234 F. W. Oliver. 
the Lower Cretaceous have advanced our knowledge to an 
appreciable extent. 1 
The Mesozoic was the age of the Cycadophytes, with which 
were Conifers, some Ferns and dwindling Lycopsida; in the 
Palaeozoic, besides the Ferns and conspicuous Lycopsida, there are 
two well-marked series of seed-plants, the Cordaiteae and the 
Pteridospermeae. All these spring from the lowest Palaeozoic rocks 
where their earlier history becomes merged in obscurity. 
The old generalisation that the Palaeozoic was the “ age of 
Vascular Cryptogams ” remains true in part only. For whilst the 
cryptogamic status of the Lycopsida has not been seriously under¬ 
mined, the “ Ferns” have mostly gone into solution to crystallise 
out in the form of seed-plants. 
Notwithstanding their antiquity, it is difficult to resist the con¬ 
viction that both these classes of seed-plants had sprung from fern¬ 
like ancestors. The Cordaitese appear to have been the first to 
take advantage of the potentialities of the seed-bearing condition. 
They attained the dimensions of forest trees and massed their 
sporophylls on special reproductive twigs or catkins, features in 
which they have been followed by the more modern and, as many 
suppose, related Coniferse. They do not appear to have survived 
the Palaeozoic epoch and may be dismissed as a highly evolved 
group not directly concerned with the ancestry of the Angiosperms. 
The Pteridospermea:. 
The history of the Pteridosperms is very different. Though 
having in common with the Cordaiteae the same type of seed, they 
retained the habit and much of the anatomy of Ferns. They are 
essentially seed-plants improvised out of Filicinean ancestors and 
have been aptly described as “ Fougbres a graines.” One might 
almost speak here of Spermophytic Ferns as opposed to Crypto¬ 
gamic Ferns. 
The discovery of the group was strangely belated owing to the 
facility with which the seeds were shed. Long ago some of those 
accustomed to handling Coal-Measure fossils seem to have sus- 
spected that there was something anomalous about the “ Ferns,” 
as we may gather from the following passage describing an exhibit 
at the meeting of the British Association at Birmingham (1849):— 
“ R. Austin, Esq., exhibited a specimen of a Fern from the English 
1 Cf. A. C. Seward, New Phytologist, Vol. II., p. 243. 
