Addison describes the case of a woman who was delivered of a healthy male child, and everything was well until the evening of the fourth day, when intense labor-pains set in, and well-formed twins about the size of a pigeon's egg were born. In this strange case, possibly an example of superfetation, the patient made a good recovery and the first child lived. A similar case is reported by Lumby in which a woman was delivered on January 18th, by a midwife, of a full-grown and healthy female child. On the third day she came down-stairs and resumed her ordinary duties, which she continued until February 4th (seventeen days after). At this time she was delivered of twins, a boy and a girl, healthy and well-developed. The placenta was of the consistency of jelly and had to be scooped away with the hand. The mother and children did well. This woman was the mother of ten children besides the product of this conception, and at the latter occurrence had entire absence of pains and a very easy parturition. Pincott had a case with an interval of seven weeks between the births; Vale 1 of two months; Bush 1 of seventeen days; and Burke 1 with an interval of two months. Douglas cites an instance of twins being born four days apart. Bessems of Antwerp, in 1866, mentions a woman with a bicornate uterus who bore two twins at fifty-four days' interval. CHAPTER IV. PROLIFICITY. General Historic Observations.--Prolificity is a much discussed subject, for besides its medical and general interest it is of importance in social as well as in political economy. Superfluous population was a question that came to consciousness early; Aristotle spoke of legislation to prevent the increase of population and the physical and mental deterioration of the race,--he believed in a population fixed as regards numbers,--and later Lycurgus transformed these precepts into a terrible law. Strabonius reports that the inhabitants of Cathea brought their infants at the age of two months before a magistrate for inspection. The strong and promising were preserved and the weak destroyed. The founders of the Roman Empire followed a similar usage. With great indignation Seneca, Ovid, and Juvenal reproved this barbarity of the Romans. With the domination of Christianity this custom gradually diminished, and Constantine stopped it altogether, ordering succor to the people too poor to rear their own children. The old Celts were so jealous of their vigor that they placed their babes on a shield in the river, and regarded those that the waves respected as legitimate and worthy to become members of their clans. In many of the Oriental countries, where the population is often very excessive and poverty great, the girl babies of the lower classes were destroyed. At one time the crocodiles, held sacred in the Nile, were given the surplus infants. By destroying the females the breeding necessarily diminished, and the number of the weaker and dependent classes became less.