Page:The Works of William Harvey (part 1 of 2).djvu/521

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ON GENERATION.
421

instance, without lips, the mouth gaping, and extending from ear to ear.

Many women, whose conceptions, like the wind-eggs of fowls, are barren and without an embryo, miscarry in the third month. I have occasionally examined aborted ova of this age, of the size of a goose's egg, which contained embryos distinct in all their parts, but misshapen. The head, eyes, and extremities were distinct, but the muscles were indistinct ; there were no bones, but certain white lines in their situations, and as it seemed, soft cartilages. The substance of the heart was ex- tremely white, and consisted of two ventricles of like size and thickness of walls, forming a cone with a double apex, which might be compared to a small twin-kernel nut. The liver was very small and of the general white colour. Through the whole of this time, i. e. during the first three months, there is scarcely any appearance of a placenta or uterine cake.

In every conception of this description I have seen, I have always found a surrounding membrane containing a large quan- tity of watery fluid, between which and the body of the embryo, suspended by its middle by means of a long and twisted um- bilical cord, there is such disproportion, that it is impossible to regard this liquid as either sweat or urine ; it seems far more probable that like the colliquament in the hen's egg, it is a fluid destined by nature for the nourishment of the foetus. Nor was there any indication to be discovered of these concep- tions or ova having been connected with the uterus ; there was only on the external surface of their larger extremity a greater appearance of thickening and wrinkling, as if the rudiments of the future placenta had existed there.

These conceptions, therefore, appear to me in the light of ova, which are merely cherished within the uterus, and, like the egg in the uterus of the fowl, grow by their own inherent powers.

In the fourth month, however, it is wonderful to find what rapid strides the foetus has made : from the length of the thumb it has now grown to be a span long. All the members, too, are distinct and are tinged with blood ; the bones and muscles can be distinguished ; there are vestiges of the nails, and the foetus now begins to move lustily. The head, however, is excessively large ; the face without lips, cheeks, and nose ; the gape of the