The early botanists who strove to prove that Ferns were, so to speak, the
last development before the Flowering Plants were not, perhaps, very far
from the truth. It has been seen that during the period when the coal
deposits were being formed there flourished side by side races of true
Ferns and Fern-like plants which bore seeds—the Pteridosperms. The point
has also been suggested that in all probability these two groups of
plants had a common origin. With the coming of later times (the
Cretaceous and Jurassic periods) there appeared the Bennettiteæ. These
remarkable plants seem to have entirely taken the place of the
Pteridosperms, and were an enormous advance towards the Flowering Plants
of the present day. Only recently have the Bennettiteæ been properly
described and their interesting features fully understood. We have a few
representatives of this important group in the Cycads, plants bearing a
superficial resemblance to Palms, but actually very different in all
other ways. By the manner in which the reproductive organs are produced,
and the way in which the scheme is carried out, these Bennettiteæ appear
to be a half-way house between the cryptogams and the advanced flowering
plants. The stamens bearing the pollen are produced on the fronds very
much like the sporangia of Ferns. On the other hand, the seed-bearing
structures are collected together into a sort of pistil. This was borne
at the tip of the branches and ended their growth, just as happens in the
case of Flowering Plants. For some reason which we cannot understand
these Bennettiteæ seem to have fallen back in the race for supremacy, for
the group is but poorly represented in our modern Cycads and a few allied
plants. In all the world there are perhaps not more than about a dozen
species, the sole survivors of a race which at one time dominated the
world. There seems every reason for thinking that the Flowering Plants
arose as an offshoot of the Bennettiteæ, and in some way secured an
advantage which enabled them to arrive at their present position.
Public-domain text, read in full here on John Shaqi.
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