312 THE ANATOMY OF THE HORSE. 



to the pancreas and base of the spleen. The stomach is retained in 

 position by continuity with the oesophagus and duodenum, and by 

 certain folds of peritoneum, viz., the gastro-phrenic ligament, and the 

 gastro-hepatic, gastro-splenic, and gastro-colic omenta. The gastro- 

 phrenic ligament extends from the diaphragm to the stomach, around 

 the oesophageal insertion. The gastro-hepatic amentum passes between 

 the lesser curvature and the posterior fissure of the liver. The gastro- 

 splenic omentum passes from the cardiac extremity to the spleen. The 

 gastro-colic or great omentum is continuous with the preceding, and 

 passes in the form of a loose fold from the greater curvature. It 

 extends backwards and downwards, and then curves upwards to the 

 roof of the abdominal cavity; and, as has already been explained 

 (page 300), it separates the greater and lesser cavities of the perito- 

 neum; and, inasmuch as in man it hangs downwards to float upon 

 the intestines, it has been termed the Epiploon. Even in emaciated 

 subjects, it contains between its layers a considerable quantity of 

 fat. 



The Duodenum (Plates 43 and 44). A better opportunity to examine 

 this part of the intestine is now afforded. Commencing in the epigas- 

 trium, at the pyloric orifice of the stomach, it ascends across the posterior 

 face of the right lobe of the liver, in passing into the right hypochon- 

 drium. It then curves backwards in the right lumbar region, beneath 

 the right kidney; and sweeping round the crook of the osecum, it crosses 

 the spine and is continued as the jejunum. Its calibre is greatest just 

 beyond the pylorus, and at this point it presents, when inflated, a small 

 dilatation like a miniature stomach with its greater curvature superior. 

 Throughout the whole of its course it is retained in position by a narrow 

 band of peritoneum formed by the serous membrane as it passes to 

 envelop the bowel. The right extremity of the pancreas rests against the 

 duodenum, a few inches from the pylorus, and at that point the wall 

 of the bowel is perforated by the bile and pancreatic ducts. 



The Spleen (Plates 43 and 44) is a bluish-purple solid organ placed 

 in close proximity to the left sac of the stomach. In the horse it has 

 a scythe-shaped outline. It presents an external face, which is slightly 

 convex; an internal face, which is slightly concave and narrower than 

 the outer; an anterior thick border; and a posterior border, which is 

 sharp. Its surfaces are widest above, where they terminate in the base 

 of the organ, and below they taper to the apex. The spleen is situated 

 in the left hypochondriac region, and has the following relations : — Its 

 outer surface is related to the diaphragm; its inner surface contacts with 

 the double colon ; its anterior border is penetrated by the vessels and 

 nerves of the organ, and is related to the gTeater curvature of the 

 stomach ; its posterior border is free, and is included between the intes- 

 tines and the diaphragm ; its base is related to the pancreas and left 



