The Fern Lover's Companion Part 6

Fronds two to six inches long, triangular-ovate, acute, broadest at the base, tripinnate. Stalks tufted, wiry, shining, dark brown. Upper surface of the very small segments green, smooth, the lower densely coated with a pure, white powder; hence, the specific name _dealbata_, which means whitened. Sori brown at length; veins free.

There are several species of cloak ferns, but only one within our limits.

The dry, white powder which covers them doubtless is designed to protect them from too rapid evaporation of moisture, as they all inhabit dry and sunny places. This delicate rock-loving fern is found in the clefts of dry limestone rocks in Missouri, Kansas, Colorado, and southwestward.

THE CHAIN FERNS. _Woodwardia_

Large and somewhat coa.r.s.e ferns of swampy woods with pinnate or nearly two-pinnate fronds, and oblong or linear fruit-dots, arranged in one or more chain-like rows, parallel to and near the midribs. Indusium fixed by its outer margin to a veinlet and opening on the inner side. In our section there are two species. (Named for Thomas J. Woodward, an English botanist.)

[Ill.u.s.tration: Powdery Cloak Fern. _Notholaena dealbata_ (Kansas) (G.E. Davenport)]

[Ill.u.s.tration: The Common Chain Fern.

_Woodwardia virginica_]

(1) THE COMMON CHAIN FERN. _Woodwardia virginica_

Sterile and fertile fronds similar in outline, two to four feet high, once pinnate, the pinnae deeply incised with oblong segments. Fruit-dots oblong in chain-like rows along the midrib both of the pinnae and the lobes, confluent when ripe. Veins forming narrow rows of net-like s.p.a.ces (areoles) beneath the fruit-dots, thence free to the margin. The spores ripen in July.

The sterile fronds resemble those of the cinnamon fern, but the latter grow in crowns, with a single frond in the center, while the fronds of the chain fern rise singly from the creeping rootstock, which sends them up at intervals all summer. The sori are borne on the backs of fertile fronds.

There are usually more sterile than fertile blades, especially in dense shade. We have waded repeatedly through a miry swamp in Melrose, Ma.s.s., where the wild calla flourishes along with the blueberry and other swamp bushes, and have found the chain fern in several shaded spots, but every frond was sterile. It is said that when exposed to the sun it always faces the south. Swamps, Maine to Florida, especially along the Atlantic Coast, and often in company with the narrow-leaved species.

[Ill.u.s.tration: Net-Veined Chain Fern. _Woodwardia areolata_ (Stratford, Conn.)]

(2) NET-VEINED CHAIN FERN

NARROW-LEAVED CHAIN FERN

_Woodwardia areolata. W. angustiflia_

Root stocks creeping and chaffy. Sterile and fertile fronds unlike; sterile ones nine to twelve inches tall, deltoid-ovate. Broadest at the base, with lanceolate, serrulate divisions united by a broad wing. Veins areolate; fertile fronds taller, twelve to twenty inches high with narrowly linear divisions, the areoles and fruit-dots in a single row each side of the secondary midrib, the latter sunk in the tissues.

This species is less common than the Virginia fern, but they often grow near each other. We have collected both in the Blue Hill reservation near Boston, and both have been found in Hingham, Medford, and Reading, and doubtless in other towns along the coast. Mrs. Parsons speaks of finding them in the flat, sandy country near Buzzard's Bay. The net-veined species has some resemblance to the sensitive fern, but in the latter the spore cases are shut up in small pods formed by the contracting and rolling up of the lobes, whereas the chain fern bears its sori on the under side of long, narrow pinnae. Besides, the sterile fronds of the latter have serrulate segments. As in the sensitive fern there are many curious gradations between the fertile and sterile fronds, both in shape and fruitfulness.

Waters calls them the "_obtusilobata_ form."

[Ill.u.s.tration: The Spleenworts 1. Narrow-leaved 2. Ebony 3. Rue 4. Scott's 5. Maidenhair 6. Green 7. Mountain]

THE SPLEENWORTS

A. THE ROCK SPLEENWORTS. _Asplenium_

Small, evergreen ferns. Fruit-dots oblong or linear, oblique, separate when young. Indusium straight or rarely curved, fixed lengthwise on the upper side of a fertile veinlet, opening toward the midrib. Veins free. Scales of rhizome and stipes narrow, of firm texture and with thick-walled cells.

