There are others, but nothing certain is known about these minor subdivisions.
It may be that a single temple was the resort of several small associations of worshippers which were subdivisions of the whole community.
Five subdivisions may be recognised in the Miocene deposits, corresponding with five different stages in the evolution of southern Europe.
These subdivisions of the larger groups are not necessarily those theoretically approved by the present writer, but they have the valuable sanction of the individual experts who have given special attention to different of the vast field represented by the animal kingdom.'
The following subdivisions have been recognized by Molengraaff Karroo System, Transvaal System, Vaal River System, South African Primary System.