Natural Selection 217 
majority of the supposed Ferns of that age having proved to be seed- 
bearing plants. The oldest authentic representatives of the Ferns 
were megaphyllous plants, broadly speaking, of the same type as 
those of later epochs, though differing much in detail. As far back 
as the record extends they show no sign of becoming merged with 
other phyla in any synthetic group. 
The Equisetales likewise have a long history, and manifestly 
attained their greatest development in Palaeozoic times. Their 
oldest forms show an approach to the extinct class Sphenophyllales, 
which connects them to some extent, by anatomical characters, with 
the Lycopods. At the same time the oldest Equisetales show a 
somewhat megaphyllous character, which was more marked in the 
Devonian Pseudoborniales. Some remote affinity with the Ferns 
(which has also been upheld on other grounds) may thus be indicated. 
It is possible that in the Sphenophyllales we may have the much- 
modified representatives of a very ancient synthetic group. 
The Lycopods likewise attained their maximum in the Palaeozoic, 
and show, on the whole, a greater elaboration of structure in their 
early forms than at any later period, while at the same time maintain- 
ing a considerable degree of uniformity in morphological characters 
throughout their history. The Sphenophyllales are the only other 
class with which they show any relation; if such a connection existed, 
the common point of origin must lie exceedingly far back. 
The fossil record, as at present known, cannot, in the nature of 
things, throw any direct light on what is perhaps the most disputed 
question in the morphology of plants—the origin of the alternating 
generations of the higher Cryptogams and the Spermophyta. At the 
earliest period to which terrestrial plants have been traced back all 
the groups of Vascular Cryptogams were in a highly advanced stage 
of evolution, while innumerable Seed-plants—presumably the descend- 
ants of Cryptogamic ancestors—were already flourishing. On the 
other hand we know practically nothing of Palaeozoic Bryophyta, 
and the evidence even for their existence at that period cannot be 
termed conclusive. While there are thus no palaeontological grounds 
for the hypothesis that the Vascular plants came of a Bryophytic 
stock, the question of their actual origin remains unsolved. 
IIL NatTurRAu SELECTION. 
Hitherto we have considered the palaeontological record of 
plants in relation to Evolution. The question remains, whether 
the record throws any light on the theory of which Darwin and 
Wallace were the authors—that of Natural Selection. The subject 
is clearly one which must be investigated by other methods than 
