200 PROFESSOR CHRISTOPHER ADDISON. 



was an interruption of more than 6 cm. before a lowly-starting 

 meso-sigmoid commenced. In case 32, throughout, and in case 

 23, with a slight interruption at the lower end of the spleen, 

 there was a complete descending meso-colon in the normal line 

 outside the kidney, continued below into the meso-sigmoid. So 

 that in all the cases so far described on both sides the line of 

 the meso-colon was that of the normal inner peritoneal reflec- 

 tion on to the colon. 



In case 26, however, in a girl set. 16, there was a complete 

 descending meso-colon of a different character, with the follow- 

 ing conditions : — The attachment of the root of the mesentery 

 in the right psoas region was normal. The ceecum and 

 appendix were wholly within the pelvis. 



The transverse colon crossed the middle line at the usual 

 level, but at a point 5 cm. to the left of the middle line, 1 cm. 

 above E.F., it turned downwards and inwards as a descending 

 meso-colon, passing beside the fourth part of the duodenum 

 towards the middle line, which it reached at the level of the 

 umbilicus, and passed thence straight downwards into the pelvis 

 to become the meso-rectum. The outer border of the descend- 

 ing colon in the plane of E.F. was 9 cm. from the middle line, 

 and the colon then passed downwards and inwards, parallel with 

 its mesenteric attachment over the left kidney towards the 

 middle line, which it attained in the plane of CD. Thence 

 the colon passed without any sigmoid flexure or other tortuosity 

 directly into the rectum. The case presented an excellent 

 example of a primitive mesentery for the lower part of the 

 bowel. 



Cysto-Colic Fold. 



The fold of peritoneum passing from the gall-bladder to 

 the hepatic flexure of the colon has been already described 

 (pp. 174-5). It occurred in 12 cases, or 30 per cent, of the 

 series— viz., in cases 5, 8, 19, 21, 22, 23, 24, 25, 27, 28, 32, 33. 



All but two cases— Nos. 32 and 22 — presented that which will 

 be described as the first and chief variety of the transverse 

 colon — namely, that characterised by a marked, and more or 

 less firm, downward hepatic loop. 



The CostO'Colic ligament has already been considered. 



