THORAX AND ABDOMEN OF THE HORSE 123 



falciform'^ ligament (ligamentum falciforme hepatis), a narrow, sickle- 

 shaped band, with a free dorsal edge, that begins on the ventral wall 

 of the abdomen near the umbilicus. From this point it may be 

 followed forwards from the abdominal wall on to the diaphragm, 

 gradually increasing in width, until it reaches the liver where its free 

 border disappears into the umbilical fissure. The free edge of the liga- 

 ment contains a feeble fibrous cord, the shrivelled remains of the umbilical 

 vein, generally known as the round ligament (ligamentum teres 

 hepatis). If the falciform ligament be traced up the diaphragmatic 

 surface of the liver, it will be found that the two layers of peritoneum 

 that compose it separate when the caudal vena cava is reached. The 

 layers diverge to right and left to become the right and left laminse of 

 the coronary- ligament (ligamentum coronarium hepatis), which forms 

 a connection between the liver, in the neighbourhood of the vena 

 cava, and the immediately adjoining part of the diaphragm. An 

 offshoot from the coronary ligament crosses the edge of the liver at the 

 oesophageal notch and becomes continuous with the lesser omentum. 



Laterally the coronary ligament is continuous with the right and 

 left triangular ligaments. The right triangular ligament (ligamentum 

 triangulare dextrum) is a strong and very definite fold of peritoneum 

 connecting the edge of the right lateral lobe to the dorsal costal part of 

 the right half of the diaphragm. The left triangular ligament (liga- 

 mentum triangulare sinistrum) in like manner attaches the left lateral 

 lobe to the tendinous part of the left half of the diaphragm. An 

 offshoot from the right triangular ligament connects the caudal dorsal 

 border of the caudate process to the right kidney and the caecum, and 

 is distinguished as the hepato-renal ligament (ligamentum hepato- 

 renale). 



The peritoneal connections of the liver with the stomach and the 

 duodenum have already been studied (pages 115 and 117). 



Bile duct (Ductus choledochus^). — The absence of a gall-bladder in 

 the horse makes for greater simplicity in the arrangement of the ducts 

 whereby bile is conveyed from the liver to the intestine. The bile duct 

 is formed in the region of the porta by the union of two hepatic ducts — 

 one, the larger, from the left lateral and central lobes; the other from 

 the right lateral lobe. The single vessel so formed is about 5 cm. in 

 length, and passes towards the right, between the two layers of the 

 hepato-duodenal ligament, to open into the duodenum, in common with 

 the pancreatic duct, about 13 to 15 cm. from the pylorus. The 



^ Falx [L.], a sickle ; forma [L.], form. 



- Corona [L.], a crown ; coronarius [L.], encircling after the manner of a crown. 



3 xoXt? (chole) [Gr.], bile ; oexecrdai (dechesthai) [Gr.], to receive. 



