This species has a creeping root-stock which in its young days is covered with brown scales. From the underside there grow masses of fibrous roots, which often spread for a considerable distance. The rhizome may be very much branched, and from it alternately on either side arise the fronds. These may be quite short—about five or six inches—or, on the other hand, they may be as much as one or two feet in length. The stipes is usually about the same length as the leafy portion of the frond and is of a plain green colour. The general outline of the leafy part of the frond is lanceolate, tapering to a point, broad in the centre and narrowing slightly at the base. The frond of the Common Polypody is cut in a pinnatifid manner. The lobes, which are more or less rounded at the tip, are separated by openings in which the leafy portion is cut almost down to the rachis. Now and again the margin of the lobes is somewhat toothed. [Illustration: Polypodium vulgare. The Common Polypody.] On the back of the frond are to be found the sori. These are disposed on both sides of the mid-ribs of the lobes; they are circular in shape and have no indusia or covering of any kind. When the sporangia are young the sori are of a very pale yellow colour; this changes to a rich golden-brown as the capsules mature. The sori are mostly confined to the upper portion of the frond, and on account of their bright colouring add very much to the appearance of the leaf. There are a large number of varieties of the Common Polypody. [Illustration: Enlargement of the sori on the frond of Common Polypody.] The Common Polypody will, of course, grow in almost any position. It often finds a home amongst the branches of old oak trees, whilst it seems to be equally happy on the wall or the hedge-bank. It is of fairly easy culture in the garden, though the plant likes a well-drained situation. The Common Polypody is an evergreen species. [Illustration: Polypodium phegopteris. The Beech Fern.] _Polypodium phegopteris._ Here the specific name is formed of two Greek words—_phegos_, “a beech,” and _pteris_, “a fern.” This is, of course, a rendering of the popular name, though why the species has been called the Beech Fern nobody seems to know. Certainly the species is not like a Beech, neither can it be said to grow in association with this tree. The Beech Fern or Mountain Polypody. This species has a slender creeping rhizome from which arise the dainty light green fronds. The fronds vary from about six inches to a foot in length; the stipes is longer than the leafy portion, and is of a light green colour. The outline of the leafy part is triangular in form, and on either side of the rachis are the tapering pinnæ. At the top the frond is pinnatifid, whilst the lower pinnæ are deeply cut. A very distinctive feature of the Beech Fern is the way in which the lower pair of pinnæ point downwards away from the tip of the frond.