The examples of multiple births of a single pregnancy will be taken up under their respective numbers, several examples of each being given, together with the authorities. Many twin and triplet brothers have figured prominently in history, and, in fact, they seem especially favored. The instance of the Horatii and the Curatii, and their famous battle, on which hung the fate of Rome and Alba, is familiar to every one, their strength and wisdom being legendary with the Romans. Twins and triplets, being quite common, will not be considered here, although there are 2 cases of interest of the latter that deserve citation. Sperling reports 2 instances of triplets; in the first there was 1 placenta and chorion, 2 amnions, and the sex was the same; in the second case, in which the sexes were different, there were 3 placentas, 3 chorions, and 3 amnions. What significance this may have is only a matter of conjecture. Petty describes a case of triplets in which one child was born alive, the other 2 having lost their vitality three months before. Mirabeau has recently found that triple births are most common (1 to 6500) in multiparous women between thirty and thirty-four years of age. Heredity seems to be a factor, and duplex uteruses predispose to multiple births. Ross reports an instance of double uterus with triple pregnancy. Quadruplets are supposed to occur once in about every 400,000 births. There are 72 instances recorded in the Index Catalogue of the Surgeon General's Library, U. S. A., up to the time of compilation, not including the subsequent cases in the Index Medicus. At the Hotel-Dieu, in Paris, in 108,000 births, covering a period of sixty years, mostly in the last century, there was only one case of quadruplets. The following extract of an account of the birth of quadruplets is given by Dr. De Leon of Ingersoll, Texas:--