Communication being opened, they emigrated or married strangers and the sexdigitism vanished.

Maupertuis recalls the history of a family living in Berlin whose members had 24 digits for many generations.

One of them being presented with a normal infant refused to acknowledge it.

There is an instance in the Western United States in which supernumerary digits have lasted through five generations.

Cameron speaks of two children in the same family who were polydactylic, though not having the same number of supernumerary fingers.
Smith and Norwell report the case of a boy of fifteen both of whose hands showed webbing of the middle and ring fingers and accessory nodules of bone between the metacarpals, and six toes on each foot.