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appear to have been uniform all over the world, even as near 
the pole as Spitzbergen. Club-mosses and horsetails were 
trees in bulk and stature, though ungainly to our eyes with 
their angular forked branching, their spiral rows of stiff 
leaves, and their grotesque fructification. Mingled with these 
interesting though unlovely exaggerations were the beautiful 
lace-like fronds of tree-ferns, as well as a thick carpet of 
the lowlier species, and also scattered Cycads and Conifers. 
No birds built their nests in this monotonous jungle, no 
bees, or butterflies lighted up a world destitute of colour 
and fragrance. But life was, nevertheless, abundant in 
these thickets, though of an unattractive kind, molluscs 
and myriapods, and wood-boring beetles. Now, the first 
thing that strikes us in examining the fossil remains of this 
flora is the extraordinary abundance and perfection of the 
impressions of ferns. ‘Their state of preservation is often 
marvellous. It should be remembered also by those who 
only see them in cabinets that those collected are but a fraction 
of those noticed by the observant naturalist. Very often the 
shale in which they lie buried is so brittle that the collector 
only catches a passing glimpse of a lovely impression before 
the matrix crumbles to pieces as he tries to grasp it. It seems 
impossible, in the face of this abundance of remains, to deny 
that at any rate we have here a fairly complete record of local 
floras. So far as it goes it canbe trusted. As the date of the 
palzozoic coal measures must in any case be very remote, they” 
evidently supply us witha crucial testfor the Theory of Descent. 
If that theory were true, the lines of vegetable pedigree should 
be at that time visibly converging. For instance, the three 
great classes of Vascular Cryptogams ought to be far nearer to 
each other then than they are now. Is this the case? Noto- 
riously the answer is in the negative. Ferns, horsetails, and 
club-mosses are not only not converging, but are, if anything, 
further removed from each other than now. The two latter 
groups then reached their culminating point both in the size 
of individuals, the number of genera, and the complexity of 
structure. The Lepidodendrons and Sigillarias had a kind of 
woody structure feebly represented in their present herbaceous 
representatives. So also had the huge Calamites, Calamoden- 
drons, and Equisetites, which have now dwindled down to a 
solitary ¢ genus, Hquisetum. The peculiar spores of many of the 
fossil genera are found in vast abundance, and proclaim unmis- 
takably their affinity to the modern sur vivals. 
The ferns still flourish, but at that period they were 
evidently of greater relative importance than now. At 
present about forty species grow in the British Islands, but 