(1) PINNaTIFID SPLEENWORT. _Asplenium pinnatifidum_

Fronds four to six inches long, lanceolate, pinnatifid or pinnate near the base, tapering above into a slender prolongation. Lobes roundish-ovate, or the lower pair ac.u.minate. Fruit-dots irregular, numerous. Stipes tufted, two to four inches long, brownish beneath, green above.

Although this fern, like all the small spleenworts, is heavily fruited, it is extremely rare. It is found as far north as Sharon, Conn., thence southward to Georgia, to Arkansas and Missouri. On cliffs and rocks.

Resembles the walking fern, and its tip sometimes takes root.

(2) SCOTT'S SPLEENWORT. _Asplenium ebenides_

Fronds four to ten inches long, broadly lanceolate, pinnatifid or pinnate below, tapering to a prolonged and slender apex. Divisions lanceolate from a broad base. Fruit-dots straight or slightly curved. Stipe and rachis brown.

[Ill.u.s.tration: Pinnatifid Spleenwort. _Asplenium pinnatifidum_ a, Small Plants from Harper's Ferry; b, Sori on Young Fronds (From Waters's "Ferns,"

Henry Holt & Co.)]

[Ill.u.s.tration: Scott's Spleenwort. _Asplenium ebenoides_ a, from Virginia; b, from Alabama; c, from Maryland (From Waters's "Ferns," Henry Holt & Co.)]

Resembles the last, and like that has been known to root at the tip. It is a hybrid between the walking fern and the ebony spleenwort, as proved by Miss Margaret Slosson, and may be looked for in the immediate vicinity of its parents. It was discovered by R.R. Scott, in 1862, at Manayunk, Pa., a suburb of Philadelphia, and described by him in the Gardener's Monthly of September, 1865. Vermont to Alabama, Missouri, and southward. Rare, but said to be plentiful in a deep ravine near Havana, Ala.

[Ill.u.s.tration: Green Spleenwort. _Asplenium viride_]

(3) GREEN SPLEENWORT. _Asplenium viride_

Fronds two to ten inches long, linear, pinnate, pale green. Pinnae roundish-ovate, crenate, with indistinct and forking midveins. Stalks tufted, short, brownish below, green above. Rachis green.

Discovered at Smuggler's Notch, Mt. Mansfield, Vt., by C.G. Pringle in 1876. Found sparingly at Willoughby Lake, high on the cliffs of Mt. Horr.

This rare and delicate little plant bears a rather close resemblance to the maidenhair spleenwort, which, however, has dark stipes instead of green.

Northern New England, west and northwest on shaded limestone rocks.

[Ill.u.s.tration: Maidenhair Spleenwort. _Asplenium Trichomanes_]

(4) MAIDENHAIR SPLEENWORT. _Asplenium Trichomanes_

Stipes densely tufted, purple-brown, shining. Fronds three to eight inches long, linear, dark green, rather rigid. Pinnae roundish-oblong or oval, entire or finely crenate, attached at the base by a narrow point. Midveins forking and evanescent.

Not very common, but distributed almost throughout North America. May be looked for wherever there are ledges, as it does not require limestone.

July.

[Ill.u.s.tration: Maidenhair Spleenwort. _Asplenium Trichomanes_ (From Woolson's "Ferns," Doubleday, Page & Co.)]

(5) SMALL SPLEENWORT

_Asplenium parvulum. A. resiliens_

Fronds four to ten inches tall, narrowly linear, rather firm, erect. Pinnae opposite, oblong, entire or finely crenate, and auricled at the base.

Stipes and rachis black and shining. Midveins continuous.

This small fern is a southern species half way between the maidenhair and ebony spleenworts, but rather more like the latter from which it differs in being smaller and thicker, and in having the fertile and sterile fronds of the same size. Mountains of Virginia to Kansas and southward.

(6) EBONY SPLEENWORT

_Asplenium platyneuron. A. ebeneum_