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6 NOTICE OF A FOSSIL LYCOPODIACEOUS FRUIT.
regular longitudinal ranges, which are disposed in a very elliptical
helix, whose generating spire would be expressed by the fraction ^,
an arrangement approaching that seen in several living Lycopodiacea*
The scales or bracts whicli form the spike are borne perpendicularly
on the axis, and are even a little reflected ; as they have exactly the
structure so well described by R. Brown in his Triplosporites, it is un-
necessary for me to repeat it. As in his specimen, they take an erect
direction towards their apex, and terminate at the surface of the fossil
in a hexagonal disk, which should, as in LepjicJoslrohns, be prolonged
into a foliaceous appendix, biit this has been destroyed.
On the narrow pedicels of these scales are inserted oblong sporangia,
rounded at their extremities, as in Triplosporites ; those which occupy
the summit and middle portion of the spike are filled with an innumer-
able quantity of little spores, formed of three or sometimes of four
spherical united cellules, which in some cases appear to separate into
simple globular spores.
On the lower portion of the spike we find sporangia similar in form
and in their mode of attachment to the preceding, but which are ob-
viously distinguished from them by the spores which they contain
being simple, spherical, and of a considerable size, their diameter being
ten or twelve times greater than that of the smaller spores. They are
very distinct to the naked eye, their diameter being three-tenths of a
line, and enable one at once to detect the sporangia containing the
microspores.
These larger and perfectly spherical spores have a thick, smooth
covering ; they generally contain scattered globular granules, the na-
ture of which it is difficult to ascertain, but which seem to indicate an
immature state ; some, filled with an opnque matter, appear more ad-
vanced in their development.
This spike thus presents, as in the Lycopodiaceous genera Selaginella
and hoHes, sporangia of two kinds, the one towards the summit con-
taining microspores,—that is to say, antheridia ; the others, placed
towards the base of the spifcp, containing macrospores, or germinating
spores.
The fonn and mode of attachment of these sporangia, their large
size, the great numlicr of microspores they contain, the absence of any
* I bare represented tliis arrangement of tlie leaves oi L^eojwdiacece in the
' Iliitoire cks Vegetaux Fossilcs,' vol. ii. plate ii.
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