Page:The Works of William Harvey (part 1 of 2).djvu/584

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.
484
ON GENERATION.

it connected with the uterus; there is only at its upper and blunter part a kind of delicate mossy or woolly covering which stands for the rudiments of the future placenta. The inner aspect is smooth and polished, and covered with numerous rami- fications of the umbilical vessels. In the third month this ovum exceeds a goose's egg in size, and includes a perfect embryo of the length of two fingers' breadths. In the fourth month it is larger than an ostrich's egg. All these things I have noted in the numerous careful dissections of aborted ova which I have made.

In the way above indicated do the hind and doe, affected by a kind of contagion, finally conceive and produce primordia, of the nature of eggs, or the seeds of plants, or the fruit of trees, although for a whole month and more they had exhibited nothing in the uterus, the conception being perfected about the 18th, at furthest, the 21st of November, and having its seat now in the right, now in the left horn, occasionally in both at once. The ovum at this time is full of a colliquate matter, transparent, crystalline, similar to that fluid which in the hen's egg we have called the colliquament or eye, of far greater purity than that fluid in which the embryo by and by floats, and con- tained within a proper tunic of extreme tenuity, and orbicular in form. In the middle of the ovum, vascular ramifications and the punctum saliens the first or rudimentary particle of the foetus and nothing else, are clearly to be perceived. This is the first genital part, which, once constituted, is not only already possessed by the vegetative, but also by the motive soul; and from this are all the other parts of the foetus, each in its order, generated, fashioned, disposed, and endowed with life, almost in the same manner as we have described the chick to be produced from the colliquament of the egg.

Both of the humours mentioned are present in the concep- tions of all viviparous animals, and are regarded by many as the excrements of the foetus, one the urine, the other the sweat, although neither of them has any unpleasant taste, and they are always and at all periods present in conceptions, even before a particle of the foetus has been produced.

Of the membranes investing the two fluids, of which there are only two, the outer is called the chorion, the inner the amnion. The chorion includes the whole conception, and ex-