This question is mooted, because it has been supposed by some that impregnation ensues from the vapor or odor of the male seed ascending to the womb. Contending parties admit, while others deny, that the seed may be, and has been, detected in the womb of females and animals having been slain (or who may have died) during or soon after the act of copulation. Impregnation has followed very imperfect penetration, such as in cases of unruptured hymen, or of disproportion of parts, and other causes needless to insert here, by which the supposition is supported that conception takes place from vaginal absorption; but it must be remembered that the seed is projected generally with great force, and that the smallest possible quantity is sufficient for impregnation; also, that the vagina possesses a constrictive movement of its own, whereby the seed is carried into the womb.
After the escape of the “albuminous drop,” the vascular membrane which contained it is converted into what is called a corpus luteum; denoting thereby—for it assumes the form, after a while, of a fleshy nucleus—that the female has either conceived, or has been under the influence of strong amatory excitement. This salvo must be admitted, for corpora lutea have been discovered in females where intercourse was even impossible; but as this detection of corpora lutea generally corroborates the surmise that so many conceptions have taken place as there are corpora lutea, it is to be presumed that the exception must be owing to some similarly powerful mental, as well as physical excitement.
When impregnation has taken place, the womb begins to enlarge, and become more soft, vascular, and turgid—the wonderful process of fluids assuming the form of solids commences, and within a fortnight an investing membrane is formed, called the decidua (I will insert as few names as possible), consisting of two kinds of folds, one lining the womb, and the other containing the ovum which has therein “taken root.” The ovum is now a soft oval mass, fringed with vessels, and composed of membranes containing the early fœtus. See sketch.
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When opened, the fœtus appears surrounded by three distinct membranes: first, the decidua; secondly, the chorion, the inner fold of the former; thirdly, the amnios. The decidua, as before stated, lines the womb; the two others cover the ovum or fœtus. After a time the amnios and chorion become adherent to each other, and a fluid is interposed betwixt the amnios and fœtus, called the liquor amnii. The fœtus, as it advances, is perceived to be hanging by an organized support, called the umbilical chord, floating in the liquor before named.[10]
A draft is here presented of an ovum (a section) of a fortnight old; and adjoining is one just double its age, where the chord will be perceived.
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