4o UNIVERSITY OF MISSOURI STUDIES 



sacrum and coccyx by connective tissue containing nerves, 

 blood vessels and lymph glands. On either side of the rec- 

 tum are the large vessels and nerves which pass out through 

 the great sacrosciatic notch (Plates XXII and XXIII). 

 Anteriorly it is in relation above with the pelvic portion of 

 the sigmoid colon and below with the bladder. The ureters 

 and vasa def erentia pass across the lower part of the anterior 

 surface to gain the posterior surface of the bladder (Plate 

 XXIII). The lower half of the rectum is contracted. Its 

 anterior wall is a vertical continuation of the anterior wall 

 of the upper half. It is surrounded by the cone-shaped 

 levator ani muscle with which its muscular coat becomes 

 continuous near the anus (Plates XXIV and XXV). It is 

 in contact above, anteriorly with the prostate gland and 

 posteriorly wtih the tip of the coccyx. Its lower part is 

 separated from the bulb of the urethra anteriorly by the 

 perinaeal body. Its relation to the ischiorectal fossae 

 posterolaterally is well shown in Plates XXIV and XXV. 



THE LIVER 



The liver is seen in section in Plates XII to XVIII 

 and in projection in Plates XXVIII to XXXV. The greater 

 part of it lies in the right hypochondriac region, but it 

 crosses the epigastric into the left hypochondriac region. 

 The superior boundary of the surface outline is nearly 

 horizontal and crosses the sternum at the level of the fifth 

 sternochondral articulations and the upper border of the 

 ninth thoracic vertebra. In the midclavicular regions this 

 boundary is in the fourth intercostal spaces only a few milli- 

 meters higher than at the midline. This slight difiference 

 is due to the fact that the left dome of the diaphragm is at 

 nearly the same level as the right one. The right boundary 



