

СНАРТЕК ТХ 
TYPES ОЕ VARIATION 
IN the foliage of flowering plants there is immense diversity of form, 
both specific and varietal, but in Ferns it would almost appear that, 
prevented by their absence of obvious flowers from displaying 
their powers of variation in that direction, they have made up for it 
by doing so in a very wonderful and surprising fashion in their 
foliage. Between the forms of fronds of diverse genera we naturally 
find great differences, but it is in the case of our native Ferns 
especially that one and the same species has proved itself capable 
of assuming hundreds of different types of fronds, and this not due 
to any human selection at all, but solely to some natural impulse 
to which we have absolutely no clue. Naturally the study of these 
types, despite their multiformity, shows them to permit of some 
classification, and they may be broadly divided into two sections, 
viz. those in which the terminal points of the fronds and sub- 
divisions branch in such a way as to form tassels or crests (cristate), 
and those in which the normal extent of subdivision is increased 
or diminished. Thus a once divided or pinnate form may possibly 
yield a quadri- or quinque-pinnate one, i.e. four or five times divided, 
in this way, practically losing all similarity to the specific and 
simpler type, while in rarer cases a normally divided frond may 
not be divided at all, but become simply strap-shaped. The for- 
mation of terminal tassels is the most prevalent type of abnormality, 
and has been found to occur in a very large number of species 
both native and exotic. No cresting proper has been remarked in 
the foliage of any flowering plant. In the Celosias, or Cockscombs, 
and many other cases of fasciation, there is a similarity, but also 
a fundamental difference. In fasciation we find a multiplication of 
growing points, which develop so closely together as to coalesce, 
a normally round stem thus becoming a flat, or almost ribbonlike 
one, or, ав in the Cockscomb, a dense Cactus-like mass built up 
of innumerable conjoined branches and flower stalks massed solidly 
together. The typical Fern crest, on the other hand, commences to 
develop on what may be considered a normal stalk or midrib, the 
growing point of which, at a certain stage in this development, and 
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