IV 
European Ferns. 
examples of this mode of growth, in which the growing end of the rhizome will be seen to be 
always in advance of the last leaf. This is still more the case in the Filmy Ferns ( Hymenophyllum ) 
where the long, slender, prostrate rhizome develops several internodes beyond and before the 
youngest leaf. Most of such stems in our ferns are subterranean, as the common Bracken, the 
Marsh Fern ( Nephrodium The/yptcris), in both of which they are considerably branched, or 
bifurcated, and either smooth or covered with a fine coating of hairs. When above the ground 
they are generally, when young at all events, set with close scaly bodies, usually brownish in 
colour, dry, membranous, and lightly attached ; these are called palece or ramenta, and are con- 
spicuous in the Hare’s-foot Fern. The roots in these creeping species are not connected with 
the bases of the fronds, but come off irregularly from the rhizome ; some Hymenophyllums have 
no roots, but the stems are then covered with absorbent hairs, which perform the same function. 
The internal structure of Fern-stems, though of great interest to the botanist, is not to be 
understood without a long technical description, which would be here quite out of place. The 
accompanying woodcut will show that, even in a large tree-fern with a thick stem, no wood is 
formed, the hard tissues, forming what are known as the fibro-vascular 
bundles, being few in number, large, and separate, and forming a regular 
circle in the soft substance of the stem, but not consolidated into a mass 
of wood. There is also no pith in these stems, nor any separable bark, 
though the outer layers of tissue are sometimes hardened and brown. 
Fronds, or Leaves. — It is to these organs that the name Fern is 
generally given in popular language, and in them a very great diversity 
in form, size, and mode of division is found. There are a few points 
common to all fronds which must, however, be here mentioned. The 
stalk, or petiole, or stipes, is the part which connects the frond with the 
stem, and it is like the foot-stalk of a leaf, either articulated with its 
support or continuous with it : articulated and therefore deciduous fronds 
are rare ; they have been called cremobryoid, whilst the ordinary non-articulated adherent ones are 
termed desinobryoid. The Hare’s-foot and the common Polypody are examples of the first group ; 
and the veteran pteridologist, Mr. John Smith, of Kew, who first noted this distinction, states that 
ferns of the eremobryoid group are endowed with much greater tenacity of life, and are more 
readily grown from spores than those belonging to the desinobryoid section. The frond-stalk 
(stipes) is usually stiff and erect, and is very often covered, especially at the base, with paleae similar 
to those on the caudex ; it is circular or flattened, and on a section it exhibits the fibro-vascular 
bundles* continuous with those in the stem — for each frond is always given off from opposite 
an opening in the meshes of the fibro-vascular cylinder in the stem, and its bundles are con- 
nected with those forming the margin of the opening. The base is often thickened or dilated, 
and, in the species with closely-placed fronds, gives off two or three roots. 
The continuation or upper part of the stipes bearing the blade of the frond is called the 
racliis ; in much-divided ferns the stipes has rather the appearance of a stem, and this is especially 
the case in the Climbing Fern ( Lygodium ), where the rachis is of indefinite length and completely 
simulates a stem. Mr. Darwinf states that these Climbing Ferns do not differ in their habits from 
other twining plants. In Lygodium articulatum the two internodes of the rachis which are first 
* The structure of the stipes of most of the European species is fully described and well figured by M. Duval- 
Jouve, in Billot’s “ Annotations h. la More de France” (1855—62). 
t “ Climbing Plants,” p. 38. 
TRANSVERSE SECTION OF 
STEM OF TREE-FERN. 
