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NOTICE OF A FOSSIL LYCOFODIACEOUS FRUIT. 5
The numerous spikes of fructification—many of tliem, however,
very imperfectly preserved— examined by this excellent observer are
often very small portions of the cones ; some of them, however, seem
to have been preserved in full, and there is no indication of difference
of structure between the base and summit. All the scales bear spo-
rano^ia of the same form, which appear to enclose bodies of the same
nature ; this is, at least, what the figures and descriptions published by
the learned English botanist indicate.
These characters seem, then, to place Lepidontrobus among true
Lycopodia, the sporangia of which are all alike, and enclose similar
spores.
The family of Lycopodiacece contains two other genera very different
in this respect, Selagiuella and Isolates, which, on the same stem or in
the same spike,—that is to say, on the same axis,—have two kinds of
sporangia, the one containing very small spores destined to j)roduce
antherozoids, and to become fecundating organs ; the other much
larger spores, which germinate after being fecundated. These two
organs have been designated by the names of miorospofes and macro-
spores.
There is nothing in the specimens described by R. Brown, or by Dr.
J. Hooker, which indicates this double nature of the sporangia and
spores ; but a very perfect and on the whole well-preserved specimen
of a spike, identical in its upper part with the Triplosporites of R.
Brown, throws a new light on this subject, and shows a modification
in these points analogous to what we observe in living Lycopodiacece.
This remarkable specimen was found in the drift at the entrance
of the valley of Volpe, in Haute-Garonne, by M. Dabadie, apothe-
cary ;
it was given to me by M. Lartet, to whom M. Dabadie had en-
trusted it, and the discoverer of this interesting specimen has been
good enough to allow me to make a longitudinal section of it, and to
keep the half of it for the Museum.
This specimen, of which a cast was carefully taken before being cut,
is completely silicified ; the organization of the different parts is well
preserved in many points ; but the anfractuosities and the crystallized
parts do not allow an equally complete examination throughout.
It is a cone or cylindrical strobilus, 4 inches 8|- lines long, and
2 inches If lines broad, showing on the exterior the summits of the
scales of which it is composed ; these form twenty-seven perfectly