HISTORY OP BRITISH PERNS.
sidered as pollen by some, and as abortive spores by others.
The other kind of spore-case contains three or four roundish
fleshy bodies, which are marked at the apex by a three-
branched line, and are many times as large as the granular
bodies wliich have been already mentioned. These larger
bodies have been called spores or oophoridia, and by some
observers anthers.
The true explanation of these parts is a matter of doubt.
All that is certainly known is, that the larger bodies do
germinate, or at least vegetate, and according to a statement
of Willdenow the smaller ones germinate also. It seems
probable that the suggestion made by Dr. Lindley is correct,
namely, that the powder-like grains are true spores, while
the large ones are buds or viviparous organs. This view is
supported by the descriptions which have been given of the
supposed germination of these larger bodies, in which a
process quite analogous to the vegetation of a bud is clearly
pointed out.
The granular matter is produced by aU the species of
Lycopodium, but the large fleshy bodies are found only in a
few of the species. It has been usual to regard both sets
of organs, when present, as axillary to the leaves or bracts,
and so they may be considered for all practical purposes.
A different theoretical explanation has, however, been given
by Muller, a German writer, who considers the oophoridium
as the entire metamorphosed terminal bud of a main axis;
and he supports this opinion by the statement that in the
early condition this oophoridium is opposite the spike in
which the granular bodies are produced. The spike and
the oophoridium are by him regarded as two metamorphosed
branches into which a main axis has become divided, and it
is only at a later period of growth that they both appear to
belong to the same axis. The smaller granules, or antheridia,
he regards as lateral buds, or twig buds, only to be distinguished
from the terminal bud which is developed into
the oophoridium, by the circumstance that the latter is a
principal branch, possibly capable of a more extensive development
into branch and foliaceous organs, while the
twig, which is developed into an antheridium, is but a small
particle of such a main branch.
These plants, like the Eerns, are most abundant in hot,
humid, and especially insular, situations in the tropics, becoming
scarcer northwards, but often even in very northerly
regions covering large tracts of land. Our native species,
with one exception, have a boreal and alpine tendency, being
found most abundantly on the high lands of the north, and
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