DISSECTION OF THE ABDOMEN. 305 



breadth of twelve fingers. The remainder of the small intestine has a 

 comparatively loose mode of suspension ; and it is arbitrarily divided 

 into jejunum and ileum, the former succeeding the duodenum and 

 measuring about thirty feet, the latter comprising the remainder of 

 the tube — about forty feet. These terms are borrowed from human 

 anatomy, where the term jejunum was applied in consequence of that 

 portion of the intestine being generally found empty in the dead 

 body, while the ileum was so designatea on account of its convoluted 

 disposition. 



The Large Intestine is, for the most part, of vastly greater calibre 

 than the small ; and, unlike the latter, it has when distended, not 

 a smooth, but a bosselated surface. In a medium-sized animal it 

 is about twenty-five feet in length. It is subdivided— and in a much 

 more natural fashion than the small intestine — into ccecum, colon, and 

 rectum, the colon being further subdivided into double and single 

 colon. 



When the muscles which enclose the abdomen below and on each side 

 have been removed it most commonly happens that only the large 

 intestines are exposed, and consequently their examination must precede 

 that of the small intestines. 



The Cecum is the first of the large intestines. In an animal of 

 medium size it measures about three feet in length, and when moderately 

 distended it has a capacity of about four gallons. At one of its extremi- 

 ties it is curved, forming what is termed the crook of the caecum, while 

 the opposite extremity tapers to a blind point, frcm which the bowel is 

 named. The bowel has a puckered appearance, which is most evident 

 when it is distended. This is owing to the longitudinal muscular fibres 

 of its wall being not uniformly distributed as they are in the small intes- 

 tine, but collected into bands, which shorten the bowel by throwing it 

 into folds. The terminal portion of the ileum (small intestine) joins the 

 caecum on the concave side of the crook, and a few inches above the 

 point of communication is the orifice by which alimentary matters are 

 passed on to the colon. The crook of the caecum is fixed in the right 

 sublumbar region by means of loose cellular tissue, and it is in contact 

 with the right kidney and the pancreas. On its inner side it adheres by 

 cellular tissue to the termination of the double colon, and the duodenum 

 passes round it on the outer side. The remaining portion of the bowel 

 extends downwards and forwards through the right hypochondriac region, 

 terminating by its blind point in the epigastrium. The first portion of 

 the large colon, which lies to its inner side, extends in the same direction, 

 and the peritoneum in passing from the one bowel to the other forms 

 a fold which has been termed the meso-caecum. As the caecum is not 

 adherent to the abdominal parietes except in the neighbourhood of its 

 crook, it admits of some displacement ; and the student must therefore 



