This condition makes it appear quite possible that the family may be polygenetic.
In the case of the polygenetic class, the idea is necessarily twofold.
We may consider them as colour-giving principles, and so we term them polygenetic colours.
The polygenetic emergence of writing is, in itself, significant in several ways.
In the various colours and dyes we have all phases, and the monogenetic shades almost imperceptibly into the polygenetic.