Early History of Ferns 213 
nearer to the Ferns than to any other group, it must have differed 
widely from the Ferns as we now know them, or perhaps even from 
any which the fossil record has yet revealed to us. 
iii, The Origin of the Higher Cryptogamia. 
The Sub-kingdom of the higher Spore-plants, the Cryptogamia 
possessing a vascular system, was more prominent in early geological 
periods than at present. It is true that the dominance of the Pteri- 
dophyta in Palaeozoic times has been much exaggerated owing to 
the assumption that everything which looked like a Fern really was 
a Fern. But, allowing for the fact, now established, that most of the 
Palaeozoic fern-like plants were already Spermophyta, there remains 
a vast mass of Cryptogamic forms of that period, and the familiar 
statement that they formed the main constituent of the Coal-forests 
still holds good. The three classes, Ferns (Filicales), Horsetails 
(Equisetales) and Club-mosses (Lycopodiales), under which we now 
group the Vascular Cryptogams, all extend back in geological history 
as far as we have any record of the flora of the land ; in the Palaeo- 
zoic, however, a fourth class, the Sphenophyllales, was present. 
As regards the early history of the Ferns, which are of special 
interest from their relation to the Seed-plants, it is impossible to 
speak quite positively, owing to the difficulty of discriminating 
between true fossil Ferns and the Pteridosperms which so closely 
simulated them. The difficulty especially affects the question of the 
position of Marattiaceous Ferns in the Palaeozoic Floras. This 
family, now so restricted, was until recently believed to have been 
one of the most important groups of Palaeozoic plants, especially 
during later Carboniferous and Permian times. Evidence both from 
anatomy and from sporangial characters appeared to establish this 
conclusion. Of late, however, doubts have arisen, owing to the 
discovery that some supposed members of the Marattiaceae bore 
seeds, and that a form of fructification previously referred to that 
family (Crossotheca) was really the pollen-bearing apparatus of a 
Pteridosperm (Lyginodendron). The question presents much diffi- 
culty ; though it seems certain that our ideas of the extent of the 
family in Palaeozoic times will have to be restricted, there is still a 
decided balance of evidence in favour of the view that a considerable 
body of Marattiaceous Ferns actually existed. The plants in question 
were of large size (often arborescent) and highly organised—they 
represent, in fact, one of the highest developments of the Fern-stock, 
rather than a primitive type of the class. 
There was, however, in the Palaeozoic period, a considerable 
group of comparatively simple Ferns (for which Arber has proposed 
