
left ruminal artery. It gives off a pancreatic branch, dorsal and ventral coronary 
arteries, branches to the great omentum, and ramifies on both surfaces of the rumen. 
3. The left ruminal artery (A. ruminalis sinistra) descends on the anterior part 
of the right face of the rumen, enters the anterior furrow, in which it runs from 
right to left, and continues backward in the left longitudinal groove, anastomosing 
with branches of the right artery. It supplies chiefly the left face of the rumen, 
but not its posterior part. It usually gives off near its origin the reticular artery 
(A. reticularis); this rather small vessel passes forward on the dorsal curvature of 
the rumen and turns downward in the rumino-reticular groove, in the bottom of 
which it runs around ventrally to the right side. It gives off a branch which passes 
to the left of the cardia and along the lesser curvature of the reticulum to the neck 
of the omasum. The reticular branches anastomose with the omaso-abomasal and 
left ruminal arteries. 
4. The omaso-abomasal artery (A. gastrica sinistra) appears as the continua- 
tion of the celiac. It passes forward and downward to the greater curvature of 
the omasum, and divides after a course of four or five inches into two branches. 
The dorsal branch curves sharply backward on the dorsal surface of the omasum, 
continues along the lesser curvature of the abomasum, and anastomoses with the 
hepatic artery. It supplies branches to the omasum and to the lesser curvature 
