THE SMALL COLON 



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other bands appear, so that the flexure has three bands; two of these are dorsal 

 and free, the third is ventral and concealed. The last part has three bands, of 

 which the inner antl outer ones are free, the ventral one covered. 



The Small Colon 

 The small colon (Colon tenue) begins at the termination of the great colon, 

 behind the saccus csecus of the stomach and below the left kidney, and is continued 

 by the rectum at the pelvic inlet. Its length is about ten to twelve feet (ca. 3.5 m.), 

 and its diameter about three to four inches (ca. 7.5 to 10 cm.). 



Fig. 272. — Pelvic L>jlet and Posterior Part of Abdominal Wall of Horse, Viewed from the Front. 

 The left inguinal canal is partially opened. The peritoneum is retained except over a part of the left cre- 

 master muscle. The sublumbar region is greatly foreshortened in this view, a, a', Kidneys; a", adrenal; 6., 

 ureter; c, renal artery; rf, aorta; e, coeliac artery (cut); /, anterior mesenteric artery (cut); 3, posterior mesenteric 

 artery; h, circumflex iliac artery; i, external iUac artery; A;, internal iliac artery; I, spermatic artery in peritoneal 

 fold (phca vasculosa), m; n, vas deferens, inclosed in urogenital fold, o; p, urinary bladder; q, round ligament of 

 bladder; r, middle ligament of bladder; s, rectum; t, margin of vaginal ring; u, posterior abdominal artery; v, 

 external pudic artery; w, rectus abdominis muscle; x, transversus and obliquus internus abdominis; y, y' , cre- 

 master externus; z, posterior vena cava (cut). (After Ellenberger-Baum, Top. Anat. d. Pferdes.) 



Its coils lie in the space between the stomach and the pelvic inlet, dorsal to 

 the left portions of the great colon. They are mingled with those of the 

 small intestine, from which they are easily distinguished by the taeniae and 

 sacculation. 



It is attached to the sublumbar region by the colic mesentery, and to the 

 termination of the duodenum by a short peritoneal fold (Lig. duodeno-colicum). 

 The great omentum is also attached to the origin of the bowel. The colic mesen- 

 tery is narrow at its origin, but soon reaches a wudth of aljout three feet (ca. 

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