Links With the Past in the Plant WorldSeward, A. C. (Albert Charles)
Science
Links With the Past in the Plant World
Seward, A. C. (Albert Charles)
Paleobotany -- Great Britain; Plants -- Great Britain
A few years ago Prof. Bommer discovered fragments of leaves and
stems in Wealden beds a few miles from Brussels sufficiently well
preserved to reveal the details of internal organisation. Some of
these fossils were found to possess structural features identical
with those of the Malayan species of Matonia. A full account of the
fossil representatives of the Matonia family would be out of place in
a general essay on Links with the Past, but brief reference may be
made to some of the data which throw light on the geological history
of the family. In strata classed by geologists as Rhaetic, a phase
of earth-history between the Triassic and Jurassic eras (see p. 42),
species of Laccopteris and allied forms have been described from
several other countries; from Jurassic and Wealden strata examples of
both Laccopteris and Matonia have been found in Germany, Portugal,
Belgium, Austria, and elsewhere. From rocks of Cretaceous age, higher
in the series than the Wealden strata, well preserved impressions of a
Matonidium have been discovered in Moravia. The Matonineae were widely
distributed in Europe during the Rhaetic and Jurassic periods, but, so
far as we know, the family did not survive in the northern hemisphere
beyond the limits of the Cretaceous period. It is noteworthy that, in
spite of the preservation of the remains of Jurassic and Cretaceous
floras in many extra-European regions, notably in India, South Africa,
Australia, China, and Tonkin, no specimens have been found which can
with confidence be assigned to the Matonineae. A single fossil has,
however, been described from Queensland which may be a piece of a
Laccopteris frond.
There is some evidence that ferns very similar to Matonia existed
in North America during the Mesozoic period. It would be in the
highest degree rash to assume that the Matonineae played no part in
the Jurassic vegetation of India, South Africa, and other southern
lands, but there can be little doubt that the family was especially
characteristic of European floras during a portion of the Mesozoic era.
It would seem that subsequent to the Wealden period the ancestors of
Matonia dwindled in numbers and their geographical range became much
more restricted.
The records of Tertiary rocks have hitherto added nothing to our
knowledge of the distribution of the family subsequent to the
Cretaceous period. All we can say is that the existing species of
Matonia are the last survivors of a family which in the Jurassic period
overspread a wide area in Europe and probably extended to the other
side of the Atlantic. Exposed to unfavourable climatic conditions and
possibly affected by the revolution in the plant world consequent
on the appearance of the Flowering Plants, the Matonineae gradually
retreated beyond the equator until the two surviving species found a
last retreat in the Malayan region.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account