The chorion, in this instance, is thickened nearly as much as the cortex Ovi. A considerable space intervenes between those two involucra; and within this thickened chorion a false membrane is distinctly seen to surround the Ovum. The embryo is advanced to about the third month, but retarded in its growth.
A specimen, analogous to the present, was deposited in 1817, by Mr. Lawrence, in the Museum of the Royal College of Surgeons of London, where it is to be seen marked 3437 C. The involucra are coriaceous, but we have besides, over the nutritive membrane (chorion), not fewer than three false membranes, the result of uteritis post conceptionem. The fœtus has evidently been stinted in its growth, and in size resembles a small insect.
REMARKS.
Instances of additional or pseudo membranes in aborted Ova are by no means of unfrequent occurrence. On one of the shelves in the Museum in Lincoln’s Inn Fields, I observed one marked 3443, in which a pseudo membrane has formed externally to the placenta, pressing on the cotyledons of the latter. The embryo is stinted. Upon another shelf I find No. 3442, with the nutritive as well as the secreting (amnion) involucrum thickened and pergamenous—the coat which they form being one twentieth part of an inch in thickness. The amnion, internally, is lined with a delicate pseudo-membrane. Here, also, although the entire Ovum is of such capacity as to admit about half a pint of fluid, the embryo has not acquired more than the size of an ordinary house-fly. The placenta is compressed and covered by an adventitious membrane, besides its membrana propria.
In Ruysch’s Thes. Anat. VI. Tab. II. Fig. 5, there is represented a specimen of human Ovum, with a pseudo inter-membrane, not unlike my present preparation; like it, too, it exhibits the cord hydropical.
Fig. 17. Ovum uviforme.
(In the third month after the suspension of the menses.)
A uviform abortion is so rare an occurrence that when Mr. Clift first saw the figure of it in the present work, he remarked that it appeared more pictorial than true. The preparation, however, of the size of the design, and as it was sketched by Mr. Perry in 1827, is still in my possession, and I hold it to be most valuable on many accounts.
Under a shower of minute grape-like or granular bunches, is seen suspended that portion of a transparent Ovum, (exhibiting through its diaphanous involucra an embryo bearing no proportion to the magnitude of the Ovum,) which has been denuded of its nutritive involucra. The latter are superimposed to the granular bunches, and are curiously fringed at their margins. They are two in number, and externally to them may be seen the loosely weaved caducous membrane. During three months of utero-gestation, from the moment of conception, has this mass lived—but the embryo has not advanced from what it was at four or five weeks, nor could it. The time was spent by Nature in playfully modelling, forming, and cutting out what would almost appear an artificial plaything; so fantastical it looks.