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only about a dozen have so far failed to yield examples of 

 crested forms to the varietal fern hunter. In many instances 

 the tendency to split up is developed erratically in the form 

 of irregularly branched and tasselled fronds ; while in 

 some cases it so predominates over the normal tendency to 

 produce a flat frond, that the whole fern is a bunch of 

 tassels so closely set as to resemble a ball of moss or 

 selaginella. 



Here, then, is a whole range of frond forms which have 

 no counterpart at all in leaf forms. The extra foliose or 

 plumose type of fern variation, embracing the fringed and 

 frilled section of the Hartstongues cannot be so clearly 

 distinguished from some of the abnormal leaf types, in 

 flowering plants, such as we see in some cyclamen sports, 

 where the fringed or butterfly type of flower is associated 

 with a frilled and fringed edge to the very large leaves. 

 Many of the more beautiful examples of fern variation, 

 however, belong to this section, which superficially may 

 be said to be represented by Todea supevha, though since 

 ferns have been subjected to cultural selection, even that 

 gem of emerald vegetation has been excelled by the divisi- 

 lobe plumosums of Polystichum angulaye, and more recently 

 by those marvels of dissection, Nephvolepis exaltata What- 

 mani and Mavshalli compada. To these extremely dissected 

 and exuberant types we have no parallels in true leaves, 

 although curiously enough, they have been derived from 

 merely pinnate or bipinnate specific forms, which some 

 leaves could easily surpass. 



The most extraordinary example of the twisted type is 

 a form of the Common Bracken, known as Pteris aquilma 

 glomevata, in which all the leafy subdivisions and terminals 

 curl up so tightly as to twist the stalks into knots and form 

 balls, the fronds presenting thus a most weird and unnatural 

 appearance. In the revolute forms the fronds form tubes 

 instead of being flat, and the side divisions are convex, 

 and, together with the frond tip, are spirally twisted owing 

 to the fact that the rolling up of the frond tends to bring 



