A few words in the language of the modern botanist will show how this vegetation harmonises with the story of evolution. Plants are broadly divided into the lower kingdom of the Cryptogams (spore-bearing) and the upper kingdom of the Phanerogams (seed-bearing). As we saw, the Primary Era was predominantly the age of Cryptogams; the later periods witness the rise and supremacy of the Phanerogams. But these in turn are broadly divided into a less advanced group, the Gymnosperms, and a more advanced group, the Angiosperms or flowering plants. And, just as the Primary Era is the age of Cryptogams, the Secondary is the age of Gymnosperms, and the Tertiary (and present) is the age of Angiosperms. Of about 180,000 species of plants in nature to-day more than 100,000 are Angiosperms; yet up to the end of the Jurassic not a single true Angiosperm is found in the geological record. This is a broad manifestation of evolution, but it is not quite an accurate statement, and its inexactness still more strongly confirms the theory of evolution. Though the Primary Era was predominantly the age of Cryptogams, we saw that a very large number of seed-bearing plants, with very mixed characters, appeared before its close. It thus prepares the way for the cycads and conifers and ginkgoes of the Mesozoic, which we may conceive as evolved from one or other branch of the mixed Carboniferous vegetation. We next find that the Mesozoic is by no means purely an age of Gymnosperms. I do not mean merely that the Angiosperms appear in force before its close, and were probably evolved much earlier. The fact is that the Gymnosperms of the Mesozoic are often of a curiously mixed character, and well illustrate the transition to the Angiosperms, though they may not be their actual ancestors. This will be clearer if we glance in succession at the various types of plant which adorned and enriched the Jurassic world. The European or American landscape--indeed, the aspect of the earth generally, for there are no pronounced zones of climate--is still utterly different from any that we know to-day. No grass carpets the plains; none of the flowers or trees with which we are familiar, except conifers, are found in any region. Ferns grow in great abundance, and have now reached many of the forms with which we are acquainted. Thickets of bracken spread over the plains; clumps of Royal ferns and Hartstongues spring up in moister parts. The trees are conifers, cycads, and trees akin to the ginkgo, or Maidenhair Tree, of modern Japan. Cypresses, yews, firs, and araucarias (the Monkey Puzzle group) grow everywhere, though the species are more primitive than those of today. The broad, fan-like leaves and plum-like fruit of the ginkgoales, of which the temple-gardens of Japan have religiously preserved a solitary descendant, are found in the most distant regions. But the most frequent and characteristic tree of the Jurassic landscape is the cycad.