The fossil plants which are found in the upper beds of the preceding Devonian system are so closely related to those in the Lower Carboniferous, that from a palaeobotanical standpoint the two form one indivisible period.
The application of the important criteria which Bower has thus pointed out to the construction of a strictly phylogenetic classification of the Filicaceae cannot be made until the anatomy, the sexual generation and the palaeobotanical evidence have been further examined from this point of view.
Before considering the results of palaeobotanical research, some account must be given of the way in which the evidence is presented, or, in other words, of the modes of preservation of vegetable remains.
Palaeobotanical literature contains several records of species of -Lycopodites and Selaginellites; Lycopo- nearly all of them are sterile fragments, bearing a more diates.
As a definite instance a short review may be given of the evidence of palaeobotanical records as regards their bearing on plant-evolution.