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8 NOTICE OF A FOSSIL LYCOPODIACEOUS FRUIT.
there can be no doubt, considering the group of plants to which they
are related, that they have been obtained from deposits contemporary
with the Coal or lied Sandstone formations.
Eobert Brown, in his memoir, has not given any specific name to
the plant he has described ; but the establishment of its generic value,
and the probability that other forms of the same genus will be found,
induce me to perpetuate the memory of his important observations by
naming this species Triplosporites Brownii.
I ought, in conclusion, to remark, that this very perfect specimen
which I have described probably represents a spike not fully developed.
Two things seem to indicate this : first, the microspores are, iu almost
all the sporangia that contain them, immersed iu an opaque granular
substance in which they show themselves by their transparency, and
which appears like the cellular plasma that surrounds these organs be-
ibre maturity ; second, the vessels which form the very distinct bundles
in the axis of the cone, show only transverse striae or very indistinct
rings, and not the decided lines of adult scalaridiform vessels.
This immature condition has, perhaps, favoured the beautiful pre-
servation of these fossils ; but it is possible, and even probable, that
the microspores and macrospores, when completely developed, would
present some differences, which need not be considered as proceeding
from a really distinct organization. Some of the spores forming the
triple microspore seem already disposed to isolate themselves, and
might, perhaps, take the trigonal form indicated by Dr. Hooker iu the
spores of Lepidostrobus. Some of the macrospores seem also to pre-
sent in the interior a more complicated structure, w'hich may indicate a
tendency towards the appearance on the trigonal summit of the macro-
spores of Isoetes.
New specimens, even simple fragments, but in a diffei'ent stage of
development, may turn up to complete our knowledge ; but now the
existence of gigantic Lycopodiacere, more completely cori"ehited with
living forms of the Order, is indubitably established.