(Aborted at twelve or thirteen weeks?)
It is impossible to describe in words, better than Mr. Perry’s pencil has done, the two lovely specimens consigned to this Plate. The drawings speak for themselves. They convey, with a precision which is one of the great merits of that artist, every minute feature of two preparations calculated to afford a fund of knowledge, on the subject of the formative process of the human Ovum, for which we should look elsewhere in vain.
The nutritive involucra are fleshy or coriaceous. Bunches of real hydatids hang pendulous from a part of their external surface—while internally they are lined with the secreting membrane in a morbid state, and that portion of the cord which is farthest from the fœtus appears to be dropsical. The hydatids are connected with the placenta. The fœtus is well formed, and in its growth no impediment seems to have intervened.
REMARKS.
The contrast between this and the preceding Ovum, fig. 17, cannot fail to strike my readers. In the present specimen we have the regular involucra of the Ovum thickened around its whole circumference; but the mossy or filiform vessels have disappeared inside and out, being converted, in the latter situation, into the placenta, and having become obliterated in the former. The placenta (the intervening means of affording accretion of substance to the fœtus by the mother) being once formed, the fœtus grew; but the placenta at last was stricken with disease, (the hydatids,) and this produced the dropsical swelling of the cord, which began to interrupt the growth, and lastly destroyed the life of the fœtus. In Ovum 17, circumstances are reversed. We have no regular placenta; the coriaceous envelopes cover the dropsical bulbs of the filiform vessels, and the growth of the fœtus is consequently checked at the first onset.
Fig. 19. Ovum cum placentâ, nee vasculare, nec plenè cotyledonicâ, sed filiforme. Amnion morbosum.
(Aborted at twelve or thirteen weeks after menstruation?)
Another of the manifold species of deviation from the natural process of growth and development in the human Ovum. By its size I should judge the fœtus to be about fourteen weeks old. About that period the amnion became probably affected, and the life of the child fell a sacrifice to that circumstance. That membrane is translucid and of a brownish colour, thicker than usual, and in parts nearly opaque. Next, (reckoning outwardly,) and separated from the amnion, is another membrane, resembling closely that which lines the outer-shell of a hen’s egg. No filiform vessels appear on either of its surfaces. Between these two membranes a third is distinguishable on the left of the opening made into the Ovum, and the three are very well separated from each other. The filiform vessels which connect the outer or third membrane with the thick envelopes lying over it, are well marked in the drawing. The placenta is amorphous—not local and defined, but general and mossy. The umbilical cord is covered over by its membranes, lies by the side of the fœtus, and is about twice its length, but withered down to a bare filament. Yet the proper fœtus itself is of fair growth and plump.
REMARKS.
One cannot help comparing together the two Ova, thus placed side by side in this Plate. In the figure which represents a larger fœtus, we have a smaller ovum altogether, and a smaller inner cavity; than in the other figure representing a larger Ovum with a larger inner cavity, from which has escaped a smaller fœtus. Yet I hold their respective ages to be the same. This apparent paradox is to be explained by a consideration of the difference of circumstances in which the two Ova were placed. In Ovum 18, the disease was of slow progress; the increase of the fœtus was retarded from the beginning; and its life became extinct after the disorganization of the Ovum had lasted some time: the appearances of the various parts of the Ovum, as pointed out in my explanation of the figure, shew these facts. In Ovum 19 there was nothing in the least analogous. Though the placenta is imperfectly formed; even in its filiform or mossy or primitive texture, it might serve and has served the purpose, of forwarding the nutrition and growth of the fœtus. The disease which destroyed the latter, being of an inflammatory nature, must have been more rapid in its effect. It put an end to life before there could have been time for growth to be much affected.