It is
said that they are driven out by the disturbance of the waters,
and, although this would hardly explain why they did not spread
again in the tranquil chalk-ocean, we may again leave the point
open.
In the early part of the Cretaceous, however, the Angiosperms
(flowering plants) suddenly break into the chronicle of the
earth, and spread with great rapidity. They appear abruptly in
the east of the North American continent, in the region of
Virginia and Maryland. They are small in stature and primitive in
structure. Some are of generalised forms that are now unknown;
some have leaves approaching those of the oak, willow, elm,
maple, and walnut; some may be definitely described as fig,
sassafras, aralia, myrica, etc. Eastern America, it may be
recalled, is much higher than western until the close of the
Cretaceous period. The Angiosperms do not spread much westward;
they appear next in Greenland, and, before the middle of the
Cretaceous, in Portugal. They have travelled over the North
Atlantic continent, or what remains of it. The process seems very
rapid as we write it, but it must be remembered that the first
half of the Cretaceous period means a million or a million and a
half years.
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