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ces in other parts of the body: where he takes notice of a concretion seen by himself grown to the Cone of the Heart, of nine ounces weight in an healthy Body, that died of a violent death; and of the like adhering to the Spleen, Kidneys, Liver, without any perceived trouble to the Animal; yea, of some found within the heart it self.
He adds the Number, Shape, and Use of these Placentas; and first observes that those that are Kernel-bearing Animals, or chewing the Cud, have many, and those that are Cake-bearing, have for the most part, one Cake for each Fœtus; but a woman commonly but one, though she happen to have many Embryo's.
He annexes a particular description of the Placenta of a Woman, as the most considerable, and teaches, how it may be most conveniently severed from the Vessels, to render them conspicuous, which are a numerous off-spring of Arteries, Veins, and Fibres; of the last whereof he inquires, whether they be the capillaries of the Arteries, and Veins, or nervous.
The Shape of that in at Woman is Orbicular, about a foot large, and two inches thick; one of its Superficies's, convex, but uneven, the other concave, and every where sticking close to the Chorion.
The Use of the Placenta's is known to be, to serve for conveighing the aliment to the Fœtus. The difficulty is only about the manner. Here are examined three opinions, of Curvey, Everhard, and Harvey. The two former do hold, that the Fœtus is nourished only from the Amnion by the Mouth; yet with this difference, that Curvey will have it fed by the Mouth when it is perfect, but, whilst it is yet imperfect, by filtration only through the pores of the body, and by a kind of juxtaposition: but Everhard, supposing simultaneous formation of all the instruments of nutrition together at first, and esteeming the Mass of bloud by reason of its asperity and eagerness unfit for nutrition, and rather apt to prey upon than feed the parts, maintains, that the liquor is sucked out of the Amnion by the mouth, concocted in the stomach, and thence passed into the Milky Vessels, even from the beginning. Mean time they both agree in this, that the Embryo doth breath, but not feed, through the Umbilical vessels.
This our Author undertakes to disprove; and having asserted the mildness of, at least, many parts of the bloud, and consequently their fitness for nutrition, he defends the Harveyan doctrine, of the Colliquation of the Nourishing Juyce by the Arteries, and its conveyance to the Fœtus by the veins.
