170 PROFESSOR CHRISTOPHER ADDISON. 



I. General Position of the Duodenum as Eegards the 



Surface. 



Surface Marking. — The measurements in Table V. and on 

 Table III., Appendix (Part II.), relate to the outer or convex 

 border of the duodenum, above, externally, and below, but the 

 width of the duodenum was fully recorded at the various 

 points, and is given in the Plates and on the various Figures 

 of the duodenum. 



Beginning at the upper border of the pylorus, which, it will 

 be remembered, is situated '76 cm. above E.F., 2 cm. to the right 

 of the middle line, the first part of the duodenum passes 

 upwards and outwards and soon attains its highest point, 1"8 cm. 

 above E.F., at a distance of 4 cm. from the middle line. 

 Beginning to descend as the second part, the duodenum, still 

 passing outwards, passes, as a rule, just under cover of the 

 eighth costal cartilage ("25 cm. underneath), immediately in 

 front of the tip of the ninth costal cartilage. Passing still 

 further outwards and downwards, it reaches its extreme right 

 of 7 cm. from the middle line at a distance of 2-5 cm. below 

 E.F. Continuino- downwards at this distance from the middle 

 line with a slightly convex outer border, it bends inwards and 

 attains, about the right lateral line, its lowest point at a 

 distance of 8-7 cm. below E.F., and '7 cm. above the highest 

 part of the iliac crest. Ascending somewhat as it passes 

 inwards, it crosses the middle line 7"9 cm. below E.F., at an 

 average distance of 2 '3 cm. above the umbilicus. From, this 

 point the fourth part bends almost directly upwards. Measured 

 from the lower border in the middle line to the upper border 

 at the duodeno-jejunal flexure, the average ascent of the fourth 

 part of the duodenum is 7*9 cm. : the highest point of the 

 duodeno-jejunal flexure being situated in the plane of E.F. ; 

 and, taking the middle point of the convexity of the flexure, at 

 a distance of 2 "8 cm. to the left of the middle line. 



Summary. — Summarising the foregoing statement in general 

 terms of inches, it may be said that the duodenum commences 

 1 inch to the right of the middle line intersected by E.F,, 

 and passes upwards, outwards, and backwards, to a point about 

 three-quarters of an inch higher and further to the right, where it 



