CREATION BY EVOLUTION
curious flowers and seeds quite unlike those of modern plants. Their many varieties are collectively known as Cordaites, and a restoration of one is shown in Fig. 6. Near the end of the Palaeozoic era we find the coal plants dwindling in number, as a consequence of the changing conditions
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of Permian time, and new types making their appearance, such as cycads and coniferous trees, ancestral to Mesozoic forms. The late Palaeozoic rocks of Australia, India, South Africa, and South America give evidence of widespread glacial ice. The rigors of this time in these regions expelled many of the members of the earlier cosmopolitan flora and introduced a number of new types, known collectively as the Glossopteris flora. (Fig. 7.) The earlier part of the Mesozoic era was a time of widespread seas; the land deposits then laid down contain few fossil plants. The oldest Mesozoic rocks containing a representative flora are those laid down near the end of the Triassic period. In the long time that had elapsed since the Permian epoch many changes had taken place. A few surviving stragglers of the old order lingered on, but many of these older Mesozoic plants were the diversified descendants of the conifers, cycads, and ginkgos, though they included numerous ancestral representatives of most of the modern families of ferns. The Mesozoic has been
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