The Intestines. 227 



Landmarks. For the Duodenum. Starting at the 

 situation of the pylorus, i.e., two and a half inches below 

 and in a line with the right border of the sternum, draw a 

 broad line with convexity to the right and with the widest 

 part of the curve about one inch from the median 

 line, down nearly as far as the level of the umbilicus. 

 The line should now cross the linea alba and should pass 

 upwards, lying the same distance on the left, as on the 

 right of the median line, and terminating above, about one 

 inch below the level of the starting point. The following 

 method may be employed to roughly illustrate the situa- 

 tion of the duodenum below the first part: Slightly flex 

 the index finger and thumb of the left hand so that their 

 tips shall be about one and a half inches apart. Place the 

 tip of the index finger on the landmark for the pyloric 

 opening of the stomach, on the right side of the linea alba, 

 and the centre of (the junction of index finger and thumb 

 in a line with and a little above the umbilicus. The con- 

 cave outline of the finger and thumb so placed will fairly 

 well represent the markings of the U-shaped duodenum. 



For the jejunum and ileum there are no definite 

 landmarks, since there is no permanent relationship of 

 these portions of the small intestine to the regions of the 

 abdomen. Treves states that the portions most commonly 

 found in the pelvis are the lower part of the ileum and that 

 portion of the jejunum with the longest mesentery, viz., 

 that found between six and eleven feet from the end of 

 the duodenum. The ileo-caecal valve is situated in the 

 right iliac fossa, about three and a half inches above the 

 middle of Poupart's ligament, or about half an inch above 

 a line drawn horizontally inwards from the anterior iliac 

 spine and about three inches from this spine, while the< 

 average situation of the tip of the caecum is about one 

 inch above and half an inch internal to the middle of Pou- 

 part's ligament. 



