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Updated: May 17, 2025
But with the fresh upheaval and climatic disturbance at the end of the Jurassic, and during the Cretaceous, they spread northward, and replaced the dying reptiles, as the Angiosperms replaced the dying cycads. When they met the spread of the Angiosperm vegetation they would receive another great stimulus to development. They appear in Europe and North America in the earliest Cretaceous.
Palms are so like cycads that we may regard them as the descendants of some cycad type. In the UPPER CRETACEOUS, cycads become rare. The highest types of flowering plants gain a complete ascendency, and forests of modern aspect cover the continent from the Gulf of Mexico to the Arctic Ocean.
What precise degree of cold was necessary to kill the reptiles and Cephalopods, yet allow certain of the more delicate flowering plants to live, is yet to be determined. The vast majority of the new plants, with their winter sleep, would thrive in the cooler air, and, occupying the ground of the retreating cycads and ginkgoes would prepare a rich harvest for the coming birds and mammals.
I also saw in 1866, in Portland, a smaller dirt-bed six feet below the principal one, six inches thick, consisting of brown earth with upright Cycads of the same species, Mantellia nidiformis, as those found in the upper bed, but no Coniferae.
Ferns, with Cycads and leaves of monocotyledonous plants, and some apparently brackish and fresh-water shells, accompany the insects in several places, while in others marine shells predominate, the fossils varying apparently as we examine the bed nearer or farther from the ancient land, or the source whence the fresh water was derived.
Like the birds and mammals they await the coming of a fresh period of cold to give them a decided superiority over the cycads. Botanists look for their ancestors in some form related to the Cordaites of the Coal-forest. The ginkgo trees seem to be even more closely related to the Cordaites, and evolved from an early and generalised branch of that group.
Plant life here was exceedingly beautiful and interesting, especially high up in the mountains, palms, pandanus, cycads, crotons, acalyphas, loranths, aroids, freycinetias, ferns and orchids being strongly represented, and among the latter may be mentioned a fine orange dendrobium and a pink calanthe. I found in flower a celebrated creeper, which Ratu Lala had told me to look out for.
England, and a large part of Europe, was a tranquil blue coral-ocean, the fringes of its islands girt with reefs such as we find now only three thousand miles further south, with vast shoals of Ammonites, sometimes of gigantic size, preying upon its living population or evading its monstrous sharks; while the sunlit lands were covered with graceful, palmlike cycads and early yews and pines and cypresses, and quaint forms of reptiles throve on the warm earth or in the ample swamps, or rushed on outstretched wings through the purer air.
The cycads the botanist would say Cycadophyta or Cycadales, to mark them off from the cycads of modern times formed a third of the whole Jurassic vegetation, while to-day they number only about a hundred species in 180,000, and are confined to warm latitudes.
He does not pretend to trace an exact historical series from the sea-weed to the fern, or from the fern again to the conifers and cycads, and lastly from those families to the palms and oaks, but he, nevertheless, points out that the cryptogamic forms, especially the acrogens, predominate among the fossils of the primary formations, the Carboniferous especially, while the gymnosperms or coniferous and cycadeous plants abound in all the strata, from the Trias to the Wealden inclusive; and lastly, the more highly developed angiosperms, both monocotyledonous and dicotyledonous, do not become abundant until the Tertiary period.
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