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not only to dwarf the central one by competition at the roots, 
but spoils the graceful effect afforded Бу an individual centre, 
owing to the intermingling and consequent distortion of the frond- 
age. In addition to these offset-forming buds, a number of our 
abnormal Ferns, and especially the soft Shield Fern (Polystichum 
angulare), produce bulbils, or small plants, on their fronds. In 
most instances these are confined to the lower part of the frond, 
where they appear as brownish scaly knobs within, or close to, 
the axils of the lowest side divisions or pinna. In some instances, 
however, as in the “proliferum” section of this species, such bulbils 
are produced in profusion, even to the very tip of the frond, and 
for some distance up the lateral pinnae as well, so that a dense, 
moss-like growth occupies the centre of the frond, and consists of 
many scores of young plants. Each of these bulbils, while still 
attached, is nourished by the parent plant; but if such a frond be 
detached, pegged down on good compost, either in its entirety 
or in short sections, and kept close, the bulbils will root into the 
soil and produce fresh fronds, and in course of time the connecting 
midrib may be cut apart by scissors or a sharp knife, and a large 
batch of independent plants thereby secured. Where such bulbils 
are few and close to the base, it is better to peg down the frond 
which bears them and let them root in ¿z situ, only removing them 
when well established. In some rare cases bulbils are produced 
on the frond backs in association with the spore heaps; but 
although this occurs as a specific character in one exotic, Lastrea 
prolifera, it has so far only been noted as a varietal feature on 
several plumose Lady Ferns, Athyrium filix femina plumosum 
divavicalum, Axminsterense, and its progeny, the superbum section 
(see chapter on “Fern Selection," р. 29), and some others of the 
same class, and also in one or two cases referred to hereafter. 
Here, however, we are dealing with deciduous Ferns, the fronds 
of which perish in the autumn, and hence such bulbils can only 
occasionally be induced to persist long enough to root when layered 
as described. Much depends on the season. In some years these 
bulbils have appeared so early that by the autumn their fronds 
have formed an obvious fringe to the parent ones, and were easily 
rooted before the latter began to fade. Polypodium vulgare 
elegantissimum also, under very favourable circumstances, pro- 
duces bulbil plants also in conjunction with its spore heaps, but 
only on its most finely cut fronds, and as a secondary growth in the 
second year. Adiantum capillus veneris vars. daphnites and im- 
bricatum both produce bulbils by spore transformation on the 
frond margins, and with a little warmth can be easily propagated 
by their means. Several forms of the Hartstongue (Scolopendrium 
vulgare) are proliferous, sometimes, as in S. v. cristatum viviparum 
O'Kelly, the surface of the frond is dotted with little clusters of 
young plants. In S. v. Wardit, Coolingii, Kelwayii, and Cousensti, 


