434 



DIGESTIVE SYSTEM OF THE DOG 



the lesser curvature of the stomach), which separates two deep cavities. The 

 depression to the left of the ridge is occupied by the body and fundus of the stomach. 

 The depression on the right is smaller, and is occupied by the pyloric part of the 

 stomach, the origin of the duodenum, and the right branch of the pancreas. The 

 gall-bladder is not visible. 



When the stomach is empty and contracted, the visceral surface of the Hver is strikingly 

 different. There is then a shallow impression for the left part of the stomach on the left lobe, 

 and a large convex area, related to the small intestine and a mass of omentum. The pyloric 

 and duodenal impressions are not much changed. The gall-bladder is visible. 



The portal fissure is very deep and might well be termed a fossa. It is bounded 



on the right (externally) by the caudate process, on the left (internally) by the 



papillary process or lobe, which is directed ventrally. The hepatic artery enters 



at the dorsal end and the portal vein centrally, while the bile duct leaves at the 



ventral part. The left central lobe is not visible, and the right 



^ central one is largely concealed. 



The parietal surface is extremely convex, being adapted to 

 the diaphragm and the adjacent part of the ventral wall of the 

 abdomen. On it all the lobes except the papillary are com- 

 pletely or partially visible. The gall-bladder is visible in the 

 fissure between the quadrate and chief portions of the right 

 central lobe. 



The dorsal border presents a renal impression on its right 

 portion. The posterior vena cava passes dowTiward and forward 

 at first in a deep groove on the caudate lobe, then largely embed- 

 ded in the parietal surface of the right lateral lobe; it receives 

 two large hepatic veins just before piercing the diaphragm. 



The oesophageal notch is large, and is occupied on the right 

 by the thick margin of the hiatus a?sophageus. The left l)order 

 is opposite to the ninth and tenth ribs; it is thin and is marked 

 by numerous indentations. The caudate process extends usually 

 a little beyond the last right rib, between the right kidney and 

 the right branch of the pancreas. The ventral border lies on 

 the ventral abdominal wall a variable distance behind the 

 xiphoid cartilage. 



The gall-bladder lies in the fossa vesicae felleae, between the 

 two parts of the right central lol)e; it does not reach to the ven- 

 tral border of the liver. The cystic duct joins the hepatic duct 

 at the lower part of the portal fissure, forming with it the bile 

 duct (Ductus choledochus) ; the latter passes to the right and 

 opens into the duodenum, about two or three inches (ca. 5 to 

 8 cm.) from the pylorus. 

 Of the ligaments, the coronary and right lateral are well developed, but the 

 left lateral and falciform are small. 



Fig. 341. — Spleen of 

 Dog, Visceral 

 Surface. 



a, a. Ridge; h, 

 ventral end; c, dorsal 

 end. (After EUen- 



berger, in Leisering's 

 Atlas.) 



THE PANCREAS 

 The pancreas is V-shaped, consisting of two long narrow branches, which 

 meet at an acute angle above the pylorus. The right branch extends backward 

 above the first part of the duodenum, below the caudate lol)e of the liver and the 

 right kidney, and ends usually a short distance behind the latter. The left branch 

 passes inward and backward on the visceral surface of the stomach, and ends 

 under the left kidney. There are two ducts : the larger one unites with the bile 

 duct, while the smaller one enters the duodenum an inch or two (ca. 3 to 5 cm.) 

 further back. 



