The craniopagus shown in Figure 1 was delivered at the Madison General Hospital, May 5, 1919, in a case attended by Dr. Walter H. Sheldon. The twins weighed 11 pounds and 1 ounce at the time of birth. The faces and bodies were practically in vertical alinement. One of the twins, which I shall hereafter refer to as A, was a well developed female; the other, which I shall refer to as B, had an imperforate anus and an imperforate "penis" as large as a normal infantile penis. Subsequently, at a postmortem examination, Dr. C. H. Bunting found that the internal genital organs of A were apparently normal. B had normal ovaries, but its uterus was four times the normal size. In B, furthermore, the sigmoid colon, greatly distended, emptied into a cloaca. The left umbilical artery in B was either
very small or was absent. In A, both umbilical