Page:Philosophical Transactions - Volume 002.djvu/112

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furnishes the Reader with no vulgar Observations. He concludes this Chapter by observing, that there is also Air in the said Membranes; which besides other Arguments, he proves from the crying of Infants in the Womb (of which he alledges a memorable and well attested example in a Child of an English Lady in Cheshire, the Child being yet alive and in good health;) and from Chickens, often heard to peep in the Egg, both before the breaking of the shells, and after, the Membranes being yet entire; adscribing the production of this Air to the spirituous liquor in the Membrane, apt to ferment, and thereby causing store of exhalations.

The fourth Chapter discourses of the Umbilical Vessels; and observes first, that they differ in different Animals, and hold proportion to the Membranes and Liquors, so as those that have two Liquors, have four Membranes, and three Liquors have six: the Oviparous also being furnished with a Ductus, passing to the Guts, because they want breasts, and their yolk is shut up in the belly.

The Umbilical Arteries, belonging to the Placenta, and commonly said to he derived from the Crurals, are by him affirmed to proceed from the end of the Aorta. They are here described, and their several portions distributed for the Chorion and Amnion. Then an account is given of the Hepatick Vein, corresponding to the Arteries. It is in Viviparous Animals inserted into the Vena Porta, passing again with the remaining Bloud thorow the Canalis Venosus into the Cava, without percolation made in the Liver. In Birds it enters not into the Liver, but passes over its convexity into the Cava. A description is also made of the Urachus, found in all Viviparous Creatures, though by many Writers denied to be in Man, who notwithstanding hath need, as well as other such Animals, somewhere to lodge his Urine. The Oviparous want this Umbilical funiculus, but yet are furnished with fit sanguineous Vessels, which here also are explained; especially the Ductus Intestinalis, said to be omitted by Dr. Harvey, and to have been known to the Author long before Mr. Steno claimed the discovery of it; for which he appeals to the testimony of Mr. Boyle, and three worthy Physicians, Willis, Millington, and Lower; as also to that of two ingenious Frenchmen, Guison, and Fiard, to whom our Author affirms to have shewed Anno 1659, when they were going over into Holland, not only this Ductus, but also the Ductus Salivales, and the Passages of the Nostrils, published afterwards by the said Steno.

The use of this Ductus Intestinalis is esteemed to be the conveighing

of