Superfetation has been known for many centuries; the Romans had laws prescribing the laws of succession in such cases, and many medical writers have mentioned it. Hippocrates and Aristotle wrote of it, the former at some length. Pliny speaks of a slave who bore two infants, one resembling the master, the other a man with whom she had intercourse, and cites the case as one of superfetation. Schenck relates instances, and Zacchias, Velchius, and Sinibaldus mention eases. Pare seemed to be well conversant with the possibility as well as the actuality of superfetation; and Harvey reports that a certain maid, gotten with child by her master, in order to hide her knavery came to London in September, where she lay in by stealth, and being recovered, returned home. In December of the same year she was unexpectedly delivered of another child, a product of superfetation, which proclaimed the crime that she had so cunningly concealed before. Marcellus Donatus, Goret, Schacher, and Mauriceau mention superfetation. In the Academie des Sciences, at Paris, in 1702, there was mentioned the case of a woman who was delivered of a boy; in the placenta was discovered a sort of bladder which was found to contain a female fetus of the age of from four to five months; and in 1729, before the same society, there was an instance in which two fetuses were born a day apart, one aged forty days and the other at full term. From the description, it does not seem possible that either of these were blighted twin pregnancies. Ruysch gives an account of a surgeon's wife at Amsterdam, in 1686, who was delivered of a strong child which survived, and, six hours after, of a small embryo, the funis of which was full of hydatids and the placenta as large and thick as one of three months. Ruysch accompanies his description with an illustrative figure. At Lyons, in 1782, Benoite Franquet was unexpectedly delivered of a child seven months old; three weeks later she experienced symptoms indicative of the existence of another fetus, and after five months and sixteen days she was delivered of a remarkably strong and healthy child.