314 THE ANATOMY OF THE HORSE. 



The exact form of the liver will be more distinctly seen when it has 

 been removed from the body ; but while it remains in situ, the student 

 may endeavour to make out the following points : — Viewing the organ 

 as a whole, it may be described as having an anterior and a posterior 

 siirfacc, and a circumference divisible into an upper and a lower border. 

 The anterior surface is closely applied to the diaphragm, and is convex. 

 The posterior vena cava, in descending from the spine to the foramen 

 dextrum, passes between this surface and the diaphragm ; and its 

 course is marked on the liver by a vertical groove, which may be 

 termed the anterior fissure. The posterior suiface, when the organ 

 is in situ, is concave ; but when the liver is removed from the body, 

 this surface, like the anterior, is slightly convex. It presents the ]jortal 

 fissure (L. porta, a gate), by which the portal vein, hepatic artery, bile 

 duct, and hepatic nerves and lymphatics enter the liver. The upper 

 border shows about its centre a roxmded notch for the reception of 

 the short abdominal portion of the oesophagus. The lower border shows 

 the sharper and deeper indentations dividing the liver into its three 

 principal lobes, and the lesser indentations that partially subdivide the 

 lobulus quadratus. 



The liver is situated in the epigastric and right and left hypo- 

 chondriac regions. Its most important relations, besides those 

 already mentioned, are as follows : — The anterior surface is applied 

 to the diaphragm, the right lobe, which has the highest point 

 of contact, being related to the most superior part of the muscular 

 rim on the right side, the lobulus quadratus corresponding to the 

 phrenic centre, while the left lobe touches the lowest point reached 

 by the liver, and lies against the lower part of the muscular rim 

 on the left side and the adjacent part of the tendinous centre. 

 The posterior surface is related to the stomach, the duodenum, the 

 gastro-hepatic flexure of the double colon, the pancreas, and the 

 right kidney, the latter slightly indenting the upper part of the right 

 lobe. 



If an attempt be made to pull the liver from its position, it will 

 be found that this is opposed by certain folds of peritoneum which 

 pass between it and the abdominal parietes. These are the ligaments 

 of the liver, and they are named as follows: — 



The Biffht Lateral Ligament passes between the right lobe and the 

 adjacent part of the phrenic rim. 



The Left Lateral Ligament attaches the left lobe to the phrenic 

 centre. 



The Falciform or Suspensory Lir/ament attaches the lobulus quadratus 

 to the diaphragm and to the abdominal floor a little to the right of the 

 linea alba. Its posterior edge is concave and free, and contains the 

 shrivelled remains of the umbilical vein — the so-called round ligament. 



