Page:Philosophical Transactions - Volume 002.djvu/111

 In the third Chapter, the Membranes and Humors of Embryo's are considered, The Membranes are in some, three, in others, four, in an Egg, six. All Placentiferous Animals (if I may assume this word) he affirms to have three Membranes, and Sows, Mares, and Women also; but only two Humors. Again, Bitches, Cats, and Conies, four Membranes, and three Humors; so that the Number of the Membranes hath been hitherto observed alwaies to exceed that of the Humors.

Giving the History of both, he begins from Sheep, Cows, and other Ruminating Animals, describing first the Chorion, assigning its Use, and comparing it with that in Deer, Sows, Mares, Women, Rabbets, Bitches, and Cats, when with young. Then he proceeds to the description of the Allantiodes (the Membrane immediately encompassing that skin, wherein the Fœtus is wrapped) and thence to that of the Amnion, wherein the Embryo it self lieth, swimming in its alimental liquor. And lastly to that which is observed to be in Bitches, Cats, and Rabbets, and contains a very good and nourishing Juyce; which how it comes thither, is a difficult inquiry, as well as that other, how the liquor gets into the Amnion. To resolve both which our Author, having disproved the Filtration of the liquor, held by Carvey and Everhard out of the Chorian into the Amnion, and evinced, that the liquor in the Allantoides, interjected between these two is Urinous, he concludes, that the alimentary Juyce passes through the Umbilical Vessels by a proper Artery, depositing it in those Membranes we speak of, and referring it there for the use of the Fœtus.

Concerning the Humors, he affirms, that all of them in all Animals are Nutritive, except that in the Allantoides. He observes also, that most of Oviparous Fishes have Eggs or Spawn, as to sense one only colour, and but one humor; yet that the Spawn of a Skate hath a White and a Yolk. Birds have mostly three nutritious substances, that are visible, viz. a Yolk and a double White: to which upon incubation, comes a fourth, colliquated out of the former; the tender Embryo feeding upon the two Whites, till they being consumed, the Yolk of the Chick now to be hatcht, is shut up in the Abdomen, and thence by a peculiar Ductus conveighed into the guts; and so serves the young bird for breasts, it is fed by, until the twentieth day.

In Viviparous Creatures are found sometimes two, sometimes three humors and in Bitches, Cats, and Rabbets four; which perplexeth the Author, as to the giving a reason for it. These Humors, he saith, he hath examined, by concreting, distilling, and coagulating them, where he