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.)]
(2) GRAY OR HOARY POLYPODY
Polypodium incanum. P. polypodioides
Fronds oblong, two to seven inches long, deeply pinnatifid, gray and scurfy underneath with peltate scales having a dark center. Fruit-dots rather small, near the margin and obscured by the chaff.
[Illustration: Gray or Hoary Polypody. Polypodium incanum]
In appearance the gray polypody is much like the common species, as the Greek ending oides (like) implies. In Florida and neighboring states it often grows on trees; farther north mostly on rocks. Reported as far north as Staten Island. It is one of the “resurrection” ferns, reviving quickly by moisture after seeming to be dead from long drouth. July to September. Widely distributed in tropical America. Often called Tree-Polypody.
THE BRACKEN GROUP
Sporangia near or on the margin of the segments, the reflexed portions of which serve as indusia.
1. BRACKEN OR BRAKE