Page:Proceedings of the Royal Society of London Vol 1.djvu/347

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Mr. Brodie was induced to draw up the account of this case, although other instances are already recorded, because the child differed much less from the natural formation than usual.

Twins were produced, both still-born, at the seventh month of pregnancy. The placenta was not preserved; but it was remarked that the chords belonging to the two children were, at their attach- ment, distant about three inches from each other. In one of these children nothing preternatural was observed. The other was dis- tended, and disﬁgured with ﬂuid contained in two cysts under the common integuments of the neck and thorax; but when the ﬂuid was evacuated, the form was nearly natural, with the exception of a hare lip, and a deﬁciency of some of the toes and ﬁngers. In the brain also, and nervous system, nothing unusual was observed. But in the thorax there was no heart, thymus gland, or pleura; and the substances corresponding to lungs, on each side, at the bifur- cation of the trachea, were no more than one third of an inch in dia- meter, the thorax being ﬁlled with a dense cellular substance.

The diaphragm was merely membranous. The stomach had no cardiac oriﬁce; the intestines were shorter than natural; and there was no omentum, no liver, and no gall-bladder.

At the navel entered two vessels, an artery and a vein; the former passing along, with the urachus, to the left groin, gave 03' the ex- ternal and internal iliacs, and then passing upwards, joined the right iliac and became aorta, having the usual branches to the viscera and parietes of the abdomen; and when it reached the upper part of the thorax, it sent off the two subclavian arteries, and then divided into the two carotids, without forming any arch. The course of the veins was equally simple; but its communication with the navel was from the right groin, instead of passing along with the artery on the left side. In the whole course of these vessels there could be discovered no direct communication between the venous and arterial systems, as usual, but merely the union at their capillary extremities, at each termination, in the foetus, and in the placenta; " so that the placenta must have been at once the source and termination of the circulation, and the blood must have been propelled by the action of the vessels only :" and although the circulation, under these circumstances, must be supposed unusually languid, it must be remembered that in this case the whole blood of the foetus was exposed to the inﬂuence of the arterial blood of the mother, instead of that portion alone which usually branches from the general arterlal system.

Various cases (all twins) are next cited by the author, from Mery, from Le Cat, and from Dr. Clarke, of foetuses born without heart; and it is remarked, that all of these were smaller and less perfect than the present subject, which, in fact, was fully equal to the other foetus of the same age with itself, in which the heart was perfect.