PRESENT POSITION OF PALEOZOIC BOTANY—SCOTT. 373 
as Cryptogamic. The Spermophyta of the Paleozoic period consisted 
on the one hand of well-characterized Gymnosperms, and on the other 
of a great assemblage of fern-like forms, resembling the contemporary 
Gymnosperms as regards their seeds, but separated from them by 
the primitive character of their general organization; they may be 
treated as a distinct class—the Pteridospermeex. In addition to Gym- 
nosperms and Pteridosperms, the ranks of Paleozoic “ seed-bearing 
plants ” were further recruited from a different source, the Lycopo- 
diales, some members of which, as recent investigation has shown, had 
made a great advance in the Spermophytic direction, producing 
organs closely analogous with true seeds. 
The division of vascular plants into Spermophyta and Pterido- 
phyta, though sanctioned by botanical usage, ceases to afford a natural 
line of cleavage when we are concerned with Paleozoic vegetation. 
A large proportion of the seed plants of that period were, until 
recently, classed as Ferns, and though their position has changed 
there is no doubt that the affinity between the Pteridosperms, as 
we now call them, and the Ferns was far closer than that between 
the Ferns and any other known group of Pteridophyta. Further, 
the Lycopods above referred to, which were reproduced by means of 
seed-like organs, were in all other respects as true Lycopods as any 
of their purely Cryptogamic allies. 
Hence we have to seek some other line of separation, if we wish, 
on grounds of convenience, to group the Paleozoic Vasculares under 
two main divisions. 
As a provisional scheme, we may adopt Professor Jeffrey’s pro- 
posed division of the vascular plants into Lycopsida and Pteropsida, 
the former including Sphenophyllales (as here limited, a wholly Pale- 
ozoic class) Equisetales and Lycopodiales, while the latter embrace 
the Filicales and the whole of the Flowering Plants. 
The characters on which Professor Jeffrey mainly relied as dis- 
tinguishing his two main groups are three: The Lycopsida are typ- 
ically microphyllous, the Pteropsida megaphyllous; the Lycopsida are 
“ cladosiphonic,” the Pteropsida “ phyllosiphonic,” i. e., the hollow 
vascular cylinder (when present) is interrupted in the former only 
by the exit of branches, forming vamular gaps, in the latter by the 
exit of leaf traces, forming foliar gaps; lastly, the Lycopsida are 
characteristically strobiloid as regards their fructification, while in 
the Pteropsida strobili, or cones, appear only in the higher members 
of the division (Phanerogamia). These characters are by no means 
constant, and are open to much criticism; the general grouping has, 
however, sufficient claims ta be a natural one to afford at any rate 
a basis for the discussion of affinities. 
