y (_Trichomanes_) has the spore cases along
a bristle-like receptacle and surrounded by an urn-shaped, slightly
two-lipped involucre; ring transverse and opening vertically (Fig. 7).

[Illustration: Fig. 5]

[Illustration: Fig. 6]

[Illustration: Fig. 7]

THE FERN FAMILY PROPER OR REAL FERNS

_POLYPODIACEAE_

Green, leafy plants whose spores are borne in spore-cases (sporangia),
which are collected in dots or clusters (fruit-dots or sori) on the back
of the frond or form lines along the edge of its divisions. Sporangia
surrounded by vertical, elastic rings bursting transversely and scattering
the spores. Fruit-dots (sori) often covered, at least when young, by a
membrane called the indusium. Spores brown.

THE POLYPODIES

1. POLYPODY. _Polypodium_

(From the Greek meaning many-footed, alluding to the branching rootstocks.)

Simple ferns with stipes articulated to the creeping rootstocks, which are
covered with brown, chaffy scales. Fruit-dots round, naked, arranged on the
back of the frond in one or more rows each side of the midrib. Sporangia
pedicelled, provided with a vertical ring which bursts transversely. A
large genus with about 350 species, widely distributed, mostly in tropical
regions.

(1) COMMON POLYPODY. _Polypodium vulgare_

Fronds somewhat leathery in texture, evergreen, four to ten inches tall,
smooth, oblong, and nearly pinnate. The large fruit-dots nearly midway
between the midrib and the margin, but nearer the margin.

[Illustration: Common Polypody. _Polypodium vulgare_]

Common everywhere on cliffs, usually in half shade, and may at times spring
out of decaying logs or the trunks of trees. As the jointed stipes, harking
back to some ancient mode of fern growth, fall away from the rootstocks
after their year of greenness, they leave behind a scar as in Solomon's
seal. The polypody is a gregarious plant. By intertwining its roots the
fronds cling together in "cheerful community," and a friendly eye discovers
their beauty a long way off. August. Abounds in every clime, including
Europe and Japan.

In transplanting, sections should be cut, not pulled from the matted mass.

Var. _cambricum_ has segments broader and more or less strongly toothed.

Var. _cristatum_ has the segments forked at the ends.

Several other forms are also found.

[Illustration: Fruited Frond]

[Illustration: The Common Polypody. _Polypodium vulgare_ (Photographed by
Miles Greenwood, Melrose, Mass