How comes it that nowadays, by a reversal of things, the tender body of a little babe has limbs nearer akin to stone ?" Many of the older writers mention this form of fetation as a curiosity, but offer no explanation as to its cause.

Mauriceau and de Graaf discuss in full extrauterine pregnancy, and Salmuth, Hannseus, and Bartholinus describe it.

From the beginning of the eighteenth century this subject always demanded the attention and interest of medical observers.

In more modern times, Campbell and Geoffroy-Saint-Hilaire, who named it "Grossesse Pathologique," have carefully defined and classified the forms, and to-day every text-book on obstetrics gives a scientific discussion and classification of the different forms of extrauterine pregnancy.
The site of the conception is generally the wall of the uterus, the Fallopian tube, or the ovary, although there are instances of pregnancy in the vagina, as for example when there is scirrhus of the uterus; and again, cases supposed to be only extrauterine have been instances simply of double uterus, with single or concurrent pregnancy.

Ross speaks of a woman of thirty-three who had been married fourteen years, had borne six children, and who on July 16, 1870, miscarried with twins of about five months' development.