The roentgenographic configurations cast by the pubic bones and their symphysis have aroused my special interest. In an effort to interpret these more fully, studies have been made on seventy-five specimens of this anatomic region, 1 obtained post mortem. The specimens were examined histologically and roentgenographically for the purpose of elucidating the following questions: 1. How does the symphysis pubis develop and is it a true joint? 2. What should be considered its normal appearance until puberty? 3. Are there any growth changes after adolescence 4. What changes in this area after middle age may be deemed normal? 5. What changes occur in the symphysis pubis during pregnancy? 6. What modifications are produced in this region by the local presence of pathologic tissue? METHOD OF STUDY In the course of seventy-five autopsies, the portion of the body in the region of the symphysis pubis was removed. The specimens came from