R fl
fi: f?1-'
'
are supported on shaggy stipes of about a third of their
entire length.
The fronds have a strong midrib or costa, extending
throughout their whole length, from which are produced
forked veins, the branches of which (venules) lie paraUel,
and proceed direct towards the margin, terminating just
within the edge in a club-shaped apex. The veins are usually
forked twice, but they are not constant to any exact number
of divisions. The sori, which are oblong patches of
unequal length, lying in the direction of the veins at short
intervals along the upper two-thirds of the length of the
frond, are each composed of two proximate lines of fructification
laterally united; each of these lines, however, consisting
of a complete sorus, so that the two united are properly
called a twin sorus. This is the mark of the genus Scolo-
penirium. This twin sorus is always produced between two
fascicles of veins; that is, the lowermost venule produced by
one vein, and the uppermost venule produced by the vein
next below—these two venules lying, of course, contiguous,
each become the receptacle upon which a line of spore-cases
is produced. The indusia which cover these two lines of
spore-cases have their attachment respectively on the upper
and lower sides of their venules, the other edges overlapping
SCOIOPENDRIHM.
one the other; the free margin, therefore, is exterior wi
reference to the fascicle of venules to which it belongs,
m e n very young there is no evident trace of separation at
the part where they overlap, but as they advance towards
maturity the separation becomes apparent, and they eventually
open down the centre, one indusium turning upwar s
and the other downwards, the two Unes of spore-cases
they had covered becoming confluent and undistinguishable
without manipulation.
This is the ordinary form of Scolopendrium; but there are
some ver, corioo. amd distinct cmieties, differing only,
however, in the form of the fronds, and not in the fructification,
where it is present. Of these varieties it is deserving
of especial mention that they are perfectly constant under
cultivation, although they have, no doubt, originated in
aberrations, that is to say, accidental variations of the original
species, which have been perpetuated either naturally
or by art. , „ . .
The most beautiful of these varieties is that caUed cmpum,
in which, while the same outline of frond prevails,
yet the leafy portion is so much more developed than the
midrib, that the margin becomes excessively undiJated,
giving the fronds a very elegant curled or crisped apm
I '