THE VISCERA OF THE ABDOMEN, OH BELLY. 



67 



and only six times in man, as demonstrated by Mr. Percivall. 

 Of these ninety feet of intestines the greater part is formed by 

 the small guts. 



They possess three coats ; the peritoneal, the muscular, and 

 the mucous : the first, as its name implies, is formed by the peri- 

 toneum ; the second is composed of two orders of muscular 

 fibres, the external of which are aiTancred in a lono-itudiual, and 

 the internal in a vertical, direction, by which means the intestine 

 can be shortened or contracted as may be required. The inter- 



This plate represents the Intestines. 



1, The ccBcutn. 



2, Its apex. 



3 3, Tlie inferior portion of the colon. 



4 4, Its superior portion. 



5, Its inferior and anterior curvature. 



6, Its superior anterior curvature. 



7, Its posterior curvature. 



8, Tlie mesocolon. 



9, The duodenum. 



10 10 10 10, The jejunum. 



11 11, The ileum. 



12 12, The mesentery. 

 13, The rectum. 



nal or mucous coat is of immense extent, beinn; greater indeed 

 than the whole surface of the body. This coat secretes a 

 mucous fluid for its protection, is extremely vascular, and is 

 every where supplied with a set of vessels, called the lacteals, 

 which absorb the nutritious part of the food. 



The small intestines in the human subject are distinguished 

 into three, — the Duodenum, the Jejunum, and the Ileum ; and 

 although these names are not applicable, and their distinctions 

 by no means marked, they are yet still preserved in the horse. 

 The Duodenum then, though twice twelve inches in length, is 



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