THE LIVER 421 



THE LIVER 



The liver is relatively large, its average weight being about 4 to ^Yi pounds 

 (ca. 2 kg.). It is thick and very strongly curved.' It is divided by three deep 

 interlobar incisures into four principal lobes — right lateral, right central, left 

 central, left lateral; the last of these is usually considerably the largest. On the 

 upp(n- part of tiie right lateral lobe is the caudate lobe and its process. That 

 part of the right central lobe which lies below the portal fissure and to the left of 

 the gall-bladder and cystic duct is homologous with the quadrate lobe of man. 

 The parietal surface is extremely convex, its most anterior part reaching to a 

 plane through the lower part of the sixth or seventh intercostal space. The 



Unibilical fissure ^'■' 



(Esophageal notch 



Hepatic veins 



Fig. 323. — Liver of Pig, Parietal Surface. 

 Photograph of specimen hardened in situ. 



visceral surface is deeply concave; most of it is related to the stomach, for which 

 there is a correspondingly large and deep gastric impression. There is a duodenal 

 impression on the upper part of the right lateral lobe, but no renal impression, as 

 the right kidney does not touch the liver. The fossa for the gall-bladder is 

 mainly on the right central lobe, but also in part on the adjacent surface of the 

 left central lobe. The posterior vena cava enters the dorsal border of the 

 caudate lobe and soon l^ecomes entirely embedded in the gland-substance, emerg- 

 ing only at its passage through the diaphragm. Th(^ esophageal notch is large 

 and is occupied mainly by the large right crus of the diaphragm. The right 



' The description here given is based mainly on the appearance of the organ as hardened 

 in situ, which differs radically from that of the soft organ, as is seen on comparison of the annexed 

 figure (Fig. 321). 



