Anomalies and Curiosities of Medicine by George M Gould and Walter L Pyle
Original Copyright 1896 by W.B. Saunders
Now, although it is not safe to say that such an anomaly is impossible, I do not know of any case of this peculiar mode of union; but it may be that, as Prof. A. R. Simpson has suggested, the Maids had four separate arms, and were in the habit of going about with their contiguous arms round each other's necks, and that this gave rise to the notion that these limbs were united. If this be so, then the teratologic difficulty is removed, for the case becomes perfectly comparable with the well-known but rare type of double terata known as the pygopagous twins, which is placed by Taruffi with that of the ischiopagous twins in the group dicephalus lecanopagus.
Similar instances, which are well known to students of teratology, are the Hungarian sisters (Helen and Judith), the North Carolina twins (Millie and Christine), and the Bohemian twins (Rosalie and Josepha Blazek). The interspace between the thoraces may, however, have simply been the addition of the first artist who portrayed the Maids (from imagination ?); then it may be surmised that they were ectopagous twins. "Pygopagous twins are fetuses united together in the region of the nates and having each its own pelvis. In the recorded cases the union has been usually between the sacra and coccyges, and has been either osseous or (more rarely) ligamentous. Sometimes the point of junction was the middle line posteriorly, at other times it was rather a posterolateral union; and it is probable that in the Biddenden Maids it was of the latter kind; and if is likely, from the proposal made to separate the sisters after the death of one, that it was ligamentous in nature. "If it be granted that the Biddenden Maids were pygopagous twins, a study of the histories of other recorded cases of this monstrosity serves to demonstrate many common characters.
Thus, of the 8 cases which Taruffi has collected, in 7 the twins were female; and if to these we add the sisters Rosalie and Josephs Blazek and the Maids, we have 10 cases,of which 9 were girls. Again, several of the pygopagous twins, of whom there are scientific records, survived birth and lived for a number of years, and thus resembled the Biddenden terata. Helen and Judith, for instance, were twenty-three years old at death; and the North Carolina twins, although born in 1851, are still alive. There is, therefore, nothing inherently improbable in the statement that the Biddenden Maids lived for thirty-four years. With regard also to the truth of the record that the one Maid survived her sister for six hours, there is confirmatory evidence from scientifically observed instances, for Joly and Peyrat state that in the case seen by them the one infant lived ten hours after the death of the other. It is impossible to make any statement with regard to the internal structure of the Maids or to the characters of their genital organs, for there is absolutely no information forth- coming upon these points.
It may simply be said, in conclusion, that the phenomenon of Biddenden is interesting not only on account of the curious bequest which arose out of it, but also because it was an instance of a very rare teratologic type, occurring at a very early period in our national history."
