volcanic and coral islands of the modern Pacific.
The seed thus stranded upon new formed land,
produces a plant which has peculiar provision for
its support on a surface destitute of soil, by long
and large aerial roots protruded above the ground
around the lower part of its trunk. (See PI- 63.
Fig. 1.) These roots on reaching the ground
are calculated to prop up the plant as buttresses
surrounding the basis of the stem, so that it
can maintain its erect position, and flourish in
barren sand on newly elevated reefs, where little
soil has yet accumulated.
We have as yet discovered no remains of the
leaves, or trunk of Pandaneae in a fossil state, but
the presence of our unique fruit in the Inferior
Oolite formation near Charmouth, carries us back
to a point of time, when we know from other
evidence that England was in the state of newborn
land, emerging from the seas of a tepid climate
; and shews that combinations of vegetable
structure such as exist in the modern Pandaneae,
adapted in ,a peculiar manner to the office of
vegetable colonization, prevailed also at the time
when the Oolite rocks were in process of formation.
This fruit also adds a new link to the chain of
evidence, which makes known to us the Flora of
the Secondary periods of geology, and therein
discloses fresh proofs of Order, and Harmony,
and of Adaptation of peculiar means to peculiar
ends ; extending backwards from the actual condition
of our Planet through the manifold stages
of change, which its ancient surface has undergone.*
SECTION IV.
VEGETABLES IN STRATA OF THE TERTIARY SER IE S . f
It has been stated that the vegetation of the
Tertiary period presents the general character
of that of our existing Continents within the
Temperate Zone. In Strata of this Series,
Dicotyledonous Plants assume nearly the same
proportions as at present, and are four or five
times more numerous than the Monocotyledo-
nous; and the greater number of fossil Plants,
although of extinct species, have much resemblance
to living Genera.
This third great change in the vegetable kingdom
is considered to supply another argument in
favour of the opinion, that the temperature of
the Atmosphere, has gone on continually diminishing
from the first commencement of life upon
our globe.
* Fruits of another genus of Pandanese, to which Mr. Ad.
■Brongniart has given the name.of Pandanocarpuni, (Prodrome,
p. 138,) occur together with fruits of Cocoa nut, at an early-
period of the Tertiary formations, among the numerous fossil fruits
that are found in the London-clay of the Isle of Sheppey.
+ See PI. 1, T'igs. 06 to 72.